Lomita City Council
October 7, 2025

January 2020

EXHIBIT A
Tuesday, October 07, 2025 Reg CC MTG, Page *237

Local Assistance Procedures Manual Exhibit 16-T2
Materials Requiring a Certificate of Compliance per the Greenbook 20 Structural Steel Products 207-12.2.1 General (Materials) Specific language/info required on the COC. 21 Structural Aluminum Products 207-14.2.1 General (Materials) Specific language/info required on the COC. 22 PVC Pipe 207-17.4.1 General (Test Requirements)
23 PolyPropylene Pipe 207-25.6.1 General (Man. Facility Testing) 24 Materials used in Sewers 211-2 Chemical Resistance (Pickle Jar) Test Specific language/info required on the COC. 25 Viscometer Calibration 211-4.2 Calibration
26 Engineering Geosynthetics 213-1 General (Engineering Geosynthetics) Specific language/info required on the COC. 27 Traffic Paint, Thermo and Markers 214-2 Test Reports And Cert. of Compliance Specific language/info required on certified test reports OR COC
28 Precast Reinforced Concrete Box 216-8 Basis of Acceptance 29 Fiberglass Standards 700-3.3.4 Fiberglass Standards Specific language/info required on the COC and test reports. 30 Conductors for Series Circuits, 5000V 700-4.2.2 Conductors for Series Circuits 31 Conductors and Cable 700-5.3.1 General (Conductors and Cable) 32 Lamp Receptable Conductors 700-5.5.7 Electrical Components COC Required if required information is not marked on the insulation.
33 LED Signal Modules 700-5.5.11.8 Certificate of Compliance 34 LED Pedestrian Signal Module 700-5.6.6.7 Certificate of Compliance

January 2020

EXHIBIT A
Tuesday, October 07, 2025 Reg CC MTG, Page *238
Division of Local Assistance, Office of Procedures Development and Training Quality Assurance Program (QAP) Manual for Use by Local Agencies ATTACHMENT – 4

MATERIALS CERTIFICATE

EXHIBIT A
Tuesday, October 07, 2025 Reg CC MTG, Page *239

Local Assistance Procedures Manual Exhibit 17-G
Materials Certificate
Exhibit 17-G: Materials Certificate

MATERIALS CERTIFICATE

CITY/COUNTY LETTERHEAD
(Sample)
Date:

Federal-Aid Project Number:

Caltrans File Category 61:

Job Stamp:

Subject: Materials Certification
This is to certify that:

The results of the tests on acceptance samples indicate that the materials incorporated in the construction work and the construction operations controlled by sampling and testing were in conformity with the approved plans and specifications.

Exceptions to the plans and specifications are explained on the back of this memorandum (or on attached sheet).

No exceptions to the plans and specifications were found.

Signature of local agency engineer in responsible charge of project and title Distribution: (For all projects) 1) Local agency Project Files (original) 2) DLAE (1 copy in Report of Expenditures)
(For projects on the NHS) 3) FHWA (1 copy)

January 2022

EXHIBIT A
N/A - Caltrans Use N/A - Caltrans Use
Tuesday, October 07, 2025 Reg CC MTG, Page *240
Division of Local Assistance, Office of Procedures Development and Training Quality Assurance Program (QAP) Manual for Use by Local Agencies ATTACHMENT - 5
Example of a Log Summary Sheet
Subgrade Materials
Date CT Station Elevation Test
Results
Minimum
Spec.

Passed
or Failed
Action
Taken
5/15/07 231 1+ 00 (30’ L) 99.00 93 90 or greater Passed N/A 5/16/07 231 1+ 50 (20’ R) 100.50 94 90 or greater Passed N/A 5/17/07 231 2+ 25 (25’ R) 101.00 96 90 or greater Passed N/A 5/18/07 231 1+ 50 (30’ L) 101.50 95 95 or greater Passed N/A 5/19/07 231 2+ 50 (20’ L) 102.00 92 * 95 or greater Failed See Note 1 5/19/07 231 2+ 50 (20’ L) 102.00 95 95 or greater Passed N/A CT 231 = Compaction (Nuclear Gage)
* Note 1: The Contractor used a water tank to dampen the soil surface at the failed subgrade location. Using a sheep’s foot compactor, he reworked the subgrade (making at least 10 passes) from Station 2+ 00 to Station 3+ 00. After approximately 30 minutes, another compaction test was taken. This time the relative compaction was 95.

Aggregates and Base Materials
Date CT Station Elevation Test ResultsMinimum
Spec.

Passed
or Failed
Action
Taken
6/20/07 202 1+ 00 (10’ R) 102.50 See data
sheet
See data sheet Passed N/A
6/20/07 202 2+ 00 (20’ L) 102.50 See data
sheet
See data sheet Passed N/A
6/22/07 217 1+ 00 (10’ R) 102.50 75 25 or greater Passed N/A 6/22/07 217 2+ 00 (20’ L) 102.50 83 25 or greater Passed N/A 6/20/07 227 1+ 00 (20’ R) 102.50 86 71 or greater Passed N/A 6/20/07 227 1+ 50 (20’ L) 102.50 85 71 or greater Passed N/A 6/24/07 231 2+ 00 (20’ R) 102.50 98 95 or greater Passed N/A 6/24/07 231 2+ 50 (20’ L) 102.50 97 95 or greater Passed N/A CT 202 = Sieve Analysis, CT 217 = Sand Equivalent, CT 227 = Cleanness Value, CT 231 = Compaction (Nuclear Gage)

EXHIBIT A
Tuesday, October 07, 2025 Reg CC MTG, Page *241
Division of Local Assistance, Office of Procedures Development and Training Quality Assurance Program (QAP) Manual for Use by Local Agencies ATTACHMENT - 5
(continued)
Hot Mix Asphalt
Date CT Station Elevation Test
Results
Minimum
Spec.

Passed or
Failed
Action
Taken
7/10/07 339 1+ 00
(10’ R)
103.00 0.08 gal/
sq yd

0.05 -0.10
gal/sq yd
Passed N/A
7/10/07 366 2+ 00
(20’ L)
103.00 32 >23 Passed N/A
7/10/07 366 1+ 00
(10’ R)
103.00 41 >23 Passed N/A
7/10/07 375 2+ 00
(20’ L)
103.00 94 RC = 93 to
97 Passed N/A
7/15/07 375 1+ 00
(20’ R)
103.00 96 RC = 93 to
97 Passed N/A
7/15/07 375 1+ 50
(20’ L)
103.00 95 RC = 93 to
97 Passed N/A
CT 339 = Distributor Spread Rate, CT 366 =
Stabilometer Value CT 375 = In-Place Density & Relative Compaction
Portland Cement Concrete
Date CT Station Elevation Test
Results
Minimum
Spec.

Passed or
Failed
Action
Taken
9/25/07 504 10 + 50
(50’ R)
102.50 6.5% >6.0% Passed N/A
9/25/07 533 12 + 50
(50’ R)
102.50 1.5” <2” Passed N/A
9/25/07 518 11 + 50
(50’ R)
102.50 151 lb/cu ft > 145 lb/cu
ft
Passed N/A
9/25/07 521 10 + 50
(50’ R)
102.50 28 day =
4200 psi
>3800 psi Passed N/A
9/28/07 521 11 + 50
(50’ R)
102.50 28 day =
4290 psi
>3800 psi Passed N/A
9/30/07 521 12 + 50
(50’ R)
102.50 28 day =
4160 psi
>3800 psi Passed N/A
CT 504 = Air Content, CT 518 = Unit Weight, CT 521 = Compressive Strength, CT 533 = Ball Penetration

EXHIBIT A
Tuesday, October 07, 2025 Reg CC MTG, Page *242
Division of Local Assistance, Office of Procedures Development and Training Quality Assurance Program (QAP) Manual for Use by Local Agencies ATTACHMENT - 6
(Exhibit 16-Z2)

EXHIBIT A
Tuesday, October 07, 2025 Reg CC MTG, Page *243

APPENDIX VI

CERTIFICATION REGARDING LOBBYING

EXHIBIT A
Tuesday, October 07, 2025 Reg CC MTG, Page *244
OMB Control No. 200-0020
Approval expires 04/0/2021
The public reporting and recordkeeping burden for this collection of information is estimated to average 15 minutes per response.

Send comments on the Agency's need for this information, the accuracy of the provided burden estimates, and any suggested methods for minimizing respondent burden, including through the use of automated collection techniques to the Director, Collection Strategies Division, U.S. Environmental Protection Agency (2822T), 1200 Pennsylvania Ave., NW, Washington, D.C. 20460. Include the OMB control number in any correspondence. Do not send the completed form to this address.

United States

ENVIRONMENTAL PROTECTION AGENCY
Washington, DC 20460
EPA Form 6600-06 (Rev. 06/2014) Previous editions are obsolete. ________________________________________________________________________________________________ _________________________________
EPA Project Control Number

CERTIFICATION REGARDING LOBBYING

CERTIFICATION FOR CONTRACTS, GRANTS,

LOANS AND COOPERATIVE AGREEMENTS
The undersigned certifies, to the best of his or her knowledge and belief, that:
(1) No Federal appropriated funds have been paid or will be paid, by or on behalf of the undersigned, to any person for influencing or attempting to influence an officer or employee of any agency, a Member of Congress, an officer or employee of Congress, or an employee of a Member of Congress in connection with the awarding of any Federal contract, the making of any Federal grant, the making of any Federal loan, the entering into of any cooperative agreement, and the extension, continuation, renewal, amendment, or modification of any Federal contract, grant, loan, or cooperative agreement.
(2) If any funds other than Federal appropriated funds have been paid or will be paid to any person for influencing or attempting to influence an officer or employee of any agency, a Member of Congress in connection with this Federal contract, grant, loan, or cooperative agreement, the undersigned shall complete and submit Standard Form-LLL, “Disclosure Form to Report Lobbying,” in accordance with its instructions. (3) The undersigned shall require that the language of this certification be included in the award documents for all sub-awards at all tiers (including sub-contracts, sub-grants, and contracts under grants, loans, and cooperative agreements) and that all sub-recipients shall certify and disclose accordingly.

This certification is a material representation of fact upon which reliance was placed when this transaction was made or entered into. Submission of this certification is a prerequisite for making or entering into this transaction imposed by section 1352, title 31 U.S. Code. Any person who fails to file the required certification shall be subject to a civil penalty of not less than $10,000 and not more than $100,000 for each such failure.
______________________________________________
Typed Name & Title of Authorized Representative
______________________________________________
Signature and Date of Authorized Representative

EXHIBIT A
Tuesday, October 07, 2025 Reg CC MTG, Page *245

APPENDIX VII

CALTRANS CONSTRUCTION SITE BMP

FIELD MANUAL

EXHIBIT A
Tuesday, October 07, 2025 Reg CC MTG, Page *246
State of California
Department of Transportation
Construction Site
Best Management Practice
(BMP)
Field Manual
and
Troubleshooting Guide
CTSW-RT-02-007
January 2003

EXHIBIT A
Tuesday, October 07, 2025 Reg CC MTG, Page *247
Construction Site BMP Field Manual and Troubleshooting Guide

TABLE OF CONTENTS
PART I: INTRODUCTION ......................................................................................................1 Principles of Erosion and Sediment Control ........................................................................................... ......................................................................................... 1 Common Pollutants on the Construction Site 2
Monitoring and Inspection Program .......................................................................................................3 PART II: PROJECT OPERATIONS AND BMPS ..................................................................7 PART III: BMP IMPLEMENTATION AND TROUBLESHOOTING ................................11 TEMPORARY SOIL STABILIZATION ...........................................................................................11 SS-2 Preservation of Existing Vegetation .....................................................................................11 SS-3 Hydraulic Mulch ...................................................................................................................13 SS-4 Hydroseeding ........................................................................................................................15 SS-5 Soil Binders ..........................................................................................................................17 SS-6 Straw Mulch .........................................................................................................................19 SS-7 Geotextiles, Plastic Covers, Erosion Control Blankets & Mats ...........................................21 SS-8 Wood Mulching ....................................................................................................................24 SS-9 Earth Dikes, Drainage Swales & Ditches .............................................................................26 SS-10 Outlet Protection/Velocity Dissipation Devices ...................................................................28 SS-11 Slope Drains .........................................................................................................................30 TEMPORARY SEDIMENT CONTROL ...........................................................................................32 SC-1 Silt Fence ..............................................................................................................................32 SC-2 Desilting Basin .....................................................................................................................35 SC-3 Sediment Trap ......................................................................................................................37 SC-4 Check Dam ...........................................................................................................................39 SC-5 Fiber Rolls ............................................................................................................................41 SC-6 Gravel Bag Berm ..................................................................................................................43 SC-7 Street Sweeping and Vacuuming ..........................................................................................45 SC-8 Sandbag Barrier ....................................................................................................................47 SC-9 Straw Bale Barrier ................................................................................................................49 SC-10 Storm Drain Inlet Protection .................................................................................................51 WIND EROSION CONTROL .............................................................................................................53 WE-1 Wind Erosion Control...........................................................................................................53 TRACKING CONTROL ......................................................................................................................54 TC-1 Stabilized Construction Entrance/Exit ..................................................................................54 TC-2 Stabilized Construction Roadway.........................................................................................56 NON-STORM WATER MANAGEMENT .........................................................................................57 NS-1 Water Conservation ..............................................................................................................57 NS-2 Dewatering Operations .........................................................................................................59 NS-3 Paving and Grinding Operations ..........................................................................................61 NS-4 Temporary Stream Crossing .................................................................................................63 NS-5 Clear Water Diversion ..........................................................................................................65 NS-7 Potable Water/Irrigation .......................................................................................................67 NS-8 Vehicle and Equipment Cleaning .........................................................................................68 NS-9 Vehicle and Equipment Fueling ...........................................................................................70 NS-10 Vehicle and Equipment Maintenance ...................................................................................72 NS-11 Pile Driving Operations........................................................................................................74 NS-12 Concrete Curing ....................................................................................................................76 NS-13 Material and Equipment Use on Water ................................................................................77 i

EXHIBIT A
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Construction Site BMP Field Manual and Troubleshooting Guide NS-14 Concrete Finishing ................................................................................................................79 NS-15 Structure Demolition/removal Over or Adjacent to Water ...................................................81 NS-16 Temporary Batch Plants .......................................................................................................83 NS-17 Streambank Stabilization ......................................................................................................84 WASTE MANAGEMENT AND MATERIALS POLLUTION CONTROL ...................................85 WM-1 Material Delivery and Storage ..............................................................................................85 WM-2 Material Use .........................................................................................................................87 WM-3 Stockpile Management .........................................................................................................88 WM-4 Spill Prevention and Control ................................................................................................90 WM-5 Solid Waste Management .....................................................................................................92 WM-6 Hazardous Waste Management ............................................................................................94 WM-7 Contaminated Soil Management ..........................................................................................96 WM-8 Concrete Waste Management ...............................................................................................98 WM-9 Sanitary/Septic Waste Management ...................................................................................101 WM-10 Liquid Waste Management .................................................................................................103 PART IV: NOTES .....................................................................................................................104 District Construction Storm Water Coordinators................................................................................104 Caltrans Headquarters Environmental Website ..................................................................................104 Comments And Questions ..................................................................................................................104

LIST OF TABLES
Table 1 Storm Water BMPs for Construction Operations......................................................................7 ii

EXHIBIT A
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Introduction
PART I: INTRODUCTION
This document provides a toolbox for Caltrans field pe rsonnel to aid in proper implementation of water pollution control Best Management Practices (BMPs) on the construction site. The document is organized into the following parts:
• Part I: Introduction briefly presents (1) the principles of erosion and sediment control, (2) common storm water pollutants on the construction site , and (3) guidelines for implementing a proper monitoring and inspection program for the construc tion site, including the use of the Storm Water Pollution Prevention Plan (SWPPP) or Water Pollu tion Control Program (WPCP) to ensure an effective water pollution control program.
• Part II: Project Operations and BMPs identifies typical water pollution control challenges for specific construction operations and the BMPs th at are available to meet those challenges. • Part III: BMP Implementation and Troubleshooting provides guidance for installing, maintaining and troubleshooting selected BMPs from the Caltrans Storm Water Quality Handbooks, Construction S

PRINCIPLES OF EROSION AND SEDIMENT CONTROL
ite BMPs Manual.

The greatest water pollution threat from soil-disturbi ng activities is the introduction of sediment from the construction site into storm drain systems or natu ral receiving waters. Soil-disturbing activities such as clearing, grubbing, and earthwork increase the exposure of soils to wind, rain, and concentrated flows that cause erosion. A three-pronged approach is n ecessary to combat this storm water threat:
• Temporary soil stabilization practices reduce erosion associated with disturbed soil areas (DSAs). • Temporary run-on control practices prevent storm water flows (sheet and concentrated) from contacting DSAs.
• Temporary sediment control practices reduce sedimen t caused by erosion from entering a storm drain system or receiving water.

Soil stabilization BMPs reduce the erosive impact of rain on exposed soil. Run-on control practices reduce the erosive impacts by preventing storm water flows from contacting DSAs. Sediment control BMPs remove sediment from storm water by ponding a nd settling, and/or filtering prior to discharge offsite. It is imperative that soil stabilization and sediment control BMPs are implemented together to reduce the discharge of sediment from the construction site.

The following conditions on construction sites contri bute to erosion caused by storm water flows:
• Larger areas of impermeable structures and surfaces reduce natural infiltration resulting in increased storm water flow volume and velocity.
• Changes to surface flow patterns cause storm water flows to be more erosive. • Concentration of flows to areas that are not naturally subjected to such runoff volume increases erosion.
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Introduction
Proper management of a construction project minimizes or prevents soil erosion and sediment discharges.

Good construction management for soil conservation requires an understanding of the following basic principles:

Soil Erosion Control – The First Line of Defense
Soil stabilization is a key component in the control of erosion. By stabilizing DSAs with covers or binders, the exposed soils are less likely to erode from the effects of wind or rain.

Prevent Storm Water Flows from Contacting DSAs – The Second Line of Defense Another key component in the control of erosion is the diversion of storm water flows around DSAs or the conveyance of flows through DSAs in a non-erosive manner.

Sediment Control – The Last Line of Defense
Storm water runoff may originate from active or inac tive DSAs whether or not proper erosion and/or run-on controls have been implemented. Impl ementing proper sediment control BMPs can reduce sediment amounts in storm water discharges.

Combine Soil Erosion and Sediment Control – Effective Protection An effective combination of soil erosion and sediment controls should be implemented to prevent sediment from leaving the site and/or entering a storm water drainage system or receiving water.

Soil stabilization and other erosion control BMPs ar e not 100 percent effective at preventing erosion.

Soil erosion control BMPs must be supported by sediment control BMPs to capture sediment on the construction site.

Sediment control BMPs alone are not 100 percent e ffective primarily due to their capacity limits. To be effective for storm water protection, the amount of sediment must be reduced at the source using soil erosion control BMPs, and then sediment contro l BMPs are used to further reduce the sediment that leaves the site or enters the storm drain system.

Inspection and Maintenance – Ensure Protect ion for the Duration of the Project Inspection and maintenance are required for all BMPs (soil stabilization, run-on control, and sediment control) to maintain effectiveness for reducing or eliminating the amount of sediment that leaves a site.

COMMON POLLUTANTS ON THE CONSTRUCTION SITE
There are a number of potential storm water pollutant s that are common to Caltrans construction sites.

The soil-disturbing nature of construction activities and the use of a wide range of construction materials and equipment are the sources of contaminants with the potential to pollute storm water discharges.

Common construction activities that increase the pot ential for polluting storm water with sediment include:
• Clearing and grubbing operations
• Demolition of existing structures
• Grading operations
• Soil importing and stockpiling operations
• Clear water diversions
• Landscaping operations
• Excavation operations
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Introduction
Common construction materials with the potential to c ontribute pollutants, other than sediment, to storm water include the following:
• Vehicle fluids, including oil, grease, petroleum, and coolants • Asphalt concrete (AC) and Portland cemen t concrete (PCC) materials and wastes • Joint seal materials and concrete curing compounds
• Paints, solvents, and thinners
• Wood products
• Metals and plated products
• Fertilizers, herbicides, and pesticides
Construction-related waste must also be managed to prevent its introduction into storm water. Typical waste on construction sites includes:
• Used vehicle fluids and batteries
• Wastewater from vehicle cleaning operations
• Green waste from vegetation removal
• Non-storm water from dewatering operations
• Trash from materials packaging, employee lunch/meal breaks, etc. • Contaminated soils
• Slurries from sawing and grinding operations
• Wastewater/waste from concrete washout operations
• Hazardous materials waste
• Sanitary waste

MONITORING AND INSPECTION PROGRAM
The Resident Engineer is responsible for ensuring th at Caltrans personnel monitor the contractor’s water pollution control practices and maintain complian ce with the approved project SWPPP/WPCP. This includes reviewing the contractor’s SWPPP/WPCP, reviewing written inspection reports, and conducting field inspections. Caltrans Structures personnel should also be aware of the water pollution control requirements and participate in the monitoring program.

Step 1: Do Your Homework
a. Review the Storm Water Quality Handbooks: Construction Site BMPs Manual.

Caltrans personnel with storm water responsib ilities should familiarize themselves with BMP requirements. In particular, become familiar with (1) the rainy season dates for your geographical area, (2) the definitions of DSA, active DSA, and non-active DSA, and (3) the requirements for soil stabilization and sediment control BMPs for the season and specific Rainfall Area. b. Review the Project Plans.

Review the Project Plans in the context of stor m water pollution control. Visualize storm water run-on and runoff flow patterns when reviewing the plans. Review the general layout and existing drainage courses. Identify potential problem areas where storm water may run onto the site or discharge off site.
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Introduction
Identify the locations where structures are being constructed or modified. Be familiar with the right-of-way and easement limits. Determine the limits of clearing and grubbing activities.

Identify the project phase or stage. Try to de termine DSAs and Environmentally Sensitive Areas (ESAs). Is the next phase going to include soil-disturbing activities and is it scheduled within the rainy season? Do the DSAs have provisions in the plans for permanent erosion control? Determine if permanent erosion control can be placed when activity in the DSA is complete. c. Review the Special Provisions
Review the Special Provisions for site-specifi c water pollution control requirements such as:
(1) permits for the construction project, (2) limits on active DSAs, (3) rainy season dates and requirements, (4) minimum BMP requirements, (5) BMP maintenance and inspection requirements, and (6) final erosion control requirements. Final erosion control requirements include (1) required products, (2) application process, (3) application rate, (4) seeding window, and (5) planting requirements.

The Special Provisions also include a section on water pollution control permits or requirements imposed on the project by other agencies. Typical agencies include the California Department of Fish and Game, Army Corps of Engineers, local flood control agencies, and others. There may be special requirements for water bodies or ESAs that need special water pollution control consideration.

Review the Special Provisions bid items related to water pollution control. There may be lump sums or unit prices for water pollution control items including SWPPP/WPCP preparation, permanent erosion control, and temporary erosion and sediment controls.

Review the Special Requirements section of the Sp ecial Provisions for site-specific activities such as: (1) dewatering, (2) sampling and analysis, (3) BMP maintenance cost allocation between Caltrans and the contractor, and (4) sanctions against the contractor in the event of noncompliance with the water pollution control requirements. d. Review the SWPPP/WPCP.

The SWPPP or WPCP for the project is the cont ractor’s plan to ensure conformance with Caltrans’ water pollution control requirement s on the construction site. The SWPPP/WPCP contains details about the BMPs to be used on the site, their locations, implementation timeframes, and inspection and maintenance sche dules. The contractor must comply with the approved SWPPP/WPCP. If conditions change on the construction site that impact storm water pollution controls, the contractor must amend the SWPPP/WPCP.

In the SWPPP, Section 200 contains the approval signature and lists any amendments. Section 300 describes unique features of the construction site and contains the construction and water pollution control schedules. Section 500 identifi es the BMPs selected for soil stabilization, sediment control, non-storm water controls, waste management, and materials disposal controls and references locations on the vicinity map and water pollution control drawings.

In a WPCP, Section 10 contains the approval signatures. Section 20 describes the unique features of the site and contains the schedule. Section 30 identifies the selected BMPs, the vicinity map and water pollution control drawings. Section 40 contains any WPCP amendments. e. Review the Contractor’s Schedule .

The accepted Baseline schedule as well as the m onthly updates and three-week “look-ahead” schedules are important references to better an ticipate which BMPs will be implemented or 4 EXHIBIT A
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Introduction
needed. A project schedule is required in both SWPPPs and WPCPs and must show how the rainy season relates to soil-disturbing and re-stabilization activities and must also show major activities sequenced with implementation of BMPs.

Step 2: Establish an Inspection Schedule
a. Prior to the rainy season, inspect the site to en sure that the contractor has the necessary materials to stabilize required DSAs and to implement the necessary sediment controls. b. Year round, inspect the construction site prior to a forecast storm, after a rain event that causes runoff from the construction site, and at 24-hour intervals during an extended rain event. c. Conduct inspections at other frequenci es as required by the Special Provisions. d. Work with the Project Storm Water Coordi nator, the District Construction Storm Water Coordinator, and SWTF Inspectors during site inspections and to receive assistance when necessary.

Step 3: Conduct the Inspection
a. Use the most recent Storm Water Quality Construction Site Inspection Checklist to document the inspection. The checklist is provided in Attachment H of the Caltrans Storm Water Quality Handbooks, SWPPP and WPCP Preparation Manual. This is the same checklist used by the contractor for conducting inspections. Instructions for using the checklist are also provided in Attachment H.
b. Encourage the contractor to participate in the inspection. This provides the opportunity for verbal feedback and discussion.
c. If the project involves significant structures work, encourage the Structures representative or inspector to participate in the inspection. Take a copy of the most current and approved site plan(s) and SWPPP on the inspection for identification of site features and for taking notes at specific areas.
d. Fill out the Inspection Checklist and add findings in writing. Use clear and concise language and give specific locations where problems were observed.
e. Take photographs during the inspection to document the existing conditions. This is especially important if the contractor does not attend the inspection. When photos of problem areas are taken, try to follow up with photos showing corrections. f. Inspect the entire site, including the perimeter, especially where there is potential for run-on or discharge from the site. Look for areas of potentia l concentrated flows and for adjacent water bodies or drainage facilities that may be affected by discharges from the site. Start the inspection at the lowest point, or the area with the high est potential for discharge. Inspect all potential discharge points. The SWPPP/WPCP should identify discharge points, however, there may be areas with discharge potential that were not identified in the SWPPP/WPCP. g. Inspect the contractor’s yard(s), where required.
h. Look for changes in construction or site conditions that may require an amendment to the SWPPP/WPCP.
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Introduction
i. Inspect for proper implementation of non-storm water management BMPs and waste management and materials pollution control BMPs.
j. For inspections during the rainy season, evaluate active and non-active DSAs. (The Resident Engineer should periodically evaluate the classification of construction areas as active DSAs or non-active DSAs.) Determine the total area of DS A and compare it to the limit for DSAs in the Special Provisions. If the existing DSA exceeds the limit, identify areas that can be stabilized to reduce the amount. Active DSAs require protection pr ior to the onset of rain. Evaluate erosion and sediment control BMPs based on the requirements related to Rainfall Area, season and active/non-active status as defined in the SWPPP/WP CP and BMP Manual. Be sure to inspect the entire site during a rain event, especially when run-off from the site occurs. Confer with the District Construction Storm Water Coordinator as to the district’s definition of a rain event and maintain weather reports in the SWPPP file.
k. During the non-rainy season, identify the active and non-active DSAs. Depending on the Rainfall Area, DSAs may continue to require erosion and sediment control BMPs during the nonrainy season. l. For individual BMPs, note if the BMP is properly installed. Also note if the BMP is in need of repair or maintenance.

Step 4: Report Inspection Results
a. If the Resident Engineer did not attend the in spection, communicate the results to the Resident Engineer.
b. Ideally, observations should be discussed with the contractor during the inspection. c. Missing BMPs and non-compliance issues must be communicated to the contractor. Refer to the contractor’s SWPPP/WPCP for required BMPs.

Step 5: Follow-up with Corrective Measures
The contractor must install missing BMPs and correct improperly installed or damaged BMPs immediately or by a date and time as approved in writing by the Resident Engineer. In any event, corrections must be made prior to the next rain event.
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Project Operations and BMPs
PART II: PROJECT OPERATIONS AND BMPS
Table 1 identifies individual BMPs that are appli cable to specific construction operations. The BMPs listed in the table are for general consideration dur ing each phase of operations. The indicated BMPs may not be applicable to every construction operation, nor is every possible BMP listed for each construction operation. The Resident Engineer should determin e the appropriateness of an individual BMP to a construction site.

Table 1 Storm Water BMPs for Construction Operations
Construction Operation BMPs
(See Part III for Details)
Mobilization
SC-7 Street Sweeping and Vacuuming
TC-1 Stabilized Construction Entrance/Exit
TC-2 Stabilized Construction Roadway
TC-3 Entrance/Outlet Tire Wash
NS-6 Illicit Connection/ Illegal Discharge Detection and Reporting WM-1 Material Delivery and Storage
WM-2 Material Use
WM-4 Spill Prevention and Control
WM-5 Solid Waste Management
WM-6 Hazardous Waste Management
WM-9 Sanitary/Septic Waste Management
Clearing/Grubbing
SS-1 Scheduling
SS-2 Preservation of Existing Vegetation
SS-3 Hydraulic Mulch
SS-4 Hydroseeding
SS-5 Soil Binders
SS-6 Straw Mulch
SS-7 Geotextiles, Plastic Covers & Erosion Control Blankets/Mats SS-8 Wood Mulching
SS-9 Earth Dikes/Drainage Swales & Lined Ditches
SS-10 Outlet Protection/Velocity Dissipation Devices
SS-11 Slope Drains
SC-1 Silt Fence
SC-2 Desilting Basin
SC-3 Sediment Trap
SC-4 Check Dam
SC-5 Fiber Rolls
SC-6 Gravel Bag Berm
SC-7 Street Sweeping and Vacuuming
SC-8 Sandbag Barrier
SC-9 Straw Bale Barrier
SC-10 Storm Drain Inlet Protection
WE-1 Wind Erosion Control
NS-1 Water Conservation Practices
NS-8 Vehicle and Equipment Cleaning
NS-9 Vehicle and Equipment Fueling
NS-10 Vehicle and Equipment Maintenance
WM-3 Stockpile Management
WM-5 Solid Waste Management
WM-7 Contaminated Soil Management
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Project Operations and BMPs
Construction Operation BMPs
(See Part III for Details)
Earthwork
SS-1 Scheduling
SS-2 Preservation of Existing Vegetation
SS-3 Hydraulic Mulch
SS-4 Hydroseeding
SS-5 Soil Binders
SS-6 Straw Mulch
SS-7 Geotextiles, Plastic Covers & Erosion Control Blankets/Mats SS-8 Wood Mulching
SS-9 Earth Dikes/Drainage Swales & Lined Ditches
SS-10 Outlet Protection/Velocity Dissipation Devices
SS-11 Slope Drains
SC-1 Silt Fence
SC-2 Desilting Basin
SC-3 Sediment Trap
SC-4 Check Dam
SC-5 Fiber Rolls
SC-6 Gravel Bag Berm
SC-7 Street Sweeping and Vacuuming
SC-8 Sandbag Barrier
SC-9 Straw Bale Barrier
SC-10 Storm Drain Inlet Protection
TC-1 Stabilized Construction Entrance/Exit
WE-1 Wind Erosion Control
NS-4 Temporary Stream Crossing
NS-8 Vehicle and Equipment Cleaning
NS-9 Vehicle and Equipment Fueling
NS-10 Vehicle and Equipment Maintenance
WM-7 Contaminated Soil Management
PCC and
AC Operations
SC-7 Street Sweeping and Vacuuming
TC-1 Stabilized Construction Entrance/Exit
NS-3 Paving and Grinding Operations
WM-1 Material Delivery and Storage
WM-2 Material Use
WM-3 Stockpile Management
WM-5 Solid Waste Management
WM-8 Concrete Waste Management
Drainage Work
SC-2 Desilting Basin
SC-3 Sediment Trap
SC-4 Check Dam
SC-10 Storm Drain Inlet Protection
SS-9 Earth Dikes/Drainage Swales & Lined Ditches
SS-10 Outlet Protection/Velocity Dissipation Devices
Dewatering Operations NS-2 Dewatering Operations
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Project Operations and BMPs
Construction Operation BMPs
(See Part III for Details)
Bridge Construction
NS-1 Water Conservation Practices
NS-3 Paving and Grinding Operations
NS-4 Temporary Stream Crossing
NS-5 Clear Water Diversion
NS-8 Vehicle and Equipment Cleaning
NS-9 Vehicle and Equipment Fueling
NS-10 Vehicle and Equipment Maintenance
WM-1 Material Delivery and Storage
WM-2 Material Use
WM-3 Stockpile Management
WM-4 Spill Prevention and Control
WM-5 Solid Waste Management
WM-6 Hazardous Waste Management
WM-8 Concrete Waste Management
WM-10 Liquid Waste Management
NS-3 Paving and Grinding Operations
NS-4 Temporary Stream Crossing
NS-5 Clear Water Diversion
Roadway Construction
WM-1 Material Delivery and Storage
WM-2 Material Use
WM-3 Stockpile Management
WM-5 Solid Waste Management
WM-6 Hazardous Waste Management
WM-8 Concrete Waste Management
WM-10 Liquid Waste Management
Mobile Operations
SC-7 Street Sweeping and Vacuuming
SC-10 Storm Drain Inlet Protection
TC-1 Stabilized Construction Entrance/Exit
NS-8 Vehicle and Equipment Cleaning
NS-9 Vehicle and Equipment Fueling
NS-10 Vehicle and Equipment Maintenance
WM-1 Material Delivery and Storage
WM-2 Material Use
WM-3 Stockpile Management
WM-5 Solid Waste Management
WM-6 Hazardous Waste Management
WM-8 Concrete Waste Management
Trenching Operations
SC-7 Street Sweeping and Vacuuming
SC-10 Storm Drain Inlet Protection
WM-3 Stockpile Management
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Project Operations and BMPs
Construction Operation BMPs
(See Part III for Details)
Erosion Control,
Highway Planting and
Landscaping
SS-1 Scheduling
SS-2 Preservation of Existing Vegetation
SS-3 Hydraulic Mulch
SS-4 Hydroseeding
SS-5 Soil Binders
SS-6 Straw Mulch
SS-7 Geotextiles, Plastic Covers & Erosion Control Blankets/Mats SS-8 Wood Mulching
SS-9 Earth Dikes/Drainage Swales & Lined Ditches
SS-10 Outlet Protection/Velocity Dissipation Devices
SC-1 Silt Fence
SC-7 Street Sweeping and Vacuuming
SC-8 Sandbag Barrier
SC-9 Straw Bale Barrier
SC-10 Storm Drain Inlet Protection
WE-1 Wind Erosion Control
NS-7 Potable Water/Irrigation
NS-8 Vehicle and Equipment Cleaning
WM-1 Material Delivery and Storage
WM-2 Material Use
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Preservation of Existing Vegetation SS-2
11 PART III: BMP IMPLEMENTATION AND TROUBLESHOOTING

TEMPORARY SOIL STABILIZATION
SS-2 PRESERVATION OF EXISTING VEGETATION
Preservation of existing vegetation involves the identification and protection of desired vegetation.

Applications
Delineate Environmentally Sensitive Areas (ESAs)
Delineate areas where no construction activities are planned Delineate areas where construction activities will occur at a later date Delineate areas outside the project right-of-way or boundary Key Points
Key Point # 1 – Timing
Areas to be protected should be delineated prior to clearing and grubbing operations or other soildisturbing activities. It is also appropriate for areas where no construction activity is planned or where activity is planned for a later date (Photo 1).

Key Point # 2 – Layout
Areas of existing vegetation that are scheduled for preservation should be clearly marked with a temporary fence (Photo 2). Minimize disturbance by locating temporary roadways, storage facilities, and parking areas away from preserved vegetation.

Photo 1 Photo 2
Key Point # 3 – Training
Instruct employees, workers, surveyors, and subcontractors to honor protective devices. Maintain any existing irrigation systems and vegetation.

Key Point # 4 –Tree Preservation
Keep equipment away from trees to prevent root a nd trunk damage. Trenching should be as far away from tree trunks as possible, typically outside the drip lin e. Trenches should be filled in as soon as possible to avoid root drying. Fill trenches carefully and tamp the soil to fill in air pockets. Never expose roots to the air.

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Preservation of Existing Vegetation SS-2
Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Vehicles and equipment run into or over
vegetation that is to be preserved.

Clearly mark areas of preservation, and instruct workers to honor those areas.

Existing vegetation dies from lack of watering. Maintain existing irrigation systems and ensure that they function properly.

Preserved trees are damaged.

Keep equipment and vehicles away from trees to prevent
trunk and root damage. Severely damaged trees should be attended to by an arborist.

ESAs or areas where construction is not to occur
or can occur at a later date are not delineated for
protection.

Verify vegetation that requires preservation. Stop work if necessary. Delineate area as needed.
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13 Hydraulic Mulch SS-3
SS-3 HYDRAULIC MULCH
Hydraulic mulch is a mixture of shredded wood fiber or hydraulic matrix, water, and a stabilizing emulsion or tackifier. Applied hydraulic mulch will he lp protect bare soil from water and wind erosion.

Bonded Fiber Matrix (BFM) is another soil stabilizer alternative to hydraulic mulch.

Applications
Temporary protection for DSAs until permanent vegetation is established Temporary protection for DSAs that will be re-disturbed following an extended period (1 to 3 months) of inactivity
Key Points
Key Point #1 – Application
Wood fiber mulches are mixed in a hydroseeder and applied as liquid slurry. Material is applied from a spray gun on a tower (Photo 1) or from a hose (Photo 2).

Photo 1 Photo 2
Key Point #2 – Hydraulic Matrix Vs. Hydraulic Mulch
A hydraulic matrix, as opposed to a basic wood fiber hy draulic mulch, consists of a wood fiber base layer and a paper fiber top layer mixed with a binding agent and applied as a liquid slurry. Paper based hydraulic mulches alone shall not be used for temporary soil stabilization applications.

Key Point #3 – Bonded Fiber Matrix
A bonded fiber matrix (BFM) consists of a continuous layer of elongated wood fiber strands mixed with a bonding agent. Again, the material is applied as a liquid slurry. Once dried, a high strength, porous, and erosion resistant mat is created (Photo 3).

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Hydraulic Mulch SS-3
Photo 3
Key Point #4 – Avoid Over Spraying
Do not over spray onto the traveled way, sidewalks, lined channels, etc. (Photo 4).

Key Point #5 – After Application
In addition, ensure that areas to be sprayed will rema in inactive or undisturbed. This slope was disturbed after bonded fiber matrix was applied (Photo 5).

Photo 4 Photo 5
Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Slope was improperly dressed before application. Roughen embankment and fill areas first by rolling with crimping or punching type roller or by track walking.

Coverage is inadequate.

Follow recommended application rates. Count the number
of bags of the product to ensure the correct amount of
material is used.

Allowed inadequate drying time.

Allow at least 24 hours for the material to dry before a rain event. Follow manufacturer’s recommendations. Reapply
where necessary.

Portions of the mulch have been disturbed. Keep workers and equipment off the mulched areas and repair areas that have been damaged.

Excess water flows across stabilized surface.

Use other BMPs to limit flow onto stabilized area. Use
other BMPs to reduce slope lengths. Do not use to stabilize areas with swift moving concentrated flows.
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Hydroseeding SS-4
15 SS-4 HYDROSEEDING
Hydroseeding typically consists of applying a mixtur e of fiber, seed, fertilizer, and stabilizing emulsion with hydro-mulch equipment to temporarily protect exposed soils from erosion by water and wind.

Applications
Temporary protection for DSAs until permanent vegetation is established Temporary protection for DSAs that will be re-distu rbed following an extended period (6 to 12 months) of inactivity
Key Points
Key Point #1 – Hydroseeding Mixture Selection
Select a hydroseeding mixture by evaluating site conditions with respect to:
• Soil conditions and soil type.
• Site topography - steep slopes are difficult to protect with temporary seeding. • Season and climate - seeding during summer or in arid areas may limit germination and plant establishment.
• Water availability - temporary or permanent irri gation may be needed for germination and plant establishment.
• Sensitive adjacent areas - seeding should be compatib le with adjacent ESAs. If incompatible seeding is to be used, ensure that seeds are not sprayed or blown onto the sensitive area. • The Landscape Architect or the Construction Stor m Water Coordinator shall approve hydroseeding mixtures.

Key Point #2 – Temporary Measure
If permanent vegetation is to be applied in th e seeded area, the temporary vegetation from the hydroseeding may need to be removed. For exampl e, grasses that inhibit compaction of soil to the required density must be removed before permanent vegetation is applied.

Key Point #3 – Preparation and Application
Roughen areas to be hydroseeded by plowing or disk ing with furrows trending along the contours. Avoid over spraying onto sidewalks, lined drainage channels, roadways, or existing vegetation (Photo 1).

Key Point #4 – Inspection and Maintenance
All seeded areas should be inspected for failures. Rea pply seed, fertilizer, mulch, and water as needed to maintain coverage and encourage plant establishment. After grasses are established, mowing may be required to reduce fire hazard (Photo 2).

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Hydroseeding SS-4
Photo 1 Photo 2
Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Slope was improperly dressed before application. Roughen slopes. Furrow along the contour of areas to be seeded.

Coverage is inadequate.

Follow recommended application rates. Count the number
of seed bags of the product to ensure the correct amount of material is being applied. Reapply to thin areas.

Seeds fails to germinate.

Apply straw mulch to keep seeds in place and to moderate soil moisture and temperature. In arid areas, temporary irrigation may be necessary.

Seeded slope fails. Fill in rills and re-seed; fertilize and mulch slopes.

Seeding is washed off slope.

Allow at least 24 hours for the materials to dry before a rain event. Follow manufacturer’s recommendations. Reapply
where necessary.

Excessive water flows across stabilized surface.

Use other BMPs to limit flow on stabilized area. Use other BMPs to reduce slope lengths. Do not use to stabilize areas with swift moving concentrated flows.
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Soil Binders SS-5
17 SS-5 SOIL BINDERS
Soil binders are materials applied to the soil surface to temporarily reduce erosion of exposed soils on construction sites. Soil binders consist of applying and maintaining polymeric or lignin sulfonate soil stabilizers or emulsions.

Applications
Temporary protection for DSAs that will be re-disturbed following a period of inactivity Depending on the type of soil binder, the period of effectiveness is three months to two years Key Points
Key Point #1 – Product Selection
Select soil binders by evaluating the site with respect to:
• Soil types and surface materials
• Suitability to the situation
• Performance and longevity requirements
Key Point #2 – Preparation
Prepare soil before applying the binder so that the binder adheres to and penetrates the soil surface. The untreated surface must be roughened (Photo 1) and must contain sufficient moisture (Photo 2) for the binder to achieve uniform penetration.

Photo 1 Photo 2
Key Point #3 – Curing
Soil binders require a minimum curing time before beco ming fully effective, therefore binders should not be applied during or immediately before rainfall.

Key Point #4 – Product Constituents
When selecting a product, consider the chemical com ponents and review the Material Safety Data Sheet (MSDS). If the product has a potential for becoming a pollutant, consider using a different product.

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Soil Binders SS-5
Key Point #5 – Inspection and Maintenance
Inspect the areas of application after rainfall for signs of erosion (Photo 3).

Inspect high traffic areas daily and low traffic areas on a weekly basis. High traffic areas are those exposed to daily use (vehicle or foot traffic) by c ontractor, subcontractor, or other personnel. Low traffic areas are those available for use but not in a daily manner.

Reapply soil binder as necessary (Photo 4).

Photo 3 Photo 4
Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Slope was improperly dressed before application.

Roughen embankment and fill areas by rolling with a
crimping or punching type roller or track walking where rolling is impractical. Pre-wet the areas of application.

Coverage is inadequate.

Follow recommended application rates. Count the number
of bags of the product to ensure the correct amount of
material is implemented. Reapply to the areas.

Sprayed areas degrade or become ineffective. Follow recommended application rates. Consider other or additional BMPs. Reapply binder as necessary.

Sprayed slope has spot failures. Repair slopes and re-spray damaged areas.

Portions of the sprayed area have been disturbed. Keep workers and equipment off sprayed areas. Repair and re-spray areas that have been damaged.

Binder fails to penetrate soil. Roughen soil and pre-wet to manufacturer’s recommendations. Reapply to areas where necessary.

Soil binder is washed off slope.

Allow at least 24 hours for the materials to dry before a rain event. Follow manufacturer’s recommendations. Reapply as necessary.

Excessive water flows across stabilized surface.

Use other BMPs to limit flow onto stabilized area. Use
other BMPs to reduce slope lengths. Do not use to stabilize areas with swift moving concentrated flows.
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Straw Mulch SS-6
19 SS-6 STRAW MULCH
Straw mulch consists of placing a uniform layer of st raw and incorporating it into the soil with a studded roller or anchoring it with a tackifier. Straw mu lch is used as a temporary surface cover for soil stabilization on DSAs until soils can be prepared for re-v egetation. It is also used in combination with temporary and/or permanent seeding strategies to enhance plant establishment.

Applications
Temporary protection for DSAs (6 to 12 months)
Used in combination with temporary and/or permanent seeding to enhance plant establishment Key Points
Key Point #1 – Application Rate
Straw mulch must be evenly distributed on the soil surface (Photo 1). Proper application rates should be followed so that mulch covers the soil in a uniform layer without any visible bare spots.

Key Point #2 – Application Methods
Straw mulch can be applied mechanically or by ha nd (Photo 2). Mechanical application involves a straw blower (Photo 3) and may require an access road or driving surface capable of supporting the equipment.

When using a straw blower, schedule the appli cation to avoid excessive windblown straw. Manual application is time and labor inte nsive and should be used only on small areas or where equipment access is not feasible.

Photo 1 Photo 2
Key Point #3 – Anchoring
The preferred method for anchoring straw mulch in place is to use a tackifier. Other methods for anchoring the mulch include crimping (Photo 4), punching, or track walking. Crimping and punching are mechanical methods of anchoring the mulch to the soil. Track walking should be used only where rolling is impractical.

Key Point #4 – Inspection and Maintenance
Inspect straw mulches prior to and after rainstor ms. Repair any damaged ground cover and re-mulch exposed areas of bare soil.

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Straw Mulch SS-6
Photo 3 Photo 4
Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Mulch blows away. Anchor straw mulch in place by applying a tackifier, crimping, punching, or track walking. May need to use a different BMP.

Coverage is inadequate. Follow recommended application rates. Count the number of bales per acre to ensure the correct amount of material is implemented. Reapply as necessary.

Excessive water flows
across stabilized surface.

Use other BMPs to limit flow onto stabilized area and/or to reduce slope lengths. Do not use to stabilize areas with swift moving concentrated flows. 20 EXHIBIT A
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Geotextiles, Plastic Covers, Erosion Control Blankets & Mats SS-7 21 SS-7 GEOTEXTILES, PLASTIC COVERS, EROSION CONTROL BLANKETS & MATS This BMP involves the placement of geotextiles, plastic covers, and erosion control blankets and mats to stabilize DSAs and protect soil from erosion by wind or water. Typically these measures are used on slopes near ESAs, as a quick stopgap measure, and when DSAs are particularly difficult to stabilize.

Applications
Steep slopes that are generally steeper than 1:3 (V:H)
Slopes where the erosion potential is high
Disturbed areas where plants are slow to develop
Stockpiles
Slopes adjacent to water bodies in or near ESAs
Key Points
Key Point #1 – Product Selection
There are many types of erosion control blankets and mats available (Photo 1). Select a product appropriate for the application a nd site conditions. Selection criteria include: (1) effectiveness for reducing erosion, flow velocity, and runoff; (2) acceptability for environmental compatibility, institutional / regulatory requirements, and visual impact; (3) co mpatibility with native plants, moisture retention, temperature modification, and open space coverage; (4) durability, longevity, ease of installation; and (5) maintenance frequency.

Key Point #2 – Site Preparation
Site preparation is essential to ensure that blankets and mats perform as intended. Remove all rocks, clods, vegetation or other obstructions and re-grade to allow the blanket or mat to come into complete contact with the soil. Improper slope preparation prev ents the blanket from fully contacting the soil, and allows water to flow under the blanket (Photo 2).

Photo 1 Photo 2
Key Point #3 – Slope Installation
Install the product starting from the top of the slope (Photo 3), anchored in a 150 mm by 150 mm (6 in by 6 in) trench that is backfilled and tamped firmly. Unroll the blankets down the slope, laying them loosely and stapling every 1 m (3 ft). Do not stretch blankets. Ensure that the blanket maintains direct contact with the soil. Overlap the edges of adjacent pa rallel rolls by 50 mm to 75 mm (2 in to 3 in).

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Geotextiles, Plastic Covers, Erosion Control Blankets & Mats SS-7 Photo 3
Key Point #4 – Inspection and Maintenance
Inspect blanket and mat installations periodically and after significant rainstorms for signs of erosion or undermining. Repair or replace any failures immediately. If washout or breakage of material occurs, reinstall material after repairing damage to slope or channel. Maintain areas treated with temporary soil stabilization to provide adequate erosion control. Reapply or replace temporary erosion controls on exposed soils when visibly eroded or when there is a 10 percent or greater exposure of the previously treated area.

Preventive Measures and Troubleshooting Guide
Field Condition (Geotextiles): Common solutions are:

Undercutting occurs along the top of the slope.

Dig a 150 mm by 150 mm (6 in by 6 in) trench along the
top of the slope and anchor blanket into trench by back filling and tamping the soil.

Blankets separate along the seams. Overlap adjacent blanket 50 mm to 75 mm (2 in to 3 in) and staple every 1 m (3 ft).

Blankets separate where the rolls are attached end
to end.

Shingle the blanket so the top blanket covers the bottom blanket by 150 mm (6 in) and staple through the overlapped areas every 300 mm (12 in)
Blanket does not make complete contact with the
soil surface.

Prepare the soil surface by removing, rocks, clods , sticks and vegetation, fill in rill and uneven areas
Excessive water flows across stabilized surface.

Use other BMPs to limit flow on stabilized area. Use other BMPs to reduce slope lengths. Do not use to stabilize areas with swift moving concentrated flows.
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Geotextiles, Plastic Covers, Erosion Control Blankets & Mats SS-7 Field Condition (Plastics): Common solutions are:

Undercutting occurs along the top of the slope. Dig a trench along the top of the slope and anchor blanket into trench by back filling and tamping the soil.

Plastic sheeting separates along the seams. Overlap edges of plastic sheeting by 300 mm to 600 mm (12 in to 24 in) and tape the entire length or weight down.

Plastic sheeting tears and separates.

Overlap plastic sheets by 300 mm to 600 mm (12 in to 24 in), tape edges together or weigh down. Maintain
installation by replacing torn areas.

Plastic sheet is blown or displaced by winds. Weigh down sheet to protect from wind. Maintain installation by replacing sheets in position.

Field Condition (Blankets and Mats): Common solutions are:

Improper anchoring. Dig trench along the top and bury the blankets. Use staples to anchor according to manufacturer’s recommendations.

Undercutting due to inadequate preparation.

Prepare the soil surface. Remove rocks, clods and other obstructions. Fill in rills in uneven areas to promote good contact between mat and soil.

Excessive water flow across stabilized surface.

Use other BMPs to limit flow onto stabilized area. Use
other BMPs to reduce slope lengths. Do not use to stabilize areas with swift moving concentrated flows.
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Wood Mulching SS-8
24 SS-8 WOOD MULCHING
This BMP consists of applying a mixture of shredded wood mulch, bark, or compost to bare soil to reduce runoff, increase infiltration, and reduce erosion due to rainfall impact. Wood mulch provides temporary or short-term soil stabilization primarily for landscaping projects.

Applications
Temporary protection of DSAs pending estab lishment of permanent vegetative cover As a permanent non-vegetative ground cover on slopes
Key Points
Key Point #1 – Product Selection
Select wood mulch products appropria te for the application and site conditions. Prior to placement, consult with the District Landscape Ar chitect to ensure that the mulch is compatible with planned future projects.

Key Point #2 – Preparation
After existing vegetation has been removed, roughe n embankment and fill areas by rolling with a punch type roller or track walking (Photo 1) before applying the wood mulch.

Photo 1
Key Point #3 – Mulch Depth
Mulch depth depends on the product selected such as green material or shredded wood (Photo 2).

Distribute shredded wood mulch evenly (Photo 3) across the soil to a depth of 50 mm (2 in) to 75 mm (3 in). Mulch composed of recycled green waste should be applied to a maximum depth of 50 mm (2 in).

Key Point #4 – Inspection and Maintenance
Inspect and maintain mulch to ensure that it last s long enough to achieve the erosion control objectives.

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Wood Mulching SS-8
Photo 2 Photo 3
Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Area was improperly dressed before application.

Remove existing vegetation and roughen embankment and
fill areas by rolling with a punch type roller or by track walking.

Coverage is inadequate. Follow recommended application rates. Inspect the areas to ensure that the mulch is applied to the correct depth.

Mulch is washed away. Do not place mulch in concentr ated flow areas. Reapply as necessary or use another BMP.

Excessive water flows across stabilized surface.

Use other BMPs to limit flow onto stabilized area. Use
other BMPs to reduce slope lengths. Do not use to stabilize areas with swift moving concentrated flows.
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Earth Dikes, Drainage Swales & Ditches SS-9
26 SS-9 EARTH DIKES, DRAINAGE SWALES & DITCHES
Earth dikes, drainage swales, and lined ditches are structures that intercept, divert, and convey surface runoff around or through the project site in a non-erosive manner.

Applications
To convey surface runoff down sloping land
Along paved surfaces to intercept runoff
Along the top of slopes to divert surface flow from slopes To divert and direct runoff towards stabilized drainage systems Below steep grades where runoff begins to concentrate
Key Points
Key Point #1 – Sediment Control
It may be necessary to use other water pollution contro l practices such as check dams, plastic sheeting, or blankets to prevent scour and erosion in the swales, dikes, and ditches.

Key Point #2 – Flow Velocity
Select flow velocity for ditches, swales, and dik es based on careful evaluation of potential risk due to erosion, over topping, flow backup, washout, and dr ainage flow patterns for each project. In some cases the drainage swale may need to be constructed with asphalt concrete (Photo 1).

Photo 1
Key Point #3 – Location Selection
Care must be applied to correctly size and locate earth dikes, drainage swales, and lined ditches.

Excessively steep, unlined dikes and swales may be subj ect to erosion and gully formation. Earth dikes, drainage swales and ditches are not suitable as sediment trapping devices.

Key Point #4 – Inspection and Maintenance
Inspect temporary measures prior to the rainy season, after rainfall events and regularly (approximately once every two weeks) during the rainy season. Insp ect channels, embankments, and ditch beds for erosion, washout, and accumulation of sediment and debris. Repair or replace lost riprap, linings, or soil stabilization as needed.

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Earth Dikes, Drainage Swales & Ditches SS-9
Preventive Measures and Troubleshooting Guide
Field Condition (Earth Dikes): Common solutions are:

Dikes wash out. Compact the soil used to build the earthen dikes.

Area behind dikes erode. Stabilize the area. Use other BMPs to stabilize the uphill side of the dike, such as SS-7.

Concentrated flow causes erosion. Stabilize conveyances and/or use check dams, plastic, or blankets to control erosion.

Outlet erodes. Stabilize outlets, replace lost riprap
Field Condition (Drainage Swales and Ditches): Common solutions are:

Ditches and swales erode due to high velocity
flows.

Line channels with permanent stabilization. Place riprap or line channel with blankets or plastics. Add velocityreducing BMPs upstream, e.g. check dams.

Swales and ditches fill up with sediment. Remove accumulated sediment from ditches and swales.

Stabilize upstream contributing ar eas with a soil stabilizer.

Ditches and swales are overtaken by flows. Determine the upstream contributing areas and size ditches and swales to handle anticipated flow velocities.

Conveyances erode. Place check dams as necessary to reduce flow velocities.

Stabilize conveyances with plastic and/or blankets.
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Outlet Protection/Velocity Dissipation Devices SS-10
28 SS-10 OUTLET PROTECTION/VELOCITY DISSIPATION DEVICES This BMP requires the placement of rock, riprap, or othe r material at pipe outlets to reduce flow velocity of exiting storm water and thus prevent scouring.

Applications
Outlets of pipes, drains, culverts, slope drains, diversion ditches, swales, conduits, or channels Outlets located at the bottom of mild to steep slopes
Outlets subject to intense water flows
Outlets that carry continuous flows of water
Points where lined conveyances discharge to unlined conveyances Key Points
Key Point #1 – Riprap Selection
The minimum riprap diameter is determined by the outlet diameter, discharge volume, and apron length.

Outlets with slopes greater than 10% need additional protection. Flow rate and local climate may dictate whether loose rock (Photo 1) or grouted riprap is appropriate. High flows may wash loose rock away.

Grouted riprap may break up in areas of freeze and thaw.

Key Point #2 – Unprotected Outlets
Flows from unprotected pipe outlets can result in severe erosion (Photo 2). Use a flared end section or riprap at the outlet to reduce flow velocity and erosive potential of concentrated flows.

Photo 1 Photo 2
Key Point #3 – Installation
Carefully place riprap to prevent damage to underlyi ng filter fabric. Where large riprap is used, the underlying filter fabric may need to be protected with a rock blanket.

Key Point #4 – Inspection and Maintenance
Inspect temporary velocity dissipation devices prior to the rainy season, after rainfall events and regularly (approximately once every two weeks) during the rainy season. Inspect aprons for riprap displacement or damage to underlying fabric. Inspect for scour ben eath the riprap and around the outlets, and repair as needed.

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Outlet Protection/Velocity Dissipation Devices SS-10
Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Riprap washes away. Replace riprap with a larger diameter based on the pipe diameter and discharge velocity.

Apron is displaced.

Align apron with receiving water and keep it straight
throughout its length. Repair fabric and replace riprap that has washed away.

Scour occurs around apron or riprap. Repair damage to slopes or underlying filter fabric.

Outlet erodes. Stabilize outlets; replace lost riprap; grout riprap. 29 EXHIBIT A
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Slope Drains SS-11
30 SS-11 SLOPE DRAINS
A slope drain conveys water down a slope into a stab ilized receiving water, trapping device, or stabilized area. Slope drains are used with lined ditches to convey surface flow away from slope areas to protect cut or fill slopes.

Applications
Where concentrated flows are directed over a slope
Key Points
Key Point #1 – Limitations
Severe erosion may result if a slope drain fa ils due to over topping or pipe separation.

Key Point #2 – Drainage Constraints
Limit the area draining to a slope drain to 4 ha (10 ac) per pipe. Large areas may require the use of a rocklined channel or a series of pipes. The maximum slope gradient is generally limited to 1:2 (V:H), as the ability to dissipate water velocity from steeper slopes is difficult.

Key Point #3 – Installation
Install slope drains perpendicular to the slope contour (Photo 1). Compact the soil around and under the slope drain inlet, outlet, and along the length of the pipe . Protect the pipe inlet with filter fabric or flared end sections for pipes that are greater than 300 mm (12 in) in diameter. Ensure that pipe connections are watertight. Securely anchor and stabilize th e pipe and appurtenances into the soil.

Photo 1
Key Point #4 – Velocity Dissipation
Protect outlet with riprap or velocity dissipation de vices. For high-velocity discharges, reinforce riprap with concrete or reinforced concrete devices. It may be necessary to capture discharge and allow sediment to settle out.

Key Point #5 – Inspection and Maintenance
Inspect before and after each rain event and twice monthly until the tributary drainage area has been stabilized. Inspect outlets for erosion and downstream scour. In the event of scour, reduce the flows going into the channel unless other preven tive measures can be implemented.

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Slope Drains SS-11
Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Pipe separates. Reconnect pipe sections. Securely anchor and stabilize pipe into soil. Ensure that pipe connections are watertight.

Pipe outlet erodes.

Repair damage and stabilize outlet with a flared end
section, riprap, or velocity dissipation device. If necessary, reduce flows being discharged.

Pipe becomes clogged. Flush out pipe. Place a screen or grate at inlet to capture large particles.

Erosion occurs around inlet. Stabilize area around inlet with filter fabric or flared end section. Re-grade around inlet to reduce the gradient angle.

Excessive sediment accumulates around
inlet/outlet. Remove accumulated sediment and stabilize upstream area.

Slope drain overtops.

Limit drainage area and flow velocity. Check pipe diameter to ensure that it is sized properly to accept flow. Add additional pipes to carry flows as necessary.
31 EXHIBIT A
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Silt Fence SC-1
32 TEMPORARY SEDIMENT CONTROL
SC-1 SILT FENCE
Silt fence is a temporary linear barrier that captures sediment by ponding and filtering storm water runoff to allow sediment to settle out of the runoff water.

Application
Below the toe of slopes as required
Down slope of exposed soil areas
Around temporary stockpiles as required
Key Points
Key Point #1 – Installation
Install on a relatively level contour. This means the barrier should be installed as close as possible to a level horizontal plane near the toe of the slope (Phot o 1). Turn the end of the barrier up the slope to prevent ponded water from escaping around the end (Photo 2).

Photo 1 Photo 2
Key Point #2 – Setback
A silt fence should be placed with a setback of at l east 1 m (3 ft). Where a 1 m (3 ft) setback is not practicable due to site conditions, the fence may be c onstructed at the toe of slope but should be placed as far from the toe as practicable to increase the ponding area and allow sediment to settle out.

Key Point #3 – Key In
The bottom of the silt fence must be keyed in or wa ter may flow underneath (Photo 3). A trench should be excavated along the proposed layout line of the fence. Af ter the silt fence stakes have been driven into the trench, backfill over the fence fabric and compact (Photo 4).

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Silt Fence SC-1
Photo 3 Photo 4
Key Point #4 – Cross Barriers
For silt fence installed on a level contour with long reaches, install cross barriers at a minimum of 150 m (500 ft) intervals. For silt fence not installed on a le vel contour, install cross barriers, at a minimum, where the change in elevation equals 1/3 the height of the silt fence.

Key Point #5 – Limitations
Do not install silt fence across intermittent or pe rmanent streams, channels, or any location where concentrated flow is anticipated (Photos 5 and 6).

Photo 5 Photo 6
Key Point #6 – Inspection and Maintenance
Perform inspection before and after rain events, ev ery 24 hours during extended rain events, and weekly throughout the rainy season. Should silt fence fabric tear (Photo 7) or decompose, replace immediately.

Remove sediment deposits (Photo 8) when the sediment accumulation reaches 1/3 of the barrier height. 33 EXHIBIT A
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Silt Fence SC-1
Photo 7 Photo 8
Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

There is excessive sediment accumulation.

Remove sediment. Apply Hydraulic Mulch (SS-3) or Straw
Mulch (SS-6) or other BMP upstream to reduce sediment in runoff.

Bottom of fence is not properly keyed in. Trench, place fabric, and backfill.

Length of slope draining to silt fence is too long. Shorten slope length using Fiber Rolls (SC-5) or equivalent.

Slope shall be 61 m (200 ft) or less.

Storage capacity is inadequate due to sediment
buildup.

Remove accumulated sediment when it reaches 1/3 the
height of the barrier.

There is a lack of sufficient ponding area. Fence should be installed with at least a 1m setback from the toe of slope where possible. Divert flow at top of slope.

Erosion occurs around barrier ends. Turn ends of barriers into the up-slope area.

Silt fence is not installed along level enough
contour.

Reinstall silt fence so that change in elevation does not exceed 1/3 the height of the linear barrier along the reach.

Install cross barriers.

Slope draining to fence is too steep. Slope shall be
less than 1:1 (V:H).

Shorten slope length using Fiber Rolls (SC-5) or equivalent.

Increase setback of silt fence from the toe of slope.

Fence is installed in concentrated flow area. Replace fence with proper BMP such as Check Dams (SC-4), if appropriate.

Cross barriers not installed or installed incorrectly.

Place cross barriers on the receiving side of the barrier at a maximum separation of 150 m. Cross barrier should be a
minimum of 1/3 and a maximum of ½ the height of the
linear barrier.

Stakes are too far apart. Add stakes a maximum of 2.5 m apart.

Concentrated flows cause erosion to occur behind
silt fence. Place cross barrier check dams behind the barrier. 34 EXHIBIT A
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Desilting Basin SC-2
35 SC-2 DESILTING BASIN
A desilting basin is a temporary basin formed by ex cavation and/or construction of an embankment so that storm water runoff is temporarily detained, a llowing sediment to settle out before the water is discharged.

Applications
Where storm water can enter a drainage system or receiving water from a construction area At outlets of DSAs between 2 and 4 ha (5 and 10 ac) in size Key Points
Key Point #1 – Capacity
Desilting basins shall be designed to have a capacity of 100 m3 of storage for every 1 ha (55 yd3 per acre) of contributory area. Basin storage capacity is measured from the top of the basin to the principal outlet.

Basins must be designed to drain within 72 hours follo wing storm events. Basins with levees greater than

1.5 m (5 ft) in height or with an impounding capacity of 1000 m3 (1300 yd3) or greater shall be designed
by a professional Civil Engineer registered with the state of California.

Key Point #2 – Configuration
The basin inlet shall be located to maximize travel di stance to the basin outlet. The outlet structure should be placed as far away from the inlet structure as possi ble to maximize travel distance and allow suspended sediment to settle out.

Key Point #3 – Basin Dimensions
The length of the basin shall be more than twice the wi dth of the basin. Basin depth must not be less than one 1 m (3 ft) or greater than 1.5 m (5 ft). Check the approved SWPPP for actual dimensions.

Key Point #4 –- Limitations
Basins generally require excavation of large surface areas so that sediment will settle out efficiently. The availability of right-of-way may limit basin size or de ployment on construction sites. Basins may not be located in live streams. Basins may requi re protective fencing to ensure safety.

Key Point #5 – Inspection and Maintenance
Inspect basins before and after rainfall events, w eekly during the rainy season, and at 24 hours intervals during extended storm events. Check inlet and outle t structures and spillways for signs of erosion, damage, or obstructions. Examine basin banks for seepage and structural soundness. Remove accumulated sediment when the basi n storage capacity is 1/3 full.

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Desilting Basin SC-2
Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Outlet pipe is clogged with debris.

Clean outlet pipe. Wrap outlet pipe with filter fabric or install fencing or trash rack around pipe to hold back larger debris particles.

Spillway erodes due to high velocity flows. Stabilize outlet with riprap or line spillway with plastic sheeting or geotextile blankets.

Slope sides erode. Stabilize slopes with rock, vegetation, or equivalent method.

There is excessive accumulated sediment buildup. Remove sediment to retain holding capacity.

The upstream drainage area is too large.

Ensure that the basin is designed to accommodate the
inflow for the designed storm. Limit contributing drainage area or expand basin. Ensure drainage area does not exceed 4 ha (10 ac). If the drainage area does exceed this limit, use other or additional BMPs.
36 EXHIBIT A
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Sediment Trap SC-3
37 SC-3 SEDIMENT TRAP
A sediment trap is a temporary basin formed by excavation or by construction of an earthen embankment across a waterway or low drainage area and has a controlled release structure.

Applications
Permissible where contributing area is less than 2 ha (5 ac) Sites where storm water can enter a storm drain or receiving water from a construction area As a supplemental control for reducing sediment before it enters a drainage system or receiving water Key Points
Key Point #1 – Location
Traps should be excavated in a suitable area or by constructing a low embankment across a swale where failure would not pose a risk to life or property. Traps should provide access for maintenance, including sediment removal.

Key Point #2 – Configuration
The trap inlet shall be located as far away from th e trap outlet to maximize travel distance and allow suspended sediment to settle out (Photo 1).

Key Point #3 – Dimensions
The length of the trap shall be more than three times the width (Photo 2). Traps with levees greater than

1.5 m (5 ft) in height or with a storage capacity greater than 1000 m 3 (1300 yd3) shall be designed by a
professional Civil Engineer registered with the stat e of California. Check the approved SWPPP for actual dimensions.

Photo 1 Photo 2
Key Point #4 – Limitations
Traps generally require excavation of large surface areas to permit settling of sediment. The availability of right-of-way may limit their size or deployment on construction sites. Sediment traps should be limited to drainage areas of 2 ha (5 ac) or less. Traps ma y not be located in live streams. Traps may require protective fencing to ensure safety.

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Sediment Trap SC-3
Key Point #5 – Inspection and Maintenance
Traps should be inspected before and after rainfall events, weekly during the rainy season, and at 24-hour intervals during extended storm events. Check inle t and outlet structures and spillways for signs of erosion, damage, or obstructions. Examine trap banks for seepage and structural soundness. Remove accumulated sediment when the trap storage capacity is 1/3 full.

Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Outlet pipe is clogged with debris.

Clean out pipe. Wrap outlet pipe with filter fabric or install fencing or trash rack around pipe to hold back larger debris particles.

Spillway erodes due to high velocity flows. Stabilize outlet with riprap or line spillway with plastic sheeting or geotextile blankets.

Slope sides erode. Stabilize slopes with rock, vegetation or equivalent method.

Accumulated sediment has built up. Remove sediment to recover holding capacity.

Drainage area is too large.

Ensure that the trap is designed to accommodate the inflow for the designed storm. Limit drainage contributing area.

Consider other or additional BMPs.
38 EXHIBIT A
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Check Dam SC-4
39 SC-4 CHECK DAM
A check dam is a small structure constructed of rock or gravel bags placed across a natural or man-made channel or drainage ditch. Check dams reduce scour and channel erosion by reducing flow velocity and encouraging sediment to settle out.

Applications
In small open channels that drain 4 ha (10 ac) or less
In steep channels where storm water r unoff velocities exceed 1.5 m/s (5 ft/s) In drainage ditches or channels in which grass linings are being established In temporary ditches where a short-term service do es not warrant establishment of erosion resistant linings
In combination with other BMPs such as sediment basins and traps Key Points
Key Point #1 – Installation
Install check dams 5 m (16 ft) from the outfall device and at regular intervals along the channel based on the erosion characteristics and slope degree of the drainage swale (Photo 1). Swales that are very steep or have a high potential of eroding require check dams placed closer together.

Key Point #2 – Dimensions
Check dams should be placed at a height and distance as to allow small pools to form behind them but allow high velocity flows (typically a 2-year storm or larger) to safely flow over them without an increase in upstream flooding or damage to the check dam. Check dams should be constructed to pond runoff flows so that the backwater from the downstream ch eck dam reaches the toe of the upstream dam (Photo 2).

Photo 1 Photo 2
Key Point #3 – Limitations
Check dams should not be placed in live streams or in channels that are already grass-lined unless erosion is expected, as existing vegetation may be damaged. Check dams are not appropriate in channels that drain areas greater than 4 ha (10 ac).

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Check Dam SC-4
Key Point #4 – Inspection and Maintenance
Check dams require extensive maintenance after storm events or high velocity flows to repair damage (Photo 3). Remove sediment when it reaches 1/3 the check dam height.

Photo 3
Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Too much sediment has accumulated. Remove accumulated sediment to recover holding capacity.

There is insufficient ponding area. Space check dams farther apart. Increase height of dam.

The check dam is higher than the drainage
channel.

Lower check dam so that it is 150 mm (6 in) lower than the channel side.

Check dams wash away.

Ensure that the drainage area is 4 ha (10 ac) or less.

Replace check dams. Consider adding more dams
upstream.

Wrong type of materials is used to construct
barrier .

Use heavier materials such as larger rocks. Do not use
straw bales or silt fence.
40 EXHIBIT A
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Fiber Rolls SC-5

SC-5 FIBER ROLLS
A fiber roll consists of straw, flax, or similar materi al that is rolled and bound into a tight tubular cylinder and placed at regular intervals on a slope face. Fiber rolls intercept runoff, reduce runoff flow velocity, and release the runoff as sheet flow. Fiber rolls are also used as a filter to remove sediment from runoff.

Applications
Along the top, face, and at grade breaks of exposed and erodible slopes Key Points
Key Point #1 – Installation
Proper fiber roll installation is crucial to ensure effectiveness and performance. Fiber rolls should be placed on a level contour in a shallow trench with a maximum depth of 50 mm to 100 mm (2 in to 4 in).

The fiber roll should be staked at each end and at regular intervals along its length with a maximum distance of 1.2 m (4 ft) between stakes. If more than one fiber roll is placed in a row, the ends of the adjoining rolls should be tightly abutte d together and not overlapped (Photo 1).

Key Point #2 – Vertical Spacing
When used to create storm water benches on a slope, the vertical spacing of the fiber rolls rows is determined by the inclination and length of the slope (Photo 2). For slopes 1:2 (V:H) and steeper and 15 m (50 ft) and greater, fiber rolls shall be placed at intervals no greater than 7.5 m (25 ft). For slopes between 1:20 (V:H) and 1:2 (V:H) and 30 m (100 ft) and greater, fiber rolls shall be placed at intervals no greater than 15 m (50 ft).

Photo 1 Photo 2
Key Point #3 – Sediment Control
Fiber rolls are acceptable for use as sediment control and may be used in conjunction with other soil stabilization methods (soil binders, mulches, et c.) (Photo 3) and/or other sediment controls.

Key Point #4 – Removal
Fiber rolls are typically left in place. If they are re moved, dispose of the accumulated sediment and fill in trenches, holes, or depressions to blend in with adjacent ground contours. 41 EXHIBIT A
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Fiber Rolls SC-5
Key Point #5 – Inspection and Maintenance
Inspect fiber rolls prior to and after rain events, a nd at least daily during prolonged rainfall. Maintenance includes replacing slumping rolls, removing accumulated sed iment, and filling in rills. If fiber rolls split, tear (Photo 4), unravel, or become ineffective, replace them immediately.

Photo 3 Photo 4
Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Runoff flows under the fiber roll or daylight shows
under fiber roll.

Trench-in rolls to a depth of 100 mm (4 in) and stake. Place compacted soil along the uphill side of the fiber roll.

Runoff flows along fiber roll and discharges
around ends.

Make sure rolls are placed on a level contour and turn ends of fiber rolls up-slope.

Runoff flows between fiber rolls. Ensure that fiber rolls are butted tightly together and staked.

There is excessive sediment accumulation. Remove accumulated sediment. Apply soil stabilization measures to contributing areas.

Length of slope draining to fiber roll is too long. Place fiber rolls at shorter intervals. The steeper the slope, the closer together the fiber rolls should be placed.
42 EXHIBIT A
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Gravel Bag Berm SC-6
43 SC-6 GRAVEL BAG BERM
A gravel bag berm consists of a single row of gravel bags that are installed end-to-end to form a barrier across a slope to intercept runoff, reduce runoff velocity, release runoff as sheet flow, and provide some sediment removal.

Applications
Along the top, face, and at grade breaks of exposed and erodible slopes Key Points
Key Point #1 – Installation
Proper gravel bag berm installation is crucial to ensure its effectiveness and performance. Gravel bag berms should be placed on a level contour along the slope (Photo 1). Gravel bags should be tightly abutted together and not overlapped (Photo 2).

Photo 1 Photo 2
Key Point #2 – Bag Design
Bags should be made of a woven polypropylene, polyethylene or polyamide fabric, or burlap material.

When full, a bag should be 450 mm (1.5 ft) long, 300 mm (1 ft) wide, and 75 mm (3 in) thick, with a mass of approximately 15 kg (35 lb). Bag dimensions are standardized but may vary based on locally available materials. Alternative bag sizes shall be subm itted to the Resident Engineer for approval prior to deployment. Fill material shall be 13 mm to 25 mm (1/2 in to 1 in) class 2 aggregate base that is clean and free from clay and undesirable materials.

Key Point #3 – Sediment Control
Although gravel bag berms remove some sediment, they should not be used in place of linear sediment barriers.

Key Point #4 – Limitations
Gravel bags are sensitive to ultraviolet light resulting in a limited durability that may make them unsuitable for long-term projects. Gravel bag berms are labor intensive. Installation, removal, and maintenance costs should be evaluated when considering this BMP.

Key Point #5 – Inspection and Maintenance
Inspect gravel bag berms weekly and prior to and af ter rainfall events during the rainy season. Repair or replace broken or ripped bags, and reshape as necessar y. Remove accumulated sediment when it reaches 1/3 the height of the berm. Repair washouts and rills as needed.

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Gravel Bag Berm SC-6
Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Runoff flows under the bags.

Ensure that bags are placed completely on the soil surface and not overlapped. Butt the bag ends together tightly.

Repair rills and washouts.

Runoff flows around ends of bag rows. Make sure that bags are placed on a level contour. Turn up ends of each row.

Runoff flows between bags. Ensure that gravel bags are butted tightly together.

There is excessive sediment accumulation. Remove accumulated sediment. Apply soil stabilization measures to contributing areas
Length of slope draining to gravel bag berm is too
long.

Place berm at shorter intervals. The steeper the slope, the closer together the berms should be placed.
44 EXHIBIT A
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Street Sweeping and Vacuuming SC-7
SC-7 STREET SWEEPING AND VACUUMING
Street sweeping and vacuuming are practices to remove tracked sediment from public roads in order to prevent sediment and dirt from entering storm drains or receiving waters. Areas of concern include ingress and egress points, portions of roadway within the project limits adjacent to a freeway or other public road, and any other paved surface within project limits that is to remain after construction is complete.

Applications
Where sediment is tracked onto public or private roadways from the project site Key Points
Key Point #1 – Sweepers
Sweepers should have vacuum or other mechanical attachments for collecting dirt and sediment (Photo 1). Adjust brooms regularly to maximize efficiency of sweeping operations. Never use kick brooms or sweeper attachments for the implementation of this BMP.

Key Point #2 – Inspection
Inspect project ingress and egress points and roadways daily for signs of tracked sediment (Photo 2).

Photo 1 Photo 2
Key Point #3 – Sweeping Waste Disposal
After sweeping is finished, properly dispose of sweeper waste. Sweeper waste that includes trash and debris should be disposed of at an approved dumpsite. For collected sediment that is free of trash and debris, consider incorporating the sediment b ack into the project’s earthwork operations.

Key Point #4 – Site Entrances and Exit
Designate a limited number of centralized ingress/egress locations for the site and instruct construction personnel to use only those locations for entering/exiting the project (see TC-1). 45 EXHIBIT A
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Street Sweeping and Vacuuming SC-7
Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Sediment tracking is excessive. Install a stabilized construc tion entrance/exit at egress point.

Sweeper is not picking up sediment. Adjust sweeper brooms to maximize efficiency of sweeping operations.

Sweeping causes excessive dust.

Use a sweeper with a vacuum attachment. Use sweeper
with water spray device to reduce dust. Never use kick
brooms or sweeper attachments.

Sediment is being tracked from many areas of the
job site.

Limit egress and ingress locations and instruct personnel to use designated centralized entrance/outlet locations.
46 EXHIBIT A
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Sandbag Barrier SC-8
SC-8 SANDBAG BARRIER
A sandbag barrier is a temporary linear sediment barrier constructed of stacked sandbags. This type of barrier is designed to intercept and slow storm wa ter sheet flow runoff. Sandbag barriers allow sediment in runoff to settle before the water leaves the construc tion site. Sandbag barriers can also be used to divert and detain moderately concentrated flows associated with ditches, swales, and storm drain inlets.

Applications
Along the perimeter of a site
Below the toe of slopes as required
Down slope of exposed soil areas
Around temporary stockpiles as required
Parallel to a roadway to keep sediment from paved areas To divert or direct flow
Key Points
Key Point #1 – Installation
When used as a linear sediment barrier for slopes, sandbags should be placed along a level contour with the end of each row turned up-slope to prevent fl ow around the ends. Due to the limited sediment holding capacity behind the bags, they should be used in conjunction with other erosion source controls such as soil binders, covers, and/or mulches to provide effective control.

Key Point #2 – Setback
A sandbag barrier should be placed with a setback of at least 1 m (3 ft). Where a 1 m (3 ft) setback is not practicable due to site conditions, the barrier may be constructed at the toe of slope but should be placed as far from the toe as practicable to increase th e ponding area and allow sediment to settle out.

Key Point #3 – Configuration
Sandbags should be stacked in a pyramid formation (Photo 1). To do this, the base of the barrier should be the widest, with the width decreasing with each higher row. The joints between bags should be staggered for each row.

Photo 1
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Sandbag Barrier SC-8
Key Point #4 – Cross Barriers
For sandbag barriers not on a level contour and for longe r reaches, install cross barriers at a minimum of 150 m (500 ft) intervals to prevent concentrated flow.

Key Point #5 – Limitations
Sandbag materials are sensitive to ultraviolet light resulting in a limited durability that may make them unsuitable for long-term projects. Sandbag barriers ar e labor intensive. Installation, removal, and maintenance costs should be evaluated when considering this BMP.

Key Point #6 – Inspection and Maintenance
Inspect sandbag barriers weekly and prior to and afte r rainfall events during the rainy season. Repair or replace broken or ripped bags, and reshape as necessar y. Remove accumulated sediment when it reaches 1/3 the barrier height. Repair washouts and rills as needed. When no longer needed, remove the barrier and accumulated sediment then clean, re-grade, and stabilize the area.

Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

There is excessive sediment accumulation.

Remove sediment. Apply Hydraulic Mulch (SS-3) or Straw
Mulch (SS-6) or other soil stabilization BMP upstream to reduce sediment in runoff.

Concentrated flows causes erosion to occur behind
barriers. Place cross barrier check dams behind the barrier.

Length of slope draining to sandbag barrier is too
long. Slope shall be 61 m (200 ft) or less. Shorten slope length using Fiber Rolls (SC-5) or equivalent.

Storage capacity is inadequate due to sediment
buildup.

Remove accumulated sediment when it reaches 1/3 the
barrier height.

There is insufficient ponding area.

Sandbag barrier should be installed with at least a 1 m (3 ft) setback from the toe of slope wh ere possible. Divert flow at top of slope.

Erosion occurs around barrier ends. Turn ends of barriers into the up-slope area.

Sandbag barrier is not installed along level enough
contour.

Reinstall barrier so that change in elevation does not exceed 1/3 the barrier height along its reach or install cross barriers.

Slope draining to barrier is too steep. Slope shall be
less than 1:1 (V:H).

Shorten slope length using Fiber Rolls (SC-5) or equivalent.

Increase setback of sandbag barrier from the toe of slope.

Incorrect sandbag material, size or fill material is
being used.

Require the contractor to use th e specified bag material, size, and fill material.

Sandbags rupture or degrade. Replace bags. Clean up and remove any spilled material.

Cross barriers are not installed or are installed
incorrectly.

Place cross barriers on the receiving side of the barrier at a maximum separation of 150 m (500 ft). Cross barrier should be a minimum of 1/2 and a maximum of 2/3 the barrier
height.
48 EXHIBIT A
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Straw Bale Barrier SC-9
SC-9 STRAW BALE BARRIER
A straw bale barrier is a temporary linear sediment barrier constructed of straw bales. This type of barrier is designed to intercept and slow storm water runoff. Straw bale barriers allow sediment in runoff to settle before water leaves the construction site.

Applications
Along the perimeter of a site
Below the toe of slopes as required
Down slope of exposed soil areas
Around temporary stockpiles as required
Key Points
Key Point #1 – Installation
When used as a linear sediment barrier for slopes, straw bales should be placed along a level contour with the end of each row turned up-slope to prevent fl ow around the ends. Bales should be installed in a shallow trench with ends tightly abutted together.

Key Point #2 – Setback
Straw bales placed at the toe of slopes should be set b ack at least 1 m (3 ft) from the toe. Where a 1 m (3 ft) setback is not practicable due to site conditions, th e barrier may be constructed at the toe of the slope but should be placed as far from the toe as practicab le to increase the ponding area and allow sediment to settle out.

Key Point #3 – Configuration
Straw bales should be placed in two rows back to back with a half-bale offset to cover the butted ends of the bales.

Key Point #4 – Cross Barriers
For straw bale barriers not on a level contour and for longer reaches, install cross barriers at a minimum of 150 m (500 ft) intervals to prevent concentrated flow.

Key Point #5 – Application Limitations
Straw bale barriers should not be used in areas subj ect to highly concentrated flows (Photo 1) such as channels or live streams as they may be easily overtak en or washed away. Straw bale barriers should not be used on paved surfaces, in lined ditches, or for drain inlet protection. Consider using sandbag barriers instead.

Photo 1
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Straw Bale Barrier SC-9
Key Point #6 – Durability Limitations
Straw bales fall apart when removed or degrade when left in place for extended periods. They can be labor intensive to install, remove, and maintain.

Key Point #7 – Inspection and Maintenance
Inspect straw bale barriers weekly and prior to and af ter rainfall events during the rainy season. Repair or replace broken or damaged bales as necessary. Remove accumulated sediment when it reaches 1/3 the barrier height. Repair washouts or other damage as needed or required. When no longer needed, remove barrier and accumulated sediment then cl ean, re-grade, and stabilize the area.

Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

There is excessive sediment accumulation.

Remove sediment. Apply Hydraulic Mulch (SS-3) or Straw
Mulch (SS-6) or other BMP upstream to reduce sediment in runoff.

Concentrated flows causes erosion to occur behind
barriers
Place cross barrier check dams behind the barrier. Make sure the barrier is along a level contour. Ensure that stakes are angled toward adjacent bales so that they are held down together.

Bottom of barrier is not properly keyed in . Trench and replace bales and backfill.

Length of slope draining to barrier is too long.

Slope shall be 30 m (100 ft) or less. Shorten slope length using Fiber Rolls (SC-5) or equivalent.

Storage capacity is inadequate due to sediment
buildup.

Remove accumulated sediment when it reaches 1/3 the
height of the barrier.

There is insufficient ponding area.

Barrier should be installed with at least a 1 m (3 ft) setback from the toe of slope where possible. Divert flow at top of slope.

Erosion occurs around barrier ends. Turn ends of barriers into the up-slope area.

Bale binding degrades and breaks. Replace degraded bales. Place bales so that the bindings are parallel to the ground.

Barrier is not installed along level enough contour. Reinstall barrier so that change in elevation does not exceed 1/3 the barrier height along its reach or install cross barriers.

Slope draining to straw bale barrier is too steep.

Slope shall be less than 1:10 (V:H).

Shorten slope length to 15 m (30 ft) or less using Fiber Rolls (SC-5) or equivalent. Increase setback of barrier from the toe of slope.

Straw bale barrier is installed in concentrated flow
area.

Replace straw bale barrier with proper BMP such as Check Dams (SC-4), if appropriate.

Cross barriers are not installed or are installed
incorrectly.

Place cross barriers on the receiving side of the barrier at a maximum separation of 150 m (500 ft). Cross barrier should be a minimum of 1/2 and a maximum of 2/3 the barrier
height.
50 EXHIBIT A
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Storm Drain Inlet Protection SC-10
SC-10 STORM DRAIN INLET PROTECTION
Storm drain inlet protection is a practice to redu ce sediment from storm water runoff discharging from the construction site prior to entering the storm drain sy stem. Effective storm drain inlet protection allows sediment to settle out of water or filters sediment fro m the water before it enters the drain inlet. Storm drain inlet protection is the last line of sediment control defense prior to storm water leaving the construction site.

Applications
Where storm water surface runoff can enter a drain inlet Where disturbed drainage areas have not yet been permanently stabilized Where ponding will not encroach into traffic
Where the drainage area is 4 ha (10 ac) or less
Key Points
Key Point #1 – Identify Drain Inlets
Identify existing and/or planned storm drain inlets th at have the potential to receive storm water runoff and discharge from the construction site. For those drai n inlets that are to be protected, determine the most effective method to use. Consider drain inlet protection for active inlets that are downstream of DSAs.

Key Point #2 – Sandbag Barriers
A sandbag barrier (Photo 1) is the most common type of protection due to the flexibility of its use.

Sandbag barriers are constructed by placing the bags around the inlet to create a holding area that allows suspended sediment to settle.

Photo 1
Key Point #3 – Filter Fence
A filter fabric fence (Photo 2) is effective in open areas where sheet flows are low and are not expected to exceed 0.14 m3
/s (0.5 cfs). Filter fabric fences are installed similarly to silt fences but are constructed to surround the inlet to create an enclosure. Use plastic sheeting or geotextile blankets to stabilize any DSAs within the enclosure to prevent sediment within the enclosed area from entering the inlet. 51 EXHIBIT A
Tuesday, October 07, 2025 Reg CC MTG, Page *300
Storm Drain Inlet Protection SC-10
Photo 2
Key Point #4 – Sediment Traps
Excavated drop inlet sediment traps are typically u sed where relatively heavy flows are expected and overflow capacity is needed. A drain inlet sedimen t trap is constructed by excavating the soils surrounding the inlet to create a temporary trap that detains flows and allows suspended sediments to settle before storm water is discharged from the site.

Key Point #5 – Inspection
Inspect all inlet protection devices before and afte r storm events, at 24 hour intervals during extended storms, and weekly during the rest of the rainy season. Check storm drain inlet after several storms to determine if sediment is bypassing inlet protection devices.

Key Point #6 – Maintenance
Maintenance is critical to ensure that drain inle t protection remains functional. Remove accumulated sediment when it reaches 1/3 the barrier height or 1/3 the holding capacity. For barriers, replace broken or torn bags. For fences, repair/replace fencing ma terial and re-stake fences that are damaged.

Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Excessive sediment is entering the inlet.

Ensure that soil stabilization and sediment control devices are installed upstream of inlets. Ensure that the barriers around the inlet are installed correctly. Sandbags need to be tightly abutted. Filter fence needs to be keyed in so that water goes through filter fabric and not under it. Ensure that disturbed soil inside the protective device is prevented from entering drain by covering with plastic.

Material from broken bags is entering inlet. Clean out inlet. Remove broken bags and replace as necessary.

Ponded water causes a traffic concern. Use alternative BMPs upstream. Remove drain inlet protection if necessary.
52 EXHIBIT A
Tuesday, October 07, 2025 Reg CC MTG, Page *301
Wind Erosion Control WE-1

WIND EROSION CONTROL
WE-1 WIND EROSION CONTROL
Wind erosion control consists of applying water or other dust palliativ es to prevent or alleviate dust nuisance. Dust control shall be applied in accordance with Caltrans standard practices.

Applications
On all exposed soils that are subject to wind erosion
Key Points
Key Point #1 – Dust Control Operation
Care should be taken when applying water (Photo 1) or palliative to prevent the washing of sediment offsite or into storm drains or receiving waters. Do not apply so much that runoff occurs.

Photo 1
Key Point #2 – Stockpile and Small Area Management
Cover small stockpiles or small DSAs as an alternative to applying water or dust palliative.

Key Point #3 – Palliative Application Rates
When applying palliatives or binders as a wind er osion control, refer to the manufacturer’s recommendations for guidance.

Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Excessive dust leaves the site. Increase frequency of water application. Consider using a palliative or binder on inactive areas.

Vehicles kick up dust. Water more frequently. Limit vehicle speeds. Stabilize the roadway.

Watering for dust control causes erosion
Reduce water pressure on the water truck. Check watering equipment to ensure that it has a positive shutoff. Water less frequently.

Sprayed areas are ineffective at limiting dust. Re-spray areas and ensure that the application rate is proper. 53 EXHIBIT A
Tuesday, October 07, 2025 Reg CC MTG, Page *302
Stabilized Construction Entrance/Exit TC-1

TRACKING CONTROL
TC-1 STABILIZED CONSTRUCTION ENTRANCE/EXIT
Stabilized construction access is a defined point of entran ce/exit to a construction site that is stabilized to reduce the tracking of sediment (mud and dirt) onto public roads by construction vehicles. Stabilized construction entrances are an effective method for reducing tracking of sediment from the construction site.

Applications
As a preventive method instead of a treatment method (e.g., sweeping or dust control) Where dirt or mud can be tracked onto public roads
Adjacent to water bodies
Where poor soils are encountered
Key Points
Key Point #1 – Design
Site conditions may dictate the design and need for access points. Design a stabilized construction entrance/exit to support the heaviest vehicles and equipment that will use it (Photo 1). The access point should be at least 15 m (50 ft) in length or four times the circumference of the largest construction vehicle tire, whichever is greater (Photo 2). Designate access points and require all employees, subcontractors, and others to use them.

Photo 1 Photo 2
Key Point #2 – Grading
Grade construction entrance/exit points to prevent r unoff from leaving the construction site. Route runoff from entrances/exits through a sediment-trapping device before discharge.

Key Point #3 – Aggregate Characteristics
Stabilize the roadway with aggregate, AC, or PCC, depending on expected usage and site conditions.

When access points are constructed from aggregate, aggregate should be 75 mm (3 in) to 150 mm (6 in) in diameter and at least 300 mm (1 ft) in depth. Place aggregate over a geotextile fabric.

Key Point #4 – Alternative Stabilization Methods
Alternative stabilization methods such as manufactured steel plates (Photo 3) or steel pipes/gratings require written approval of the Resident Engineer. The use of cold mix asphalt or AC grindings is not allowed.
54 EXHIBIT A
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Stabilized Construction Entrance/Exit TC-1
Key Point #5 – Inspection and Maintenance
Inspect and maintain stabilized construction entr ance/exit points. Routinely check for damage and effectiveness (Photos 4 and 5). Remove accumulated sediment (Photo 6) and/or replace stabilization material as needed.

Photo 3 Photo 4
Photo 5 Photo 6
Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Access points require constant maintenance. Select proper stabilization mate rial or consider alternate methods for longevity, performance and site conditions.

Stabilization material (aggr egate) is tracked onto
roadway.

Limit larger vehicles from construction exit or use larger diameter material.

Aggregate material is being inco rporated into soil. Use geotextile fabric under base material.

Excessive sediment is tracked onto roadway. Increase length of stabilized exit. Regularly maintain access area to remove sediment buildup.

Sediment-laden water is leaving the construction
site.

Properly grade access point to prevent runoff from leaving site. Route runoff through a sediment-trapping device.

Sediment is being tracked from numerous
locations.

Limit access points and require their use. Stabilize
designated access points.
55 EXHIBIT A
Tuesday, October 07, 2025 Reg CC MTG, Page *304
Stabilized Construction Roadway TC-2
TC-2 STABILIZED CONSTRUCTION ROADWAY
A stabilized construction roadway is a temporary access road that connects existing public roads to remote construction areas. For storm water protection, it should be designed to control dust and erosion created by vehicular traffic.

Applications
Where displacement of soil occurs because of vehicular traffic during wet weather Where dust control is a problem during dry weather
Adjacent to water bodies
Where poor soils are encountered
Key Points
Key Point #1 – Design
Site conditions may dictate the design and need for stabilized construction roadways. Design the roadway to support the heaviest vehicles and equipment that will use it. Grade the road way to prevent runoff from leaving the construction site. This may require the c onstruction of a drainage ditch to collect and convey runoff.

Key Point #2 – Stabilization Materials
Stabilize the roadway with aggregate, AC, or concre te, depending on expected usage and site conditions.

Aggregate diameter should be between 75 mm (3 in) and 150 mm (6 in) and at least 300 mm (1 ft) in depth. Place aggregate over a geotextile fabric. The use of cold mix asphalt or AC grindings is not allowed.

Key Point #3 – Inspection and Maintenance
Inspect and maintain the stabilized construction roadway routinely. Re-grade the roadway as necessary.

Check for damage and repair as necessary or as directed by the Resident Engineer.

Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Runoff leaves the site via the roadway. Properly grade roadway so that runoff is kept on site. Install a drainage ditch along roadway to convey flows.

Roadway degrades or breaks up.

Re-grade roadway using material that will support the
heaviest vehicles that will use the road. Stabilize roadway with AC, concrete base, aggregate, or equivalent.

Vehicles kick up dust. Re-stabilize the roadway.
56 EXHIBIT A
Tuesday, October 07, 2025 Reg CC MTG, Page *305
Water Conservation NS-1

NON-STORM WATER MANAGEMENT
NS-1 WATER CONSERVATION
Water conservation involves the use of practices that reduce the amount of water used for a given activity.

If less water is used, the potential for erosion decreases and the transport of construction-related pollutants offsite is less likely.

Applications
On all projects where water is used during the course of construction Key Points
Key Point #1 – Watering Equipment
Watering equipment should be kept in good working order (Photo 1). Repair leaky watering equipment promptly.

Photo 1
Key Point #2 – Equipment Washing
Discourage the washing of vehicles and equipment on the construction site. Workers should never wash their personal vehicles on site. Vehicles and equipment th at regularly leave the construction site should be washed offsite.

Key Point #3 –Paved Areas
Paved areas should be swept and vacuumed rather than washed off. Always protect storm drain inlets or receiving waters from sediment or other pollutants suscep tible to non-storm water run-off. When possible, direct runoff water to areas where it can percolate into the ground.

Key Point #4 – Dust Control
When watering for dust control, ensure that watering operations do not cause erosion. 57 EXHIBIT A
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Water Conservation NS-1
Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Water tank leaks from the outlet valve. Repair the positive shutoff valve.

Watering equipment overflows during filling
creating muddy and rutted areas.

Do not overfill. Use other BMPs to stabilize the roadway around the filling area e.g. Stabilized Construction Roadway (TC-2).

Paved areas are being washed with water. Sweep and vacuum paved areas per Street Sweeping and Vacuuming BMP (SC-7).

Watering for dust control causes erosion. Apply soil stabilization or dust palliative to slopes and reduce water frequency.
58 EXHIBIT A
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Dewatering Operations NS-2
NS-2 DEWATERING OPERATIONS
This BMP is intended to prevent the discharge of pollutants from construction site dewatering operations associated with storm water (accumulated rain ) and non-storm water (groundwater, water from a diversion or cofferdam, etc.). Dewatering effluent that is discharged from the construction site to a storm drain or receiving water is subject to the requireme nts of the applicable National Pollutant Discharge Elimination System (NPDES) permit. Refer to the Caltrans Field Guide to Construction Site Dewatering for detailed guidance for management of dewatering operations. The District Construction Storm Water Coordinator is also available for assistance.

Applications
On all projects where the discharge of wa ter is to occur by mechanical means Key Points
Key Point #1 – Management Alternatives
If possible, the contractor should consider managing dewatering without discharge to a storm drain or receiving water. Options include: (1) retaining the wate r on site for construction use or allowing water to evaporate/infiltrate, (2) discharging to the sanitary sewer with permission from the local agency; (3) discharging to an adjacent land or facility with permission of the owner, and (4) having the effluent transported and disposed of offsite using a Transportation, Storage & Disposal (TSD) contractor. If one of these management options is used, the water is not di scharged to a storm drain or receiving water, and the operation is not subject to an NPDES permit.

Key Point #2 – Notify CSWC
If on-site management of the dewa tering operation is not the selected option, contact the Construction Storm Water Coordinator (CSWC) befo re the dewatering operation commences.

Key Point #3 – Dewatering Under the Caltrans General NPDES Permit In many areas of the state, uncontaminated storm water and minor discharges of non-storm water can be discharged to a storm drain or receiving water under the Caltrans General NPDES Permit. If the effluent is not visibly clear, it must be treated to remove sediment prior to discharge (Photo 1). All records related to the dewatering operation must be maintained w ith the project SWPPP and provided to the Regional Water Quality Control Board (RWQCB) upon request. No te that in RWQCB Region 1 and 2, no type of dewatering discharge to a storm drain or receiving water is authorized under the Caltrans NPDES Permit – a separate Regional dewatering permit is required.

Key Point # 4 – Dewatering Under a Regional Dewatering Permit For all dewatering discharges in RWQCB Regions 1 and 2 (North Coast and San Francisco Bay areas), and for many discharges of non-storm water dewateri ng (Photo 2) in all other Regions, the RWQCB must approve a discharge to a storm drain or receiving water. The RWQCB may require the contractor to apply to discharge under a separate Regional dewatering pe rmit or under a site-specific dewatering permit.

Regional dewatering permits generally require the contractor to monitor (test) the dewatering effluent, to maintain monitoring records, and to submit re ports to the RWQCB about the operation. Discuss dewatering requirements with the District Construction Storm Water Coordinator. 59 EXHIBIT A
Tuesday, October 07, 2025 Reg CC MTG, Page *308
Dewatering Operations NS-2
Photo 1 Photo 2
Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Discharge of treated water causes erosion. Install outlet protection or velocity dissipation device (SS-10).

Treatment unit fills with sediment. Remove sediment when unit reaches 1/3 its capacity to preserve settling efficiency.

Dewatering discharge flow is higher than
expected.

Alter the treatment unit to handle increased flow. Notify the RWQCB and District Construction Storm Water
Coordinator of the increased flow before resuming
dewatering operation.

Water spread on the construction site is not
infiltrating fast enough and is entering the storm
drain system or receiving water.

Stop dewatering. Install a sediment treatment system and test discharge as necessary.
60 EXHIBIT A
Tuesday, October 07, 2025 Reg CC MTG, Page *309
Paving and Grinding Operations NS-3
NS-3 PAVING AND GRINDING OPERATIONS
Paving and Grinding Operations include the handling of materials and wastes and the use of equipment associated with pavement preparation, paving, gri nding, removal, surfacing, resurfacing, thermoplastic striping, and placing pavement markers.

Application
During pavement grinding and removal
During PCC paving
During AC paving and resurfacing
During placement of thermoplastic striping and pavement markers Key Points
Key Point #1 – Asphalt Concrete (AC)
Remove or dispose of grindings and wastes as work progresses. Place AC pieces in embankments above the water table and cover with plastic until they are removed from the site. Remove wastes from the site immediately.

Key Point #2 – AC Equipment
Coat AC equipment with non-toxic non-foaming produc ts. Clean equipment (Photo1) offsite whenever possible. When paving equipment is kept onsite, pl ace paving equipment on plastic sheeting to capture drips or leaks (Photo 2). Dispose of hardened AC properly.

Photo 1 Photo 2
Key Point #3 – Wastes
Do not allow wastes, such as AC pieces, PCC gri nding residue/slurry (Photo 3), sand/gravel, exposed aggregate concrete residue, or dig-out materials in to storm drains or receiving waters. Sweep, vacuum, and collect such wastes and recycle or dispose of properly.

Key Point #4 – Seal Coats
Do not apply seal coat, tack coat, slurry seal, or fog seal if rain is predicted during the application or curing period. Do not conduct digout operations in the rain. During application of seal coat, tack coat, slurry seal, or fog seal, cover drainage inlets and ma nhole covers with filter fabrics. Do not apply these materials in the rain.
61 EXHIBIT A
Tuesday, October 07, 2025 Reg CC MTG, Page *310
Paving and Grinding Operations NS-3
Photo 3
Key Point #5 – Thermoplastic Striping
Verify that equipment shut-off valves function properly to avoid thermoplastic leakage. Do not pre-heat, transfer, or load thermoplastic near storm drains or receiving waters. When filling the pre-heater, leave 150 mm (6 in) of space at the top of the container to prevent spills when the equipment is moved. Clean truck beds daily and recycle thermoplastic material when possible.

Key Point #6 – Raised/Recessed Pavement Markers
Do not transfer or load bituminous materials near storm drains or receiving waters. Verify that all pressure is released before filling melting tank. When filling the melting tank, leave 150 mm (6 in) of space at the top of the container to prev ent spills when the equipment is moved.

Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Paving equipment leaks while parked.

Clean up spilled or leaked material. Place drip pans, plastic sheeting or absorbent materials under parked equipment
when not in use.

Loose gravel and sand deposit on roadway from
paving operations.

Sweep streets when practical. Minimize washing. If
washing is necessary, protect inlets and receiving waters during operations.

Water residue from grinding and saw cutting
operations enters inlet.

Clean inlet and recover as much material as possible. Use a vacuum attachment to capture concrete slurry residue.

Block inlet. Notify the District Construction Storm Water Coordinator about the potential for a non-compliant
incident.

Seal coat, tack coat, and fog seal wash off streets.

Allow for proper curing time before rain events. Do not apply before or during predicted rainfall. Protect drain inlets.

Operators use diesel fuel to clean equipment. Use only non-toxic substances to coat and clean paving and transport equipment.

Seal coat, tack coat, and fog seal enter inlets.

Clean inlets and collect as much material as possible. Cover inlets with filter fabric. Notify the District Construction Storm Water Coordinator about the potential for a noncompliant incident. 62 EXHIBIT A
Tuesday, October 07, 2025 Reg CC MTG, Page *311
Temporary Stream Crossing NS-4
NS-4 TEMPORARY STREAM CROSSING
A temporary stream crossing is a structure placed acro ss a waterway that allows construction traffic to cross without contacting the water. Typical types include culvert crossings, ford crossings, and bridge crossings. Temporary stream crossings prevent str eambed erosion and downstream sedimentation due to construction traffic.

Applications
Where appropriate permits have been secured
Where construction equipment or vehicles must cross a waterway (ephemeral or perennial) Key Points
Key Point #1 – Permits
Verify that applicable permits have been obtained before the stream crossing is installed. Required permits may include RWQCB 401 Certification, U.S. Army Corps of Engineers 404 Permit, and/or Department of Fish and Game 1601 Agreement. Ve rify that applicable pre-installation water sampling/testing has been completed before, and possibly during, installation.

Key Point #2 – Design
Verify that the structure design has been prepared unde r the direction of and approval of a registered civil and/or structural engineer. The structure should not constrict waterway flow such that backups or washouts occur during flood events. Culverts are accepta ble for perennial or intermittent streams and can accommodate heavy equipment loads. Fords are the least expensive but are acceptable only for dry washes/ephemeral streams during the dry season. Bridges (Photo 1) are the most expensive but are appropriate for high velocity/steep gradient streams or where restrictions in the waterway channel are not allowed.

Photo 1
Key Point #3 – Installation
Construct crossings during the dry season. Stabilize adjacent construction roadways, work areas, and streambeds to prevent erosion. Minimize disturbance or removal of adjacent vegetation. If riparian vegetation is disturbed for construction of the stream crossing, the vegetation should be cut no lower than ground level and covered with a layer of clean river cobble. 63 EXHIBIT A
Tuesday, October 07, 2025 Reg CC MTG, Page *312
Temporary Stream Crossing NS-4
Key Point #4 –- Use
Vehicles are not to be operated, stored, fueled, or main tained in wet or dry portions of a waterway without authorization of the Resident Engineer or as authorized by the Fish and Game Permit. Drip pans must be placed under all vehicles/equipment on temporary stream crossing structures that remain idle for more than one hour. Being in such close proximity to a watercourse, this BMP, and others implemented with it, must be installed correctly and maintained to prevent any discharge. Any incident of discharge requires submittal of a Notice of Non-Compliance.

Key Point #5 – Inspection and Maintenance
Inspect temporary stream crossings weekly and afte r significant rain events for water flow blockage, sediment buildup, trapped debris, structural damage, ri prap displacement, or streambed erosion. Verify that sediment buildup is removed regularly and that riprap/aggregate is replaced as needed to prevent erosion and maintain stability of adjacent areas.

Key Point #6 – Removal
Ensure that temporary stream crossings are rem oved promptly when no longer needed. Remove river cobble from disturbed riparian vegetation to ensure rapid re-growth.

Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Slopes of temporary earthen crossing erodes. Place rock layer on slope sides. Stabilize roadway at crossing.

Sediment and debris block culvert inlet. Remove sediment and debris as necessary to keep pipe open.

Pipe outlet causes erosion. Stabilize outlet with riprap or flared end section.

Overtopping occurs. Incorrect design. Redesign crossing and obtain approval (stamp) of registered civil and/or structural engineer. 64 EXHIBIT A
Tuesday, October 07, 2025 Reg CC MTG, Page *313
Clear Water Diversion NS-5
NS-5 CLEAR WATER DIVERSION
A clear water diversion is a system of structures that intercepts surface water from a running stream or waterway upstream of a project, transports it around the construction site, and discharges it downstream of the site, with minimal water quality impacts. Typical structures used for clear water diversions include diversion ditches, berms, dikes, slope drains, coffer dams, pipes, and drainage and interceptor swales.

Applications
Where appropriate permits have been secured
Where work must be performed in an active drainage system, a running stream, or a water body Key Points
Key Point #1 – Permits
Verify that applicable permits have been obtained be fore the diversion is installed. Required permits may include RWQCB 401 Certification, U.S. Army Corps of Engineers 404 Permit, Department of Fish and Game 1601 Agreement, and/or Federal Emergency Ma nagement Agency requirements. If required by a permit, verify that applicable pre-installation wa ter sampling/testing has been completed before, and possibly during, installation.

Key Point #2 – During Design
The structure should not constrict waterway flow such that backups or washouts occur due to fluctuations in water depth or flow volume. Materials used to c onstruct diversion structures must be free of potential pollutants such as soil, silt, sand, clay, grease, or oil. At all times during construction, operation, maintenance, and removal, sufficient water flow/ volume must be diverted to maintain downstream aquatic life (Photo 1).

Photo 1
Key Point #3 – During Construction
When possible, construct diversion structures during periods of low or no stream flow. Minimize disturbance and removal of adjacent vegetation. If ripa rian vegetation is disturbed for construction of the diversion, the vegetation should be cut no lower than ground level and covered with a layer of clean river cobble. The exterior of vehicles and equipment in we t areas of the diversion construction site should be free of petroleum residues and sealed so as to prevent leakage of fuels and oils into the water body if submerged. Only the bucket of an excavator/backhoe may operate in a water body. The main body of the equipment is not to enter the water portions of th e water body except to cross the stream to access the work site.
65 EXHIBIT A
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Clear Water Diversion NS-5
Key Point #4 – Operation
Barriers should be installed to prevent muddy wate r from flowing from adjacent construction activity to the stream. Drip pans must be placed under all st ationary equipment and vehicles located over water diversions that remain idle for more than one hour. Being in such close proximity to a watercourse, this BMP, and others implemented with it, must be installed correctly and maintained to prevent any discharge. Any incident of discharge requires submittal of a Notice of Non-Compliance.

Key Point #5 – Inspection and Maintenance
Inspect diversion structures weekly and after significant rain events for damaged linings, sediment buildup, trapped debris, or reduced slope protection. Ensure that debris is removed and linings are repaired promptly.

Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Vehicles and equipment parked over water bodies
leak fluids.

Place drip pans under all vehicl es and equipment that are placed on structures over water bodies that will be idle for more than one hour.

Erosion occurs along diversion path. Protect diversion from erosion. Use rock, gravel, pipe or other BMP to protect diverted waterway.
66 EXHIBIT A
Tuesday, October 07, 2025 Reg CC MTG, Page *315
Potable Water/Irrigation NS-7
NS-7 POTABLE WATER/IRRIGATION
Non-storm water discharges that originate from onsite and offsite sources must be properly managed to reduce the potential for pollutants being discharged from the construction site. Sources of these non-storm waters include broken water lines, landscape irrigati on, lawn watering, water line flushing, and fire hydrant flushing.

Applications
All projects susceptible to the above-listed and ot her non-storm water discharges from the construction site
Key Points
Key Point #1 – Divert Flows
Where possible, direct potable/irrigation water or iginating from offsite sources around the construction site or through the site in a way that mi nimizes contact with construction activities.

Key Point #2 – Onsite Irrigation
Inspect irrigated areas on the construction site for excessive watering (Photo 1). Adjust watering schedules to ensure landscaping receives adequate wa ter but minimizes associated runoff. Promptly shut off water to broken lines, sprinklers, or valves and repair as needed.

Photo 1
Key Point #3 – Water Conservation
Reuse water from line flushing for landscape irrigation.

Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Irrigation line breaks and causes erosion.

Shut off water to broken lines. Protect downstream drain inlets or receiving waters by implementing sediment control BMPs. Repair or replace lines and repair erosion.

Water from irrigation operations causes runoff or
erosion.

Adjust watering schedule and times. Turn off sprinklers when they are no longer necessary to maintain vegetation.

Ensure that the irrigation system is operating correctly by verifying that sprinklers are directed appropriately and are not broken or leaking.

Discharge from line flushing causes erosion. Discharge water into a stabilized area or temporary sediment trap. Reuse water when practical.
67 EXHIBIT A
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Vehicle and Equipment Cleaning NS-8
NS-8 VEHICLE AND EQUIPMENT CLEANING
Wash water from vehicle and equipment cleaning is not to be discharged from construction sites because the rinse water may contain contaminates such as sed iment, petroleum/lubricant residues, soaps, or solvents that could enter storm drain systems or receiving waters.

Applications
All construction sites
Key Points
Key Point #1 – Offsite Cleaning
Equipment/vehicle cleaning should be conducted offsite. All vehicles that regularly enter and leave the construction site must be cleaned offsite.

Key Point #2 – Onsite Cleaning
For equipment that must be cleaned on site, the Reside nt Engineer must be notified in advance. All waste from onsite cleaning operations must be fully contai ned and disposed of outside the highway right-ofway.

Key Point #3 – Wash Area Requirements
The vehicle wash area must be properly identified by sign (Photo 1) and located away from storm drain inlets, drainage facilities, and watercourses. It must be paved with concrete (Photo 2) or asphalt and have a berm to contain runoff and prevent run-on. It must be equipped with a sump for the collection and disposal of wash water.

Photo 1 Photo 2
Key Point #4 – Water Conservation
Use as little water as possible and use a positive s hut-off valve to conserve on water usage. 68 EXHIBIT A
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Vehicle and Equipment Cleaning NS-8
Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Workers clean personal vehicles on site. Personal vehicles and work trucks and/or equipment that regularly leave the site shall be cleaned offsite.

Wash water leaves the site. Contain wash water in a bermed area and dispose of water outside the right-of-way.

Washing occurs on a pervious surface.

Contain water in a concrete or paved bermed area. Place a sump in the wash area and transfer wash water to sanitary sewer system or temporary sediment trap. Never discharge wash water to storm drains or receiving waters.

Vehicle fluids are spilled onto the washrack.

Clean up spilled material and dispose of properly. Contain contaminated water and dispose of properly. Do not allow spilled material to flow to storm drain system.
69 EXHIBIT A
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Vehicle and Equipment Fueling NS-9
NS-9 VEHICLE AND EQUIPMENT FUELING
Potential fuel spills and leaks from vehicle/equipmen t fueling operations must be prevented from entering storm drain systems or receiving waters.

Applications
All construction sites
Key Points
Key Point #1 – Fuel Offsite
All vehicles and equipment that regularly enter and l eave the construction site should be fueled offsite.

Key Point #2 – Fueling Area Location
Designated fueling areas are selected by the contract or and approved by the Resident Engineer. The fueling area should be on level grade and must be at least 15 m (50 ft) downstream of storm drain facilities or receiving waters. The fueling area should be protected by a berm or dike to prevent storm water run-on and to prevent storm water from leaving the fueling area (Photo 1).

Photo 1
Key Point #3 – Spill Response
Absorbent spill clean-up materials and spill kits must be available in fueling areas and on fueling trucks.

Spills should be cleaned up immediately. Absorbent materials should be used on small spills. All used absorbent materials must be disposed of properly.

Key Point #4 – Leak Containment
Drip pans or absorbent pads must be placed under vehi cles/equipment if being fueled in areas other than a dedicated fueling area with an impermeable surface (Photo 2). 70 EXHIBIT A
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Vehicle and Equipment Fueling NS-9
Photo 2
Key Point #5 – Fueling Guidelines
Fueling operations are not to be left unattended. Fuel tanks are not to be topped off. Mobile fueling trucks must also follow BMP guidelines.

Key Point #6 – Fuel Nozzles
Fuel nozzles are to be equipped with automatic shut-off to control drips. Where required by Air Quality Management Districts, vapor recovery nozzles shall be used.

Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Vehicles and equipment leak fuel. Do not top off vehicle fuel tanks. Repair immediately or remove problem vehicles or equipment from the project site.

Fueling tanks are not stored in temporary
containment facilities. Place fuel tanks in bermed temporary containment facility.

Fuel spills on ground.

Use absorbent material to clean up spill and dispose of used clean-up materials properly. Never hose down or bury spills.

If fuel spills on soil, clean up contaminated soil and dispose of properly.
71 EXHIBIT A
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Vehicle and Equipment Maintenance NS-10
NS-10 VEHICLE AND EQUIPMENT MAINTENANCE
Petroleum products, lubricants, solvents, and other po llutants related to vehicle/equipment maintenance must be prevented from entering storm drain systems or receiving waters.

Applications
All construction sites
Key Points
Key Point #1 – Offsite Storage and Maintenance
All vehicles and equipment that regularly enter and leave the construction site should be maintained offsite.

Key Point #2 – Maintenance Area Design
Designated vehicle maintenance areas must be at least 15 m (50 ft) downstream of storm drain facilities or receiving waters. For long-term projects, a porta ble tent or cover over the maintenance area is recommended.

Key Point #3 – Maintenance Operations
For maintenance involving fluids, place drip pans or absorbent pads under the vehicle unless the work is being done in a dedicated maintenance area constructed over an impermeable surface.

Key Point #4 – Spill Prevention/Cleanup
All fluid and oil leaks must be cleaned up immediately. The maintenance area must be equipped with appropriate absorbent spill clean-up materials (Photo 1).

Photo 1
Key Point #5 – Waste Disposal
All used absorbents must be disposed of properly. Waste fluids must be placed in appropriate leak-free containers with secondary containment. All used ma intenance materials should be disposed of properly off the construction site. Used fluids, tires, batte ries, etc. are not to be dumped or buried on the construction site.
72 EXHIBIT A
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Vehicle and Equipment Maintenance NS-10
Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Used batteries are stored on the ground. Remove batteries from site or place them in a temporary containment facility.

Used oil, filters, and vehicle fluids are stored onsite. Place used materials in a temporary containment facility and schedule regular pickups to dispose of these materials.

Vehicles and equipment leak fluids onto the
ground.

Clean up spills on pavement with absorbent. Clean up
contaminated soil. Dispose of clean-up waste properly. Place drip pans or absorbent materials under parked vehicles and equipment. Repair equipment and vehicles immediately or remove from the project site.

Absorbent spill clean-up materials are not kept
onsite.

Instruct contractor to keep an ample supply of absorbent clean-up materials on site at all times during maintenance operations.

Run-on flows onto the maintenance area. Construct a berm, dike, or temporary diversion structure around maintenance facility.
73 EXHIBIT A
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Pile Driving Operations NS-11
NS-11 PILE DRIVING OPERATIONS
Proper control and use of equipment, materials, and waste products from pile driving operations will reduce the discharge of potential pollutants to the storm drain system or watercourse.

Applications
All construction sites near or adjacent to a wate rcourse or groundwater where permanent and temporary pile driving operations take place.

Key Points
Key Point #1 – Be Prepared
Use drip pans or absorbent pads at all times. However, the equipment should be as leak-free as possible.

Have spill kits and clean-up materials available at a ll pile driving locations. Implement other BMPs as applicable. Always comply with all applicable permits.

Key Point #2 – Equipment Use
Park equipment over plastic sheeting or equivalent. Plastic sheeting is not a substitute for drop pans or absorbent pads. Use less hazardous products, e.g. vegetable oil, when practicable.

Key Point #3 – Equipment Storage
Store pile driving equipment away from flowlines, dr ainage courses, and inlets. Protect hammers and other hydraulic attachments from run-on by placing them on plywood. Cover them with plastic when rain is forecast.

Key Point #4 – Inspection and Maintenance
Inspect entire pile driving areas and equipment (Photo 1) for leaks and spills on a daily basis. Inspect equipment routinely for damage and repair equipment as needed.

Photo 1
74 EXHIBIT A
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Pile Driving Operations NS-11
Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Used oil, filters, and fluids are stored onsite. Place used materials in a temporary containment facility and schedule regular pickups to dispose of these materials.

Equipment leaks fluids onto the ground.

Clean up spills on pavement with absorbent. Clean up
contaminated soil. Dispose of clean-up waste properly.

Place drip pans or absorbent materials under parked
equipment. Repair equipment immediately or remove from
the project site.

Absorbent spill clean-up materials are not kept
onsite.

Instruct contractor to keep an ample supply of absorbent clean-up materials on site at all times during pile driving operations.
75 EXHIBIT A
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Concrete Curing NS-12
NS-12 CONCRETE CURING
Following proper procedures in the use of cure, chemical or water, during construction of concrete structures will minimize pollution through run-off.

Applications
All construction sites where concrete stru ctures are subject to curing requirements.

Key Points
Key Point #1 – Use of Chemical Cure
Protect drain inlets prior to application of cure. Use proper storage and handling techniques at all times and have spill kits available at the location of curi ng. .Avoid over-spraying cure, allowing it to become airborne.

Key Point #2 – Use of Water Cure
Ensure cure water does not flow to inlets or waterc ourses but rather to collection areas for infiltration or other means of removal approved by the RE a nd in accordance with all applicable permits.

Key Point #3 – Inspection and Maintenance
Ensure that cure is stored (Photo 1), handled, and used properly. Ensure that the Contractor keeps cure containers leak-free and spray nozzles clean.

Photo 1
Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Cure containers are not in secondary containment. Place materials in a temporary containment facility and store in permanent secondary containment when no longer in use.

Chemical cure is becoming airborne. Ensure that the cure is applied close to the concrete surface to minimize cure becoming airborne.

Absorbent spill clean-up materials are not kept
onsite.

Instruct contractor to keep an ample supply of absorbent clean-up materials on site at all times.

Temporary diversion devices that collect cure water
needs maintenance.

Ensure the contractor is aware of the situation. If
maintenance is not done, inform the RE.
76 EXHIBIT A
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Material and Equipment Use on Water NS-13
NS-13 MATERIAL AND EQUIPMENT USE ON WATER
Following proper procedures in the use, storage, and disposal of materials and equipment on barges, boats, docks, temporary construction pads, or similar location will minimize or eliminate the discharge of potential pollutants to a watercourse.

Applications
All sites where materials and equipment are used on barges (Photo 1), boats, docks, and other platforms over or adjacent to a watercourse.

Key Points
Key Point #1 – Be Prepared
Use drip pans and absorbent materials under equipment and vehicles expected to be idle more than one hour. Ensure that an adequate supply of spill clean- up materials is available. Identify types of spill control measures to be employed, including the stor age of necessary clean-up materials and equipment.

Key Point #2 – Be Aware
Ensure NS-10 is implemented. If repairs cannot be made, remove the equipment from over the water.

Ensure compliance with all other pe rmits associated with the project.

Key Point #3 – Secure the Area
Provide watertight curbs or toe boards to contain sp ills and prevent materials, tools, and debris form leaving the barge, platform, dock, etc. Secure all materials to prevent discharge to the watercourse via wind.

Photo 1
Key Point #4 – Inspection and Maintenance
Ensure timely and proper removal of accumulated wast e. Inspect equipment for leaks and spills on a daily basis and ensure necessary repairs are done. Ensure proper procedures of storage and use of materials and equipment are being followed. Inspect and maintain all associated BMPs and perimeter controls to ensure continuous protection of the watercourse. 77 EXHIBIT A
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Material and Equipment Use on Water NS-13
Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

A discharge to the watercourse occurs.

Report the discharge to the RE immediately. Clean up the discharge as much as possible. Determine the cause and
secure the area.

A spill occurs without discharging into the
watercourse. Deploy spill clean up kits and supplies.

Vehicles and equipment parked over water bodies
leak fluids.

Place drip pans under all vehicl es and equipment that are placed on structures over water bodies that will be idle for more than one hour.
78 EXHIBIT A
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Concrete Finishing NS-14
NS-14 CONCRETE FINISHING
Following proper procedures in performing concrete finishing methods will minimize the impact of potential pollutants on runoff.

Applications
All sites where concrete finishing operations are performed.

Key Points
Key Point #1 – Containment
Ensure containment of all waste materials from high-pr essure water blasting, sandblasting, grinding, etc.

Without containment or water suppression of particl es, these operations can become problems (Photo 1).

Photo 1
Key Point #2 – Disposal
Refer to NS-2, “Dewatering” and the Dewatering Manual for options. Ensure disposal method is approved by the RE and is in compliance with applicable permits in advance of disposal.

Key Point #3 – Secure the Area
Protect all inlets that may be affected by any c oncrete finishing work. Direct any water, through nonerodible methods, to collection areas for infiltration or other disposal means.

Key Point #4 – Inspection and Maintenance
Inspect containment structures prior to use, during use, and prior to rainfall. If any repairs are required, ensure these are done in a timely manner and especially before a rain event. After use or at the end of the shift, ensure containment structures and general work area are clean and the wastes are disposed of properly.
79 EXHIBIT A
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Concrete Finishing NS-14
Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Concrete finishing waste materials are not
contained or cleaned up.

Ensure the Contractor knows he must contain all finishing wastes and remove them from the project in a timely
manner.

Inlets are not protected. Ensure all inlets that may be affected are protected during concrete finishing.

Containment structure is inadequate. Ensure the Contractor is aware of the situation and makes any necessary repairs or maintenance immediately.
80 EXHIBIT A
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Structure Demo/Removal Over or Adjacent to Water NS-15
NS-15 STRUCTURE DEMOLITION/REMOVAL OVER OR ADJACENT TO WATER Following proper procedures during structure demoliti on or removal operations will protect watercourses from debris and wastes associated with these operations.

Applications
All construction projects with full or partial struct ure demolition or removal, e.g., bridge widenings, concrete channel removal, etc.

Key Points
Key Point #1 – Containment
Use attachments on construction equipment to catch debr is or use covers or platforms to collect debris and prevent it from falling into the watercourse. Debris catching devices must be emptied regularly and the debris stored away from the watercourse and protected until removal.

Photo 1
Key Point #2 – Disposal
Dispose of accumulated debris in a timely manner and at an approved disposal site. For hazardous waste disposal, refer to WM-6.

Key Point #3 – Inspection and Maintenance
Inspect equipment and any debris catching devices on a daily basis. Ensure any stockpiles are protected and disposed of properly. Any discharge must be reported to the RE immediately. 81 EXHIBIT A
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Structure Demo/Removal Over or Adjacent to Water NS-15
Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

A discharge to the watercourse occurs.

Report the discharge to the RE immediately. Clean up the discharge as much as possible. Determine the cause and
secure the area.

A spill occurs without discharging into the
watercourse. Deploy spill clean up kits and supplies.

Vehicles and equipment parked over water bodies
leak fluids.

Place drip pans under all vehicl es and equipment that are placed on structures over water bodies that will be idle for more than one hour.

Debris falls into the watercourse. Remove as much as possible with the available means, e.g. floating booms.

Inlets are not protected. Ensure all inlets that may be affected are protected during concrete finishing.

Containment structure is inadequate.

Ensure the Contractor is aware of the situation and makes any necessary repairs, maintenance, or modification
immediately.
82 EXHIBIT A
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Temporary Batch Plants NS-16
NS-16 TEMPORARY BATCH PLANTS
Proper control and use of equipment, materials, a nd waste products from temporary batch plant facilities will reduce the potential of pollutant discharges to storm drain systems and/or watercourses, reduce air emissions, and mitigate noise impacts.

Applications
Construction projects where temporary batch plant facilities are used. Batch plants may be on or off site.

Key Points
Key Point #1 – Planning
A Notice of Intent (NOI) must be submitted to th e SWRCB for construction and operation of a temporary batch plant. Consideration for minimizing nuisance noise and impacts to air and water quality should be observed during construction and operation. Appropriate BMPs must be implemented within the boundaries of the batch plant in accordance with the approved SWPPP.

Key Point #2 – Layout and Design
Batch plants should be located at least 300 ft away from any recreational area, school, residence, or other structure not associated with the construction proj ect. AC or PCC berms should be constructed around plant equipment to facilitate proper containment and cleanup. Runoff should be directed to a collection area or baker tank.

Key Point #3 – Operational Procedures
Designate a concrete washout area in accordance with WM-8. All operations should be conducted so as to have no visible emissions including fabric or cartridge type filters for dry material transfers, dust-tight service hatches on silos and auxiliary bulk storage trailers, wet suppression systems at all transfer points, and covered conveyors and transporting vehicles. All plant roads shall be stabilized, watered, treated, or paved so as to control dust and tracking. All en trances and exits shall likewise be stabilized.

Key Point #4 – Materials Storage and Disposal
Refer to WM-1, “Material Delivery and Storage” as well as WM-2, “Material Use” for proper handling procedures and secondary containment requirements. All stockpiles within the batch plant boundaries shall be in accordance with WM-3, “Stockpile Manage ment.” Refer to WM-4, 5, 8, and 10 for further discussion of handling and disposal of wastes.

Key Point #5 – Inspection and Maintenance
Inspect batch plant equipment, components, and BMPs daily during construction and operation.

Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Cement transfer to silos produces excessive dust. Check fabric or filter at transfer point and repair if necessary. 83 EXHIBIT A
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Streambank Stabilization NS-17
NS-17 STREAMBANK STABILIZATION
Proper planning and procedures for work in and around streams and channels can reduce the potential for discharge of sediment and other pollutants and minimize the impacts of construction activities on watercourses and habitat.

Applications
Construction projects that disturb or occur within stream channels and associated riparian areas.

Key Points
Key Point #1 – Planning
Planning should consider scheduling, avoidance of in-stream construction, minimizing disturbance area and construction time, using pre-disturbed areas, sel ecting crossing location, and selecting equipment.

Key Point #2 – Associated BMP Selection for Streambanks Preservation of existing vegetation (SS-2) in a str eambank provides water quality protection, streambank stabilization, and riparian habitat. Hydraulic mu lch (SS-3), hydroseeding (SS-4), soil binders (SS-5), straw mulch (SS-6), or a combination may be used on disturbed streambanks to provide temporary soil stabilization. Be sure to review the limitations of each so that a selection of the most appropriate one for the given conditions may be made. Also consider possible use of other soil stabilization and sediment control BMPs provided the application is appr opriate and the limitations are not applicable.

Key Point #3 – In-stream Sediment Control
The primary goal while working in a stream is minimizing turbidity. There are three general ways to achieve this: construct a water diversion away from the work area, implement a water barrier around the work area, or employ practices that minimize sediment suspension.

Key Point #4 – Inspection and Maintenance
Inspect BMPs and equipment daily and ensure necessar y repairs for both are done in a timely manner. If a piece of equipment leaks, remove it from the stream immediately for repairs.

Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Equipment in stream leaks fluids. Remove it immediately for repairs.

Erosion occurs along the streambank. Use appropriate BMP to stabilize streambank or repair/replace current materials as necessary.
84 EXHIBIT A
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Material Delivery and Storage WM-1

WASTE MANAGEMENT AND MATERIALS POLLUTION CONTROL
WM-1 MATERIAL DELIVERY AND STORAGE
Materials associated with construction activities must be delivered and stored using practices that prevent these materials from polluting receiving waters. Typical materials include PCC components, petroleum products, pesticides, herbicides, fertilizers, detergents, plasters, acids, lime, glues, adhesives, paints, and solvents.

Applications
All construction sites with applicable material storage Key Points
Key Point #1 – Storage Areas
Store materials indoors in existing structures when available. Temporary storage sheds must meet building and fire code requirements and should be located away from vehicle traffic. Storage instructions should be posted (Photo 1), and employees should be trained in proper storage and delivery procedures.

Key Point #2 – Hazardous Materials
Do not store hazardous materials directly on the ground. Store liquid chemicals in drums and bags on pallets under cover and in secondary containment. Store materials in original containers with their original product labels (Photo 2).

Photo 1 Photo2
Key Point #3 – MSDS
The contractor must provide the Resident Engineer with the Material Safety Data Sheets (MSDS) for all materials stored on the site.

Key Point #4 – Liquid Materials and Petroleum Products
Do not store incompatible materials in the sam e temporary storage facility. Allow sufficient space between stored containers to allow for spill cleanup and emergency response access. 85 EXHIBIT A
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Material Delivery and Storage WM-1
Key Point #5 – Containment
Temporary containment facilities for storage must be of sufficient volume to contain precipitation from a 24-hour, 25-year storm event, plus the greater of 10% of the aggregate volume of all containers or 100% of the capacity of the largest tank within its bounda ry, whichever is greater. (Photo 3). Accumulated rainwater or spills should be removed from containment areas promptly.

Photo 3
Key Point #6 – Bagged/Boxed Materials
Store materials delivered in bags and boxes on pallets. Cover bagged/boxed materials on non-working days and prior to rain events to protect materials from wind and precipitation.

Key Point #7 – Spill Cleanup
Contain and clean up spills immediately in accordance with BMPs detailed in Spill Prevention and Control (WM-4).

Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Hazardous materials are not stored in
temporary containment devices.

Place hazardous materials in an appropriate temporary containment facility.

Hazardous substances are not labeled. Re-label items with an original label or remove substances from the site.

Hazardous chemicals, drums, or bagged
materials are stored directly on the ground.

Place material on a pallet and when possible, under cover and in temporary containment.

Temporary containment facilities have
standing water in them.

Pump out standing water into a containment device and dispose of properly. The water should be tested for possible pollutants and disposed of properly.

Materials are stored outside. Place materials on a raised platform and cover as needed to provide run-on and runoff control.

Incompatible materials such as chlorine and
ammonia are stored together.

Place incompatible materials in separate temporary storage facilities.

Temporary containment facilities are not
covered.

When practicable, cover containment facilities at all times. At a minimum, cover containment facilities on non-work ing days and prior to rain events.

There are no spill clean-up materials onsite.

Instruct contractor to purchase an ample supply of clean-up materials for materials being stored onsite and keep them close to the temporary storage areas.
86 EXHIBIT A
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Material Use WM-2
WM-2 MATERIAL USE
Materials associated with construction activities must be used in accordance with practices that prevent them from polluting receiving waters. Typical materials include AC, PCC, PCC compounds, petroleum products, pesticides, herbicides, fertilizers, detergents, plasters, acids, lime, glues, adhesives, paints, solvents, and curing compounds.

Applications
All construction sites with applicable material uses
Key Points
Key Point #1 – MSDS
The contractor must provide the Resident Engineer with the Material Safety Data Sheets (MSDS) for all materials used on the site.

Key Point #2 – Paint Materials
Mix paint indoors or in a containment area. Allow time for drying before rain events. Never clean brushes or rinse equipment so waste water enters street, gutte r, storm drain, or receiving water. Items used with water-based paint can be cleaned, discharging rinse wa ter to a sanitary sewer. When dry, empty latex paint cans, brushes, etc. can be disposed of with other construction debris. Filter used paint thinner/solvents and reuse. Paint thinners and solvents that cannot be recycled must be disposed of as hazardous waste.

Key Point #3 – Landscaping-Related Products
The contractor must complete a “Report of Ch emical Spray Form” when spraying herbicides and pesticides. Products must be applied by a licensed applicator. Do not over-apply fertilizers or pesticides and follow product usage recommendations. Apply in small amounts, allowing time for product to work in or dry before rain events.

Key Point #4 – Spill Cleanup
Maintain spill clean-up materials near areas that products will be used.

Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Improper disposal of waste water from washing
paint brushes occurs.

When practicable, wash paint brushes in a drain that is connected to a sanitary sewer system or into a concrete washout pit or temporary sediment trap.

Paint mixing occurs onsite. Mix paints indoors or in a containment area.

Disposal of latex paint occurs onsite.

Collect all excess paint. Paint cans, brushes, rags, absorbent materials, and rags, when thoroughly dry, may be disposed of with other construction debris.

Paint thinner or solvent is spilled during use.

Clean up spills on pavement with absorbent. Spills on soil should be cleaned up by removing contaminated soil and
disposing of properly.
87 EXHIBIT A
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Stockpile Management WM-3
WM-3 STOCKPILE MANAGEMENT
Construction stockpiles of materials such as soil, P CC, AC, PCC/AC rubble, aggregate base, aggregate sub-base, and asphalt based cold-mix have the potentia l to pollute receiving waters if not protected from contact with storm water.

Applications
All construction sites with applicable stockpiles
Key Points
Key Point #1 – General Guidelines
Stockpile protection is a year-round requirement. Insta ll temporary barriers around stockpile perimeters to prevent contact with storm water when required. Te mporary barriers can be berms, dikes, silt fences (Photo 1), straw bales, or sandbag barriers. All active stockpiles are to be protected by linear sediment barriers prior to rain events.

Key Point #2 – Soil Stockpiles
During the rainy season, cover inactive soil stockpiles (P hoto 2) or protect them with soil stabilization at all times (Photo 3). During the non-rainy season, cover in active soil stockpiles or protect them with linear barriers prior to rain events.

Photo 1 Photo 2
Key Point #3 – Paving Material Stockpiles
During the rainy season, cover inactive stockpiles of PCC, AC, AC/PCC rubble, and aggregate base and sub-base, and protect with a temporary perimeter ba rrier at all times. During the non-rainy season, cover inactive stockpiles or protect with a linear barrier prior to rain events.

Key Point #4 – Asphalt Based Cold-Mix Stockpiles
Place active and inactive cold-mix stockpiles on plastic and cover with plastic prior to rain events (Photo 4). The key is to prevent contact between rainfall and run-on with the stockpiles. 88 EXHIBIT A
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Stockpile Management WM-3
Photo 3 Photo 4
Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Soil stockpile erodes.

Cover stockpile with plastic sheeting or spray with a soil stabilizer. Protect with a temporary perimeter sediment barrier around the stockpile.

Stockpile is in flow line. Remove stockpile from drainage path or protect with a berm, dike, or temporary diversion device.

Storm water run-on impacts the stockpile.

Protect the stockpile by using temporary perimeter
sediment barriers such as berms, dikes, silt fencing, or sandbags.

Wind causes erosion and or blowing dust. Cover stockpile or spray with a soil stabilizer. Use a water application to suppress dust.

Cold-mix stockpile is on the bare ground. Remove stockpile and place on plastic or comparable material.

Cold-mix is stored in curb drainage way. Remove stockpile from flow line. 89 EXHIBIT A
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Spill Prevention and Control WM-4
WM-4 SPILL PREVENTION AND CONTROL
Spill prevention and prompt appropriate spill respon se reduces the potential for polluting receiving waters with spilled contaminants. Spills of concern in clude chemicals and hazardous wastes such as soil stabilizers/binders, dust palliatives, herbicides, growth inhibitors, fertilizers, de-icing products, fuels, lubricants, paints, and solvents.

Applications
All construction sites where chemicals or hazardous materials are stored or used Key Points
Key Point #1 – Spill Types
Be prepared for spills. Locate and clearly label sp ill kits and used absorbent containers (Photo 1).

Respond to all spills immediately upon discovery. The appropriate spill response is determined by the quantity and/or composition of spilled substance, as follows:
• A “minor spill” involves a small quantity of oil, gas, paint, etc. that can be controlled by the first responder upon discovery of the spill.
• A “semi-significant spill” can be controlled by the fi rst responder with the aid of other personnel and may require cessation of all other activity.
• A “significant/hazardous spill” is a spill that cannot be controlled by personnel in the immediate vicinity.

Photo 1
Key Point #2 – Minor Spill Response
• Contain the spill.
• Recover the spilled material.
• Clean the spill area. Use absorbent ma terials. Do not hose down the area. • Dispose of clean-up materials appropriately.
90 EXHIBIT A
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Spill Prevention and Control WM-4
Key Point #3 – Semi-Significant Spill Response
• On impermeable surfaces, surround the spill with abso rbent material to contain it. Clean spill using absorbent material.
• On dirt areas, construct an earthen dike to contain the spill. Dig up contaminated soil and dispose of properly.
• If spill occurs during rain, cover spill area to prevent contaminating storm runoff.

Key Point #4 – Significant/Hazardous Spill Response
• Contractor notifies the RE immediately.
• Contractor calls 911 and appropriate county officials. • Contractor notifies the Governor’s Office of Emergency Services Warning Center (805) 852-7550. • For spills meeting federal quantities, the contract or notifies the National Response Center (800) 424- 8802.
• All verbal notification must be followed up by written reports. • Contractor obtains services of spill contractor or a HazMat team immediately. Contractor staff is not to attempt cleanup until qualified assistance has arrived onsite.

Key Point #5 – Education
Train employees regarding the appropriate response for spills for the materials they use. Incorporate spill response procedures into regular safety meetings.

Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Material spills occur on a permeable surface. Contain spread of spill with an earthen dike. Dig up and properly dispose of contaminated soil.

Material spills occur on an impermeable surface. Use dry absorbent materials to encircle and contain the spill.

Place clean-up materials in a drum and dispose of properly.

The spill exceeds the cap acity of spill cleanup
materials on site.

Contain spill. Obtain enough spill clean-up materials to completely clean up the spill. Contact Caltrans Maintenance.

Store additional spill clean-up materials as necessary.

Spilled material encroaches onto travel way.

Contact Caltrans Maintenance. Use additional spill clean-up materials as necessary and replenish these materials in adequate quantity for future use.
91 EXHIBIT A
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Solid Waste Management WM-5
WM-5 SOLID WASTE MANAGEMENT
Solid construction wastes must be collected, stored, a nd disposed of using practices that minimize contact with storm water. Solid wastes include such items as used brick, mortar, timber, steel, vegetation/landscaping waste, empty material containers, and litter.

Applications
All construction sites
Key Points
Key Point #1 – Waste Storage Areas
Solid waste storage areas should be located in an area with little potential for flooding and at least 15 m (50 ft) from drainage facilities and receiving waters. Use berms, dikes, or temporary diversion structures to protect stockpiled waste materials from contacting storm water. During foul weather, waste should be stored in watertight dumpsters or securely c overed. Salvage or recycle waste as appropriate.

Key Point #2 – Litter Control
Provide adequate trash receptacles in the yard, field trailer areas, and where workers gather for breaks and meals (Photo 1). Do not place litter receptacles near drainage inlets or receiving waters. All litter within the construction site is to be collected weekly, regardless of the litter’s origin. Litter is to be removed from the site by trash hauling contractors.

Photo 1
Key Point #3 – Dumpsters
Provide an adequate number of watertight dumpsters to collect the anticipated volume of construction waste. Plan for additional dumpsters and dumpster pickups during demolition phases. Do not place dumpsters near drainage inlets or receiving waters. Full dumpsters are to be removed from the site and disposed of outside the highway right-of-way. Washi ng out dumpsters on the project site is prohibited.

Key Point #4 – Litter and Debris
Do not let litter interfere with the functioning of the storm drain system. Ensure that litter and debris are removed regularly from drainage grates and ditch lines (Photo 2). 92 EXHIBIT A
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Solid Waste Management WM-5
Photo 2
Key Point #5 – Hazardous Wastes
Separate potentially hazardous waste from non-hazardous w aste. Do not dispose of toxic liquid wastes in dumpsters designated for construction wastes. Dis pose of hazardous wastes in accordance with WM-6.

Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Runoff runs through waste stockpiles.

Locate stockpiles away from dr ainage courses or place a berm, dike, or temporary diversion structure around
stockpiles.

Lunch trash is left on the ground.

Place trash receptacles in yards, field trailers, or where workers gather for lunch and breaks. Instruct personnel on waste disposal procedures.

Trash containers leak. Install watertight liner, remove, or replace leaky containers.

The public dumps trash on site.

Block access to areas where dumping occurs. Keep trash
cleaned up to discourage dumping. Place sign that illegal dumping is prohibited.

Hazardous waste is intermixed with solid waste.

Segregate hazardous waste from solid waste. Instruct
employees and workers to identify and properly dispose of hazardous waste.
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Hazardous Waste Management WM-6
WM-6 HAZARDOUS WASTE MANAGEMENT
Hazardous wastes should be collected, stored, and dispo sed of using practices that prevent contact with storm water. The following types of wastes are considered hazardous: petroleum products, concrete curing compounds, palliatives, septic wastes, pain ts, stains, wood preservatives, asphalt products, pesticides, acids, solvents, and roofing tar. Ther e may be additional wastes on the project that are considered hazardous. It is also possible that non- hazardous waste could come into contact with these hazardous wastes, such that they become contaminated and are therefore considered hazardous waste.

Applications
All construction projects
Key Points
Key Point #1 – Hazardous Material Use
Use containment berms in fueling areas. Provide sec ondary containment in paint mixing areas (Photo 1) and paint clean-up areas. Place hazardous waste co llection containers at convenient locations.

Photo 1
Key Point #2 – Hazardous Waste Storage Areas
Ensure that adequate waste storage volume is provided and is located away from storm drains and receiving waters. Provide temporary containment su fficient to contain precipitation from a 24-hour, 25- year storm event, plus 10% of the aggregate volume of all containers or 100% of the capacity of the largest tank within its boundary, whichever is greater . Temporary containment should be impervious to spilled wastes for a minimum of 72 hours (Photo 2). Equip storage areas with appropriate spill clean-up materials. Allow sufficient space between storage c ontainers to allow for spill cleanup and emergency response access.

Key Point #3 – Hazardous Waste Containers
Store hazardous wastes in appropriate sealed containers that are clearly labeled with contents and starting date of accumulation. Do not mix different types of waste together in one container. Do not store incompatible wastes in the same temporary containment facility. If dry waste containers are not watertight, store containers on pallets. Prior to pred icted rain events, cover the containment area (Photo 3).
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Hazardous Waste Management WM-6
Photo 2 Photo 3
Key Point #4 – Disposal
Hazardous waste is to be transported from the site by a licensed hazardous waste transporter and disposed of at an authorized, licensed disposal or recycling facility within 90 days of being accumulated. Properly dispose of rain water removed from temporary contai nment that may have mixed with hazardous waste.

Key Point #5 – Education
Contractor and subcontractor employees should be e ducated regarding identification, storage, and disposal of hazardous wastes. Ongoing hazardous wast e training should be incorporated into regular safety meetings.

Key Point #6 – Inspection and Maintenance
Ensure that hazardous waste storage areas are inspected in conformance with contract provisions. Repair or replace perimeter controls, containment structures, covers, and liners as needed.

Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Rain water mixes with
hazardous materials. Collect rain water and then properly dispose of as hazardous waste.

Hazardous waste
containers are stored in the
open.

Place hazardous waste containers in temporar y containment and cover prior to rain events.

Hazardous waste
containers are not labeled.

Clearly label all hazardous waste containers with the waste being stored and the beginning date of accumulation.

Temporary containment
area is inadequate to
contain waste or hazardous
materials.

Temporary containment facilities should be constructed to contain precipitation from a 24-hour, 25-year storm event, plus 10% of the aggregate volume of all containers or 100% of the capacity of the largest tank within its boundary, whichever is greater.

Temporary containment
facilities are not covered.

When practicable, cover containment facilities at all times. At a minimum, cover containment facilities on non-working days and prior to rain events.

Dry wastes are stored on
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Contaminated Soil Management WM-7
WM-7 CONTAMINATED SOIL MANAGEMENT
Contaminated soil on construction sites should be managed to prevent any pollutants from entering storm drain systems or receiving waters. Typical soil contamination is due to spills, illicit discharges, underground storage tank leaks, or aerially deposited l ead (ADL). Contaminated soils tend to occur on projects in urban or industrial areas. Soil contaminants and locations are often identified in the project plans and specifications.

Applications
Areas of contamination as identified on project plans and specifications Suspected areas of contamination due to site hist ory, spills, leaks, soil discoloration/odor, abandoned tanks, pipes, or buried debris
Highway widening project where adjoining soils may contain ADL Key Points
Key Point #1 – Aerially Deposited Lead (ADL)
Soil from areas with ADL may be used as indicated in the contract special provisions providing that operations result in no visible dust. When excavati ng soils containing ADL, monitor air quality. Soils containing ADL may also be transported to a licensed landfill or other disposal site. At all times, prevent storm water, groundwater, etc. from mixing with and transporting contamination.

Key Point #2 – Identification and Coordination
If needed, staff from a Caltrans-approved certified lab shall test suspected soil. Upon confirmation of contamination, contractor shall work with appropria te local, state, and federal agencies to implement appropriate excavation, transportation, and disposal practices.

Key Point #3 – Stockpiling
Avoid stockpiling contaminated soils. If stockpiling is necessary, cover stockpile with plastic sheeting or tarps, install a berm around stockpile to prevent run- on, and locate the stockpile away from storm drains and receiving waters. Photo 1 shows contaminat ed soil stockpiled too close to an inlet.

Photo 1
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Contaminated Soil Management WM-7
Key Point #4 – Underground Storage Tank Removal
Obtain required approvals and permits from applicable local, state, and federal agencies prior to removal.

If tank contains liquid or sludge, ensure that it is t ested for hazardous substances prior to removal. Test underlying soils to determine if there is contamin ation. Prevent storm water, groundwater, etc. from mixing with and transporting contaminated substan ces from the storage tank. Ensure that tank and any liquid, sludge, or contaminated soils are transported and disposed of properly.

Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Contaminated soil must be stockpiled onsite.

Cover the stockpile with plastic sheeting or a tarp.

Construct a berm around the stockpile to prevent runoff from leaving the area. Do not place stockpiles near storm drains or watercourses.

Water becomes mixed with contaminated soils. Collect the water and treat or transport to an appropriate disposal site.
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Concrete Waste Management WM-8
WM-8 CONCRETE WASTE MANAGEMENT
Concrete waste materials must be properly managed to minimize or eliminate contact with storm water.

Applications
On construction sites where new concrete is pl aced or demolition of concrete structures occurs Where concrete slurries are generated such as sawing, coring, grinding, and grooving At mortar mixing stations
Key Points
Key Point #1 – Concrete Slurry Waste
Place temporary berms or sandbags around coring and saw -cutting locations to contain slurry. Vacuum slurry waste or collect it in a temporary lined pit and allow it to dry. Dispose of concrete waste in compliance with Solid Waste Management (WM-5).

Key Point #2 – Temporary Concrete Washout
Wash out concrete trucks in designated areas only (Photo 1). Locate washout facilities a minimum of 15 m (50 ft) from storm drains or receiving waters. Keep the washout areas away from areas of construction traffic. A sign shall be installed at each location in accordance with Standard Specification Section 56-2, “Roadside Signs.” The facility shall have a pit or berm to provide sufficient volume to contain all concrete waste resulting from washout. Allow concrete waste to dry and then dispose of on a regular basis in conformance with Standard Specifica tions, Section 15-3.02, “Removal Methods.” Photo 1
Key Point #3 – Above Grade Washout Facilities
Above grade facilities (Photo 2) shall be construc ted as shown in the details. A minimum length and width of 3 m (10 ft) is recommended, but the area should have sufficient volume to contain the anticipated waste. The lining material shall be a minimum of 10-mil polyethylene sheeting, free of holes or other defects.
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Concrete Waste Management WM-8
Photo 2
Key Point #4 – Below Grade Washout Facilities
Below grade facilities shall be constructed as shown in the details. A minimum length and width of 3 m (10 ft) is recommended, but the area should have suffi cient volume to contain the anticipated waste from operation. The lining material shall be a minimum of 10-mil polyethylene sheeting, free of holes or other defects. Commercial type lath and flagging shall be used.

Key Point #5 – Inspection and Maintenance
Washouts should be maintained to provide a minimum 100 mm (4 in) freeboard for above ground facilities and 300 mm (1 ft) freeboard for below gr ade facilities. Maintenance includes removal and disposal of hardened concrete as previously describ ed. Existing facilities must be cleaned or additional facilities constructed when the w ashout is 75% full (Photo 3).

Photo 3
Key Point #6 – Washout Removal
Materials used to construct the facility become the property of the contractor and shall be removed and disposed of outside the highway right-of-way in c onformance with Standard Specifications, Section 7-

1.13. Holes and depressions shall be backfilled and repa ired in conformance with Standard Specifications, Section 15-1.02, “Preservation of Property.”
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Concrete Waste Management WM-8
Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Concrete washout overflows. Discontinue using washout and construct new facility to contain anticipated washout operations.

Concrete washout discharges into storm drain.

Notify the Construction Storm Water Coordinator of
potential non-compliance. Clean up as much of the waste as possible. Place washout at least 15 m (50 ft) from drainage facilities or receiving waters. Ensure the washout is
designed to contain the volume of anticipated wastes.

Protect storm drain while conducting washout with inlet cover, sandbags or other BMP.

Drivers wash out trucks at locations of their
choosing.

Place sign at washouts and instruct drivers of the washout locations.
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Sanitary/Septic Waste Management WM-9
WM-9 SANITARY/SEPTIC WASTE MANAGEMENT
This BMP includes procedures to prevent the introduc tion of wastes from construction site toilet facilities to storm drains or receiving waters.

Applications
All construction sites that use temporary or portable sanitary/septic waste systems Key Points
Key Point #1 – Installation
Temporary sanitary facilities should not be located near drainage facilities (Photo 1) or receiving waters, nor should they be located in areas that will collect water (Photo 2). If the site is deemed to be a high wind area by the RE, the facilities shall be secured to prevent overturning.

Photo 1 Photo 2
Key Point #2 – Sanitary Sewer Discharge
Discharges direct to the sanitary sewer should be in compliance with local health agency and sewer district requirements. Ensure that the temporary f acility is properly connected to the sanitary sewer to prevent illicit discharges.

Key Point #3 – On-Site Disposal
Waste water shall not be discharged or buried within the highway right-of-way (Photo 3). Ensure that any on-site disposal systems comply with local health agency requirements. 101

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Sanitary/Septic Waste Management WM-9
Photo 3
Key Point #4 – Inspection and Maintenance
The contractor’s Water Pollution Control Manager (W PCM) shall monitor sanitary/septic waste storage and disposal procedures weekly. Ensure that the san itary/septic facilities are maintained in good working order and wastes are transported offsite by a licensed service.

Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Sanitary facilities tip over.

Place sanitary facility on level surface and out of drainage paths or traffic areas. Use Spill Prevention and Control (WM-4).

Sanitary facility leaks. Repair or replace sanitary facility.

Sanitary facility is cleaned onsite near storm drain.

Place sanitary facility away from drainage inlets or
receiving waters. Contain water in a temporary trapping device.
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Liquid Waste Management WM-10
WM-10 LIQUID WASTE MANAGEMENT
This BMP includes procedures to prevent pollutant s related to non-hazardous liquid wastes from entering storm drains or receiving waters. Liquid wastes include drilling slurries, drilling fluids, wastewater that is free from grease and oil, dredgings, and other non-storm water liquid discharges not covered by separate permits. This BMP does not apply to the following:
• Dewatering operations (See NS-2)
• Solid wastes (See WM-5)
• Hazardous wastes (See WM-6)
• Concrete slurries (See WM-8)
• Liquid wastes covered by specific laws or permits
• Non-storm water discharges permitted by any Caltrans NPDES permit unless Caltrans determines that the discharge contains pollutants
Applications
All construction sites where liquid wastes are generated Key Points
Key Point #1 – Capture
Capture all liquid wastes that have the potential to impact water entering the storm drain system. Use temporary dikes or berms to direct surface flow of liquid wastes to a containment structure or device. If liquid waste contains sediment, capture and treat the fl ow to remove sediment or capture in a containment structure to allow sediment to settle.

Key Point #2 – Containment
Contain liquid wastes in a controlled area that is structurally sound, leak-free, and provides sufficient storage for the anticipated volume. Appropriate stru ctures include holding pits, sediment basins, roll-off bins, and portable tanks. Locate the containment structure such that accidental releases do not discharge to storm drains or receiving waters or threaten health or safety.

Key Point #3 – Disposal
Some liquid wastes may require testing and certification that they are non-hazardous before an appropriate disposal method is selected. Liquid waste may need to be treated to remove sediment or other pollutants prior to disposal. Typical liquid waste dis posal requires Dewatering (NS-2) with disposal of resulting solids per Solid Waste Management (WM- 5) or Standard Specification Section 7-1.13, “Disposal of Material Outside the Highway Right-of-Way.” Key Point #4 – Inspection and Maintenance
Frequently inspect liquid waste containment areas and capturing devices for damage. Repair as needed.

Preventive Measures and Troubleshooting Guide
Field Condition: Common solutions are:

Liquid waste is sediment- laden. Construct a temporary Sediment Trap (SC-3) and allow sediment to settle. Properly dispose of liquid waste.

Liquid waste discharge is uncontrolled. Capture flows by using temporary dikes or berms to intercept flows and direct them to a containment device.
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Notes
PART IV: NOTES

DISTRICT CONSTRUCTION STORM WATER COORDINATORS
1 Kirk Carrington (530) 582-9129
2 Ted Schultz (530) 225-4640
3 Kirk Carrington (530) 582-9129
4 Frank Gorham (510) 286-5185
5 Pete Riegelhuth (805) 549-3661
6 Raafat Shehata (559) 488-4284
Sheri West (661) 395-2795
7 James Burt (213) 897-1960
8 Walt Griffith (909) 232-6496
9 Richard Epler (209) 786-2932
10 Richard Epler (209) 786-2932
11 Michael Kolbenschlag (858) 467-4080
12 Mark Doroudian (949) 724-2834

CALTRANS HEADQUARTERS ENVIRONMENTAL WEBSITE
www.dot.ca.gov/hq/env/stormwater/index.htm

COMMENTS AND QUESTIONS
Please fax comments, questions, or concerns regard ing this manual or other BMP news to 714-567-2780. 104

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APPENDIX VIII

CALIFORNIA REGIONAL WATER QUALITY

CONTROL BOARD GUIDELINES

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UST lab requirements for oxygenates (9/06) 1

STATE OF CALIFORNIA
California Regional Water Quality Control Board
Los Angeles Region
(Underground Storage Tank Program)
General Laboratory Testing Requirements for Petroleum Hydrocarbon Impacted Sites
The purpose of this document is to supplement the Regional Board’s Laboratory Report Form (6/00) in order to update obsolete testing requirements and set forth the new requirements for fuel oxygenates and natural attenuation testing. Each analytical method used must be certified by the California Environmental Accreditation Laboratory Program (ELAP).

1. General Laboratory QA/QC Requirements
Conform to the Regional Board’s Laboratory Report Form (6/00) in general, except for items specified below.

2. Compounds to be Tested
Total petroleum hydrocarbons in gasoline range (TPHg) (C4 – C12); Total petroleum hydrocarbons in diesel range (TPHd) (C13 – C22); benzene, toluene, ethylbenzene, xylenes (BTEX); methyl tertiary butyl ether (MTBE); di-isopropyl ether (DIPE); ethyl tertiary butyl ether (ETBE); tertiary amyl methyl ether (TAME); tertiary butyl alcohol (TBA).

If the gasoline tanks historically or currently contain methanol or ethanol, these compounds are also to be tested.

3. Analytical Test Methods and Detection Limits
Conform to Table 1 below. Report any concentration detected between the method detection limit (MDL) and estimated quantitation limit (EQL) (or reporting limit (RL)) in a numerical value with a “J” flag indicator. All “Non-Detect” (ND) shall be reported in the format with “< (numerical MDL).” Integrate all fuel oxygenate additive concentrations into total petroleum hydrocarbons (TPH) and report it as TPH. EPA Method 8021B may be used to substitute EPA Method 8260B at the sites where all fuel oxygenates have not been identified by EPA Method 8260B in soil and/or groundwater.

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General Laboratory Testing Requirements for Petroleum Hydrocarbon Impacted Sites
UST lab requirements for oxygenates (9/06) 2
Table 1: Analytical Requirements
Analyte Analytical Method
Required MDL
(Method
Detection Limit)
Soil (mg/kg)
Required MDL
(Method Detection
Limit)
Water (mg/L)
BTEX EPA Method 8260B(8021B) 1 0.5
MTBE EPA Method 8260B 2 1
DIPE EPA Method 8260B 2 1
ETBE EPA Method 8260B 2 1
TAME EPA Method 8260B 2 1
TBA EPA Method 8260B 20 10
TPHg Cal-LUFT GC/FID or GC/MS 100-200 50-100
TPHd Cal-LUFT GC/FID 1000 500
Methanol Cal-LUFT GC/FID 1000 500
Ethanol Cal-LUFT GC/FID(EPA8260B) 500 250

4. Use of EPA Method 5035 for Soil Samples
Apply EPA Method 5035A specified in the USEPA SW-846, (7/2002) for soil sample preparation and preservation in order to minimize volatile organic losses. Use the sample collection devices, or equivalent, specified in the method (e.g., the Encoreä sampler). If the Encoreä sampler is used, analyze sample within 48 hours from the collection.

Analyze sample within 14 days for soil samples stored under frozen conditions.

5. Natural Attenuation Parameters
Natural attenuation processes include dispersion, dilution, sorption, volatilization, biodegradation, and chemical or biological transformation. A carefully controlled monitoring program for the natural attenuation can be used to confirm site-specific mass reduction and achieve remedial objectives. In order to test parameters to confirm the occurrence of natural attenuation, site characterization must be complete first.

5.1 Primary Natural Attenuation Criteria
Meet the following conditions prior to testing for the secondary natural attenuation parameters:
a) Groundwater contaminant plume must be fully defined. b) Groundwater monitoring program on a quarterly basis must be completed for at least two years including data of MTBE and other oxygenates.
c) Groundwater concentration has consistently decreased or been stable.

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General Laboratory Testing Requirements for Petroleum Hydrocarbon Impacted Sites
UST lab requirements for oxygenates (9/06) 3
d) Determination of site-specific hydraulic conductivity must be conducted: Refer the ASTM D4044-91 for the slug test procedures. Other field methods (e.g., pumping test) are also acceptable to determine hydraulic conductivity. e) Characterization of MTBE and other oxygenates plume vertical extent must be completed with discrete multi-depth groundwater sampling at all groundwater vulnerable areas designated by the Board.

5.2 Secondary Natural Attenuation Parameters
Analyze the secondary natural attenuation parameters only after the primary natural attenuation criteria are met. Analyze the secondary natural attenuation parameters at all groundwater monitoring wells inside and outside of the plume. Conform to Table 2 below for parameters and testing methods.

Table 2:Analytical Requirements for Secondary Natural Attenuation Parameters Parameter Test Method Required MDL
pH EPA Method 150.2 or Field instrument n/a
Dissolved oxygen (DO) EPA Method 360.1 or Field instrument n/a Redox potential (ORP) Field instrument n/a
Sulfate (SO4) EPA Method 300 5 mg/L
Nitrate (NO3) EPA Method 300 0.1 mg/L
Ferrous iron (Fe2+) EPA Method 200 0.1 mg/L
Methane (CH4) EPA Method 8015(M) 5 mg/L

6. Electronic Submittal of Data Reporting
All analytical results shall be uploaded in an electronic format to the State GeoTracker Database.

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APPENDIX IX

CHEVRON ENROACHMENT

REQUIREMENTS

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California State Fire Marshal
Information Bulletin 03-001
Issued: June 20, 2003
(Revised September 25, 2019)
ENCROACHMENTS INTO or ON PIPELINE EASEMENTS
The purpose of this informational bulletin is to delineate the position of the State Fire Marshal regarding encroachments onto the pipeline easements.

Section 51014.6 of the California Government Code states, “(a) Effective January 1, 1987, no person, other than the pipeline operator, shall do any of the following with respect to any pipeline easement:
(1) Build, erect, or create a structure or improvement within the pipeline easement or permit the building, erection, or creation thereof. (2) Build, erect, or create a structure, fence, wall, or obstruction adjacent to any pipeline easement which would prevent complete and unimpaired surface access to the easement, or permit the building, erection, or creation thereof. (b) No shrubbery or shielding shall be installed on the pipeline easement which would impair aerial observation of the pipeline easement.

This subdivision does not prevent the revegetation of any landscape disturbed within a pipeline easement as a result of construction the pipeline and does not prevent the holder of the underlying fee interest or the holder’s tenant from planting and harvesting seasonal agricultural crops on a pipeline easement. (c) This section does not prohibit a pipeline operator from performing any necessary activities within a pipeline easement, including, but not limited to, the construction, replacement, relocation, repair, or operation of the pipeline.

It is the position of the State Fire Marshal that nothing shall encroach into or upon the pipeline easement, which would impede the pipeline operator from complete and unobstructed surface access along the pipeline right of way. Nor shall there be any obstructions, which would shield the pipeline right of way from observation. In the interest of public safety and the protection of the environment, it is imperative that the pipeline operator visually assesses the conditions along the easement to ensure the integrity of the pipeline.

It is the responsibility of the pipeline operator to ensure they have unimpeded surface access and to be able to physically observe all portions of their pipeline rights of way. In cases where this is not possible, the pipeline operator shall inform the State Fire Marshal. The State Fire Marshal shall in conjunction with the pipeline operator resolve the issue.

Questions regarding the issue of pipeline encroachment can be addressed to:

CAL FIRE-Office of the State Fire Marshal
Pipeline Safety Division
3780 Kilroy Airport Way #500
Long Beach, CA 90806 Phone:(562) 497-0350

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APPENDIX X

PHASING PLAN NEAR SHERIFF STATION

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PHASED WORK AROUND LA COUNTY SHERIFF STATION
The following is an illustration to showcase the phasing plan for the water main replacement work as well as the paving work in the area near the Los Angeles County Sheriff Department (LASD) - Lomita Station. • The current circulation at the Sheriff Station is represented below:

Current Situation

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PHASED WORK AROUND LA COUNTY SHERIFF STATION
• The proposed phased work around the Sheriff Station shall be as follows:

BLOCKED *
FROM 9 AM TO 3 PM
Construction
Phase 1

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PHASED WORK AROUND LA COUNTY SHERIFF STATION
Construction
Phase 2
NOTES:
- During the time when the entrance/exit is blocked from 9 AM to 3PM, the Contractor shall halt work at any time to allow access for LASD vehicles at short notice. - The above phasing plan is tailored to the water main replacement portion of the project as well as the paving portion of the project.

BLOCKED *
FROM 9 AM TO 3 PM

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APPENDIX XI

CARB FLEET CERTIFICATION

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65265.00001\42648333.1

FLEET COMPLIANCE CERTIFICATION
Contractor hereby acknowledges that they have reviewed the California Air Resources Board’s policies, rules and regulations and are familiar with the requirements of Title 13, California Code of Regulations, Division 3, Chapter 9, effective on January 1, 2024 (the “Regulation”).

Contractor hereby certifies, subject to penalty for perjury, that the option checked below relating to the Contractor’s fleet, and/or that of their subcontractor(s) (“Fleet”) is true and correct:
 The Fleet is subject to the requirements of the Regulation, and the appropriate Certificate(s) of Reported Compliance have been attached hereto.
 The Fleet is exempt from the Regulation under section 2449.1(f)(2), and a signed description of the subject vehicles, and reasoning for exemption has been attached hereto.  Contractor and/or their subcontractor is unable to procure R99 or R100 renewable diesel fuel as defined in the Regulation pursuant to section 2449.1(f)(3). Contractor shall keep detailed records describing the normal refueling methods, their attempts to procure renewable diesel fuel and proof that shows they were not able to procure renewable diesel (i.e. third party correspondence or vendor bids).
 The Fleet is exempt from the requirements of the Regulation pursuant to section 2449(i)(4) because this Project has been deemed an Emergency, as defined under section 2449(c)(18).

Contractor shall only operate the exempted vehicles in the emergency situation and records of the exempted vehicles must be maintained, pursuant to section 2449(i)(4).  The Fleet does not fall under the Regulation or are otherwise exempted and a detailed reasoning is attached hereto.

Name of Contractor:________________________________________________ Signature: __________________________________________________ Name: __________________________________________________ Title: __________________________________________________ Date: __________________________________________________

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APPENDIX XII
NPDES 2022 CONSTRUCTION

STORMWATER GENERAL PERMIT

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MS4 DISCHARGES WITHIN THE

LOS ANGELES REGION
PERMIT NO. CAS004004
ATTACHMENT F – FACT SHEET F-1
NDPES PERMIT NO CAS004004

CONTENTS
I. Permit Information.............................................................................................................F-6 A. Dischargers................................................................................................................F-7 B. Discharges.................................................................................................................F-7 C. Permit Scope .............................................................................................................F-7 D. Rationale for Issuance of a Regional Phase I MS4 Permit........................................F-8 II. Facility Description ..........................................................................................................F-11 A. Description of Receiving Waters and Watershed Management Areas ....................F-11 B. Geographic Coverage and Watershed Management Areas ....................................F-11 C. Description of the Permittees’ MS4s........................................................................F-22 D. Description of Flood Control District Permittees ......................................................F-27 E. Nature of MS4 Discharges as a Source of Pollutants to Receiving Waters and Need for Regulation ..........................................................................................................F-28 F. History of the Previous Permits ...............................................................................F-48 G. Summary of Requirements in Previous Permits ......................................................F-51 H. Permit Applications ..................................................................................................F-60 III. Applicable Federal and State Laws, Regulations, Plans, and Policies ...........................F-61 A. Municipal Separate Storm Sewer System Requirements ........................................F-61 B. Water Quality Control Plans ....................................................................................F-62 C. National Toxics Rule (NTR) and California Toxics Rule (CTR) ...............................F-64 D. Endangered Species Acts .......................................................................................F-65 E. NPDES Electronic Reporting Rule (e-Rule).............................................................F-65 F. Monitoring and Reporting ........................................................................................F-65 G. Standard Provisions.................................................................................................F-66 H. Antidegradation Policy .............................................................................................F-66 I. Anti-Backsliding Requirements..............................................................................F-102 J. Human Right to Water Law....................................................................................F-122 K. Advancing Measures to Mitigate and Adapt to Climate Change ...........................F-122 L. California Environmental Quality Act (CEQA)........................................................F-124 M. Advancing Racial Equity ........................................................................................F-124 N. Other Plans, Policies, and Regulations .................................................................F-124 IV. Rationale for Discharge Prohibitions.............................................................................F-124 A. Non-Stormwater Discharges..................................................................................F-124 B. Trash......................................................................................................................F-139 V. Rationale for Effluent Limitations and Discharge Specifications ...................................F-144 A. Technology-Based Effluent Limitations .................................................................F-144 B. Water Quality-Based Effluent Limitations (WQBELs) ............................................F-147 VI. Rationale for Total Maximum Daily Load Provisions.....................................................F-153 A. Clean Water Act Section 303(d) List and Relationship to TMDLs .........................F-153 B. TMDLs and Their Implementation Through NPDES Permits.................................F-153 C. TMDL Provisions ...................................................................................................F-155 D. Manner of TMDL Incorporation..............................................................................F-168 E. WQBELs for Trash.................................................................................................F-178 F. U.S. EPA Established TMDLs ...............................................................................F-181 G. Compliance Schedules for Achieving TMDL Requirements ..................................F-188 H. Considerations Regarding Extensions of TMDL Deadlines ...................................F-201 VII. Rationale for Receiving Water Limitations ....................................................................F-202

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MS4 DISCHARGES WITHIN THE ORDER NO. R4-2021-0105
LOS ANGELES REGION NPDES NO. CAS004004
ATTACHMENT F – FACT SHEET F-2
VIII. Rationale for Standard Provisions.................................................................................F-205 A. Standard Provisions...............................................................................................F-205 B. Legal Authority.......................................................................................................F-205 C. Fiscal Resources ...................................................................................................F-206 D. Responsibilities of the Permittees..........................................................................F-206 E. Public Review and Los Angeles Water Board Review ..........................................F-207 F. Reopener and Modification Provisions ..................................................................F-207 G. Other Provisions ....................................................................................................F-207 IX. Rationale for Stormwater Management Programs and MCMs .....................................F-207 A. General Requirements...........................................................................................F-208 B. Progressive Enforcement ......................................................................................F-210 C. Modifications/Revisions .........................................................................................F-211 D. Public Information and Participation Program .......................................................F-211 E. Industrial/Commercial Facilities Program ..............................................................F-216 F. Planning and Land Development Program............................................................F-221 G. Construction Program............................................................................................F-224 H. Public Agency Activities Program ..........................................................................F-227 I. Illicit Discharge Detection and Elimination Program ..............................................F-233 X. Rationale for Watershed Management Programs.........................................................F-238 A. Previous Permit Requirements ..............................................................................F-238 B. General Rationale for All Watershed Management Programs...............................F-239 C. Schedule for Development or Revision of the Watershed Management Program F-242 D. Participation in Watershed Management Programs ..............................................F-243 E. Program Development...........................................................................................F-244 F. Watershed Management Program Implementation ...............................................F-246 G. Integrated Watershed Monitoring and Assessment...............................................F-247 H. Adaptive Management Process.............................................................................F-247 XI. Rationale for Compliance Determination Provisions.....................................................F-248 A. General Compliance Provisions ............................................................................F-249 B. WQBELs and Receiving Water Limitations for Pollutants Other Than Trash ........F-249 C. WQBELs and Receiving Water Limitations for Trash ............................................F-252 D. Commingled Discharges........................................................................................F-252 E. Time Schedule Orders...........................................................................................F-253 XII. Rationale for Monitoring and Reporting Requirements .................................................F-253 A. Legal Authorities Supporting Monitoring and Reporting ........................................F-254 B. General Monitoring Provisions...............................................................................F-258 C. Monitoring Programs .............................................................................................F-259 D. Monitoring Locations for Ventura County MS4 Permittees ....................................F-260 E. Receiving Water Monitoring Requirements ...........................................................F-261 F. Stormwater Outfall-Based Monitoring Requirements ............................................F-292 G. Non-Stormwater Outfall-Based Screening and Monitoring Requirements ............F-293 H. TMDL Monitoring ...................................................................................................F-300 I. Outfall-Based Database.........................................................................................F-301 J. Aquatic Toxicity Monitoring Methods .....................................................................F-301 K. Regional Studies....................................................................................................F-304 L. Special Studies ......................................................................................................F-304 M. Reporting Requirement Objectives........................................................................F-304 N. Standard Monitoring and Reporting Provisions .....................................................F-305 O. Reporting Requirements........................................................................................F-305 P. TMDL Reporting ....................................................................................................F-307 XIII. California Water Code Section 13241...........................................................................F-307

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A. Past, Present, and Probable Future Beneficial Uses of Water..............................F-311 B. Environmental Characteristics of the Hydrographic Unit Under Consideration, Including the Quality of Water Available Thereto...................................................F-312 C. Water Quality Conditions that Could Reasonably be Achieved Through the Coordinated Control of All Factors Which Affect Water Quality in the Area ..........F-313 D. Economic Considerations ......................................................................................F-319 E. The Need for Developing Housing Within the Region ...........................................F-374 F. The Need to Develop and Use Recycled Water ....................................................F-375 XIV. State Mandates .............................................................................................................F-380 A. Renewal of the Permits Is Not a New Program Or Higher Level of Service ..........F-380 B. The Permit Requirements Fall Under Several Exceptions to Mandates Rules......F-381 XV. Public Participation........................................................................................................F-387 A. Permittee and Stakeholder Participation in Permit Issuance Process ...................F-387 B. Notification to Permittees and Interested Parties...................................................F-404 C. Written Comments .................................................................................................F-404 D. Public Hearing .......................................................................................................F-405 E. Reconsideration of Waste Discharge Requirements .............................................F-405 F. Information and Copying........................................................................................F-405 G. Register of Interested Persons ..............................................................................F-405 H. Additional Information ............................................................................................F-406 TABLES
Table F-1. Facility Information ...................................................................................................F-6 Table F-2. Select Permittees’ MS4-Related Infrastructure ......................................................F-23 Table F-3. Los Angeles County Impervious Area ....................................................................F-24 Table F-4. Summary of Major Constituents Exceeding TMDL Targets and/or Basin Plan Water Quality Objectives at Mass Emission Stations During Wet Weather Conditions (2009- 2017)........................................................................................................................F-33 Table F-5. Summary of Major Constituents Exceeding TMDL Targets and/or Basin Plan Water Quality Objectives at Mass Emission Stations During Dry Weather Conditions (2009- 2017)........................................................................................................................F-34 Table F-6. Summary of Wet Weather Bacteria Monitoring at Receiving Water Stations.........F-35 Table F-7. Summary of Wet Weather Bacteria Monitoring at Outfall Stations .........................F-36 Table F-8. Summary of Dry Weather Bacteria Monitoring at Receiving Water Stations..........F-36 Table F-9. Summary of Dry Weather Bacteria Monitoring at Outfall Stations..........................F-38 Table F-10. Summary of Wet Weather Metals Receiving Water Monitoring Exceeding Criteria by Watershed (Exceedances / Samples) .....................................................................F-40 Table F-11. Summary of Wet Weather Metals Outfall Monitoring Exceeding Criteria by Watershed (Exceedances / Samples) ....................................................................F-41 Table F-12. Summary of Dry Weather Metals Receiving Water Monitoring Exceeding Criteria by Watershed (Exceedances / Samples) ....................................................................F-43 Table F-13. Summary of Dry Weather Metals Outfall Monitoring Exceeding Criteria by Watershed (Exceedances / Samples) ....................................................................F-44 Table F-14. Summary of Nutrients Receiving Water Monitoring Exceeding Criteria by Watershed (Exceedances / Samples)........................................................................................F-45 Table F-15. Summary of Nutrients Outfall Monitoring Exceeding Criteria by Watershed (Exceedances / Samples)........................................................................................F-45 Table F-16. Summary of Salts Monitoring at Receiving Water Stations ..................................F-46 Table F-17. Summary of Salts Monitoring at Outfall Stations ..................................................F-46

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Table F-18. Summary of Toxic Pollutants Receiving Water Monitoring Exceeding Criteria by Watershed (Exceedances / Samples) .....................................................................F-47 Table F-19. Multi-benefit projects funded through Proposition 1 To Date ...............................F-81 Table F-20. Measure W Funded Projects (2020-2021) ...........................................................F-86 Table F-21. Changes to Effluent Limitations in Previous MS4 Permits .................................F-102 Table F-22. General NPDES Permits, WDRs and Conditional Waivers Applicable to NonStormwater Discharges .........................................................................................F-131 Table F-23. Selected Compliance Option in Response to California Water Code Section 13383 Orders....................................................................................................................F-141 Table F-24. Incorporated TMDLs and Programs of Implementation......................................F-157 Table F-25. Status of TMDLs in the Regional MS4 Permit and Previous MS4 Permits.........F-164 Table F-26. TMDL Final Implementation Deadlines ..............................................................F-191 Table F-27. Rationale for Recommended Reporting Levels (RLs) in the Regional MS4 Permit .F266 Table F-28. Estimated Costs of Implementing TMDLs Through the Order by Watershed (millions, 2019 dollars)...........................................................................................F-325 Table F-29. Permittees’ Projected Cost Estimates for EWMP Full Implementation (millions of dollars, 2019$). ......................................................................................................F-327 Table F-30. Permittees’ Projected Cost Estimates for WMP Full Implementation (millions of dollars, 2019$). ......................................................................................................F-328 Table F-31. Permittees’ Projected Cost Estimates for WMP/EWMP Full Implementation, by Permittee (millions, 2019$)....................................................................................F-329 Table F-32. Ventura County Permittees’ Projected Capital Cost Estimates for Full Implementation through 2040, by Permittee (millions, 2019$)...............................F-333 Table F-33. Ventura County Permittees’ Projected Annual O&M Cost Estimates for Capital Projects (millions, 2019$). .....................................................................................F-334 Table F-34. Ventura County Permittees’ Projected Total Cost Estimates for Capital Projects (millions, 2019$). ...................................................................................................F-335 Table F-35. Ventura County WMP Development Costs (millions, 2019$). ............................F-336 Table F-36. Estimated Annual Costs Incurred by Ventura County MS4 Permittees for Stormwater Programs (2019$) ..............................................................................F-337 Table F-37. Estimated Annual Costs Incurred by Los Angeles County Permittees for Implementation of Stormwater Programs (2019$).................................................F-338 Table F-38. Total 20-Year MS4 Costs Estimated from Method 1 (millions, 2019$)...............F-342 Table F-39. Total 20-Year MS4 Costs Estimated from Method 2 (millions, 2019$)...............F-342 Table F-40. Estimated Annual Safe, Clean Water Program Municipal Program Funds, by Permittee ...............................................................................................................F-352 Table F-41. Estimated Annual Safe, Clean Water Program Regional Program Funds by Watershed Area.....................................................................................................F-353 Table F-42. Fiscal Year 2018/2019 Benefit Assessment Program Revenue for NPDES Compliance............................................................................................................F-356 Table F-43. Other Existing Municipal Stormwater Fees in the Los Angeles Region..............F-357 Table F-44. Funds Allocated to Stormwater Management in Los Angeles County Up To 2012..F358 Table F-45. Potential Future State and Federal Grant Sources ............................................F-359 Table F-46. Potential Future State and Federal Loan Sources .............................................F-361

FIGURES
Figure F-1. Non-Stormwater Outfall-Based Screening and Monitoring Program General Process ...................................................................................................................................... F-294

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Figure F-2. Map of Watershed Areas, Watershed Management Program Areas, and Enhanced Watershed Management Program Areas...................................................................... F-354

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ATTACHMENT F – FACT SHEET
As described in Part II of the Order, the Los Angeles Water Board incorporates this Fact Sheet as findings of the Los Angeles Water Board supporting the issuance of the Order. This Fact Sheet sets forth the principal facts and the significant factual, legal, methodological, and policy and technical rationale that serve as the basis for the requirements of the Order.

I. PERMIT INFORMATION
The following table summarizes administrative information related to the facility and the Dischargers.

Table F-1. Facility Information
WDID No.1 Various (see Table 2 and Table 3 of the Order) Dischargers
The Los Angeles County Flood Control District (LACFCD), the County of Los Angeles, the 85 incorporated cities within the coastal watersheds of Los Angeles County, the Ventura County Watershed Protection District (VCWPD), the County of Ventura, and the 10 incorporated cities within Ventura County (see Table 2 and Table 3 of the Order)2
Name of Facility Municipal Separate Storm Sewer Systems (MS4s) 3 within the coastal
watersheds of Los Angeles and Ventura counties
Facility Contacts,
Titles, Addresses, and
Phone Numbers
Available through the Stormwater Multiple Application and Report Tracking System (SMARTS)
4 at
https://smarts.waterboards.ca.gov/smarts/faces/SwSmartsLogin.xhtml Mailing Addresses Refer to SMARTS
Billing Addresses Refer to SMARTS
Type of Facility Large Municipal Separate Storm Sewer System (MS4) Major or Minor Facility Major
Discharge Points Locations throughout the Los Angeles Region Discharge Description Stormwater and Non-Stormwater Discharges Receiving Waters Various (see Part II.A of this Fact Sheet) 1 WDID No. stands for “Waste Discharge Identification” Number, which is a unique identifier given to a specific facility and regulatory measure (e.g., NPDES permit). In the case of the Order, each Discharger has a unique WDID number associated with its coverage under the Order. 2 Note that the cities of Palmdale and Lancaster, though in Los Angeles County, are not within the coastal watersheds of Los Angeles County and, therefore, are not under the jurisdiction of the Los Angeles Water Board. These two cities are under the jurisdiction of the Lahontan Water Board. 3 See Attachment A of the Order for definitions of terms, acronyms, and abbreviations used in the Order, including this Fact Sheet and all other attachments.
4 SMARTS provides a platform where dischargers, regulators, and the public can enter, manage, and view stormwater data including permit applications and compliance and monitoring data associated with NPDES permits for stormwater discharges issued by the State of California. SMARTS is compliant with U.S. EPA’s Cross-Media Electronic Reporting Rule, which sets requirements for electronic reporting of NPDES permit-related submittals.

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Receiving Water Type
Inland surface waters, estuarine waters, and marine waters, including but not limited to, lakes, rivers, estuaries, lagoons, harbors, bays, beaches, and the Pacific Ocean
A. Dischargers
The 99 municipalities listed in Table 2 and Table 3 of the Order are the owners and/or operators5 of Municipal Separate Storm Sewer Systems within the Los Angeles Region (hereinafter Facility or MS4). For the purposes of the Order, the entities listed in Table 2 and Table 3 of the Order are hereinafter referred to separately as “Permittees” and jointly as the “Dischargers.” References to “discharger” or “permittee” or “co-permittee” or “municipality” in applicable federal and state laws, regulations, plans, or policy are held to be equivalent to references to the Dischargers or Permittees herein.

References to “Los Angeles County MS4 Permittees” or “Los Angeles County Permittees” refer to LACFCD, the County of Los Angeles, and the 85 incorporated cities within Los Angeles County, excluding Lancaster and Palmdale which are not within the Los Angeles Water Board’s jurisdiction. References to “Ventura County MS4 Permittees” or “Ventura County Permittees” refers to VCWPD, the County of Ventura, and the 10 incorporated cities within Ventura County. Furthermore, reference to “Los Angeles Region” is defined per California Water Code section 13200(d) as follows: “Los Angeles region, which comprises all basins draining into the Pacific Ocean between the southeasterly boundary, located in the westerly part of Ventura County, of the watershed of Rincon Creek and a line which coincides with the southeasterly boundary of Los Angeles County from the ocean to San Antonio Peak and follows thence the divide between San Gabriel River and Lytle Creek drainages to the divide between Sheep Creek and San Gabriel River drainages.”
B. Discharges
Information about the Facility’s stormwater and non-stormwater discharges to waters of the United States is summarized in Table F-1 above. Permittees were previously regulated by (1) Order No. R4-2010-0108 and National Pollutant Discharge Elimination System (NPDES) Permit No. CAS004002, effective on July 8, 2010, (2) Order No. R4- 2012-0175 and NPDES No. CAS004001, effective on December 28, 2012, and (3) Order No. R4-2014-0024 and NPDES No. CAS004003, effective on March 28, 2014.

Attachment A of the Order lists definitions, abbreviations, and acronyms of terms used in the Order and all other attachments. Attachment B of the Order provides a map depicting each major Watershed Management Area (WMA), its subwatersheds, and the major receiving waters therein to which the Facility discharges. Attachment C of the Order depicts the major MS4-related infrastructure within the Los Angeles Region and monitoring locations for Ventura County Permittees.

C. Permit Scope
The Order regulates discharges of stormwater and non-stormwater from the Permittees’ MS4s. Section 122.26(b)(8) of title 40 of the Code of Federal Regulations (CFR)6 defines an MS4 as “a conveyance or system of conveyances (including roads with drainage systems, municipal streets, catch basins, curbs, gutters, ditches, manmade 5 Owner or operator means the owner or operator of any facility or activity subject to regulation under the NPDES program (40 CFR § 122.2).
6 All further statutory references are to title 40 of the Code of Federal Regulations unless otherwise indicated.

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channels, or storm drains): (i) [o]wned or operated by a State, city, town, borough, county, parish, district, association, or other public body (created by or pursuant to State law) having jurisdiction over disposal of sewage, industrial wastes, storm water, or other wastes, including special districts under State law such as a sewer district, flood control district or drainage district, or similar entity, or an Indian tribe or an authorized Indian tribal organization, or a designated and approved management agency under section 208 of the CWA that discharges to waters of the United States; (ii) [d]esigned or used for collecting or conveying storm water; (iii) [w]hich is not a combined sewer; and (iv) [w]hich is not part of a Publicly Owned Treatment Works (POTW) as defined at 40 CFR 122.2.”
Stormwater discharges consist of those discharges that originate from precipitation events. Federal regulations define “storm water” as “storm water runoff, snow melt runoff, and surface runoff and drainage.” (40 CFR § 122.26(b)(13)). While “surface runoff and drainage” is not defined in federal law, U.S. EPA’s preamble to its final stormwater regulations demonstrates that the term is related to precipitation events such as rain and/or snowmelt. (55 Fed. Reg. 47990, 47995-96 (Nov. 16, 1990)).

Non-stormwater discharges consist of all discharges through an MS4 that do not originate from precipitation events. Non-stormwater discharges through an MS4 are prohibited unless authorized under a separate NPDES permit; authorized by U.S. EPA pursuant to Sections 104(a) or 104(b) of CERCLA; composed of natural flows; the result of emergency firefighting activities; or conditionally exempted in the Order.

A permit issued to more than one Permittee for MS4 discharges may contain separate stormwater management programs for particular Permittees or groups of Permittees. (40 CFR § 122.26(d)(2)(iv)). Given LACFCD’s and VCWPD’s limited land use authorities, they are not subject to the Industrial/Commercial Facilities Program and the Planning and Land Development Program. However, as owners and operators of a MS4, LACFCD and VCWPD remain subject to the Public Information and Participation Program, Illicit Discharge Detection and Elimination Program, Public Agency Activities Program, and Construction Program. LACFCD and VCWPD are also subject to all other requirements of the Order, including but not limited to the discharge prohibitions, receiving water limitation provisions, TMDL provisions, monitoring and reporting provisions, and standard provisions.

D. Rationale for Issuance of a Regional Phase I MS4 Permit The Los Angeles Water Board retains the discretion as the permitting authority to determine whether to issue permits for discharges from MS4s on a system-wide or jurisdiction-wide basis. Clean Water Act section 402(p)(3)(B)(i) and implementing regulations at 40 CFR section 122.26, subdivisions (a)(1)(v), (a)(3)(ii), and (a)(3)(iv) allow the permitting authority to issue permits for MS4 discharges on a system-wide or jurisdiction-wide basis taking into consideration a variety of factors. Such factors include the location of the discharge with respect to waters of the United States, the size of the discharge, the quantity and nature of the pollutants discharged to waters of the United States, and other relevant factors. Federal regulations at 40 CFR section 122.26(a)(3)(ii) identify a variety of possible permitting structures, including one system-wide permit covering all MS4 discharges or distinct permits for appropriate categories of MS4 discharges including, but not limited to, all discharges owned or operated by the same municipality, located within the same jurisdiction, all discharges within a system that discharge to the same watershed, discharges within a MS4 that are similar in nature, or

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for individual discharges from MS4s. Consistent with CWA 402(p)(3)(B)(i), the Los Angeles Water Board is issuing the Order for its entire Los Angeles Region.

Additionally, the Los Angeles Water Board is issuing the Order to implement the State Water Board’s guiding principles for MS4 permit development by all regional water boards, which is provided in Order WQ 2015-0075.7 Specifically, the State Water Board declared:
“Phase I MS4 permits should (1) continue to require compliance with water quality standards in accordance with our Order WQ 99-05; (2) allow compliance with TMDL requirements to constitute compliance with receiving water limitations; (3) provide for a compliance alternative that allows permittees to achieve compliance with receiving water limitations over a period of time as described above; (4) encourage watershedbased approaches, address multiple contaminants, and incorporate TMDL requirements; (5) encourage the use of green infrastructure and the adoption of low impact development principles; (6) encourage the use of multi-benefit regional projects that capture, infiltrate, and reuse storm water; and (7) require rigor, accountability, and transparency in identification and prioritization of issues in the watershed, in proposal and implementation of control measures, in monitoring of water quality, and in adaptive management of the program.”
The application of these principles on a region-wide basis results in improved consistency and uniformity, where warranted, in Phase I MS4 permit requirements, while providing Permittees the flexibility to tailor their implementation through watershed management programs in consideration of socio-economic, land use, and geographic characteristics.

Two of the three Phase I MS4 permits issued by the Los Angeles Water Board, including Los Angeles County and the City of Long Beach, already incorporate these principles.

With regard to Ventura County MS4 Permittees, the previous Order, No. R4-2010-0108, was structured as a single permit whereby all 12 Permittees were assigned uniform requirements, with additional requirements for the Principal Permittee. With the issuance of the Los Angeles County MS4 Permit (Order No. R4-2012-0175) as amended by State Water Board Order WQ 2015-0075, the Los Angeles Water Board created a new permitting framework based on Watershed Management Areas to address MS4 discharges and water quality protection in the region. This framework 7 On April 21, 2021, the Los Angeles County Superior Court issued a final judgment in the case of Natural Resources Defense Council, Inc. and Los Angeles Waterkeeper v. State Water Resources Control Board and California Regional Water Quality Control Board, Los Angeles Region (Super. Ct. Los Angeles County, No. BS156962 (NRDC)). At issue was plaintiffs’ challenge to the adequacy of the Water Boards’ antidegradation analysis in the 2012 Los Angeles County MS4 Order. The trial court ruled that the Water Boards’ antidegradation analysis for any high quality waters was not supported by adequate findings. In furtherance of the judgment, the court will issue a writ ordering the State Water Board to set aside Order WQ 2015-0075. As of June 1, 2021, the court has not issued the writ and the State Water Board has taken no action to set aside Order WQ 2015-0075. As such, Order WQ 2015-0075 remains in effect and relevant to the analysis of many of the matters discussed herein. Even if Order WQ 2015-0075 is ultimately set aside, the trial court’s ruling was based solely on the antidegradation analysis for high quality waters and did not call into question the propriety of the State Water Board’s other holdings on the 2012 Los Angeles County MS4 Permit. Because these holdings have not been disturbed by the NRDC case, and because these holdings address matters relevant to the Regional MS4 Order, this Fact Sheet continues to cite and discuss Order WQ 2015-0075, as appropriate, for matters other than antidegradation concerning high quality waters.

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intended to provide a comprehensive and integrated strategy toward water resource protection, enhancement, and restoration within a hydrologically defined drainage basin or watershed while considering watershed specific characteristics in order to develop and implement a cost-effective program to achieve compliance. The Ventura County Permittees’ reapplication package supported the inclusion of the Watershed Management Program as an optional alternative compliance pathway in Ventura County. Additionally, the reapplication package assumed that the future permit would follow the structure of the Los Angeles County MS4 Permit in Order No. R4-2012-0175 and therefore, the Permittees framed their proposals for changes to the permit accordingly. As a result, the Los Angeles Water Board finds that the framework and principal elements of a MS4 permit need not differ between counties and/or Permittees in the Los Angeles Region. A Regional Phase I MS4 Permit, which incorporates a watershed-based approach, provides regional consistency, while allowing Permittees the opportunity to customize their stormwater management programs considering unique watershed characteristics.

The Los Angeles Water Board also considered the nature of most Permittees’ MS4s, which comprise a large interconnected system particularly in Los Angeles County where the discharges from these entities frequently commingle in the MS4 prior to discharge to receiving waters. Additionally, the City of Long Beach, which was previously regulated under its own permit, is geographically located at the base of 4 out of 10 of the watersheds within Los Angeles County and therefore has frequent commingling of its MS4 discharges with MS4 discharges of upstream Permittees in these watersheds.

The Los Angeles Water Board also considered the location of discharges and the nature of the receiving waters (see 40 CFR 122.26(b)(4)(iii) and (b)(7)(iii)). For example, while the MS4s in Los Angeles and Ventura County do not interconnect, they do discharge to some shared receiving waters (e.g., Malibu Creek, Santa Monica Bay, Santa Clara River). The City of Thousand Oaks (within Ventura County) and the City of Agoura Hills (within Los Angeles County) both discharge to Malibu Creek. Likewise, the cities of Ventura (within Ventura County) and Santa Clarita (within Los Angeles County) both discharge to Santa Clara River. The same is true within Ventura County where for example, the City of Ojai and the City of Ventura, both discharge to receiving waters in the Ventura River Watershed. Having one permit for MS4 discharges to the same receiving waters across Los Angeles and Ventura Counties allows to the Board to address water quality in a consistent manner.

Further necessitating a watershed framework is the requirement to implement 45 largely watershed-based TMDLs in the Order. Most Permittees have already established jurisdictional groups on a watershed or subwatershed basis for TMDL implementation. (See Attachment J of the Order for a matrix of these TMDLs and Permittees by WMA.) Some of the TMDLs apply to both Los Angeles County and Ventura County Permittees for the reason discussed above. These TMDLs also address multiple watersheds and the jurisdictional areas of multiple Permittees. Having separate permits makes implementation of the TMDLs more cumbersome.

Based on an evaluation of these factors, the Los Angeles Water Board determined that, because of the complexity and networking of the MS4 within the Los Angeles Region, that one system-wide permit is appropriate. In order to provide individual Permittees with specific requirements, the Order regulates the MS4 discharges of all 99 Permittees with some sections devoted to universal requirements for all Permittees. Some sections are devoted to distinct requirements for Los Angeles County Permittees and Ventura County Permittees and other sections devoted to requirements specific to each WMA,

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including TMDL implementation provisions. This structure is supported by section 402(p) of the Clean Water Act and 40 CFR sections 122.26, subdivisions (a)(1)(v), (a)(3)(ii), and (a)(3)(iv). A single permit will ensure consistency and equitability in regulatory requirements within the Los Angeles Region, while watershed-based requirements within the single permit will provide flexibility to tailor permit provisions to address distinct watershed characteristics and water quality issues. Additionally, an internal watershed-based structure comports with the Los Angeles Water Board’s Watershed Management Initiative and its watershed-based TMDL requirements.

Watershed-based requirements will help promote watershed-wide solutions to address water quality problems, which in many cases are the most efficient and cost-effective means to address stormwater and urban runoff pollution. Further, watershed-based requirements may encourage collaboration among permittees to implement regional integrated water resources approaches such as stormwater capture and re-use to achieve multiple benefits.

II. FACILITY DESCRIPTION
A. Description of Receiving Waters and Watershed Management Areas The area under the jurisdiction of the Los Angeles Water Board (Los Angeles Region) is 4,447 square miles in size. It contains 120 miles of coastline, 18,839 acres of lakes, and 1,704 miles of rivers and streams. Major Watershed Management Areas in the Los Angeles Region are shown on Figure B-1 of Attachment B of the Order and described below.

B. Geographic Coverage and Watershed Management Areas
The municipal stormwater and non-stormwater discharges from the MS4 enter receiving waters in the major Watershed Management Areas of the Ventura River Watershed; Miscellaneous Ventura County Coastal Watersheds; Santa Clara River Watershed; Calleguas Creek Watershed; Santa Monica Bay Watershed, including Malibu Creek Subwatershed, Ballona Creek Subwatershed, and Marina del Rey Subwatershed; Dominguez Channel and Greater Los Angeles and Long Beach Harbors Watershed, including Machado Lake Subwatershed; Los Angeles River Watershed; San Gabriel River Watershed; and Los Cerritos Channel and Alamitos Bay Watershed. The receiving waters within these WMAs include those identified in Tables 2-1, 2-1a, 2-3, 2- 3a, 2-4, 2-4a, and Appendix 1 Table 1, Table A2-1, Table A2-3 and Table A2-4 of the Water Quality Control Plan – Los Angeles Region (Basin Plan for the Coastal Watersheds of Los Angeles and Ventura Counties), and other unidentified tributaries to these surface waters.

The Order defines WMAs consistent with the delineations used by the Los Angeles Water Board. Permittees included in each of the major WMAs are listed in Attachment J of the Order. Maps depicting each WMA, its subwatersheds, and the major receiving waters therein are included in Attachment B of the Order.

Ventura River Watershed Management Area. The Ventura River and its tributaries drain a coastal watershed in western Ventura County. The watershed covers a fanshaped area of 235 square miles (150,400 acres), which is located within the western Transverse Ranges (the only major east-west mountain ranges in the continental U.S.) (Attachment B Figure B-2). From the upper slopes of the Transverse Ranges, the surface water system in the Ventura River watershed generally flows in a southerly direction to an estuary, located at the mouth of the Ventura River. Groundwater basins are highly interconnected with the surface water system and are recharged or depleted

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according to surface flow conditions. The surface waters that drain the watershed have very steep gradients, ranging from 40 feet per mile at the mouth to 150 feet per mile at the headwaters. Precipitation in the watershed varies widely and mostly occurs as rainfall during a few storms between November and March. Summer and fall months are typically dry. Although snow occurs at higher elevations, melting snowpack does not sustain significant runoff in warmer months. The unpredictable weather pattern, coupled with the steep gradients throughout most of the watershed, result in high flow velocities with most runoff reaching the ocean.

Land use in the watershed is predominantly open space with a mix of residential, agriculture, commercial and industrial uses along the mainstem of the river. The MS4s of the incorporated cities of Ojai and Ventura along with unincorporated areas of Ventura County discharge to the Ventura River system. Residents and agricultural interests in this watershed are entirely dependent on local surface water and groundwater and there is no connection to the State Water Project to deliver imported water.

Migratory steelhead trout ascend upstream in the Ventura River and into San Antonio Creek and may utilize areas above the Robles Diversion Dam via a fish passageway. A limited resident population of rainbow trout occurs above Robles Diversion Dam and in San Antonio Creek and the lower Ventura River. Multiple interested agencies, including Ventura County and other entities, have recognized the potential for the restoration and enhancement of steelhead populations in the Ventura River through the removal of Matilija Dam, which is in the upper watershed and blocks access to a large area of prime spawning habitat.

Wetlands are found at the Ventura River estuary as well as along the river and bordering lakes. The wetland at the mouth of the Ventura River is considered a significant biological resource by Ventura County due to its ability to provide habitat for thousands of biota that include endangered, rare, or threatened species. The mainstem of the river as well as San Antonio Creek are also listed as significant biological resources due to their use by steelhead trout. “Critical” condor habitat exists in three areas in Ventura County, including Matilija Creek.

Water quality in the upper reaches is good but quality in the lower reaches is influenced by a combination of municipal wastewater discharges, agricultural activities, livestock, MS4 discharges, and oil industry discharges among other sources of pollutants.

Excessive algae occurs at many locations and most water quality problems involve eutrophication. Total Maximum Daily Loads (TMDLs) have been established (as required by the federal Clean Water Act) to address water quality impairments due to trash, nutrients, eutrophic conditions and algae in the watershed.

Stakeholders in the watershed have formed several long-range water planning groups and have developed Integrated Regional Water Management (IRWM) Plans under Propositions 50 and 84. These Plans address the future water needs of each IRWM Region in terms of reliability of the water supply, improvement to water quality (including implementing TMDLs), increases in habitat and open space (additionally serving as areas for recharge of stormwater), and replacement of water-related infrastructure as needed. The stakeholders also propose projects to help implement the Plan’s goals; applicants may pursue funding through a variety of sources including grant funding available through bond programs. Ventura County Permittees within this watershed also participated in the development of a Storm Water Resource Plan pursuant to Water Code section 10563 et seq. in order to be eligible to apply for state funding for stormwater and dry weather runoff projects to improve water quality.

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Miscellaneous Ventura County Coastal Watershed Management Area. The Miscellaneous Ventura County Coastal WMA is composed of four separate coastal drainage areas located between the Los Angeles Water Board’s boundary with the Central Coast Water Board and the Ventura River, Santa Clara River, Calleguas Creek, and Santa Monica Bay WMAs (Attachment B Figure B-3). The drainage areas are typified by beaches, small coastal streams, coastal lakes, and harbors such as Ventura Harbor, Channel Islands Harbor, and Port Hueneme. The WMA encompasses an area that historically consisted of extensive coastal wetlands that were connected to the Pacific Ocean. Many unique habitats, including coastal wetlands and lagoons, such as McGrath Lake and Ormond Beach Wetlands, and the nearby coastal dunes remain in the WMA. They are identified as significant biological resources by Ventura County.

These areas provide habitats for many fish, birds, invertebrates, sea lions, and other marine and estuarine species
Land use in this WMA trends heavily to either open space or urban uses. The MS4s of the incorporated cities of Port Hueneme, Oxnard, and Ventura along with unincorporated areas of Ventura County discharge to these miscellaneous Ventura County Coastal Watersheds. Some of these waterbodies receive runoff from urban areas through sizable drains and pollutants associated with MS4 discharges will be found. The water quality problems found in the harbors in the WMA generally involve elevated bacteria, metals, and legacy pesticides. While residents and commercial/agricultural interests in this WMA utilize some local groundwater, they are highly dependent on imported water.

Channel Islands Harbor: Channels Islands Harbor is located south of the Santa Clara River and is in the immediate vicinity of considerable residential development and some agricultural land. Kiddie Beach and Hobie Beach, near the mouth of the harbor, are on the 2014/2016 Clean Water Act section 303(d) list due to impairment by indicator bacteria.

Port Hueneme Harbor: Port Hueneme Harbor is a medium-sized deep-water harbor located in Ventura County, north of Mugu Lagoon. The construction of most of the harbor was completed in 1975. A U.S. Navy Construction Battalion historically operated part of it. The rest of the harbor serves as a commercial port operated by the Oxnard Harbor District. Two endangered bird species may use the harbor, the California Brown Pelican, and the California Least Tern. The harbor is on the 2014/2016 Clean Water Act section 303(d) list for DDT and PCBs in fish/shellfish tissue. The DDT and PCB impairments in fish/shellfish tissue are being addressed through an action other than a TMDL (i.e., dredging).

Ventura Marina: Ventura Marina is a small craft harbor located between the mouths of the Ventura and Santa Clara Rivers. It is home to numerous small boats and two boatyards. The "Ventura Keys" area of the marina is a residential area situated along three canals. The marina is surrounded by agricultural land and a large unlined ditch drains into the Keys area. The marina and Ventura Keys area are on the 2014/2016 Clean Water Act section 303(d) list for indicator bacteria. In 2018, the Los Angeles Water Board re-evaluated the 303(d) listing for Ventura Keys and concluded that the waterbody should remain on the 303(d) list. The area around the jetties is listed as impaired for DDT and PCBs. The nearby Arundell Barranca is an open drain carrying mostly agricultural, commercial, and residential runoff, which flows into the marina.

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McGrath Lake: McGrath Lake is a small brackish waterbody located just south of the Santa Clara River. The lake is located partially on State Parks land and partially on privately-owned oilfields in current production. A number of agricultural ditches drain into the lake. The MS4 does not discharge into McGrath Lake. A state beach is located off the coastal side of the lake. The habitat around the lake is quite unique and it is utilized by a large number of overwintering migratory birds. The lake is on the 2014/2016 Clean Water Act section 303(d) list for several legacy pesticides.

Open Coastline: A major feature of the coastline north of Mugu Lagoon is Ormond Beach and Ormond Beach Wetlands. The ocean immediately off the coast was part of the Bight ’03, Bight ’98, and the 1994 Southern California Bight Regional Monitoring Program. The Ormond Beach Wetlands has been extensively characterized as part of a wetlands restoration planning process being led by the Coastal Conservancy. The Ormond Beach Task Force was formed in 1993 and meets as needed to address issues and projects that may affect the beach and wetlands. Major ongoing activities include work by U.S. EPA to characterize and clean up the Halaco Superfund site adjacent to Ormond Beach Wetlands and wetlands restoration planning being undertaken by the State Coastal Conservancy.

Additionally, the open coastline has numerous beaches. Several of these were historically listed on the 303(d) list as impaired due to bacteria. The Los Angeles Water Board re-evaluated these listings in 2019 and, based on the data analysis, recommended removing Ormond Beach, Peninsula Beach, Point Mugu Beach, Port Hueneme Beach Park, Rincon Parkway Beach, San Buenaventura Beach and Surfer’s Point at Seaside (also known as Seaside Park Beach) from the 303(d) list.

The Los Angeles Water Board recommended keeping Rincon Beach on the 303(d) list due to an ongoing bacteria impairment.

TMDLs have been developed for many of the impairments in the Miscellaneous Ventura County Coastal Watersheds. TMDLs in effect include those for bacteria at Kiddie Beach and Hobie Beach, bacteria at McGrath Beach, and PCBs, pesticides, and sediment toxicity at McGrath Lake.

Santa Clara River Watershed Management Area. The Santa Clara River and its tributaries drain a watershed area of 1,620 square miles (1,036,800 acres) (Attachment B Figure B-4). At approximately 100 miles (161 kilometers) in length, the Santa Clara River is the largest river system in southern California that remains in a relatively natural state. The river originates on the northern slope of the San Gabriel Mountains in Los Angeles County, traverses Ventura County, and flows into the Pacific Ocean between the cities of Ventura and Oxnard. Santa Clara River Reaches 1, 2, 3, 4A, 4B and major tributaries Santa Paula, Sespe and Piru Creeks are in Ventura County. Santa Clara River Reach 5 lies between Ventura County and Los Angeles County. Santa Clara River Reaches 6, 7, 8 and major tributaries Castaic, San Francisquito, and Bouquet Canyon Creeks are in Los Angeles County. About 40% of the watershed, the Upper Santa Clara River, is in Los Angeles County and about 60% of the watershed, the Lower Santa Clara River, is in Ventura County.

Land use in the watershed is predominately open space, most of which is National Forest or condor sanctuary. Residential, agriculture, and some industrial land uses occur along the mainstem. Portions of the MS4s of the incorporated cities of Santa Clarita, Fillmore, Santa Paula, Ventura and Oxnard and unincorporated areas of both counties discharge to the Santa Clara River system.

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Significant biological resources described in Ventura County’s General Plan include the extensive patches of high-quality riparian habitat that are present along the length of the river and its tributaries. Also considered significant are areas such as the wetlands found at the Santa Clara River estuary, along the river, and bordering lakes. One of the largest of Santa Clara River's tributaries, Sespe Creek, contains most of the Santa Clara River's remnant run of the steelhead trout. Piru and Santa Paula Creeks, two other tributaries of the Santa Clara River, also support good habitat for steelhead, although both contain barriers to migration. Additionally, the Santa Clara River has populations of unarmored three-spined stickleback (endangered), Santa Ana sucker, arroyo toad, and California least Bell’s vireo. San Francisquito Canyon, Placerita Canyon, Soledad Canyon, Castaic, and Elizabeth Canyon Creeks are smaller tributaries that all provide valuable habitat. The Santa Clara River also serves as an important wildlife corridor. A lagoon exists at the mouth of the river and supports a large variety of wildlife.

Various reaches of the Santa Clara River are on the 2014/2016 Clean Water Act section 303(d) list of impaired water bodies for pesticides, metals, indicator bacteria, salts, and trash, among other pollutants. The elevated bacterial indicator densities are causing impairment of the REC-1 and REC-2 designated beneficial uses for the Santa Clara River Estuary and Reaches 3, 5, 6, and 7. The Estuary is also listed for toxaphene and residual amounts of other legacy pesticides (ChemA) in fish tissue. The excessive levels of chloride are impairing the AGR and GWR designated beneficial uses of Santa Clara River Reaches 3, 4A, 4B, 5 and 6. The trash in Lake Elizabeth is causing impairments to the WARM, WILD, RARE, REC-1 and REC-2 designated beneficial uses. TMDLs have been developed for these impairments in the watershed.

Stakeholders within the area under the jurisdiction of the Los Angeles Water Board have formed several long-range water planning groups and have developed IRWM Plans under Propositions 50 and 84. Stakeholders in the Los Angeles County portion of the Santa Clara River Watershed joined together to develop the IRWM Plan for the Upper Santa Clara River. They work closely with the IRWM group in the lower watershed, led by the Watersheds Coalition for Ventura County, which has a Santa Clara River Watershed Committee for IRWM Plan implementation in that watershed. Permittees within this watershed also participated in the development of a Storm Water Resource Plan pursuant to Water Code section 10563 et seq. in order to be eligible to apply for state funding for stormwater and dry weather runoff projects to improve water quality.

Calleguas Creek Watershed Management Area. Calleguas Creek and its major tributaries: Revolon Slough, Conjeo Creek, Arroyo Conejo, Arroyo Santa Rosa, and Arroyo Simi, drain a watershed area of 343 square miles (219,520 acres) in southern Ventura County and a small portion of western Los Angeles County (Attachment B Figure B-5). The northern boundary is formed by the Santa Susana Mountains, South Mountain, and Oak Ridge; the southern boundary is formed by the Simi Hills and Santa Monica Mountains. Land uses vary throughout the watershed. Urban development is generally restricted to the city limits of Simi Valley, Moorpark, Thousand Oaks, and Camarillo. Although some residential development has occurred along the slopes of the watershed, most upland areas are still open space. Agricultural activities, primarily cultivation of orchards and row crops, are spread out along valleys and on the Oxnard Plain.

Mugu Lagoon, located at the mouth of the watershed, is one of the few remaining significant saltwater wetland habitats in southern California. The Point Mugu Naval Air Base is located in the immediate area. The surrounding Oxnard Plain supports a large variety of agricultural crops. The lagoon borders on an Area of Special Biological

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Significance (ASBS) and supports a great diversity of wildlife including several endangered birds and one endangered plant species. Except for the military base, the lagoon area is relatively undeveloped.

Various reaches of the Calleguas Creek Watershed are on the 2014/2016 Clean Water Act section 303(d) list of impaired water bodies for ammonia, chlordane, chloride, legacy pesticides, metals, bacteria, nutrients, and trash, among other pollutants.

Stakeholders within the area under the jurisdiction of the Los Angeles Water Board have formed several long-range water planning groups and have developed IRWM Plans under Propositions 50 and 84. Permittees within this watershed also participated in the development of a Storm Water Resource Plan pursuant to Water Code section 10563 et seq. in order to be eligible to apply for state funding for stormwater and dry weather runoff projects to improve water quality.

Santa Monica Bay Watershed Management Area. The Santa Monica Bay Watershed Management Area encompasses an area of 414 square miles (264,960 acres) (Attachment B Figure B-6). Its borders reach from the crest of the Santa Monica Mountains on the north and from the Ventura-Los Angeles County line to downtown Los Angeles. From there it extends south and west across the Los Angeles plain to include the area east of Ballona Creek and north of the Baldwin Hills. A narrow strip of land between Playa del Rey and Palos Verdes drains to the Bay south of Ballona Creek. The WMA includes several subwatersheds, the two largest being Malibu Creek to the northwest and Ballona Creek to the south. The Malibu Creek area contains mostly undeveloped mountain areas, large acreage residential properties, and many natural stream reaches, while Ballona Creek is predominantly channelized and drains a highly developed watershed.

Many of the Santa Monica Bay beaches are identified on the 2014/2016 Clean Water Act section 303(d) list of impaired water bodies for indicator bacteria. Santa Monica Bay offshore and nearshore is on the 2014/2016 Clean Water Act section 303(d) list of impaired water bodies for trash, DDTs, PCBs, arsenic, and mercury. The elevated bacterial indicator densities during both dry and wet weather are causing impairments of the REC-1 and REC-2 designated beneficial uses of the Santa Monica Bay beaches.

The debris and elevated concentrations of DDT and PCBs are causing impairments to the IND, NAV, REC-1, REC-2, COMM, EST, MAR, BIOL, MIGR, WILD, RARE, SPWN, SHELL, and WET designated beneficial uses of the Santa Monica Bay. One of the impacts in marine habitats is sediment contamination and damage to marine life that the contaminants cause when they are released from the sediment (through natural fluctuations or through disturbance of the sediment) into the food chain.

Bioaccumulation of DDT in white croaker, Dover sole, and California brown pelicans are well-known examples of the impacts caused by sediment contamination.

Malibu Creek subwatershed: The Malibu Creek subwatershed drains an area of about 109 square miles (69,760 acres) (Attachment B Figure B-6a). Approximately two-thirds of this subwatershed lies in Los Angeles County and the remaining third lies in Ventura County. Much of the land is part of the Santa Monica Mountains National Recreation Area and is under the purview of the National Parks Service.

The watershed borders the eastern portion of Ventura County to the northwest and the Los Angeles River watershed to the east. Major tributaries include Cold Creek, Lindero Creek, Las Virgenes Creek, Medea Creek, and Triunfo Creek. The Malibu Creek watershed also includes lakes such as Lake Sherwood, Westlake Lake, Malibou Lake, and Lake Lindero. Located at the end of and receiving flows from

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Malibu Creek is the 40-acre Malibu Lagoon. The Malibu Creek subwatershed land uses are 88% open space, 3% commercial/light industry, 9% residential, and less than 1% public.

Malibu Lagoon supports two important plant communities, the coastal salt marsh and coastal strand, and is an important refuge for migrating birds (over 200 species of birds have been observed). Perennial streams in Malibu Canyon support oak and riparian woodlands. Malibu Creek is also the southernmost watercourse in California where steelhead trout continue to spawn in relatively large numbers.

The Malibu Creek Watershed is on the 2014/16 Clean Water Act section 303(d) list of impaired water bodies for bacteria, nutrients, selenium, sulfates, sediment/siltation, and trash. Elevated bacterial indicator densities are causing impairment of the REC-1 and REC-2 designated beneficial uses of Malibu Creek, Malibu Lagoon, and the adjacent beaches. Excess nutrients and sedimentation/siltation are causing impairments to the REC-1, REC-2, WARM, COLD, EST, MAR, WILD, RARE, MIGR, and SPWN designated beneficial uses of waterbodies in the Malibu Creek Watershed. Selenium is causing impairments to the WARM designated beneficial uses of waterbodies in the Malibu Creek Watershed. Trash is causing impairments to the REC-1, REC-2, WARM, COLD, MIGR, WILD, RARE, SPWN, and WET designated beneficial uses of the waterbodies in the Malibu Creek Watershed.

Marina del Rey subwatershed: The Marina del Rey subwatershed is approximately 2.7 square miles (1,728 acres) located adjacent to the mouth of Ballona Creek (Attachment B, Figure B-6b). The Marina del Rey subwatershed is highly developed at 80%; the remaining 20% is split between water and open/recreation land uses.

Marina del Rey is on the 2014/2016 Clean Water Act section 303(d) list for bacteria and sediment concentrations of copper, lead, zinc, DDT, PCBs, chlordane, and sediment toxicity. The elevated bacterial indicator densities are causing impairment of the REC-1 and REC-2 designated beneficial uses at Marina del Rey Harbor Mothers’ Beach and back basins. The toxic pollutants are causing impairments to the REC-1, MAR, WILD, COMM, and SHELL designated beneficial uses of the Marina del Rey Harbor.

Ballona Creek subwatershed: Ballona Creek and its tributaries drain a subwatershed of about 128 square miles (81,920 acres) (Attachment B, Figure B6c). Ballona Creek is the largest drainage tributary to Santa Monica Bay and discharges to the ocean adjacent to the entrance of the Marina del Rey Harbor.

The watershed boundary extends in the east from the crest of the Santa Monica Mountains southward and westward to the vicinity of central Los Angeles and thence to Baldwin Hills. Tributaries of Ballona Creek include Centinela Creek, Sepulveda Canyon Channel, Benedict Canyon Channel, and numerous other storm drains. Ballona Creek is concrete lined upstream of Centinela Boulevard. All of its tributaries are either concrete channels or covered culverts. The channel downstream of Centinela Boulevard is trapezoidal composed of grouted rip-rap side slopes and an earth bottom. The urbanized areas of Ballona Creek account for 80% of the watershed; the partially developed foothill and mountains make up the other 20%.

The watershed encompasses an area that historically consisted of extensive wetlands. The current-day Ballona Wetlands are located near the mouth of the

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creek and represents one of the few remaining regionally significant coastal wetlands along Santa Monica Bay. The complex of wetlands is a mixture of habitats dominated by coastal salt marsh; several special status species are supported there including Belding’s Savannah Sparrow. In 2004, the State of California acquired ownership of this remaining wetland area (600 acres (243 hectares) in total).

Ballona Creek and Ballona Creek Estuary are on the 2014/2016 Clean Water Act section 303(d) list for trash, toxicity, bacteria, historic pesticides, PCBs, PAHs, and metals. The Ballona Creek Wetlands is on the 2014/2016 Clean Water Act section 303(d) list for trash, exotic vegetation, habitat alterations, and reduced tidal flushing. Trash is causing impairments to the REC-1, REC-2, WARM, WILD, EST, MAR, RARE, MIGR, SPWN, COMM, WET, and COLD designated beneficial uses of Ballona Creek. The metals, pesticides, PCBs, and PAHs in sediments and dissolved copper, dissolved lead, and dissolved zinc, are causing impairments to the REC-1, REC-2, EST, MAR, WILD, RARE, MIGR, SPWN, COMM, and SHELL designated beneficial uses of Ballona Creek Estuary, Ballona Creek, and Sepulveda Channel. The elevated bacterial indicator densities are causing impairment of the REC-1, LREC-1, and REC-2 designated beneficial uses of Ballona Creek, Sepulveda Channel, and Ballona Estuary. The excess sediment and invasive non-native vegetation are causing impairments to the EST, MIGR, RARE, REC-1, REC-2, SPWN, WET, and WILD designated beneficial uses of the Ballona Creek Wetlands.

Dominguez Channel and Greater Harbor Waters Watershed Management Area.

The Dominguez Channel and Los Angeles/Long Beach Harbors Watershed Management Area (Dominguez WMA) is in the southern portion of the Los Angeles Basin (Attachment B Figure B-7). It covers an area of approximately 121 square miles (77,440 acres). Los Angeles Harbor is 7,500 acres and the Long Beach Harbor is 7,600 acres; together they have an open water area of approximately 8,128 acres. Along the northern portion of San Pedro Bay is a natural embayment formed by a westerly extension of the coastline which contains both harbors, with the Palos Verdes Hills the dominant onshore feature. The 15-mile-long Dominguez Channel drains a densely urbanized area to Inner Los Angeles Harbor. Despite its industrial nature, contaminant sources, disrupted wetlands habitat, and low flushing ability, the inner harbor area supports diverse fish and benthic populations and provides a protected nursery area for juvenile fish. The California least tern, an endangered species, nests in one part of the harbor complex. Some wetlands persist in the Machado Lake area. The outer part of both harbors (the greater San Pedro Bay within the breakwaters) has been less disrupted and supports a great diversity of marine life and a large population of fish. It is also open to the ocean at its eastern end and receives much greater flushing than the inner harbors.

Various reaches of the Dominguez WMA are on the 2014/2016 Clean Water Act section 303(d) list of impaired water bodies for metals, DDT, PCBs, PAHs, historic pesticides, coliform, and sediment toxicity. The elevated bacteria indicator densities are causing impairments to the SHELL, REC-1, and REC-2 designated beneficial uses of Los Angeles Harbor. The elevated levels of metals and organics are causing impairments to beneficial uses designated in these waters to protect aquatic life, including MAR and RARE. In addition, the elevated levels are causing impairments in the estuaries, which are designated with SPWN, MIGR, and WILD beneficial uses. Dominguez Channel also has an existing designated use of WARM and the Los Angeles River Estuary has the

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designated use of WET. Beneficial uses associated with human use of these waters that are impaired due to the elevated concentrations of metals and organics include REC-1, REC-2, IND, NAV, COMM, and SHELL.

Machado Lake subwatershed: Machado Lake is a subwatershed of the Dominguez Channel Watershed (Attachment B, Figure B-7a). Wilmington Drain discharges into Machado Lake from the north; the channel is concrete lined from its origin south of Sepulveda Boulevard (between Normandie and Vermont Avenues) to where it crosses under the Harbor Freeway north of Lomita Boulevard.

South of this point it changes to a soft bottom with natural side banks to where it empties into Machado Lake. Habitat in this part of the drain includes mature riparian woodland, riparian scrub, freshwater marsh, and weedy vegetation. The area is well-utilized by birds
Machado Lake is listed on the 2014/2016 Clean Water Act section 303(d) list for trash, nutrients, PCBs and historic pesticides. Trash, nutrients and toxic pollutants are causing impairments to the WARM, WET, RARE, WILD, REC-1 and REC-2 designated beneficial uses of Machado Lake. TMDLs have been adopted by the Los Angeles Water Board for trash, nutrients, PCBs and pesticides for Machado Lake. The point sources of trash and nutrients into Machado Lake are stormwater and non-stormwater discharges from the MS4. Stormwater discharges occur through the following sub-drainage systems: Drain 553, Wilmington Drain, Project 77/510, and Walteria Lake Retention Basin.

Los Angeles River Watershed Management Area. The Los Angeles River Watershed Management Area drains a watershed of 824 square miles (527,360 acres) (Attachment B Figure B-8) in Los Angeles County and a small portion of south eastern Ventura County. Approximately 1.2 acres of Simi Valley, which is in Ventura County, drains to the Los Angeles River Watershed and is mainly undeveloped. The Los Angeles River WMA is one of the largest in the Los Angeles Region and is also one of the most diverse in terms of land use patterns. Approximately 324 square miles of the watershed are covered by forest or open space land including the area near the headwaters, which originate in the Santa Monica, Santa Susana, and San Gabriel Mountains. The remainder of the watershed is highly developed. There are approximately 205 miles of engineered channels within the Los Angeles River Watershed. A 6.8-mile (11-kilometer) long reach in the narrows area (in the middle portion of the river system), where ground water rises into the streambed, is mostly unlined along the stream bottom and provides natural habitat for fish and other wildlife in an otherwise concrete conveyance. The river flows through the San Fernando Valley past heavily developed residential and commercial areas. Major tributaries to the river in the San Fernando Valley are the Pacoima Wash, Tujunga Wash (both drain portions of the Angeles National Forest in the San Gabriel Mountains), Burbank Western Channel, and Verdugo Wash (both drain the Verdugo Mountains). From the Arroyo Seco, north of downtown Los Angeles, to the confluence with the Rio Hondo, the river flows through industrial and commercial areas and is bordered by rail yards, freeways, and major commercial and government buildings. The river is hydraulically connected to the San Gabriel River Watershed by the Rio Hondo through the Whittier Narrows Reservoir. Flows from the San Gabriel River and Rio Hondo merge at this reservoir during larger flood events and thus flows from the San Gabriel River Watershed may impact the Los Angeles River. From the Rio Hondo to the Pacific Ocean, the river flows through industrial, residential, and commercial areas. The Los Angeles River tidal prism/estuary begins in Long Beach at

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Willow Street and runs approximately three miles before joining with Queensway Bay.

The channel has a soft bottom in this reach with concrete-lined sides.

A number of lakes are also part of the Los Angeles River WMA, including Legg Lake, Peck Road Park, Belvedere Park, Hollenbeck Park, Lincoln Park, and Echo Park Lakes as well as Lake Calabasas. These lakes are heavily used for recreational purposes.

Various reaches and lakes within the Los Angeles River WMA are on the 2014/2016 Clean Water Act section 303(d) list of impaired water bodies for trash, nitrogen compounds and related effects (ammonia, nitrate, nitrite, algae, pH, odor, and scum), metals (copper, cadmium, lead, zinc, aluminum and selenium), bacteria, and historic pesticides. Beneficial uses impaired by trash are REC-1, REC-2, WARM, WILD, EST, MAR, RARE, MIGR, SPWN, COMM, WET and COLD. The excess nitrogen compounds are causing impairments to the REC-1, REC-2, WARM, COLD, and WILD beneficial uses. Excess metals and historic pesticides are causing impairments to the WILD, RARE, WARM, WET, and GWR beneficial uses. Elevated indicator bacteria densities are causing impairments to the REC-1 and REC-2 beneficial uses.

San Gabriel River Watershed Management Area. The San Gabriel River Watershed (SGR WMA) receives drainage from a 689-square mile (440,960 acre) area of eastern Los Angeles County (Attachment B, Figure B-9). The main channel of the San Gabriel River is approximately 58 miles long. Its headwaters originate in the San Gabriel Mountains with the East, West, and North Forks. The river empties to the Pacific Ocean at the Los Angeles and Orange Counties boundary in Long Beach. The main tributaries of the river are Big Dalton Wash and Little Dalton Wash, San Dimas Wash, Walnut Creek, San Jose Creek, Fullerton Creek, and Coyote Creek. Part of the Coyote Creek subwatershed is in Orange County and is under the authority of the Santa Ana Water Board.8 A number of lakes and reservoirs are also part of the SGR WMA, including Puddingstone Reservoir. Land use in the watershed is diverse and ranges from 8 The Orange County portion of the Coyote Creek subwatershed comprises 86 square miles. MS4 discharges within the Orange County portion of the Coyote Creek subwatershed are within the jurisdiction of the Santa Ana Water Board and are not covered by the Order. These MS4 discharges, which drain into Coyote Creek, eventually reach the San Gabriel River within the boundaries of the Los Angeles Water Board’s jurisdiction. Sources of MS4 discharges from Orange County to the San Gabriel River include the following. The Orange County Flood Control District (OCFCD) owns and operates the Los Alamitos Retarding Basin and Pumping Station (Los Alamitos Retarding Basin). The Los Alamitos Retarding Basin is within the San Gabriel River Watershed and is located adjacent to the Los Angeles and Orange County boundary. The majority of the 30-acre Los Alamitos Retarding Basin is in Orange County; however, the northwest corner of the facility is in Los Angeles County. Stormwater and nonstormwater discharges, which drain to the Los Alamitos Retarding Basin, are pumped to the San Gabriel River Estuary (SGR Estuary) through pumps and subterranean piping. The pumps and discharge point are in Los Angeles County. The OCFCD pumps the water within the Los Alamitos Retarding Basin to the SGR Estuary through four discharge pipes, which are covered by tide gates. The discharge point is located approximately 700 feet downstream from the 2nd Street Bridge in Long Beach. The total pumping capacity of the four pumps is 800 cubic feet per second (cfs). There is also a 5 cfs sump pump that discharges nuisance flow continuously to the SGR Estuary though a smaller diameter uncovered pipe.

The discharge from the Los Alamitos Retarding Basin is covered under the Orange County Municipal NPDES Storm Water Permit (NPDES Permit No. CAS618030, Santa Ana Regional Water Quality Control Board Order No. R8-2009-0030), which was issued to the County of Orange, Orange County Flood Control District and Incorporated Cities on May 22, 2009. The Orange County MS4 Permit references the San Gabriel River Metals and Selenium TMDL (Metals TMDL). The waste load allocations listed in the Metals TMDL for Coyote Creek are included in the Orange County MS4 Permit. However, the Orange County MS4 Permit does not contain the dry weather copper waste load allocations assigned to the Estuary.

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predominantly open space in the upper watershed to urban land uses in the middle and lower parts of the watershed.

The watershed consists of extensive areas of undisturbed riparian and woodland habitats in its upper reaches. Much of the watershed of the West Fork and East Fork of the river is set aside as a wilderness area; other areas in the upper watershed are subject to heavy recreational use. The upper watershed also contains a series of flood control dams. The watershed is hydraulically connected to the Los Angeles River through the Whittier Narrows Reservoir (normally only during high storm flows). The lower part of the river flows through a concrete-lined channel in a heavily urbanized portion of the Los Angeles Coastal Plain, before becoming a soft bottom channel once again near the ocean in the City of Long Beach. Flow in these lower reaches is dominated by effluent from several municipal wastewater treatment facilities and MS4 discharges.

Various reaches and lakes of the SGR WMA are on the 2014/2016 Clean Water Act section 303(d) list of impaired water bodies due to bacteria, trash, nitrogen, phosphorus, historic pesticides, PCBs, and metals (copper, lead, selenium, and zinc). Beneficial uses impaired by trash are REC-1, REC-2, WARM, COLD, and WILD. Metals and historic pesticides loadings are causing impairments of the WILD, WARM, COLD, RARE, EST, MAR, MIGR, SPWN, WET, MUN, IND, AGR, GWR, and PROC beneficial uses. The excess nitrogen and phosphorus are causing impairments to the REC-1, REC-2, WARM, COLD, and WILD beneficial uses. Elevated indicator bacteria densities are causing impairments to the REC-1 and REC-2 beneficial uses.

Los Cerritos Channel and Alamitos Bay Watershed Management Area. The Los Cerritos Channel is concrete-lined above the tidal prism and drains a small but densely urbanized area of east Long Beach (Attachment B, Figure B-10). The watershed covers an area of approximately 37 square miles (23,680 acres) out of which 5 square miles (3,200 acres) is Alamitos Bay. The Los Cerritos WMA is located between the Los Angeles and San Gabriel Rivers and drains to the same general area as the San Gabriel River. There is also a minor hydraulic connection between the lower San Gabriel River and Los Cerritos Channel due to the location of a power plant intake within the Long Beach Marina; the discharge from this facility is into the San Gabriel River estuary. The Los Cerritos Channel’s tidal prism starts at Anaheim Road and connects with Alamitos Bay through the Marine Stadium; the wetlands connect to the Channel a short distance from the lower end of the Channel. The wetland, and portion of the channel near the wetland, is an overwintering site for a great diversity of birds despite its small size. An endangered bird species, the Belding's Savannah Sparrow, may nest there and an area adjacent to the wetlands is a historic least tern colony site. A small marina is located in the channel, which is also used by rowing teams and is a popular fishing area. Alamitos Bay is composed of the Marine Stadium, a recreation facility built in 1932; Long Beach Marina; a variety of public and private berths; and the Bay proper. A small bathing lagoon, Colorado Lagoon located entirely in Long Beach, has a tidal connection with the Bay and is used by overwintering migratory birds. The majority of land use in this WMA is high density residential.

Los Cerritos Channel is on the 2014/2016 Clean Water Act section 303(d) List of impaired water bodies for metals (copper, zinc, and lead), trash, ammonia, pH, chlordane, and bacteria. Alamitos Bay is on the 2014/2016 Clean Water Act section 303(d) List of impaired water bodies for bacteria and dissolved oxygen. Beneficial uses impaired by these constituents in the Los Cerritos Channel include WILD, REC2 and WARM.

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Middle Santa Ana River Watershed Management Area. The Middle Santa Ana River Watershed Management Area (MSAR WMA) covers approximately 488 square miles (312,320 acres) and lies mostly in San Bernardino and Riverside counties; however, a small part of Los Angeles County is also included. The area of Los Angeles County, which lays in the MSAR WMA, includes portions of the cities of Pomona (12.3 square miles), Claremont (8.4 square miles), and Diamond Bar (0.7 square miles) and unincorporated Los Angeles County (12.3 square miles). The MSAR WMA is comprised of three subwatersheds. The subwatershed that includes portions of Pomona and Claremont is the Chino Basin Subwatershed. Surface drainage from Pomona and Claremont is generally southward toward San Antonio Creek, which is tributary to Chino Creek, which feeds into the Prado Flood Control Basin.

Various reaches of the MSAR WMA, including Chino Creek, are listed on the 2014/16 Clean Water Act section 303(d) list for bacteria. Elevated bacterial indicator densities are causing impairments of the REC-1 and REC-2 beneficial uses for the Santa Ana River Reach 3, Chino Creek Reaches 1 and 2, Mill Creek (Prado Area), Cucamonga Creek Reach 1, and Prado Park Lake.

The Santa Ana River Watershed is a major WMA within the Santa Ana Water Board jurisdiction. However, 30.5 square miles of the Santa Ana River Watershed falls within the Los Angeles Water Board’s jurisdiction and therefore will be addressed in the Order except as follows. Per an agreement between the Los Angeles Water Board and the Santa Ana Water Board dated May 31, 2013, the Santa Ana Water Board is designated as the regulator of discharges of bacteria by the cities of Claremont and Pomona through their MS4s to receiving waters within the Santa Ana River Watershed addressed by the Middle Santa Ana River Watershed Bacterial TMDL.9 Per this agreement, both the Santa Ana Water Board and Los Angeles Water Board have the authority to enforce the terms of any MS4 permit issued to the cities of Claremont and Pomona if the MS4 discharges occur with the Los Angeles Water Board’s geographic jurisdiction.

C. Description of the Permittees’ MS4s
The Permittees’ MS4s, like many MS4s in the nation, are based on regional floodwater management systems that use both natural and altered water bodies to achieve flood management goals. Most Permittees’ MS4s comprise a large interconnected system used by multiple municipalities. This extensive system conveys stormwater and nonstormwater across municipal boundaries where it is commingled within the MS4 and then discharged to receiving water bodies.

The area covered under the Order contains an extensive drainage network that serves incorporated and unincorporated areas in every Watershed Management Area within the Los Angeles Region. The Los Angeles Region comprises all basins draining into the Pacific Ocean between the southeasterly boundary, located in the westerly part of Ventura County, of the watershed of Rincon Creek and a line which coincides with the southeasterly boundary of Los Angeles County from the ocean to San Antonio Peak and follows thence the divide between San Gabriel River and Lytle Creek drainages to the divide between Sheep Creek and San Gabriel River drainages. (California Water Code § 13200(d)). Maps depicting the major drainage infrastructure within the area covered under the Order are included in Attachment C. Rough estimates based on GIS data and other information from Permittees indicate that the Los Angeles Region has 9 Attachment D to Order No. R8-2013-0043.

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an over 7,300-mile subsurface network of MS4 infrastructure (including main storm drain lines, lateral lines, and culverts). Table F-2 below provides approximated information on the extent of select Permittees’ MS4-related infrastructure based on available information carried over from the previous permits, information provided by Ventura County Permittees upon request, GIS data, and annual reports.

Table F-2. Select Permittees’ MS4-Related Infrastructure10 Permittee
Area
(Square
Miles)
Catch
Basins
Storm Drain
Length
(miles)
Open
Channel
Length
(miles)
Ventura
County
Watershed
Protection
District

8.9 0 59.5 219
Ventura
County 32.4 1421 35.6 0.01
Camarillo 19.86 1521 60 5.78
Fillmore 3.2 208 18.2 5
Moorpark 12.5 737 57.0 0
Ojai 4.4 172 4.1 6
Oxnard 27.1 3644 167.3 10.62
Port
Hueneme 4.5 234 6.4 3
Santa Paula 5.5 520 18.5 1
Simi Valley 42.3 1783 107.5 3
Thousand
Oaks 55.4 3293 205.4 2
Ventura 22.2 1847 139.6 9
Long Beach 47.7 3800 180 49

LACFCD /
Los Angeles
County
3100 88000 3500 500
City of Los
Angeles 469 30000 1600 31
El Monte 10 316 11 0.4
Glendale 30.6 1045 136.7 14.4
Inglewood 9 1157 12 0
Pasadena 26 1050 30 7.3
10 All numbers in this table are the Permittees’ best estimates based on knowledge of their storm drainage system; these estimates do not include all conveyances subject to the definition of an MS4 under federal regulations. Estimates can vary due to definition of terms, and GIS categorization and mapping accuracy.

These are subject to change as data is field verified and new infrastructure is constructed or decommissioned by Permittees.

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Permittee
Area
(Square
Miles)
Catch
Basins
Storm Drain
Length
(miles)
Open
Channel
Length
(miles)
Santa
Monica 8.3 850 68.3 0.5
Torrance 20 2000 20 3
Additionally, there are numerous stormwater treatment facilities, including stormwater retention basins and stormwater detention basins, within the region. Some examples of existing stormwater treatment facilities include the Santa Monica Urban Runoff Recycling Facility (SMURRF) (City of Santa Monica), Marie Canyon (City of Malibu), and Paradise Cove (City of Malibu). Some examples of existing stormwater retention/detention basins include Oxford Basin (County of Los Angeles), Amie Retention Basin (Torrance), and Louie Pompei Park (Glendora).

Stormwater and non-stormwater are conveyed through the MS4s and ultimately discharge into receiving waters of the Los Angeles Region. MS4s subject to the Order receive stormwater and non-stormwater flows from various sources, including conveyances owned by the Permittees covered by the Order and other public agencies, NPDES permitted discharges, discharges authorized by the U.S. EPA (including discharges subject to a decision document approved pursuant to the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA)), rising ground water, and natural flows.

The volume of stormwater and non-stormwater conveyed through the MS4s can be estimated by looking at impervious area data. Detailed data on impervious area is unavailable for Ventura County Permittees at the time of this permit development.

However, per the permit reapplication package (or Report of Waste Discharge, also known as the ROWD), Ventura County has 200,000 acres of developed land. Specific data for Los Angeles County, however, is available through the Safe, Clean Water Program (Measure W) information provided by Los Angeles County and LACFCD and is presented in Table F-3 below.

Table F-3. Los Angeles County Impervious Area
Permittee Impervious Area (ac)
Agoura Hills 840
Alhambra 2,066
Arcadia 2,361
Artesia 491
Azusa 1,526
Baldwin Park 1,717
Bell 755
Bell Gardens 757
Bellflower 1,936
Beverly Hills 1,290
Bradbury 143
Burbank 3,407

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Permittee Impervious Area (ac)
Calabasas 1,089
Carson 6,432
Cerritos 2,363
Claremont 1,388
Commerce 2,974
Compton 2,855
County of Los Angeles 28,769
Covina 1,757
Cudahy 416
Culver City 1,280
Diamond Bar 2,060
Downey 3,406
Duarte 604
El Monte 2,714
El Segundo 2,059
Gardena 1,982
Glendale 3,939
Glendora 2,160
Hawaiian Gardens 300
Hawthorne 1,903
Hermosa Beach 372
Hidden Hills 235
Huntington Park 1,001
Industry 4,278
Inglewood 2,386
Irwindale 1,164
La Cañada Flintridge 914
La Habra Heights 417
La Mirada 2,275
La Puente 816
La Verne 1,430
Lakewood 2,597
Lawndale 537
Lomita 535
Long Beach 11,150
Los Angeles 87,031
Lynwood 1,351
Malibu 1,035
Manhattan Beach 995
Maywood 407

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Permittee Impervious Area (ac)
Monrovia 1,247
Montebello 2,286
Monterey Park 1,803
Norwalk 2,634
Palos Verdes Estates 603
Paramount 1,586
Pasadena 3,613
Pico Rivera 2,278
Pomona 4,598
Rancho Palos Verdes 1,643
Redondo Beach 1,738
Rolling Hills 282
Rolling Hills Estates 448
Rosemead 1,395
San Dimas 1,467
San Fernando 642
San Gabriel 1,057
San Marino 540
Santa Clarita 8,301
Santa Fe Springs 3,636
Santa Monica 1,903
Sierra Madre 354
Signal Hill 686
South El Monte 1,065
South Gate 2,419
South Pasadena 590
Temple City 1,057
Torrance 5,738
Vernon 2,592
Walnut 1,163
West Covina 3,213
West Hollywood 630
Westlake Village 565
Whittier 2,853
Grand Total 275,290
The Order applies to all 99 Permittees within the nine major coastal WMAs under the jurisdiction of the Los Angeles Water Board. These 99 Permittees include 95 cities, two counties, and two flood control districts. The two flood control districts are described in more detail, below, as the nature and scope of their authorities is different from the other 97 Permittees.

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D. Description of Flood Control District Permittees
In 1915, the California Legislature enacted the Los Angeles County Flood Control Act, establishing the Los Angeles County Flood Control District (LACFCD). The objectives and purposes of the Act are to provide for the control and conservation of flood, storm and other waste waters within the flood control district. Among its other powers, LACFCD also has the power to preserve, enhance, and add recreational features to lands or interests in lands contiguous to its properties for the protection, preservation, and use of the scenic beauty and natural environment for the properties or the lands.

LACFCD is governed, as a separate entity, by the County of Los Angeles Board of Supervisors.

LACFCD’s system includes the majority of drainage infrastructure within incorporated and unincorporated areas of Los Angeles County in every watershed, including approximately 500 miles of open channel, 3,500 miles of underground drains, and an estimated 88,000 catch basins. Portions of LACFCD’s current system were originally unmodified natural rivers and water courses. LACFCD’s system conveys both storm and non-stormwater throughout Los Angeles County. Other Permittees’ MS4s within Los Angeles County connect and discharge to LACFCD’s system.

The Ventura County Watershed Protection District (VCWPD) was formed, in part, to provide for the control and conservation of flood and stormwaters, and for the protection and maintenance of watercourses, watersheds, and life and property within the VCWPD from damage or destruction from storm flows or flooding. The VCWPD was originally established on September 12, 1944 as the “Ventura County Flood Control District.” On January 1, 2003, per California Water Code Appendix, Chapter 46, the name was changed to the Ventura County Watershed Protection District to reflect changes in community values, regulatory requirements, and funding opportunities. The change in name also reflected VCWPD’s desire to emphasize integrated watershed management and to solve flood control problems with environmentally sound approaches.

VCWPD’s system includes infrastructure within incorporated and unincorporated areas of Ventura County in every watershed. VCWPD owns/operates approximately 219 miles of open channel and 60 miles of storm drains.

Unlike other Permittees, including the counties of Los Angeles and Ventura, LACFCD and VCWPD do not own or operate any municipal sanitary sewer systems, public streets, roads, or highways. LACFCD and VCWPD also have no planning, zoning, development permitting or other land use authority over industrial or commercial facilities, or new developments or re-development projects located in any incorporated or unincorporated areas within their service area. Nonetheless, as owners and operators of MS4s, LACFCD and VCWPD are required by federal law to control pollutant discharges into and from their MS4s, including but not limited to the ability to control through interagency agreements among co-Permittees and other owners of MS4s the contribution of pollutants from one portion of the MS4 to another portion of the MS4.

Under Order No. R4-2010-0108, VCWPD was designated the Principal Permittee.

However, in the Order, the role of Principal Permittee has been eliminated, since the Order applies to Permittees in both Los Angeles and Ventura Counties. Furthermore, under Order No. R4-2012-0175, LACFCD was prescribed separate requirements for minimum control measures. The Order generally does not include separate requirements for LACFCD or VCWPD; however, it notes where certain provisions do not apply (e.g., provisions relating to the industrial and commercial facilities inspection

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programs, planning and land development programs, and new development and redevelopment projects within their jurisdictional boundaries).

E. Nature of MS4 Discharges as a Source of Pollutants to Receiving Waters and Need for Regulation
Stormwater and non-stormwater discharges consist of surface runoff generated from various land uses, which is conveyed via the MS4 and ultimately discharge to surface waters throughout the region. Discharges of stormwater and non-stormwater through the MS4s within the Los Angeles Region convey pollutants to surface waters.

The quality of stormwater and non-stormwater discharges from MS4s is fundamentally important to public health, the health of the environment, and the quality of life in Southern California. Polluted stormwater and non-stormwater discharges from MS4s are a leading cause of water quality impairment in the Los Angeles Region. Stormwater and non-stormwater discharges are often contaminated with pesticides, fertilizers, fecal indicator bacteria and associated pathogens, trash, oil and other automotive byproducts, and many other toxic substances generated by activities in the urban environment. Water that flows over streets, parking lots, construction sites, and industrial, commercial, residential, and municipal areas convey these pollutants through the MS4 directly into receiving waters of the Region.

The water quality impacts and resulting ecosystem impacts and increased public health risks from MS4 discharges that affect receiving waters nationwide and throughout the jurisdiction of the Los Angeles Water Board, including its coastline, are well documented. One of the seminal studies on stormwater impacts was the National Urban Runoff Program (NURP) Study (U.S. EPA 1983), which showed that MS4 discharges from residential, commercial, and light industrial areas contain significant loadings of total suspended solids and other pollutants. The NURP Study also found that pollutant levels from illicit discharges were high enough to significantly degrade receiving water quality, and threaten aquatic life, wildlife, and human health. Many studies since continue to support the conclusions of the NURP Study. The general findings and conclusions of the NURP Study are reiterated in the more recent 2008 National Research Council report “Urban Runoff Management in the United States” as well as in a regional study, “Sources, Patterns and Mechanisms of Storm Water Pollutant Loading from Watersheds and Land Uses of the Greater Los Angeles Area, California,” SCCWRP Technical Report 510 (2007), funded in large part by the Los Angeles Water Board.

Some of the conclusions of the 2007 regional study, which largely remain true today (as demonstrated by an analysis of monitoring data collected under the three previous permit terms), were as follows:
• Storm water runoff from watershed and land use-based sources is a significant contributor of pollutant loading and often exceeds water quality standards. High pollutant concentrations were observed throughout the study at both mass emission (ME) and land use (LU) sites. Pollutant concentrations frequently exceeded water quality standards.
• Storm water Event Mean Concentrations (EMCs), fluxes and loads were substantially lower from undeveloped open space areas when compared to developed urbanized watersheds. Storms sampled from less developed watersheds produced pollutant EMCs and fluxes that were one to two orders of magnitude lower than comparably sized storms in urbanized watersheds.

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Furthermore, the higher fluxes from developed watersheds were generated by substantially less rainfall than the lower fluxes from the undeveloped watersheds, presumably due to increased impervious surface area in developed watersheds.
• The Los Angeles region contributed a similar range of storm water runoff pollutant loads as that of other regions of the United States. Comparison of constituent concentrations in storm water runoff from land use sites from this study reveal median EMCs that are comparable to U.S. averages reported in the National Stormwater Quality Database (NSQD; Pitt et al., 2003). Comparison to the NSQD data set provides insight to spatial and temporal patterns in constituent concentrations in urban systems. Similarities between levels reported in the NSQD and this study suggest that land-based concentrations in southern California storm water are generally comparable to those in other parts of the country.
• Peak concentrations for all constituents were observed during the early part of the storm. Constituent concentrations varied with time over the course of storm events. For all storms sampled, the highest constituent concentrations occurred during the early phases of storm water runoff with peak concentrations usually preceding peak flow. Although the pattern of an early peak in concentration was comparable in both large and small developed watersheds, the peak concentration tended to occur later in the storm and persist for a longer duration in the smaller developed watersheds. Therefore, monitoring programs must capture the early portion of storms and account for intra-storm variability in concentration in order to generate accurate estimates of EMC and contaminant loading. Programs that do not initiate sampling until a flow threshold has been surpassed may severely underestimate storm EMCs.
• Highest constituent loading was observed early in the storm season with intraannual variability driven more by antecedent dry period than amount of rainfall.

Seasonal differences in constituent EMCs and loads were consistently observed at both ME and LU sites. In general, early season storms (October - December) produce significantly higher constituent EMCs and loads than late season storms (April - May), even when rainfall quantity was similar. This suggests that the magnitude of constituent load associated with storm water runoff depends, at least in part, on the amount of time available for pollutant build-up on land surfaces. The extended dry period that typically occurs in arid climates such as southern California maximizes the time for constituents to build-up on land surfaces, resulting in proportionally higher concentrations and loads during initial storms of the season.

The Natural Resources Defense Council (NRDC) 1999 Report, "Stormwater Strategies, Community Responses to Runoff Pollution” identifies two main causes of the storm water pollution problem in urban areas. Both causes are directly related to development in urban and urbanizing areas:
• Increased volume and velocity of surface runoff. There are three types of human-made impervious covers that increase the volume and velocity of runoff:
(i) rooftop, (ii) transportation imperviousness, and (iii) non-porous (impervious) surfaces. As these impervious surfaces increase, infiltration will decrease, forcing more water to run off the surface, picking up speed and pollutants.

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• The concentration of pollutants in the runoff. Certain activities, such as those from industrial sites, are large contributors of pollutant concentrations to the MS4.

The report also identified several activities causing stormwater pollution from urban areas, including practices of homeowners, businesses, and government agencies.

Studies conducted by the United States Geological Survey (USGS) through its National Water Quality Assessment (NAWQA) program confirm the link between urbanization and water quality impairments in urban watersheds due to contaminated stormwater runoff (USGS, 2001).

Furthermore, the water quality impacts of urbanization and urban stormwater discharges have been examined and described by many researchers and summarized by U.S. EPA in a 1997 publication titled “Urbanization and Streams: Studies of Hydrologic Impacts”. Urbanization causes changes in hydrology and increases pollutant loads which adversely impact water quality and impair the beneficial uses of receiving waters. Increases in population density and imperviousness result in changes to stream hydrology including:
• increased peak discharges compared to predevelopment levels; • increased volume of storm water runoff with each storm compared to predevelopment levels; • decreased travel time to reach receiving water;
• increased frequency and severity of floods;
• reduced stream flow during prolonged periods of dry weather due to reduced levels of infiltration;
• increased runoff velocity during storms due to a combination of effects of higher discharge peaks, rapid time of concentration, and smoother hydraulic surfaces from channelization; and
• decreased infiltration and diminished ground water recharge.

The 2016 National Water Quality Inventory (CWA Section 305(b) Report) showed that urban runoff/storm water discharges contribute to the impairment of 49,330 miles of streams, to the impairment of 759,483 acres of lakes, to the impairment of 316 miles of coastal shoreline, and to the impairment of 16,773 square miles of estuaries in the United States.

Permittees in Ventura County and Los Angeles County have conducted monitoring to, among other objectives:
• assess the overall health and trends in receiving water quality; • assess impacts of MS4 discharges on receiving waters; • identify sources of pollutants;
• assess compliance with receiving water limitations and water quality-based effluent limitations derived from TMDL waste load allocations; and • measure and improve the effectiveness of measures implemented to comply with their MS4 permits.

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Monitoring by Permittees in the Los Angeles Region indicates that concentrations of pathogen indicators (fecal coliform, total coliform, and enterococcus), heavy metals (such as Pb, Cu, Zn, Cd, As, Ni, Ag) and pesticides (such as diazinon, malathion, lindane, total chlordane) among others exceed water quality standards in receiving waters. Receiving water impacts studies found that stormwater discharges from urban watersheds exhibit toxicity attributable to heavy metals. Bioassessments of the benthic communities showed bioaccumulation of toxicants. Sediment analysis showed higher concentrations of pollutants, such as Pb and PAHs, in urban watersheds than in rural watersheds (2 to 4 times higher). In addition, toxicity of dry weather, non-stormwater flows was observed with the cause of toxicity undetermined. Other studies have documented concentrations of pollutants that exceed water quality standards in storm drains flowing to the ocean during dry weather, and adverse health impacts from swimming near flowing storm drains (LARWQCB, 2020; Haile et al., 1999).

Trash is also a serious and pervasive water quality problem in the Los Angeles Region and statewide. In 2015, during development of the Amendment to the Water Quality Control Plan for Ocean Waters of California (Ocean Plan) for Trash Provisions and Part 1 Trash Provisions of the Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries (collectively referred to as “the Trash Amendments”), the State Water Board conducted a comprehensive assessment of the impacts of trash on beneficial uses of surface waters throughout the state, including impacts to aquatic habitat and aquatic life, public health, contact and non-contact water recreation, commercial and sport fishing, navigation, and Native American culture.11 Trash in waterways causes significant water quality problems. Small and large floatables inhibit the growth of aquatic vegetation, decreasing habitat and spawning areas for fish and other living organisms. Wildlife living in rivers and in riparian areas can be harmed by ingesting or becoming entangled in floating trash. Except for large items, settleables are not always obvious to the eye. They include glass, cigarette butts, rubber, and construction debris, among other things. Settleables can be a problem for bottom feeders and can contribute to sediment contamination. Some debris (e.g., diapers, medical and household waste, and chemicals) are a source of bacteria and toxic substances. Floating debris that is not trapped and removed will eventually end up on the beaches or in the open ocean, keeping visitors away from our beaches and degrading coastal waters. Through periodic surface water quality assessments pursuant to Clean Water Act section 305(b) and identification of impaired waters pursuant to Clean Water Act section 303(d), the Los Angeles Water Board has determined that current levels of trash exceed the existing water quality objectives contained in the Basin Plan that are necessary to protect the beneficial uses of many surface waters. Los Angeles Water Board staff regularly observes trash in surface waters throughout the Los Angeles Region. Non-profit organizations such as Heal the Bay, Friends of the Los Angeles River (FoLAR) and others organize volunteer clean-ups periodically and document the amount of trash collected. Significant strides have been made by a number of Permittees in addressing this problem through the implementation of control measures to achieve waste load allocations established in trash TMDLs.

As discussed above, pollutants in stormwater and non-stormwater have damaging effects on both human health and aquatic ecosystems. Water quality assessments 11 State Water Resources Control Board. Amendment to the Water Quality Control Plan for the Ocean Waters of California to Control Trash and Part 1 Trash Provisions of the Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California: Final Staff Report Appendix A “Trash Background.”

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conducted by the Los Angeles Water Board have identified impairment of beneficial uses of water bodies in the Los Angeles Region caused or contributed by pollutants in MS4 discharges. As a result of these impairments, there are beach postings, fish consumption advisories, ecosystem and recreational impacts from trash and debris, and toxic conditions for aquatic life, among others. Forty-five TMDLs established by the Los Angeles Water Board and U.S. EPA identify MS4 discharges as one of the pollutant sources causing or contributing to the water quality impairments of the myriad waterbodies addressed by the TMDLs.

The Ventura County Permittees’ January 2015 Report of Waste Discharge identifies a number of pollutants of concern in Table 3-25, including indicator bacteria, trash, sedimentation/siltation, pesticides (diazinon, chlorpyrifos, dieldrin, chlordane, DDT compounds, toxaphene, and bifenthrin), minerals (boron, chloride, sulfate, TDS), PCBs, metals (copper, nickel, mercury, aluminum), selenium, nutrients and nutrient related effects (total nitrogen, total phosphorus, algal biomass, algal percent cover, dissolved oxygen), toxicity, and temperature among others. Ventura County Permittees’ Annual Reports (2009/2010 – 2018/2019) confirm these pollutants of concern, reporting E. coli, chloride, total dissolved solids (TDS), selenium and metals, including dissolved copper and total aluminum as some of the pollutants in MS4 discharges. Additionally, the Los Angeles Water Board has also identified nutrients, pesticides, heavy metals, and trash as pollutants of concern in various areas of Ventura County and, through TMDL development, has identified MS4 discharges as one of the sources of these pollutants.

An analysis of monitoring data relative to TMDL implementation in Ventura County is summarized below.

The Los Angeles Water Board, based on monitoring data collected during the term of Order No. R4-2012-0175 (2012/2013 – 2016/2017) has identified bacteria, nutrients, pesticides, metals, and trash among others as pollutants of concern in various areas of Los Angeles County and, through TMDL development, has identified MS4 discharges as one of the sources of these pollutants. An analysis of monitoring data analysis relative to TMDL implementation in Los Angeles County is also summarized below.

1. Mass Emission Stations
Permittees have historically monitored receiving waters throughout the Los Angeles Region at a set of receiving water monitoring stations referred to as “mass emission stations.” These stations were established to assess compliance with the Los Angeles County MS4 Permit and the Ventura County MS4 Permit. The mass emission stations are generally located at the base of watersheds and are intended to monitor the quality of water discharged from large mixed land use areas. Results from the mass emission monitoring are also used to estimate pollutant loads and to analyze long term water quality trends. Monitoring at these stations provides a high-level look at the impacts of MS4 discharges on receiving waters during storm events and during dry weather conditions.
a. Wet Weather Mass Emission Station Monitoring
The table below highlights the frequency that select constituents exceeded wet weather TMDL targets and/or Basin Plan water quality objectives at each mass emission station during the period of the permit terms for Order No. R4- 2010-0108 and Order No. R4-2012-0175 from 2009 to 2017. This table shows that bacteria and metals are not achieving objectives during storm events throughout the Los Angeles Region. E. coli exceeded TMDL targets and/or Basin Plan objectives in more than 25% of wet weather samples. Additionally,

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eight of ten stations had metals that exceeded TMDL targets and/or Basin Plan objectives in more than 25% of wet weather samples. Nutrients had exceedances in two of the ten stations.

Table F-4. Summary of Major Constituents Exceeding TMDL Targets and/or Basin Plan Water Quality Objectives at Mass Emission Stations During Wet Weather Conditions (2009-2017)
Mass Emission
Station Condition
1% - 10% of
Samples
Exceeded TMDL
Target/Basin
Plan Objective
11% - 25% of
Samples
Exceeded TMDL
Target/Basin
Plan Objective
> 25% of
Samples
Exceeded TMDL
Target/Basin
Plan Objective
Ballona Creek Wet - Total Lead E. coli, Total
Copper, Total Zinc
Calleguas Creek Wet - - E. coli
Coyote Creek Wet - -
E. coli, Total
Copper, Total Zinc
Dominguez
Channel Wet - Total Lead E. coli, Total Copper, Total Zinc Los Angeles
River Wet - Total Lead E. coli, Total Copper, Total Zinc Malibu Creek Wet - -
E. coli, Total
Nitrogen, Total
Phosphorus
San Gabriel River Wet - Total Zinc E. coli, Total
Copper
Santa Clara River
(Lower) Wet Nitrate + Nitrite -
E. coli, Total
Copper, Total Zinc
Santa Clara River
(Upper) Wet Total Lead Total Zinc E. coli, Total Copper Ventura River Wet - - E. coli
b. Dry Weather Mass Emission Station Monitoring
The table below similarly shows the frequency that the same set of constituents exceeded dry weather TMDL targets and/or Basin Plan water quality objectives at each mass emissions station. E. coli exceeded TMDL targets and/or Basin Plan objectives in six of ten stations. Metals exceeded targets and limitations in two of ten stations. Nutrients exceeded targets and limitations in two of ten stations.

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Table F-5. Summary of Major Constituents Exceeding TMDL Targets and/or Basin Plan Water Quality Objectives at Mass Emission Stations During Dry Weather Conditions (2009-2017)
Mass Emission
Station Condition
1% - 10% of
Samples
Exceeded TMDL
Target/Basin
Plan Objective
11% - 25% of
Samples
Exceeded TMDL
Target/Basin
Plan Objective
> 25% of
Samples
Exceeded TMDL
Target/Basin
Plan Objective
Ballona Creek Dry Total Copper,
Total Zinc E. coli -
Calleguas Creek Dry - E. coli -
Coyote Creek Dry - - E. coli
Dominguez
Channel Dry - Total Copper E. coli
Los Angeles
River Dry - - E. coli
Malibu Creek Dry - -
Total Nitrogen,
Total Phosphorus
San Gabriel River Dry - Nitrate + Nitrite -
Santa Clara River
(Lower) Dry - - -
Santa Clara River
(Upper) Dry - - -
Ventura River Dry - E. coli -

2. Bacteria
Indicator bacteria (e.g., E. coli, total coliform, fecal coliform, and Enterococcus) are monitored to indicate the likelihood of pathogens in surface waters. The Los Angeles Water Board’s Basin Plan establishes water quality objectives for indicator bacteria to protect water contact recreation (REC-1) and non-contact water recreation (REC-2) beneficial uses. Permittees have monitored bacteria to implement bacteria TMDLs in the Los Angeles Region and to implement beach water quality monitoring requirements under Health and Safety Code sections 115880, 115885, and 115915.
a. Wet Weather Bacteria Monitoring
The tables below summarize wet weather bacteria monitoring at receiving water and outfall monitoring stations. Data from 2012 to 2017 was analyzed for Los Angeles County. Data from 2009 through 2017 was analyzed for Ventura County. Indicator bacteria consistently exceeded water quality objectives at receiving water monitoring stations. In several watersheds, the frequency of samples exceeding objectives was more than 50%. Outfalls have also consistently exceeded applicable E. coli effluent limitations. In some watersheds, all outfalls samples exceeded effluent limitations.

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Table F-6. Summary of Wet Weather Bacteria Monitoring at Receiving Water Stations Watershed TMDL # of
Stations
# of
Exceedances
# of
Samples
%
Exceed
Ballona
Creek
Ballona Creek Bacteria
TMDL 8 155 203 76%
Dominguez
Channel
Los Angeles Harbor Bacteria
TMDL 3 164 385 43%
Los
Angeles
River
Los Angeles River Bacteria
TMDL 7 26 45 58%
Los
Angeles
River
Long Beach City Beaches
and Los Angeles River
Estuary Bacteria TMDL
12 175 330 53%
Malibu
Creek
Malibu Creek and Lagoon
Bacteria TMDL 14 127 198 64%
Marina del
Rey
Marina del Rey Harbor
Mothers’ Beach and Back
Basins Bacteria TMDL
13 367 733 50%
Misc.

Ventura
Coastal
Watersheds
Harbor Beaches of Ventura
County Bacteria TMDL 2 43 135 32%
San Gabriel
River
San Gabriel River Bacteria
TMDL 10 48 51 94%
Santa Clara
River
Santa Clara River Estuary
and Reaches 3, 5, 6, and 7
Indicator Bacteria TMDL
4 30 37 81%
Santa
Monica Bay
Santa Monica Bay Beaches
Bacteria TMDL 68 1174 3770 31%
Alamitos
Bay (non-TMDL areas) 4 82 149 55%
Calleguas
Creek (non-TMDL areas) 1 21 22 95%
Colorado
Lagoon (non-TMDL areas) 2 27 70 39%
Dominguez
Channel (non-TMDL areas) 2 19 19 100%
Los
Cerritos
Channel
(non-TMDL areas) 3 18 18 100%
Ventura
River (non-TMDL areas) 1 23 26 88%

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Table F-7. Summary of Wet Weather Bacteria Monitoring at Outfall Stations Watershed TMDL # of
Stations
# of
Exceedances
# of
Samples
%
Exceed
Ballona
Creek
Ballona Creek Bacteria
TMDL 2 9 9 100%
Los Angeles
River
Los Angeles River Bacteria
TMDL 12 17 37 46%
Malibu
Creek
Malibu Creek and Lagoon
Bacteria TMDL 3 6 6 100%
Marina del
Rey
Marina del Rey Harbor
Mothers’ Beach and Back
Basins Bacteria TMDL
1 3 3 100%
San Gabriel
River
San Gabriel River Bacteria
TMDL 12 53 58 91%
Santa Clara
River
Santa Clara River Estuary
and Reaches 3, 5, 6, and 7
Indicator Bacteria TMDL
11 91 103 88%
Alamitos
Bay (non-TMDL areas) 1 3 3 100%
Dominguez
Channel (non-TMDL areas) 4 9 9 100%
Los Cerritos
Channel (non-TMDL areas) 1 3 3 100%
b. Dry Weather Bacteria Monitoring
The tables below summarize dry weather bacteria monitoring at receiving water and outfall monitoring stations. Data from 2012 to 2017 was analyzed for Los Angeles County. Data from 2009 through 2017 was analyzed for Ventura County. Compared to wet weather, there were fewer exceedances of water quality objectives at receiving water stations. Outfalls consistently exceeded applicable E. coli effluent limitations.

Table F-8. Summary of Dry Weather Bacteria Monitoring at Receiving Water Stations Watershed Associated
TMDL
Weather
Condition
# of
Stations
# of
Exceedances
# of
Samples
%
Exceed
Ballona
Creek
Ballona Creek
Bacteria TMDL Dry 8 950 1763 54%
Dominguez
Channel
Los Angeles
Harbor Bacteria
TMDL
Dry
(Winter) 3 159 899 18%
Dominguez
Channel
Los Angeles
Harbor Bacteria
TMDL
Dry
(Summer) 3 269 1618 17%
Los
Angeles
River
Los Angeles
River Bacteria
TMDL
Dry 25 293 513 57%

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Watershed Associated
TMDL
Weather
Condition
# of
Stations
# of
Exceedances
# of
Samples
%
Exceed
Los
Angeles
River
Long Beach City
Beaches and
Los Angeles
River Estuary
Bacteria TMDL
Dry
(Winter) 12 59 796 7%
Los
Angeles
River
Long Beach City
Beaches and
Los Angeles
River Estuary
Bacteria TMDL
Dry
(Summer) 12 170 1507 11%
Malibu
Creek
Malibu Creek
and Lagoon
Bacteria TMDL
Dry 15 346 1447 24%
Marina del
Rey
Marina del Rey
Harbor Mothers’
Beach and Back
Basins Bacteria
TMDL
Dry
(Winter) 13 353 1479 24%
Marina del
Rey
Marina del Rey
Harbor Mothers’
Beach and Back
Basins Bacteria
TMDL
Dry
(Summer) 13 338 2722 12%
Misc.

Ventura
Coastal
Watersheds
Harbor Beaches
of Ventura
County Bacteria
TMDL
Dry
(Winter) 2 21 219 10%
Misc.

Ventura
Coastal
Watersheds
Harbor Beaches
of Ventura
County Bacteria
TMDL
Dry
(Summer) 2 26 469 6%
San Gabriel
River
San Gabriel
River Bacteria
TMDL
Dry 10 17 38 45%
Santa Clara
River
Santa Clara
River Estuary
and Reaches 3,
5, 6, and 7
Indicator
Bacteria TMDL
Dry 3 0 15 0%
Santa
Monica Bay
Santa Monica
Bay Beaches
Bacteria TMDL
Dry
(Winter) 68 938 7839 12%
Santa
Monica Bay
Santa Monica
Bay Beaches
Bacteria TMDL
Dry
(Summer) 68 746 14094 5%
Alamitos
Bay
(non-TMDL
areas) Dry 4 57 980 6%

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Watershed Associated
TMDL
Weather
Condition
# of
Stations
# of
Exceedances
# of
Samples
%
Exceed
Calleguas
Creek
(non-TMDL
areas) Dry 1 1 9 11%
Colorado
Lagoon
(non-TMDL
areas) Dry 2 14 475 3%
Dominguez
Channel
(non-TMDL
areas) Dry 2 7 12 58%
Los Cerritos
Channel
(non-TMDL
areas) Dry 1 2 3 67%
Ventura
River
(non-TMDL
areas) Dry 1 1 9 11%
Table F-9. Summary of Dry Weather Bacteria Monitoring at Outfall Stations Watershed Associated TMDL # of
Stations
# of
Exceedances
# of
Samples
%
Exceed
Malibu
Creek
Malibu Creek and Lagoon
Bacteria TMDL 1 1 1 100%
San
Gabriel
River
San Gabriel River Bacteria
TMDL 3 6 17 35%
Santa
Clara River
Santa Clara River Estuary
and Reaches 3, 5, 6, and 7
Indicator Bacteria TMDL
9 37 60 62%
Los
Cerritos
Channel
(non-TMDL areas) 1 1 1 100%

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3. Metals
Permittees have monitored metals at several receiving water and outfall monitoring stations. This reflects the number of metals TMDLs and metals impairments throughout the Los Angeles Region. Copper, lead, and zinc are the primary metals of concern in the region as concentrations of these metals have exceeded water quality objectives for protection of aquatic life, which are established in the California Toxics Rule (CTR). Zinc and copper have often been identified as “limiting pollutants” in Watershed Management Programs established under the Los Angeles County and City of Long Beach MS4 Permits.
a. Wet Weather Metals Monitoring
The tables below summarize Permittees’ wet weather metals monitoring in select watersheds during the previous permit term (2009-2017 in Ventura County and 2012-2017 in Los Angeles County). Copper and/or zinc exceedances were observed at many receiving water stations when monitoring results were compared to CTR acute criteria for both total metals and dissolved metals.

Where outfall monitoring was conducted, many outfalls exceeded applicable effluent limitations for copper and zinc during wet-weather monitoring.

Exceedances for these two constituents were observed at outfall stations in Calleguas Creek, Santa Clara River, Los Angeles River, Ballona Creek, San Gabriel River, and Los Cerritos Channel. Lead exceedances were also observed; however, these occurred at a far lower frequency.

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Table F-10. Summary of Wet Weather Metals Receiving Water Monitoring Exceeding Criteria by Watershed (Exceedances / Samples)
Parameter Ballona
Creek
Calleguas
Creek
Dominguez
Channel
Los
Angeles
River
Los Cerritos
Channel
San
Gabriel
River
Santa
Clara
River
Ventura
River
Cadmium
(Total) -- -- -- 3/48 -- -- -- --
Cadmium
(Dissolved) -- -- -- 0/42 -- -- -- --
Copper
(Total) 104/109 5/24 21/21 64/100 30/30 82/91 17/37 0/26 Copper
(Dissolved) 84/109 0/25 -- 19/94 30/30 34/91 -- --
Lead
(Total) 41/109 0/22 4/21 13/104 16/19 9/91 2/32 0/26
Lead
(Dissolved) 0/109 -- -- 1/98 6/19 0/91 -- --
Mercury
(Total) -- 7/27 -- -- -- -- -- --
Nickel
(Total) -- 0/24 -- -- -- -- -- --
Nickel
(Dissolved) -- 0/24 -- -- -- -- -- --
Selenium 0/80 -- -- -- -- 0/67 -- --
Zinc
(Total) 102/109 -- 21/21 83/102 19/19 74/93 10/37 0/26
Zinc
(Dissolved) -- 0/22 -- 20/96 17/19 20/93 -- --

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Table F-11. Summary of Wet Weather Metals Outfall Monitoring Exceeding Criteria by Watershed (Exceedances / Samples)
Parameter Ballona
Creek
Calleguas
Creek
Dominguez
Channel
Los Angeles
River
Los Cerritos
Channel
San
Gabriel
River
Santa
Clara
River
Ventura
River
Cadmium
(Total) -- -- -- 4/62 -- -- -- --
Copper
(Total) 8/9 26/43 0/6 27/65 -- 3/7 -- --
Lead
(Total) 2/9 -- 0/6 1/65 -- 0/38 -- --
Mercury
(Total) -- 8/26 -- -- -- -- -- --
Nickel
(Total) -- 0/43 -- -- -- -- -- --
Selenium 0/2 -- -- -- -- -- -- --
Zinc
(Total) 8/9 -- 0/6 39/62 -- 3/7 -- --

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b. Dry Weather Metals Monitoring
The tables below summarize Permittees’ dry weather metals monitoring in select watersheds during the previous permit term (2009-2017 in Ventura County and 2012-2017 in Los Angeles County). Compared to wet weather, there were fewer exceedances of dry weather effluent limitations at outfalls and receiving water limitations at receiving water stations. For several constituent and waterbodies, no exceedances were observed.

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Table F-12. Summary of Dry Weather Metals Receiving Water Monitoring Exceeding Criteria by Watershed (Exceedances / Samples)
Parameter Ballona
Creek
Calleguas
Creek
Dominguez
Channel
Los
Angeles
River
Los
Cerritos
Channel
San
Gabriel
River
Santa
Clara
River
Ventura
River
Cadmium
(Total) -- -- -- 0/18 -- -- -- --
Cadmium
(Dissolved) -- -- -- 0/14 -- -- -- --
Copper
(Total) 8/150 0/10 2/10 5/255 4/8 1/34 0/19 0/9
Copper
(Dissolved) 1/150 0/10 -- 2/251 4/8 0/34 -- --
Lead
(Total) 0/150 0/9 0/10 3/164 -- 0/31 0/16 0/9
Lead
(Dissolved) 0/150 -- -- 0/160 -- 0/31 -- --
Mercury
(Total) -- 0/11 -- -- -- -- -- --
Nickel
(Total) -- 0/10 -- -- -- -- -- --
Nickel
(Dissolved) -- 0/10 -- -- -- -- -- --
Selenium 0/78 0/10 -- -- -- 2/26 -- --
Zinc
(Total) 0/150 0/9 0/10 1/225 -- 0/35 0/19 0/9
Zinc
(Dissolved) 0/150 -- -- 0/221 -- 0/35 -- --

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Table F-13. Summary of Dry Weather Metals Outfall Monitoring Exceeding Criteria by Watershed (Exceedances / Samples)
Parameter Ballona
Creek
Calleguas
Creek
Dominguez
Channel
Los
Angeles
River
Los
Cerritos
Channel
San
Gabriel
River
Santa
Clara
River
Ventura
River
Cadmium
(Total) -- -- -- -- -- -- -- --
Copper
(Total) 1/8 9/17 -- 0/2 -- -- -- --
Lead
(Total) 0/8 -- -- 0/2 -- -- -- --
Mercury
(Total) -- 0/9 -- -- -- -- -- --
Nickel
(Total) -- 0/15 -- -- -- -- -- --
Selenium -- 0/8 -- -- -- 0/4 -- --
Zinc
(Total) 0/8 -- -- -- -- -- -- --

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4. Nutrients
Permittees have monitored nutrients at several receiving water and outfall monitoring stations in waterbodies with nutrient and nutrient-related impairments.

Data from 2012 to 2017 was analyzed for Los Angeles County. Data from 2009 through 2017 was analyzed for Ventura County. Although discharges from municipal wastewater treatment plants (also known as publicly owned treatment works or POTWs) have often been identified as major sources of impairments in some TMDLs, MS4 discharges have been identified as a source of impairment during wet weather and dry weather in several TMDLs. The tables below summarize nutrient monitoring at some select river systems with nutrient TMDLs.

Permittees also monitor nutrients in lake systems as there are several lakes in the Los Angeles Region that have nutrient TMDLs.

Table F-14. Summary of Nutrients Receiving Water Monitoring Exceeding Criteria by Watershed (Exceedances / Samples)
Limitation Calleguas
Creek
Los
Angeles
River
Malibu
Creek
(Summer)
Malibu
Creek
(Winter)
Santa
Clara River
Ammonia (1 Hr Avg) 0/546 0/57 -- -- 1/41
Ammonia (30 Day
Avg) 0/511 0/57 -- -- 1/35
Nitrate 176/546 1/65 -- -- 1/35
Nitrite 1/516 2/57 -- -- --
Nitrate + Nitrite 179/542 5/65 5/13 1/43 --
Total Phosphorus -- -- 12/14 -- --
Table F-15. Summary of Nutrients Outfall Monitoring Exceeding Criteria by Watershed (Exceedances / Samples)
Limitation Calleguas
Creek
Los
Angeles
River
Malibu
Creek
(Summer)
Malibu
Creek
(Winter)
Santa
Clara
River
Ammonia (1 Hr Avg) 0/108 0/28 -- -- 2/38
Ammonia (30 Day
Avg) 1/100 0/28 -- -- 2/28
Nitrate 0/1 0/21 -- -- --
Nitrite -- 2/21 -- -- --
Nitrate + Nitrite 1/109 1/28 2/2 0/6 0/28
Total Phosphorus -- -- 2/2 -- --

5. Salts
Permittees have monitored for salts at receiving water and outfall monitoring stations in waterbodies with salt impairments. Data from 2012 to 2017 was analyzed for Los Angeles County. Data from 2009 through 2017 was analyzed for Ventura County. The tables below summarize monitoring conducted for the Calleguas Creek Watershed Salts TMDL and Santa Clara River Chloride TMDL.

Both watersheds show continued exceedances of TMDL targets and/or receiving water limitations. The monitoring results for Santa Clara River is separated by the

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weather condition at sample collection. Dry weather receiving water and outfall samples exceeded more frequently than wet weather samples. For example, 12 of 19 (63%) dry weather outfall samples exceeded applicable limitations compared to 1 of 60 (2%) wet weather outfall samples.

Table F-16. Summary of Salts Monitoring at Receiving Water Stations Watershed Constituent Weather
Condition
# of
Stations
# of
Exceedances
# of
Samples
%
Exceed
Calleguas
Creek Boron -- 6 8 34 24%
Calleguas
Creek Chloride -- 6 4 44 9%
Calleguas
Creek Sulfate -- 6 8 36 22%
Calleguas
Creek TDS -- 6 8 44 18%
Santa Clara
River Chloride Wet 3 9 44 20%
Santa Clara
River Chloride Dry 3 12 20 60%
Table F-17. Summary of Salts Monitoring at Outfall Stations Watershed Constituent Weather
Condition
# of
Stations
# of
Exceedances
# of
Samples
%
Exceed
Calleguas Creek Chloride -- 4 10 24 42%
Calleguas Creek Sulfate -- 4 1 7 14%
Calleguas Creek TDS -- 4 7 24 29%
Santa Clara
River Chloride Wet 8 1 60 2%
Santa Clara
River Chloride Dry * 12 19 63%

6. Toxic Pollutants
Toxic pollutants include pesticides, PCBs, PAHs, and metals. Toxic pollutants can bioaccumulate in fish and other aquatic organisms, which is harmful for both the organisms as well as organisms that consume these species (including humans).

The Los Angeles Water Board’s Basin Plan establishes a narrative water quality objective to address bioaccumulation, which states “Toxic pollutants shall not be present at levels that will bioaccumulate in aquatic life to levels which are harmful to aquatic life or human health.” The State Water Board has established Sediment Quality Objectives for enclosed bays and estuaries, which state:
• Pollutants in sediments shall not be present in quantities that, alone or in combination are toxic to benthic communities in bays and estuaries of California; • Pollutants shall not be present in sediments at levels that will bioaccumulate in aquatic life to levels that are harmful to human health in bays and estuaries of California; and

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• Pollutants shall not be present in sediment at levels that alone or in combination are toxic to wildlife and resident finfish by direct exposure or bioaccumulate in aquatic life at levels that are harmful to wildlife or resident finfish by indirect exposure in bays and estuaries of California.

There are several TMDLs addressing impairments due to toxic pollutants in the Los Angeles Region. These TMDLs address impairments in estuaries, harbors, lakes, and other waterbodies where toxic pollutants can accumulate in the sediment.

Permittees have been monitoring toxic pollutants in several waterbodies throughout the Los Angeles Region. This monitoring includes sediment monitoring at estuaries, lakes, and bays; stormborne sediment during rain events; and fish tissue monitoring at receiving waters. Data from 2012 to 2017 was analyzed for Los Angeles County. Data from 2009 through 2017 was analyzed for Ventura County. The table below summarizes some of the toxic pollutant monitoring conducted by Permittees. Due to the complexity of toxics TMDLs, which often include interim limitations and the analysis of multiple lines of evidence, it should be noted that the information in the table is a simplification of receiving water conditions.

Table F-18. Summary of Toxic Pollutants Receiving Water Monitoring Exceeding Criteria by Watershed (Exceedances / Samples)
Parameter Sample
Type
Ballona
Estuary
Calleguas
Creek and
Mugu
Lagoon
Colorado
Lagoon
Dominguez
Channel
Estuary
Santa
Monica
Bay
4,4-DDD Sediment -- 0/66 -- -- --
4,4-DDE Sediment -- 0/66 -- -- --
4,4-DDT Sediment -- 1/66 -- -- --
Cadmium Stormborne
Sediment 2/13 -- -- -- --
Chlordane Fish Tissue -- -- 4/4 -- --
Chlordane Sediment -- 1/66 10/12 -- --
Chlordane Stormborne
Sediment 14/20 -- -- -- --
Copper Sediment -- -- -- 3/22 --
Copper Stormborne
Sediment 2/13 -- -- -- --
DDTs Fish Tissue -- -- -- 4/4 --
DDTs Sediment -- -- -- 3/22 3/3
DDTs Stormborne
Sediment 14/20 -- 11/12 -- --
Dieldrin Fish Tissue -- -- 2/4 -- --
Dieldrin Sediment -- 0/66 11/12 -- --
Lead Sediment -- -- 8/12 3/22 --
Lead Stormborne
Sediment 2/13 -- -- -- --
PAHs Fish Tissue -- -- 2/4 -- --

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Parameter Sample
Type
Ballona
Estuary
Calleguas
Creek and
Mugu
Lagoon
Colorado
Lagoon
Dominguez
Channel
Estuary
Santa
Monica
Bay
PAHs Sediment -- -- 0/12 1/22 --
PAHs Stormborne
Sediment 5/20 -- -- -- --
PCBs Fish Tissue -- -- 4/4 -- --
PCBs Sediment -- 0/66 7/12 2/22 3/3
PCBs Stormborne
Sediment 12/18 -- -- -- --
Silver Stormborne
Sediment 0/13 -- -- -- --
Toxaphene Sediment -- 0/66 -- -- --
Zinc Sediment -- -- 8/12 3/22
Zinc Stormborne
Sediment 2/13 -- -- -- --
F. History of the Previous Permits
Prior to the issuance of the Order, the Los Angeles Water Board issued Permittees in Ventura County, Permittees within the coastal watersheds of Los Angeles County (with the exception of the City of Long Beach), and the City of Long Beach their own respective Phase I MS4 Permits.

Ventura County MS4 Permit
The first MS4 Permit for Ventura County and the incorporated areas therein was Order No. 94-082, issued by the Los Angeles Water Board on August 22, 1994. Between 1994 and 2010, several iterations of this permit were issued. Order No. 94-082 was superseded by Order No. 00-108, issued by the Los Angeles Water Board on July 27, 2000. On May 7, 2009, the Los Angeles Water Board issued Order No. 09-0057, which superseded Order No. 00-108. On July 8, 2010, the Los Angeles Water Board issued Order No. R4-2010-0108, which superseded Order No. 09-0057, to address perceived procedural issues raised by the Building Industry Legal Defense Foundation and others in a petition to the State Water Board.

Prior to the issuance of the Order, Order No. R4-2010-0108 served as the NPDES permit for MS4 stormwater and non-stormwater discharges within the watersheds of Ventura County. The requirements of Order No. R4-2010-0108 applied to the Ventura County Watershed Protection District, County of Ventura, and the cities of Camarillo, Fillmore, Moorpark, Ojai, Oxnard, Port Hueneme, San Buenaventura (Ventura), Santa Paula, Simi Valley, and Thousand Oaks.

Working together under the Ventura County MS4 Permit, the VCWPD joined together with the County of Ventura and 10 incorporated cities to form the Ventura Countywide Stormwater Quality Management Program. VCWPD was designated as the Principal Permittee. The Principal Permittee coordinated and facilitated activities necessary to comply with the requirements of Order No. R4-2010-0108 but was not responsible for ensuring compliance of any of the other Permittees. As noted earlier, the designation of

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a Principal Permittee has not been carried over from Order No. R4-2010-0108 to the Order.

Los Angeles County MS4 Permit
The first MS4 permit for Los Angeles County and the incorporated areas therein was Order No. 90-079, issued by the Los Angeles Water Board on June 18, 1990. Order No. 96-054 was issued by the Los Angeles Water Board on July 15, 1996, which superseded Order No. 90-079. Order No. 96-054 was superseded by Order No. 01-182, which was issued by the Los Angeles Water Board on December 13, 2001. Order No. 01-182 was amended on September 14, 2006 by Order No. R4-2006-0074, on August 9, 2007 by Order No. R4-2007-0042, on December 10, 2009 by Order No. R4-2009-0130, and on October 19, 2010 and April 14, 2011 pursuant to a peremptory writ of mandate in Los Angeles County Superior Court Case No. BS122724. As discussed below, Order No. 01-182 did not regulate MS4 discharges originating from the City of Long Beach.

On November 8, 2012, the Los Angeles Water Board issued Order No. R4-2012-0175, which superseded Order No. 01-182, as amended. Thereafter, several Los Angeles County MS4 Permittees and environmental organizations filed 37 petitions with the State Water Board challenging various provisions of Order No. R4-2012-0175. On June 16, 2015, the State Water Board adopted Order WQ 2015-0075, which generally upheld Order No. R4-2012-0175 but with a number of revisions to the findings and provisions.

Two cities and two environmental organizations subsequently filed three lawsuits (petitions for writ of mandate) against the Los Angeles Water Board and State Water Board challenging various aspects of Los Angeles Water Board Order No. R4-2012- 0175 and State Water Board Order WQ 2015-0075. These lawsuits have the following brief background and status:
• Natural Resources Defense Council (NRDC) and Los Angeles Waterkeeper’s primary contention is that allowing permittees to implement approved watershed management programs (WMPs) in lieu of strictly complying with receiving water limitations violates federal NPDES anti-backsliding requirements and state and federal anti-degradation requirements. In January 2017, the Los Angeles County Superior Court denied the petition for writ of mandate and upheld Order No. R4- 2012-0175. Upon appeal by NRDC and Los Angeles Waterkeeper, on December 24, 2018, the Second District Court of Appeal issued an unpublished, mixed decision.
12 On the anti-backsliding claim, the Court of Appeal affirmed the conclusions of the State Water Board and the trial court that the anti-backsliding provisions did not apply when the 2012 permit authorized WMPs as an alternative means of compliance with receiving water limitations. As for the anti-degradation claim, the Court of Appeal reversed and remanded the trial court’s anti-degradation ruling on procedural grounds. The Court of Appeal held that the trial court applied the wrong standard of review, but did affirm that a simple anti-degradation analysis applied to the permit. On remand, the Superior Court ruled that the Water Boards’ anti-degradation analysis in Order No. R4-2012-0175 pertaining to high quality waters only was not supported by adequate findings and issued a judgment on April 21, 2021, stating that the court will issue a writ of mandate ordering the Water Boards to set aside Order No. R4-2012-0175. Following issuance of the writ, the Los Angeles Water Board will have 180 days to comply with the court’s writ.

Alternatively, if the Water Boards file a notice of appeal, they may also file a petition 12 Natural Res. Defense Council Inc. et al. v. State Water Res. Control Board et al. (Dec. 24, 2018) Cal.

Court of Appeal, Second Appellate District, Div. Five, Case No. B282016 [nonpub. opn.].

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for writ of supersedeas with the Court of Appeal to seek to keep the 2012 permit in effect pending appeal. Unless and until the Los Angeles Water Board supersedes the 2012 permit through issuance of this Order or otherwise acts to set aside the 2012 permit, the 2012 permit remains in effect.
13 • In two separate but related cases, the cities of Duarte and Gardena challenged various aspects of Order No. R4-2012-0175, including alleging that the Los Angeles Water Board failed to properly consider economic considerations under Water Code section 13241 before imposing numeric effluent limitations (NELs). In September 2019, the Orange County Superior Court issued writs of mandate in both cases requiring the Los Angeles Water Board to set aside all NELs in the 2012 permit and to reconsider the permit in light of the court’s ruling. The court ruled that the Water Boards were required to consider costs under Water Code section 13241, as it had determined that incorporation of NELs in the 2012 permit exceeded federal Clean Water Act requirements, and that the Water Boards failed to adequately do so. The court declined to address the cities’ other contentions as it found the NEL issue dispositive. The Water Boards disagreed with the court’s ruling and appealed the decision. On January 28, 2021, the Court of Appeal issued a unanimous, published decision in the City of Duarte case and a companion unpublished decision in the City of Gardena case reversing the trial court’s rulings in both cases. The Court of Appeal did not decide whether NELs were more stringent than required by federal law. Assuming without deciding that they were more stringent and required considering of the Water Code section 13241 factors, the Court of Appeal concluded that “The Regional Board developed an economic analysis of the Permit’s requirements, consistent with Water Code section 13241.” (City of Duarte v. State Water Resources Control Board et al. (2021) 60 Cal.App.5th 258, as modified on denial of rehearing (Feb. 19, 2021); City of Gardena v. State Water Resources Control Board et al. (2021) Cal. Court of Appeal, Fourth Appellate Dist., Div. Three, Case No. G058540, as modified on denial of rehearing (Feb 19, 2021) [nonpub. opn.].) On April 28, 2021, the California Supreme Court denied the cities’ Petitions for Review, leaving the appellate court’s rulings in place. The Court of Appeal has directed the trial court to deny the cities’ petitions for writ of mandate and to enter judgments in favor of the Water Boards.

The Los Angeles Water Board further amended Order No. R4-2012-0175 on September 8, 2016 (Order No. R4-2012-0175-A01) incorporating provisions consistent with the revised Ballona Creek Watershed Trash TMDL and the revised Los Angeles River Watershed Trash TMDL. Additionally, on July 9, 2018, the Los Angeles Water Board Executive Officer modified Table E-2 of Attachment E (Monitoring and Reporting Program) to Order No. R4-2012-0175 to remove fecal coliform from the freshwater monitoring requirements.

Prior to the issuance of the Order, Order No. R4-2012-0175, as amended, served as the NPDES permit for MS4 stormwater and non-stormwater discharges within the coastal watersheds of Los Angeles County. The requirements of Order No. R4-2012- 0175 applied to the Los Angeles County Flood Control District, the unincorporated areas of Los Angeles County under Los Angeles County’s jurisdiction, and 84 cities within the coastal watersheds of Los Angeles County except for the City of Long Beach. 13 Natural Res. Defense Council, Inc. et al. v. State Wat. Res. Control Bd. et al., Los Angeles County Superior Court, Case No. BS156962 (March 29, 2021). Judge Beckloff’s ruling did not change the Court of Appeals’ anti-backsliding analysis.

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City of Long Beach MS4 Permit
The Los Angeles Water Board regulated discharges from the City of Long Beach’s MS4 from 1990 through 1999 under the Los Angeles countywide MS4 requirements contained in Order No. 90-079 and Order No. 96-054 issued on June 18, 1990 and July 15, 1996, respectively.

In 1999, the Los Angeles Water Board issued a separate MS4 Permit, Order No. 99- 060, to the City of Long Beach for discharges originating from its MS4. Order No. 99- 060 was superseded by Order No. R4-2014-0024, which was issued by the Los Angeles Water Board on February 6, 2014. The Los Angeles Water Board amended Order No.

R4-2014-0024 on September 8, 2016 (Order No. R4-2014-0024-A01) incorporating provisions consistent with the revised Los Angeles River Watershed Trash TMDL.

Additionally, on July 9, 2018, the Los Angeles Water Board Executive Officer modified Table E-2 of Attachment E (Monitoring and Reporting Program) to Order No. R4-2014- 0024 to remove fecal coliform from freshwater monitoring requirements.

Order No. R4-2014-0024, as amended, served as the NPDES permit for MS4 stormwater and non-stormwater discharges for the City of Long Beach prior to the issuance of the Order.

Regional MS4 Permit
Except for enforcement purposes, the Order supersedes the previous orders for Permittees in Ventura County, Permittees within the coastal watersheds of Los Angeles County (excepting the City of Long Beach), and the City of Long Beach to cover all Phase I MS4 Permittees within the coastal watersheds of the Los Angeles Region with one regionwide Phase I MS4 Permit (Regional MS4 Permit).

G. Summary of Requirements in Previous Permits
Ventura County
The Ventura County MS4 Permit was last reissued in 2010 as Order No. R4-2010-0108.

Order No. R4-2010-0108 expired on July 8, 2015, but was administratively continued pursuant to federal and state regulations. Order No. R4-2010-0108 was organized under the following seven parts and included several attachments. The description below briefly summarizes key permit parts and attachments in Order No. R4-2010-0108.

Part 1 – Discharge Prohibitions
As required by section 402(p)(3)(B)(ii) of the Clean Water Act, Part 1 requires permittees to effectively prohibit non-stormwater discharges into the MS4 and receiving waters, except where such discharges: originate from a State, Federal, or other source for which they are pre-empted from regulating by State or federal law; are covered by a separate NPDES permit or conditional waiver of waste discharge requirements (WDRs) for irrigated lands; are flows from firefighting activities; or fall within one of thirteen categories of flows that are conditionally exempted from the discharge prohibition. These exempted flows fall under certain categories of natural flows and flows incidental to urban activities (i.e., landscape irrigation, sidewalk rinsing). These non-stormwater flows may be exempted so long as they are not a source of pollutants that exceed water quality standards and permittees meet all conditions where specified.

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Part 2 – Receiving Water Limitations
Pursuant to State Water Board Order WQ 99-05, Part 2 prohibits discharges from the MS4 that cause or contribute to a violation of water quality standards. In addition, discharges from the MS4 of stormwater or non-stormwater, for which a Permittee is responsible, may not cause or contribute to a condition of nuisance.

Part 2.3 requires permittees to comply with receiving water limitations through timely implementation of control measures and other actions to reduce pollutants in the stormwater discharges. If exceedances persist, the Permittee shall ensure compliance with receiving water limitations by following a list of procedures such as submitting a report to the Los Angeles Water Board Executive Officer that describes what additional BMPs are being implemented to address the exceedances. Part 2.4 requires Permittees to annually report the effectiveness of BMPs in reducing exceedances of receiving water limitations.

Part 3 – Stormwater Quality Management Program (SQMP) Implementation Under Part 3, each Permittee shall, at a minimum, adopt and implement applicable terms of the permit within its jurisdictional boundary. As Principal Permittee, VCWPD shall be responsible for program coordination as described in the permit, as well as compliance with applicable portions of the permit within its jurisdiction.

Each Permittee shall also comply with the requirements of 40 CFR section 122.26(d)(2) and implement programs and control measures so as to reduce the discharges of pollutants in stormwater to the maximum extent practicable (MEP) and achieve water quality standards. Part 3 also requires each Permittee to achieve treatment BMP performance standards identified in Attachment C for an 85th percentile 24-hour runoff event.

With regards to TMDLs, Part 3 requires each Permittee to implement programs and measures to comply with TMDL WLAs assigned to MS4 discharges as specified in Part 5. The WLAs are expressed numerically in Part 5 as water quality-based effluent limitations and Permittees are expected to attain the WLAs by implementing BMPs. Additionally, permittees are required to submit an Annual Budget Summary that provides the estimated expenditures to implement the permit for the upcoming report year.

Part 3 also sets forth specific responsibilities of the Principal Permittee and other Permittees such as participation in committee meetings and intra-agency coordination and requirements regarding each Permittee’s legal authority.

Part 4 – Special Provisions
Part 4 sets forth provisions for watershed initiative participation, public information and participation program, industrial/commercial facilities control program, planning and land development program, development construction program, public agency activities program, and illicit connections and illicit discharges elimination program. These programs are termed “minimum control measures” and have been in place since the inception of the MS4 NPDES permitting program, as required by federal regulations.

As part of general requirements, Part 4 allows Permittees to propose site-specific Best Management Practice (BMP) Substitution for Los Angeles Water Board Executive Officer approval. Part 4 also sets forth requirements for the Reporting Program in Attachment I.

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Part 5 – Total Maximum Daily Load (TMDL) Provisions
As required by 40 CFR section 122.44(d)(1)(vii)(B), the permit incorporated TMDL WLAs, expressed numerically in a manner consistent with the assumptions and requirements of the TMDL from which they were derived. In permit terms, these TMDL WLAs are water quality-based effluent limits. Part 5 requires permittees to comply with applicable WLAs and lists 13 TMDLs applicable to MS4 discharges within Ventura County with the WLAs assigned to MS4 discharges and compliance options.

Part 6 – Definitions
Part 6 includes definitions for terms used within the permit.

Part 7 – Standard Provisions
Part 7 includes standard provisions relating to implementation of the programs required by the permit. Such provisions include, but are not limited to, the duty to comply, the duty to mitigate, inspection and entry requirements, proper operation and maintenance requirements, monitoring and reporting requirements, and the duty to provide information. Most of these provisions are required by 40 CFR sections 122.41 or 122.42 and apply to all NPDES permits.

Attachment A – Watershed Management Areas
Attachment A includes a table that lists the Watershed Management Areas and their respective major surface waterbodies, hydrologic units, Clean Water Act section 303(d) listed pollutants, and permittees.

Attachment B – Pollutants of Concern for Calleguas Creek, Santa Clara River, and Ventura River Watersheds
Attachment B includes pollutants of concern for Calleguas Creek, Santa Clara River, and Ventura River Watershed based on 2003-2007 data from mass emissions stations, receiving water sites, and land use monitoring sites.

Attachment C – Treatment BMP Performance Standards and Effluent Concentrations as Median Values
Attachment C provides treatment BMP performance standards which includes a table of parameters and their respective effluent concentrations for various categories of BMPs.

Attachment D – Critical Sources Categories
Attachment D lists facilities and their Standard Industrial Classification (SIC) codes for critical sources.

Attachment E – Determination of Erosion Potential
Attachment E includes formulas to determine erosion potential.

Attachment F – Monitoring Program
Attachment F has self-monitoring requirements, which include: (1) monitoring of “mass emissions” at three mass emission monitoring stations; (2) monitoring of major outfalls specified in Attachment I; (3) Dry Weather Analytical Monitoring; (4) Aquatic Toxicity Monitoring; (5) Beach Water Quality Monitoring; (6) TMDL Monitoring; (7) Bioassessment; and (8) Special Studies.

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Attachment G – Storm Water Monitoring Program’s Constituents and Associated Minimum Levels
Attachment G includes a table listing the required stormwater monitoring program constituents and their associated minimum levels.

Attachment H – Storm Water Monitoring Program’s Major Outfall Stations Attachment H includes a table listing the required major outfall monitoring sites and the responsible permittees.

Attachment I – Reporting Program Requirements
Attachment I has reporting requirements where an annual report includes: (1) monitoring of “mass emissions” at three mass emission monitoring stations; (2) monitoring of major outfalls specified in Attachment H; (3) Dry Weather Analytical Monitoring; (4) Aquatic Toxicity Monitoring; (5) Beach Water Quality Monitoring; (6) TMDL Monitoring; (7) Bioassessment; and (8) Special Studies. Permittees are also required to submit an Annual Monitoring Program Report, which answers a set of questions on discharge prohibitions and receiving water limitations. Additionally, Permittees are required to include in their Annual Report answers to a set of questions on the SQMP and special provisions of the Order.

Fact Sheet/Staff Report
The Fact Sheet/Staff Report provides an overview of the Ventura County MS4 Permit and explains the significant factual, legal, methodological, technical, and policy rationale that serve as the basis for the permit requirements.

Los Angeles County
The Los Angeles County MS4 Permit was last reissued in 2012 as Order No. R4-2012- 0175 and was amended as described above. Order No. R4-2012-0175 expired on December 28, 2017 but was administratively continued pursuant to federal and state regulations. Order No. R4-2012-0175 is organized under six parts and includes several attachments. The description below summarizes key permit parts and attachments in Order No. R4-2012-0175.

Part III. Discharge Prohibitions
As required by section 402(p)(3)(B)(ii) of the Clean Water Act, Part III requires Permittees to prohibit non-stormwater discharges through the MS4 to receiving waters except for non-stormwater discharges regulated under a separate NPDES permit, temporary non-stormwater discharges authorized by U.S. EPA, authorized non-stormwater discharges from emergency firefighting activities, natural flows, and certain conditionally exempt discharges.

Part IV. Effluent Limitations and Discharge Specifications Part IV requires each Permittee to comply with technology based effluent limitations by reducing pollutants in stormwater discharges from the MS4 to the maximum extent practicable (MEP). Part IV also requires Permittees to comply with applicable water quality-based effluent limitations (WQBELs) as set forth in Part VI.E of the permit.

Part V. Receiving Water Limitations
Pursuant to State Water Board Order WQ 99-05, Part V prohibits discharges from the MS4 that cause or contribute to a violation of receiving water limitations. In

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addition, discharges from the MS4 of stormwater or non-stormwater, for which a Permittee is responsible, shall not cause or contribute to a condition of nuisance.

Part V.3 requires permittees to comply with receiving water limitations through timely implementation of control measures and other actions to reduce pollutants in the discharges. If exceedances persist, the Permittee shall ensure compliance with receiving water limitations by following a list of procedures, such as submitting an Integrated Monitoring Compliance Report to the Los Angeles Water Board Executive Officer that describes what additional BMPs are being implemented to address the exceedances.

Part VI. Provisions
Part VI includes requirements for standard provisions, monitoring and reporting, watershed management programs, stormwater management program minimum control measures (MCMs), and Total Maximum Daily Loads (TMDLs).

Standard provisions include requirements to comply with Attachment D, ensure each Permittee has the necessary legal authority to prohibit non-stormwater discharges through the MS4 to receiving waters, as well as possess adequate legal authority to develop and enforce stormwater and non-stormwater ordinances for its jurisdiction. It also lists responsibilities of Permittees and requires Permittees to conduct a fiscal analysis and report it in their annual report. There are also provisions for public review and Los Angeles Water Board review, permit reopener and modification provisions, and enforcement provisions including enforcement of water quality-based effluent limitations for trash.

The monitoring and reporting provisions require compliance with Attachment E (Monitoring and Reporting Program) and also describe compliance determination for commingled discharges.

The watershed management program provisions in Part VI.C describe a voluntary alternative compliance pathway allowing permittees to individually or collaboratively develop a Watershed Management Program (WMP) or an Enhanced Watershed Management Program (EWMP). The WMP or EWMP allows Permittee(s) the flexibility to customize strategies, control measures, and BMPs to meet the requirements of the permit. Part VI.C describes compliance determination for participation in a WMP or EWMP, timelines for WMP or EWMP development and implementation, requirements to conduct a Reasonable Assurance Analysis (RAA), and provisions for an adaptive management process.

Part VI.D includes general requirements, progressive enforcement and interagency coordination provisions, and six MCMs that are the Public Information and Participation Program (PIPP), Industrial/Commercial Facilities Program, Planning and Land Development Program, Development Construction Program, Public Agency Activities Program, and Illicit Connections and Illicit Discharges Elimination Program (IC/IDE). Part VI.D.4 lists MCM provisions applicable to LACFCD.

Part VI.E includes TMDL provisions including compliance with applicable WQBELs and/or receiving water limitations contained in Attachments L through R, compliance determination for TMDLs, timelines for compliance with U.S. EPA TMDLs, and provisions for compliance with trash TMDLs.

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Attachment A – Definitions
Attachment A includes acronyms, abbreviations, and definitions for terms used within the permit.

Attachment B – Watershed Management Area Maps
Attachment B depicts each Watershed Management Area, its subwatersheds, and the major receiving waters.

Attachment C – MS4 Maps by Watershed Management Area
Attachment C depicts the major drainage infrastructure with the area covered under the permit by WMAs.

Attachment D – Standard Provisions
Attachment D includes standard provisions relating to implementation of the programs required by the permit. Such provisions include, but are not limited to, the duty to comply, the duty to mitigate, inspection and entry requirements, proper operation and maintenance requirements, monitoring and reporting requirements, and the duty to provide information. Most of these provisions are required by 40 CFR section 122.41, which applies to all NPDES permits, or section 122.42, which sets forth additional conditions applicable to specified categories of NPDES permits, including MS4 permits.

Attachment E – Monitoring and Reporting Program
Attachment E establishes monitoring, reporting, and recordkeeping requirements.

Attachment E allows for an integrated monitoring approach where a Permittee can submit an Integrated Monitoring Program (IMP) or a group of Permittees can coordinate monitoring efforts on a watershed or subwatershed basis to submit a Coordinated Integrated Monitoring Program (CIMP) for Los Angeles Water Board Executive Officer approval. The IMP or CIMP must contain the following elements:
(1) receiving water monitoring; (2) stormwater outfall-based monitoring; (3) nonstormwater outfall-based monitoring; (4) new-development/re-development effectiveness tracking; and (5) regional studies. Furthermore, Attachment E specifies monitoring data and annual report submittal timelines and describes key elements to report on.

Attachment F – Fact Sheet
The Fact Sheet provides an overview of the Los Angeles County MS4 Permit and explains the significant factual, legal, methodological, technical, and policy rationale that serve as the basis for the requirements of the permit.

Attachment G – Non-Storm Water Action Levels and Municipal Action Levels Corresponding to Part III (Discharge Prohibitions) of the permit and non-stormwater outfall monitoring per Attachment E, Attachment G lists non-stormwater action levels for waterbodies. Additionally, Attachment G lists hardness-based action levels for metals. Municipal Action Levels listed in Attachment G apply to stormwater outfall monitoring conducted per Attachment E.

Attachment H – Bioretention/Biofiltration Design Criteria Corresponding to the Planning and Land Development MCM in the permit, Attachment H describes design specification requirements for bioretention and biofiltration systems.

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Attachment I – Developer Technical Information and Guidelines Attachment I requires Permittees to make available certain reference information and recommended guidelines to the development community. This information may include but is not limited to hydromodification control criteria, low impact development (LID) principles and specifications, and construction BMPs.

Attachment J – Determination of Erosion Potential
Corresponding to the Planning and Land Development MCM in the permit, Attachment J defines erosion potential and provides equations to calculate erosion potential.

Attachment K – Permittees and TMDLs Matrix
Attachment K provides a comprehensive list of TMDLs by Watershed Management Area and the Permittees subject to each TMDL.

Attachment L – TMDL Provisions for the Santa Clara River Watershed Management Area
Attachment L specifies four TMDLs incorporated in the permit with their WQBELs and/or receiving water limitations and compliance options.

Attachment M – TMDL Provisions for Santa Monica Bay Watershed Management Area (including Malibu Creek, Ballona Creek, and Marina del Rey Subwatersheds) Attachment M specifies 13 TMDLs incorporated in the permit with their WQBELs and/or receiving water limitations and compliance options.

Attachment N – TMDL Provisions for Dominguez Channel and Greater Harbor Waters Watershed Management Area (including Machado Lake Subwatershed) Attachment N specifies five TMDLs incorporated in the permit with their WQBELs and/or receiving water limitations and compliance options.

Attachment O – TMDL Provisions for Los Angeles River Watershed Management Area
Attachment O specifies seven TMDLs incorporated in the permit with their WQBELs and/or receiving water limitations and compliance options.

Attachment P – TMDL Provisions for the San Gabriel River Watershed Management Area
Attachment P specifies two TMDLs incorporated in the permit with their WQBELs and/or receiving water limitations and compliance options.

Attachment Q – TMDL Provisions for Los Cerritos Channel and Alamitos Bay Watershed Management Area
Attachment Q specifies two TMDLs incorporated in the permit with their WQBELs and/or receiving water limitations and compliance options.

Attachment R – TMDL Provisions for Middle Santa Ana River Watershed Management Area
Attachment R specifies one TMDL incorporated in the permit with its WQBELs and/or receiving water limitations and compliance options.

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City of Long Beach
The City of Long Beach MS4 Permit was last reissued in 2014 as Order No. R4-2014- 0024 and was amended as described above. Order No. R4-2014-0024 expired on March 28, 2019 but was administratively continued pursuant to federal and state regulations. Order No. R4-2014-0024 is organized under the following eight parts and includes several attachments. The description below summarizes key permit parts and attachments in Order No. R4-2014-0024.

Part III. Discharger Responsibilities
Part III requires the City of Long Beach to comply with provisions in the permit including attachments. It also requires the City of Long Beach to submit complete and timely reports and participate in intra-agency coordination.

Part IV. Discharge Prohibitions
Part IV requires the City of Long Beach to prohibit any discharge of toxic substances from the MS4 into surface waters in concentrations acutely or chronically toxic to animal or plant life. As required by section 402(p)(3)(B)(ii) of the Clean Water Act, Part IV also prohibits non-stormwater discharges through the MS4 to receiving waters except for non-stormwater discharges regulated under an NPDES permit, temporary non-stormwater discharges authorized by U.S. EPA, authorized non-stormwater discharges from emergency firefighting activities, natural flows, and certain conditionally exempt discharges.

Part V. Effluent Limitations and Discharge Specifications Part V requires the City of Long Beach to comply with technology based effluent limitations by reducing pollutants in stormwater discharges from the MS4 to the maximum extent practicable (MEP). Part V also requires the City of Long Beach to comply with WQBELs as set forth in Part VIII of the permit.

Part VI. Receiving Water Limitations
Pursuant to State Water Board Order WQ 99-05, Part VI prohibits discharges from the MS4 that cause or contribute to a violation of receiving water limitations. In addition, discharges from the MS4 of stormwater or non-stormwater, for which the City of Long Beach is responsible, shall not cause or contribute to a condition of nuisance. Part VI.3 requires the City of Long Beach to comply with receiving water limitations through timely implementation of control measures and other actions to reduce pollutants in the discharges. If exceedances persist, the City of Long Beach shall ensure compliance with receiving water limitations by following a list of procedures such as submitting an Integrated Monitoring Compliance Report to the Los Angeles Water Board Executive Officer that describes what additional BMPs are being implemented to address the exceedances.

Part VII. Provisions
Part VII includes standard provisions, monitoring and reporting requirements, provisions for watershed management programs, and stormwater management program MCMs such as PIPP, Industrial/Commercial Facilities Program, Planning and Land Development Program, Construction Program, Public Agency Activities Program, and IC/IDE Program. Monitoring and reporting provisions require compliance with Attachment E.

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Standard provisions include requirements to comply with Attachment D to ensure that the City of Long Beach has the necessary legal authority to prohibit nonstormwater discharges through the MS4, as well as possess adequate legal authority to develop and enforce stormwater and non-stormwater ordinances for its jurisdiction. It also requires the City of Long Beach to conduct a fiscal analysis and discuss it in their annual report. Other provisions include public review and Los Angeles Water Board review provisions, permit reopener and modification provisions, and enforcement provisions including enforcement of trash water quality-based effluent limitations.

The watershed management program provisions in Part VII.C describe a voluntary alternative compliance pathway allowing the City of Long Beach to individually or collaboratively with other MS4 Permittees develop a Watershed Management Program (WMP) or an Enhanced Watershed Management Program (EWMP). The WMP or EWMP allows the City of Long Beach flexibility to customize strategies, control measures, and BMPs to meet the requirements of the permit. It describes compliance determination for participation in a WMP or EWMP, timelines for WMP or EWMP development and implementation, requirements to conduct a Reasonable Assurance Analysis (RAA), and provisions for an adaptive management process.

Part VIII. Total Maximum Daily Loads
Part VIII lists TMDL provisions including compliance determination for TMDLs, timelines for compliance with U.S. EPA TMDLs, and provisions for compliance with trash TMDLs. It also requires the City of Long Beach to comply with applicable WQBELs to implement 9 TMDLs.

Attachment A – Definitions
Attachment A includes acronyms, abbreviations, and definitions for terms used within the permit.

Attachment B – Watershed Management Areas within the City of Long Beach Attachment B depicts the four WMAs within the City of Long Beach.

Attachment C – City of Long Beach MS4
Attachment C depicts the MS4 within the City of Long Beach.

Attachment D – Standard Provisions
Attachment D includes standard provisions relating to implementation of the programs required by the permit. Such provisions include, but are not limited to, the duty to comply, the duty to mitigate, inspection and entry requirements, proper operation and maintenance requirements, monitoring and reporting requirements, and the duty to provide information. Most of these provisions are required by 40 CFR section 122.41, which applies to all NPDES permits, and section 122.42, which sets forth additional conditions applicable to specified categories of NPDES permits, including MS4 permits.

Attachment F – Fact Sheet
The Fact Sheet provides an overview of the City of Long Beach MS4 Permit and explains the significant factual, legal, methodological, technical, and policy rationale that serve as the basis for the requirements of the permit.

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Attachment E – Monitoring and Reporting Program
Attachment E establishes monitoring, reporting, and recordkeeping requirements.

Attachment E allows for an integrated monitoring approach where the City of Long Beach can submit an Integrated Monitoring Program (IMP) or the City of Long Beach with other MS4 Permittees can coordinate monitoring efforts on a watershed or subwatershed basis to submit a Coordinated Integrated Monitoring Program (CIMP) for Los Angeles Water Board Executive Officer approval. The IMP or CIMP must contain the following elements: (1) receiving water monitoring; (2) stormwater outfall-based monitoring; (3) non-stormwater outfall-based monitoring; (4) newdevelopment/re-development effectiveness tracking; and (5) regional studies.

Furthermore, Attachment E specifies monitoring data and annual report submittal timelines and describes key elements to report on.

Attachment G – Non-Storm Water Action Levels and Municipal Action Levels Corresponding to Part IV (Discharge Prohibitions) of the permit and nonstormwater outfall monitoring per Attachment E, Attachment G lists non-stormwater action levels for waterbodies. Additionally, Attachment G lists hardness-based action levels for metals. Municipal Action Levels listed in Attachment G apply to stormwater outfall monitoring conducted per Attachment E.

Attachment H – Bioretention / Biofiltration Design Criteria Corresponding to the Planning and Land Development MCM in the permit, Attachment H describes design specification requirements for bioretention and biofiltration systems.

Attachment I – Developer Technical Information and Guidelines Attachment I requires the City of Long Beach to make available certain reference information and recommended guidelines to the development community. This information may include but not limited to hydromodification control criteria, LID principles and specifications, and construction BMPs.

Notably, all three previous MS4 permits required outfall and receiving water monitoring for a suite of constituents commonly found in stormwater and non-stormwater discharges and addressed by applicable TMDLs. Therefore, Part II.E of this Fact Sheet summarizes water quality in the Los Angeles Region based on existing monitoring for TMDLs and other categories of pollutants.

H. Permit Applications

1. Ventura County Permittees
On January 9, 2015, 180 days prior to the expiration of Order No. R4-2010-0108, all 12 Ventura County Permittees filed a joint reapplication package also known as a Report of Waste Discharge (ROWD) to apply for renewal of their waste discharge requirements that serve as an NPDES permit to discharge stormwater and authorized and conditionally exempt non-stormwater through their MS4 to surface waters. Specifically, the reapplication package was submitted on behalf of the Ventura Countywide Stormwater Quality Management Program, which consists of the Ventura County Watershed Protection District, the County of Ventura, and the incorporated cities of Camarillo, Fillmore, Moorpark, Ojai, Oxnard, Port Hueneme, Ventura, Santa Paula, Simi Valley, and Thousand Oaks.

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The Los Angeles Water Board evaluated the Ventura County Permittees’ reapplication package and deemed it complete per federal stormwater regulations contained in the U.S. EPA Interpretive Policy Memorandum on Reapplication Requirements for Municipal Separate Storm Sewer Systems; Final Rule, August 9, 1996 (61 Fed Reg. 41697).

2. Los Angeles County Permittees
By July 3, 2017, 180 days prior to the expiration of Order No. R4-2012-0175 as amended by State Water Board Order WQ 2015-0075 and Los Angeles Water Board Order No. R4-2012-0175-A01, the 86 Los Angeles County Permittees submitted a total of 29 reapplication packages to discharge stormwater and authorized and conditionally exempt non-stormwater through their MS4 to surface waters. Out of the 29 reapplication packages, 19 were submitted by groups of Permittees and 10 were submitted individually.

The Los Angeles Water Board evaluated these 29 reapplication packages and deemed them complete per federal stormwater regulations contained in the U.S.

EPA Interpretive Policy Memorandum on Reapplication Requirements for Municipal Separate Storm Sewer Systems; Final Rule, August 9, 1996 (61 Fed Reg. 41697).

3. City of Long Beach
On October 1, 2018, 180 days prior to the expiration of Order No. R4-2014-0024 as amended by Los Angeles Water Board Order No. R4-2014-0024-A01, the City of Long Beach submitted a reapplication package to discharge stormwater and authorized and conditionally exempt non-stormwater through its MS4 to surface waters.

The Los Angeles Water Board evaluated the City of Long Beach’s reapplication package and deemed it complete per federal stormwater regulations contained in the U.S. EPA Interpretive Policy Memorandum on Reapplication Requirements for Municipal Separate Storm Sewer Systems; Final Rule, August 9, 1996 (61 Fed Reg. 41697).

III. APPLICABLE FEDERAL AND STATE LAWS, REGULATIONS, PLANS, AND POLICIES The provisions contained in the Order are based on the requirements and authorities described in the Order’s Findings and below. These include the federal Clean Water Act and implementing regulations, the California Water Code, and applicable statewide and regional water quality control plans and policies.

A. Municipal Separate Storm Sewer System Requirements
The 1972 Clean Water Act (CWA)14 established the NPDES Program to regulate the discharge of pollutants from point sources to waters of the United States. However, pollution from stormwater and dry-weather urban runoff was largely unabated for over a decade. In response to the 1987 Amendments to the Clean Water Act, U.S. EPA developed Phase I of the NPDES Storm Water Permitting Program in 1990, which established a framework for regulating municipal, industrial, and construction discharges of stormwater and non-stormwater. The Phase I program addressed sources of stormwater and dry-weather urban runoff that had the greatest potential to 14 Federal Water Pollution Control Act; 33 U.S.C. § 1251 et seq., which, as amended in 1977, is commonly known as the Clean Water Act.

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negatively impact water quality. In particular, under Phase I U.S. EPA required NPDES permit coverage for discharges from medium and large MS4s with populations of 100,000 or more. Operators of MS4s regulated under the Phase I NPDES Storm Water Program were required to obtain permit coverage for discharges of stormwater and nonstormwater from their MS4s to waters of the United States.

In 1990, pursuant to 40 CFR section 122.26(b)(4), the Los Angeles Water Board designated the MS4s owned and/or operated by the incorporated cities and Ventura County within the watersheds of Ventura County, and by the incorporated cities and Los Angeles County within the coastal watersheds of Los Angeles County as a large MS4 due to the total populations of Los Angeles County and Ventura County and the interconnected nature of the Permittees’ MS4s. The total population of the cities and unincorporated areas in Ventura County covered by the Order was approximately 823,318 in 2010 and has increased by approximately 3.3% to 850,967 in 2018 according to the United States Census. The total population of the cities and unincorporated areas in Los Angeles County covered by the Order was approximately 9,505,484 in 2010 and has increased by approximately 2.9% to 9,786,075 in 2018, according to the United States Census.

B. Water Quality Control Plans
The CWA requires the Los Angeles Water Board to establish water quality standards for each water body in its region. Water quality standards include beneficial uses, water quality objectives that are established at levels sufficient to protect those beneficial uses, and an antidegradation policy to prevent degrading high-quality waters unless specific circumstances apply.

1. Water Quality Control Plan - Los Angeles Region
The Los Angeles Water Board’s Water Quality Control Plan - Los Angeles Region (hereinafter Basin Plan) designates beneficial uses, establishes water quality objectives, and contains implementation programs and policies to achieve those objectives for all waters in the Los Angeles Region. Pursuant to CWC Section 13263(a), the requirements of the Order implement the Basin Plan. The beneficial uses applicable to the surface water bodies that receive discharges from the Permittees’ MS4 are identified in Chapter 2 of the Basin Plan and generally include Municipal and Domestic Supply (MUN); Agricultural Supply (AGR); Industrial Service Supply (IND); Industrial Process Supply (PROC); Ground Water Recharge (GWR); Freshwater Replenishment (FRSH); Navigation (NAV); Hydropower Generation (POW); Water Contact Recreation (REC-1); Limited Contact Recreation (LREC-1); Non-Contact Water Recreation (REC-2); Commercial and Sport Fishing (COMM); Warm Freshwater Habitat (WARM); Cold Freshwater Habitat (COLD); Estuarine Habitat (EST); Preservation of Areas of Special Biological Significance (BIOL); Wildlife Habitat (WILD); Preservation of Rare and Endangered Species (RARE); Marine Habitat (MAR); Wetland Habitat (WET); Migration of Aquatic Organisms (MIGR); Spawning, Reproduction, and/or Early Development (SPWN); and Shellfish Harvesting (SHELL).

2. Ocean Plan
In 1972, the State Water Board adopted the Water Quality Control Plan for Ocean Waters of California (Ocean Plan). Since the adoption of Order No. R4-2010-0108, Order No. R4-2012-0175, and Order No. R4-2014-0024, the State Water Board adopted various amendments to the Ocean Plan. One of the most recent

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amendments that has become effective was adopted on August 7, 2018 to incorporate bacteria provisions and a water quality standards variance policy. OAL approved it on February 4, 2019 and U.S. EPA approved it on March 22, 2019.

Additionally, on April 2, 2019, the State Water Board further revised the Ocean Plan through Resolution No. 2019-0015 (incorporating state wetland definition and procedures for discharges of dredged or fill material to waters of the state). OAL approved it on August 28, 2019 and it became effective on May 28, 2020. The Ocean Plan is applicable, in its entirety, to the ocean waters of the State. To protect beneficial uses, the Ocean Plan establishes water quality objectives and a program of implementation. Pursuant to California Water Code section 13263(a), the requirements of the Order implement the Ocean Plan. The Ocean Plan identifies beneficial uses of ocean waters of the State to be protected, which include Industrial Water Supply (IND); Water Contact (REC-1) and Non-Contact Recreation (REC-2), including aesthetic enjoyment; Navigation (NAV); Commercial and Sport Fishing (COMM); Mariculture; Preservation and Enhancement of Designated Areas of Special Biological Significance (ASBS); Rare and Endangered Species (RARE); Marine Habitat (MAR); Fish Migration (MIGR); Fish Spawning (SPWN); and Shellfish Harvesting (SHELL). All MS4 discharges into the Pacific Ocean must protect the existing and designated uses identified in the Ocean Plan and Basin Plan.

3. Inland Surface Waters, Enclosed Bays, and Estuaries Plan (ISWEBE) Since the adoption of Order No. R4-2010-0108, Order No. R4-2012-0175, and Order No. R4-2014-0024, the State Water Board adopted various provisions, which make up, collectively, the Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries (ISWEBE) of California. Part 1 Trash Provisions was adopted by the State Water Board on April 7, 2015 through Resolution No. 2015- 0019. OAL approved it on December 2, 2015 and U.S. EPA approved it on January 12, 2016. Part 2 Tribal Subsistence Beneficial Uses and Mercury Provisions was adopted by State Board on May 2, 2017 through Resolution No. 2017-0027. OAL approved it on June 28, 2017 and U.S. EPA approved it on July 14, 2017. Part 3 Bacteria Provisions and Variance Policy was adopted by State Board on August 7, 2018 through Resolution No. 2018-0038. OAL approved it on February 4, 2019 and U.S. EPA approved it on March 22, 2019. The State Wetland Definition and Procedures for Discharges of Dredged or Fill Material to Waters of the State was adopted by State Board on April 2, 2019 through Resolution No. 2019-0015. OAL approved it on August 28, 2019 and it became effective on May 28, 2020. The Toxicity Provisions were adopted by the State Water Board on December 1, 2020.

The Toxicity Provisions are not yet in effect. The Toxicity Provisions will take effect upon approval by the California Office of Administrative Law for purposes of state law and upon approval by the U.S. Environmental Protection Agency for purposes of federal law. The ISWEBE is applicable to various discharges in the Order.

4. Statewide Trash Provisions
To control trash, the State Water Board on April 7, 2015, adopted an Amendment to the Water Quality Control Plan for Ocean Waters of California (Ocean Plan) for Trash Provisions and Part 1 Trash Provisions of the Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries. Together, they are collectively referred to as “the Trash Amendments.” The Trash Amendments do the following: (1) establish a narrative water quality objective for trash, (2) establish corresponding applicability, including an exception for those waters within the

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jurisdiction of the Los Angeles Water Board for which trash TMDLs are in effect prior to the effective date of the Trash Amendments,15 (3) establish a prohibition on the discharge of trash, (4) provide implementation requirements for permitted storm water and other discharges, (5) set a time schedule for compliance, and (6) provide a framework for monitoring and reporting requirements. The Los Angeles Water Board is required to implement the new Trash Provisions through NPDES permits issued pursuant to Federal Clean Water Act section 402(p), including MS4 permits.

The water quality objective established by the Trash Provisions serves as a water quality standard federally mandated under Clean Water Act section 303(c) and the federal regulations. (33 United States Code section 1312, 40 Code of Federal Regulations section 131.) This water quality standard was specifically approved by U.S. EPA following adoption by the State Water Board and approval by the Office of Administrative Law. Further, the water quality standard expected to be achieved pursuant to the Trash Provisions may allow each waterbody subsequently determined to be impaired by trash to not be placed on the Clean Water Act section 303(d) list, obviating the need for the development of a TMDL for trash for each of those waterbodies. (33 United States Code section 1313(c); 40 Code of Federal Regulations section 130.7.). In those cases, the specific actions that will be carried out by the Permittee substitute for some or all the actions that would otherwise be required consistent with a waste load allocation in a trash TMDL. (40 Code of Federal Regulations section 122.44, subdivision (d)(1)(vii)(B).) The Trash Amendments are applicable to various discharges in the Order and the Order implements the Trash Amendments.

5. Sediment Quality
In 2008, the State Water Board adopted the Water Quality Control Plan for Enclosed Bays and Estuaries – Part 1, Sediment Quality Provisions. It is was most recently amended on June 5, 2018 and became effective on March 11, 2019. This plan supersedes other narrative sediment quality objectives and establishes new sediment quality objectives and related implementation provisions for specifically defined sediments in most bays and estuaries. Requirements of the Order implement sediment quality objectives of this plan.

C. National Toxics Rule (NTR) and California Toxics Rule (CTR) U.S. EPA adopted the National Toxics Rule (NTR)16 on December 22, 1992, and later amended it on May 4, 1995 and November 9, 1999. About forty criteria in the NTR applied in California. On May 18, 2000, U.S. EPA adopted the California Toxics Rule (CTR).17 The CTR promulgated new toxics criteria for California and, in addition, incorporated the previously adopted NTR criteria that were applicable in the state. The CTR was amended on February 13, 2001. The CTR was most recently amended on November 15, 2018 to withdraw the freshwater criteria for lead applicable to certain waters of California because the State of California adopted, and the U.S. EPA approved a site-specific objective for lead for the Los Angeles River and its tributaries. 15 The exception includes the following watersheds and waterbodies: Los Angeles River Watershed, Ballona Creek, Malibu Creek Watershed, Santa Monica Bay Nearshore and Offshore, San Gabriel River East Fork, Revolon Slough and Beardsley Wash, Ventura River Estuary, Machado Lake, Lake Elizabeth, Lake Hughes, Munz Lake, Peck Road Park Lake, Echo Park Lake, Lincoln Park Lake and Legg Lake. 16 40 CFR § 131.36.
17 Policy for Implementation of Toxics Standards for Inland Surface Waters, Enclosed Bays, and Estuaries of California, (65 Federal Register 31682-31719 (May 18, 2000)), adding 40 CFR § 131.38.

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(83 Fed. Reg. 52163-52168 (Oct. 16, 2018)). These rules contain federal water quality criteria for priority pollutants. The requirements of the Order are consistent with the NTR (40 CFR section 131.36) and CTR (40 CFR section 131.38).

D. Endangered Species Acts
The Order does not authorize any act that results in the taking of a threatened or endangered species or any act that is now prohibited, or becomes prohibited in the future, under either the California Endangered Species Act (CESA, Fish and Game Code, §§ 2050 to 2089.25) or the federal Endangered Species Act (ESA, 16 U.S.C.A., §§ 1531 to 1544). The requirements of the Order are designed to maintain water quality and prevent a condition of pollution, contamination, or nuisance in waters of the United States. Permittees remain independently responsible for meeting all applicable requirements under CESA and ESA.

E. NPDES Electronic Reporting Rule (e-Rule)
40 Code of Federal Regulations part 127 requires NPDES permittees to electronically report information and also requires authorized states implementing the NPDES program to ensure that the required minimum set of data in part 127, Appendix A, is electronically transferred to U.S. EPA in a “timely, accurate, complete and nationally consistent manner fully compatible with U.S. EPA’s national NPDES data system.” The rule does not add new reporting requirements on NPDES regulated entities; rather it substitutes paper-based filings with electronic transmission. The State’s existing electronic reporting system for stormwater discharges (Stormwater Multiple Application and Report Tracking System (SMARTS)), which is compliant with U.S. EPA’s CrossMedia Electronic Reporting Rule (40 Code of Federal Regulations part 3), does not currently accommodate the collection from MS4 dischargers and reporting to U.S. EPA of all applicable Appendix A data in a “nationally consistent manner fully compatible with U.S. EPA’s national NPDES data system.” Electronic reporting requirements for those data will be implemented when the State develops an approved system. On April 30, 2019, U.S. EPA proposed changes to the NPDES e-Rule, in Appendix A, to update data elements applicable to regulated MS4s to be consistent with existing MS4 regulations.

On February 28, 2020, U.S. EPA proposed the “Phase 2 Extension Rule,” extending the December 21, 2020 deadline to December 21, 2025 for electronic submittal of annual reports.
18 F. Monitoring and Reporting
Section 308(a) of the federal CWA, and 40 CFR sections 122.41(h), (j)-(l), 122.41(i), and 122.48, require that all NPDES permits specify monitoring and reporting requirements. Federal regulations applicable to large and medium MS4s also specify additional monitoring and reporting requirements. These monitoring requirements for MS4 discharges are prescriptive and require the permitting agency to include requirements for both stormwater and non-stormwater effluent sampling at representative outfalls, representative receiving water monitoring, sampling of specific pollutants, monitoring at specified intervals (e.g., at least three storm events per year), use of analytical methods specified in 40 CFR Part 136, and use of field collection methods. (40 CFR §§ 122.26(d)(2)(i)(F) & (d)(2)(iii)(D), 122.42(c).) California Water Code Section 13383 authorizes the Los Angeles Water Board to establish monitoring, inspection, entry, reporting, and recordkeeping requirements. The Monitoring and 18 80 Federal Register pp. 64064-64158; 84 Federal Register pp. 18200-182-5; 85 Federal Register pp. 11909-11927.

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Reporting Program in the Order requires monitoring, reporting, and recordkeeping requirements that implement the federal and state laws and/or regulations. This Monitoring and Reporting Program is provided in Attachment E of the Order.

G. Standard Provisions
Standard Provisions, which apply to all NPDES permits in accordance with 40 CFR section 122.41, and additional conditions applicable to specified categories of permits in accordance with 40 CFR section 122.42, are provided in Attachment D of the Order.

Permittees must comply with all standard provisions and with those additional conditions that are applicable under 40 CFR section 122.42 provided in Attachment D of the Order.

Part VI of the Order also includes various provisions applicable to the Permittees. The rationale for the provisions contained in Part VI of the Order is provided in Part VIII of this Fact Sheet.

H. Antidegradation Policy
Federal regulations at 40 CFR section 131.12 require that state water quality standards include an antidegradation policy consistent with federal requirements. The State Water Board established California’s antidegradation policy in State Water Board Resolution No. 68-16 (“Statement of Policy with Respect to Maintaining High Quality of Waters in California”). Where the federal antidegradation policy is applicable, the State Water Board has interpreted Resolution No. 68-16 to incorporate the federal antidegradation policy.19 The Los Angeles Water Board’s Basin Plan implements, and incorporates by reference, both the State and federal antidegradation policies. The permitted discharge must be consistent with the antidegradation provision of 40 CFR section 131.12 and State Water Board Resolution No. 68-16. Resolution No. 68-16 and 40 CFR section 131.12 require that high quality waters be maintained unless degradation is justified based on specific findings. The Los Angeles Water Board finds that the permitted discharges authorized by this Order are consistent with the antidegradation provision of 40 CFR section 131.12 and State Water Board Resolution No. 68-16, as set forth herein.

In the context of the Order, a federal NPDES permit, compliance with the federal antidegradation policy requires consideration of the following. First, the Los Angeles Water Board must ensure that “existing instream uses and the level of water quality necessary to protect the existing uses” are maintained and protected.20 Second, if the baseline quality of a waterbody for a given constituent “exceeds levels necessary to support propagation of fish, shellfish, and wildlife and recreation in and on the water, that quality shall be maintained and protected” through the requirements of the Order unless the Los Angeles Water Board makes findings that: (1) any lowering of the water quality is “necessary to accommodate important economic or social development in the area in which the waters are located”; (2) “water quality adequate to protect existing uses fully” is assured; and (3) “the highest statutory and regulatory requirements for all new and existing point sources and all cost-effective and reasonable best management practices for nonpoint source control” are achieved.21 Under this second tier review, the Board may identify the waters for protection through the public process of a permitting action, as it is here. Before allowing any lowering of high quality water, the Board must 19 State Water Board Order WQ 86-17 (Fay), pp. 16-19.
20 40 CFR § 131.12(a)(1). This provision has been interpreted to mean that, “[i]f baseline water quality is equal to or less than the quality as defined by the water quality objective, water quality shall be maintained or improved to a level that achieves the objectives.” (State Water Board, Administrative Procedures Update, Antidegradation Policy Implementation for NPDES Permitting, 90-004 (APU 90-004), p. 4.) 21 40 CFR § 131.12(a)(2).

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conduct an analysis of alternatives that evaluates practicable alternatives that would prevent or lessen the degradation associated with the discharges permitted. In the context of 40 CFR § 131.12(a)(2)(ii), practicable means “technologically possible, able to be put into practice, and economically viable.”22
The Order must also comply with any requirements of State Water Board Resolution No. 68-16 beyond those imposed through incorporation of the federal antidegradation policy.23 Resolution No. 68-16 requires findings that any lowering of water quality is “consistent with the maximum benefit to the people of the State” and “will not unreasonably affect present and anticipated beneficial use of such water and will not result in water quality less than that prescribed in the policies” and further that the discharge is subject to “waste discharge requirements which will result in the best practicable treatment or control of the discharge.”24 The baseline quality considered in making the appropriate findings is the best quality of the water since 1968, the year of adoption of Resolution No. 68-16, or a lower level if that lower level was allowed through a permitting or other regulatory action, such as establishing a water quality objective, that was consistent with the federal and state antidegradation policies.25 The following analysis assumes, without deciding, that the baseline for antidegradation analysis is 1968.26
22 40 CFR § 131.3(n).
23 See State Water Board Order WQ 86-17 (Fay), p. 23, fn. 11. 24 State Water Board Resolution No. 68-16, Resolve 2. Best practicable treatment or control is not defined in Resolution No. 68-16; however, the State Water Board has evaluated what level of treatment or control is technically achievable using “best efforts.” (See State Water Board Orders WQ 81-5 (City of Lompoc), WQ 82-5 (Chino Basin Municipal Water District), WQ 90-6 (Environmental Resources Protection Council).) A Questions and Answers document on Resolution No. 68-16 by the State Water Board states as follows: “To evaluate the best practicable treatment or control method, the discharger should compare the proposed method to existing proven technology; evaluate performance data, e.g. through treatability studies; compare alternative methods of treatment or control; and/or consider the method currently used by the discharger or similarly situated dischargers . . .The costs of the treatment or control should also be considered . . . .” (Questions and Answers, Resolution No. 68-16, State Water Board (Feb. 16, 1995), pp. 5-6.)
25 APU 90-004, p.4. The baseline for application of the federal antidegradation policy is 1975, which is the date used in 40 CFR § 131.3(e) to define existing uses of a waterbody. For state antidegradation requirements, see also Asociacion de Gente Unida por el Agua (AGUA) v. Central Valley Water Board (2012) 210 Cal.App.4th 1255,1270. The baseline for the application of the state antidegradation policy is generally the highest water quality achieved since 1968, the year the policy was adopted. 26 The baseline may be later than 1968 for two reasons. First, the appropriate baseline is determined by the date on which a policy establishing the level of water quality to protect was effective. (Resolution 68- 16, Resolve 1.) The Region’s Basin Plan has been updated and amended several times since 1971, when it was first adopted, to include new or revised water quality objectives. Second, a permitting action with appropriate antidegradation findings allowing degradation may establish a new baseline consistent with the level of water quality achieved under that permit. The Los Angeles Water Board has regulated the Permittees’ MS4 discharges in the past through permits issued in 1990, 1996, 2001, and 2012 for Los Angeles County; 1999 and 2014 for City of Long Beach; and 1994, 2000, 2009, and 2010 for Ventura County. APU 90-004 acknowledges that no antidegradation analysis is required where the regional water board has no expectation that water quality will be reduced by the permitting action; here, if the water quality achieved under the prior permits had been used as the baseline, arguably, no antidegradation analysis would have been required. (APU 90-004, p. 2.) Nevertheless, this is a new regional permit for Permittees in both Los Angeles and Ventura Counties, and for ease of analysis, 1968 is used herein as the baseline.

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The Board Is Not Required to Make Waterbody by Waterbody and Pollutant by Pollutant Antidegradation Findings:

The Los Angeles Water Board finds that it is not required to conduct a waterbody by waterbody and pollutant by pollutant antidegradation analysis for this Order. The Los Angeles Water Board makes this finding for two reasons. First, the Administrative Procedures Update, Antidegradation Policy Implementation for NPDES Permitting, 90- 004 (APU 90-004), which specifies a waterbody by waterbody and pollutant by pollutant analysis for some permitting actions, does not address permitting for diffuse MS4 discharges. Second, APU 90-004 itself indicates that a waterbody by waterbody and pollutant by pollutant analysis is only required when conducting a “complete” antidegradation analysis; a complete analysis, in turn, is not required where any reduction in water quality is temporally limited and would not result in any long-term deleterious effects on water quality.”27 Here, the Order requires compliance with the non-stormwater discharge prohibition, Receiving Water Limitations and Numeric Effluent Limitations derived from TMDLs designed to bring MS4 discharges and receiving waters into compliance with water quality objectives. The discussion below elaborates on these two reasons.

APU 90-004 is a State Water Board internal guidance document establishing methods for implementing the federal and state antidegradation policies in NPDES permits. APU 90-004 suggests that an antidegradation analysis requires a pollutant by pollutant and waterbody by waterbody analysis in certain contexts, specifically where the discharge at issue is a discrete discharge from a singular facility. However, APU 90-004 has limited value when considering antidegradation in the context of MS4 discharges from diffuse sources, conveyed through multiple outfalls, with multiple pollutants impacting multiple water bodies within region. 28 This interpretation is sensible for this Order, given that reliable data on the baseline water quality is not readily available since 1968 for a region that spans 4,447 square miles and includes 120 miles of coastline, 18,839 acres of lakes, and 1,704 miles of rivers and streams. The Los Angeles Water Board estimates that, there are over 850,000 combinations of waterbodies and pollutants that could potentially require individual consideration in the Region.29 The antidegradation analysis for this Order instead relies on a general assessment of the existing water quality data that is reasonably available to the Los Angeles Water Board and makes findings regarding the social and economic benefits and costs of permitting stormwater and nonstormwater MS4 discharges in accordance with the Order terms.

The Los Angeles Water Board additionally finds that, even if APU 90-004 applies to the issuance of this Order, it requires at most a “simple” antidegradation analysis. APU 90- 27 APU 90-004, p. 2.
28 The State Water Board held so in Order WQ 2015-0075. In Natural Resources Defense Council v. State Water Resources Control Board, the superior court did not invalidate this particular conclusion. (Super.

Ct. Los Angeles County, No. BS156962, Order, March 29, 2021). The State Water Board’s interpretation of its own guidance is entitled to deference. See also State Water Board Order WQ 2018-0002, p. 77 (reaching the same conclusion for agricultural discharges). 29 See, https://www.waterboards.ca.gov/water_issues/programs/water_quality_goals/; the tributary table MasterTribTable.xls (ca.gov); and the Basin Plan for the Coastal Watersheds of Los Angeles and Ventura Counties (Basin Plan), Ch. 2, Tables 2-1 through 2-4a and Beneficial Uses Figures; and Chapter 3. The number could easily be higher if the Los Angeles Water Board incorporated CEDEN data and other information to determine the exact number of waterbodies and waterbody pollutant combinations. If it could be done at all, a pollutant by pollutant, waterbody by waterbody antidegradation analysis would be extremely time consuming and take years to complete.

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004 contemplates that a “simple” antidegradation analysis is appropriate under specified circumstances. In particular, as stated above, APU 90-004 states that a simple antidegradation analysis is allowed when a “Regional Board determines the reduction in water quality is temporally limited and will not result in any long-term deleterious effects on water quality” or where a “Regional Board determines the proposed action will produce minor effects which will not result in a significant reduction of water quality.”30 Here, the Order continues the requirements of the previous permits or imposes equivalent or more protective requirements such that the water quality established under the prior permits is expected to be maintained and improved.

Generally, the prior permits instituted controls such as a prohibition on non-stormwater discharges that are a source of pollutants through the MS4s, receiving water limitations, WQBELs based on TMDLs, and monitoring programs to help ensure that water quality will be maintained at the level it is now, or improve it, and this new Order institutes further controls such as additional TMDL-based WQBELs and receiving water limitations. Therefore, any degradation permitted while controls are continuing to be developed will be temporally limited and will not result in any long-term deleterious effects on water quality.31 Such a finding would not be appropriate if, for example, the Order declined to require long-term compliance with water quality objectives, but that is not the case here.

APU 90-004 does not provide guidance on the scope and content of a simple antidegradation analysis. Nor does it define the terms “temporally limited” or “long term.” Those terms must therefore be interpreted in the context of the types of discharges being permitted and with deference to the best professional judgment of the Los Angeles Water Board.32 The Los Angeles Water Board determines that the findings made below 30 APU 90-004, p. 2. In an unpublished decision, the Second District Court of Appeal affirmed that a simple antidegradation analysis applied to the 2012 Los Angeles County MS4 permit. (Natural Resources Defense Council v. State Water Resources Control Board (2018) 2018 WL 6735201, at *6). 31 See, Order, Part IX.A.4.b, k; B.8; E; G.3
32 During the hearing to consider adoption of this Order on July 16, 2021, NRDC, Heal the Bay, and Los Angeles Waterkeeper (together, the “Environmental Groups”) asserted that if the Los Angeles Water Board adopted the Order with the alternative compliance path outlined in Part X.B.1.b of the Order (referred to in the antidegradation analysis, infra, as “Alternative 5,”), then a simple antidegradation analysis is not appropriate. They asserted that a complete antidegradation analysis is necessary because, since the WMPs were first approved (2015), there is no evidence that there has been any significant improvement in water quality. The Los Angeles Water Board disagrees and finds that water quality effects during a period of multiple years, spanning more than one permit term, are still “temporally limited” and not “long term” in the context of the regulation of MS4 discharges.

MS4 discharges are fundamentally different from those specifically discussed in the APU, such as discharges from discrete point sources like publicly owned treatment works, or POTWs. MS4 discharges are diffuse discharges conveyed through multiple outfalls, with multiple pollutants impacting multiple water bodies within the region. To effectively control and abate pollution to surface waters from MS4 discharges, permittees testified during the hearing on this Order that they need time to plan and implement solutions that are projected to bring impaired waters into attainment. This kind of pollution control and abatement would take time even if WMPs with deemed in compliance provisions were not part of the proposed solutions. The Board, and permittees, understand and expect that more than one permit term may be necessary to adequately plan and construct BMPs or implement other solutions to ensure that impaired waters will be restored.

Furthermore, it is not surprising that, after only one permit term, water quality data do not show marked improvement, because as many permittees testified, the first generation of projects in approved WMPs are only being completed just now. For example, Paul Alva, Principal Engineer at the Los Angeles County

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meet the requirements of a simple antidegradation analysis and are also consistent with an antidegradation analysis done at a generalized level, as appropriate for this Order.

With these findings, based on the information available to it and using its best professional judgment, the Los Angeles Water Board concludes that the discharge will not be adverse to the intent and purpose of the State and federal antidegradation policies. Regardless of APU 90-004’s application, however, the below analysis is consistent with the generalized antidegradation analysis appropriate for this Order and complies with both the federal antidegradation regulations, and with the State antidegradation policy.

The Los Angeles Water Board Makes the Following Antidegradation Findings:

The discharges permitted in the Order are consistent with the antidegradation provisions of 40 CFR section 131.12 and Resolution No. 68-16. The Los Angeles Water Board’s conclusion that the terms and conditions of the Order are consistent with the antidegradation policies is based on the following analysis.

1. Water bodies that do not meet water quality objectives (water bodies that are not high quality):

Most of the receiving waters within the area covered by the Order are not meeting water quality objectives for multiple pollutants associated with MS4s, meaning that they are not attaining water quality objectives necessary to protect beneficial uses.33 This is evidenced in part by the fact that many of these waterbodies are listed on the State’s Clean Water Act section 303(d) List of impaired waters and, additionally, either the Los Angeles Water Board or the U.S. EPA has established numerous TMDLs to address many of the impairments.34 The source assessment for these TMDLs identify MS4 discharges as a source of the impairments. Under both federal and state antidegradation policies, these receiving waters are not considered “high quality” waters for these pollutants. To the extent that data are Department of Public Works, testified on July 16, 2021 that multi-benefit WMP projects such as Magic Johnson Park, Ladera Park, Carriage Crest Park, and Gates Park have either just been completed or will be completed soon. Once those projects are fully operational, and once other, similar projects are built, the Board expects to see measurable improvements in receiving water quality. Indeed, the evidence already indicates WMPs with deemed in compliance are achieving results. As illustrated in Mr. Alva’s presentation to the Board on July 16, 2021, the landscape of water quality has and will continue to vastly improve all over the County, and not just in certain communities, due to WMP construction and implementation.

In summary, the time to plan, construct, and see results from the projects built is a temporal limitation that is as short as practicable and it is appropriate given the nature of the discharges at issue. This is especially true since most of the deemed in compliance provisions have an end point and will expire. (See Order, Part X.B.)
33 This is certainly true of the receiving waters in the more urbanized watersheds throughout the Region during wet weather. See, staff presentations at MS4 Workshops regarding monitoring data, dated 9/13/2018 (Ventura County data); and 7/12/2018 and 5/10/2018 (Los Angeles County data). 34 It should be noted that impaired waters, or waters that are not high quality, are not confined to those listed only on the 303(d) List. There are several reasons for this, including (but not limited to) the fact that the most recent 303(d) List for the Los Angeles Region is based on available data through August 2010. Accordingly, the 303(d) List itself does not reflect all of the waterbodies in the Region that are impaired or fail to meet water quality standards.

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available from 1968, there were few high quality receiving waters in the more urbanized watersheds in the Los Angeles Region even at that time.35 For receiving waters that are not high quality waters, the federal antidegradation policy requires that regulatory actions ensure that existing instream uses and the level of water quality necessary to protect the existing uses is maintained and protected. (40 CFR § 131.12(a)(1).) The Order ensures that existing instream (beneficial) uses and the level of water quality necessary to protect the existing uses is maintained and protected through requirements to not cause or contribute to exceedances of water quality objectives in the receiving water and to restore impaired water bodies.36 This is achieved through the following provisions:
a. The Order requires compliance with receiving water limitations to meet water quality standards in the receiving water either by demonstrating compliance pursuant to Part V of the Order and the Permittee’s monitoring and reporting program pursuant to Part VII of the Order or by implementing an approved Watershed Management Program (WMP) pursuant to Part IX of the Order.

Watershed Management Programs must specify structural and non-structural stormwater and non-stormwater controls that are demonstrated to have a reasonable assurance of achieving compliance with receiving water limitations and that must be implemented in accordance with an approved compliance schedule. The reasonable assurance analysis, or RAA, is 35 See e.g., Water Resources Control Board, State of California, Toxic Substances Monitoring Program, Ten Year Summary Report 1978-1987 (August 1990) (Administrative Record, Order No. 01-082, R0044666 - 44669); The Santa Monica Bay Restoration Project, An Assessment of Inputs of Fecal Indicator Organisms and Human Enteric Viruses from Two Santa Monica Storm Drains (June 1990) (Administrative Record, Order No. 01-082, R0047130 - 47174); Santa Monica Bay Restoration Project, Pathogens and Indicators in Storm Drains Within the Santa Monica Bay Watershed (June 1992) (Administrative Record, Order No. 01-082, R0047688 - 47748); Santa Monica Bay Restoration Project, Storm Drains as a Source of Surf Zone Bacterial Indicators and Human Enteric Viruses to Santa Monica Bay (August 1991) (Administrative Record, Order No. 01-082, R004779 - 47780); James M. Danza, Water Quality and Beneficial Use Investigation of the Los Angeles River: Prospects for Restored Beneficial Use (1994) (Administrative Record, Order No. 01-082, R0048073 - 48204); Southern California Coastal Water Research Project, Annual Report (1987) (Administrative Record, Order No. 01- 082, R0048205 - 48304); National Research Council, Monitoring Southern California’s Coastal Waters (1990) (Administrative Record, Order No. 01-082, R0048306 - 48473); Southern California Coastal Water Research Project, Annual Report (1988-89) (Administrative Record, Order No. 01-082, R0048476 - 48482); City of Los Angeles, Wastewater Program Management Division, Santa Monica Bay Stormwater Pollutant Reduction Study (December 1987) (Administrative Record, Order No. 01-082, R0048485 – 48561); Santa Monica Bay Restoration Project, Santa Monica Bay Characterization Study Chapter 7, Urban Runoff (1993) (Administrative Record, Order No. 01-082, R0048714 - 48733); To California Regional Water Quality Control Board, Stormwater Runoff in Los Angeles and Ventura Counties (June 1988) (Administrative Record, Order No. 01-082, R0050795 - 50888); Heal the Bay’s State of the Marina Report, Marina del Rey (July 9, 1993) (Administrative Record, Order No. 01-082, R0050999 - 0051022); County of Los Angeles, Department of Beaches and Harbors, The Marine Environment of Marina del Rey (October 1991 – June 1992) (Administrative Record, Order No. 01-082, R0051023 - 51344); Prepared for American Oceans Campaign, Chemical Contaminant Release into the Santa Monica Bay, A Pilot Study (June 12, 1993) (Administrative Record, Order No. 01-082, R0051345 - 51557; Report to the Department of Beaches and Harbors, County of Los Angeles, The Marine Environment of Marina del Rey, October 1989 to September 1990 (March 1991) (Administrative Record, Order No. 01-082, R0052394 – 52721).
36 These actions also ensure that discharges will not unreasonably affect present and anticipated beneficial uses and will not result in water quality less than water quality objectives, as required by Resolution No. 68-16.

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quantitative and generally conducted using industry accepted computer modeling to show that proposed WMPs will achieve applicable WQBELs and will not cause or contribute to exceedances of receiving water limitations. This Order requires objective technical demonstrations that any proposed controls, and those controls already in the process of being developed, will address pollutants in MS4 discharges sufficient to meet water quality standards.

Additionally, the Order requires a comprehensive evaluation and update, through the required adaptive management process, of the WMP during the permit term to ensure progress toward achieving WQBELs and receiving water limitations.
b. The Order requires Permittees to comply with WQBELs and/or receiving water limitations consistent with the assumptions and requirements of TMDL WLAs assigned to MS4 discharges established in 45 TMDLs applicable to water bodies within the Los Angeles Region to restore water quality sufficient to protect the beneficial uses of the impaired water bodies. c. The Order requires Permittees to develop and implement stormwater management programs consisting of six major program elements (MCMs), and effectively prohibit non-stormwater discharges that are a source of pollutants through the MS4 to receiving waters.
d. The Order includes requirements for extensive monitoring and reporting designed to identify changes in water quality at hundreds of outfall monitoring sites.

These provisions are collectively designed to halt any further degradation of impaired water bodies and improve the quality of such waters to a level protective of existing uses over a time schedule that is as short as possible. The antidegradation policies do not explicitly or implicitly override the authority and discretion the Clean Water Act and the Water Code grant to the Los Angeles Water Board as to how it structures a permit to ensure water quality necessary to protect beneficial uses. The law does not require immediate restoration of impaired water bodies nor does it require an immediate prohibition of discharges that contribute to an exceedance in the waterbody. Rather, federal regulations at 40 CFR section 122.47 allow NPDES permits, including MS4 permits, to have compliance schedules. Similarly, Water Code section 13263, subdivision (c), authorizes the Los Angeles Water Board to include a time schedule for achieving water quality objectives in waste discharge requirements. Where a TMDL has been established, Water Code section 13242 states that the TMDL implementation plan, as incorporated into the water quality control plan, shall include a time schedule for actions to be taken. When issuing waste discharge requirements, Water Code section 13263 requires regional boards to implement any relevant water quality control plans that have been adopted. Certainly, water quality objectives must be achieved; but the law, as cited above, recognizes and allows for the fact that it can take time to restore or achieve the objectives.37 In this regard, some impaired 37 Additionally, and as discussed elsewhere in this Fact Sheet, while MS4 permits must include a technology-based standard of effectively prohibiting non-storm water discharges through the MS4 and reducing pollutants in the discharge to the MEP, requiring strict compliance with water quality standards (e.g., by requiring immediate compliance with receiving water limitations or water quality based effluent limitations) is at the discretion of the permitting agency (33 U.S.C. § 1342(p)(3)(B); Defenders of Wildlife v. Browner (9th Cir. 1999) 191 F.3d 1159, 1166-67). This Order imposes numeric water quality based

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water bodies may stagnate or, rarely, continue to degrade38 for a period of time before showing improvement. This period of time may be as long as multiple years.

This is not contrary to the authorities for compliance schedules stated above and is not contrary to the antidegradation policies.39

2. High quality water bodies:

Some of the waterbodies within the area covered by the Order may be high quality waters with regard to some pollutants. Some of these waterbodies may be currently high quality as compared to currently applicable objectives.40 Others of these waterbodies may be currently impaired but may be classified as high quality waters because they were historically high quality for certain pollutants. MS4 discharges of stormwater and non-stormwater into such water bodies may have resulted in lowering of the quality of the water bodies since 1968 with regard to the pollutants in the discharge.

For high quality water bodies,
41 the Los Angeles Water Board finds as follows:
a. Practicable Alternatives: The Los Angeles Water Board has evaluated a range of practicable alternatives that would prevent or lessen any degradation effluent limitations to implement TMDL WLAs and requires compliance with receiving water limitations for all constituents in the MS4 discharges. The fact that the Board also allows reasonable time schedules to achieve compliance with the numeric effluent limitations and receiving water limitations is not contrary to the law for this additional reason.
38 Certain commenters have argued that any further degradation of water bodies not meeting objectives violates the antidegradation policies and that such further degradation has occurred under the 2012 Los Angeles County MS4 Order. As a matter of fact and science, the Los Angeles Water Board generally disagrees with assertions made that water bodies not meeting water quality objectives have continued to degrade (or that they are accelerating) under the 2012 Los Angeles County MS4 Order or will continue to degrade under this Order. However, even if these assertions were true, the law does not preclude limited and temporary further degradation while a permittee works to implement measures in compliance with a compliance schedule, as set forth above.
39 With regard to waterbodies that are not high quality, the antidegradation policies do not require socioeconomic findings justifying any continued degradation of such waterbodies that may occur while the Permittees implement requirements in accordance with a compliance schedule. Even if such findings were required, the Los Angeles Water Board finds that this potential, limited, and temporary further lowering of water quality is justified for the same reasons articulated in the Section titled, “High Quality Water Bodies,” Part III.H.2 of this Fact Sheet, infra.
40 See, staff presentations at MS4 Workshops regarding monitoring data (dated 9/13/2018 (Ventura County data); and 7/12/2018 and 5/10/2018 (Los Angeles County data)), which summarize and evaluate data collected under the three prior MS4 permits. For example, at the mass emissions stations in the Ventura River, Calleguas Creek, and Malibu Creek watersheds, concentrations of copper, lead and zinc in wet weather are below water quality objectives, or TMDL numeric targets where applicable. 41 The quality of some currently high quality waters that are close to or at objectives may degrade below water quality objectives temporarily while Permittees plan for, develop, and implement appropriate controls in accordance with the compliance schedules in the Order and some historically high quality waters may stagnate or continue to degrade below water quality objectives during the same period. The Los Angeles Water Board finds that the potential, limited, and temporary lowering of water quality below the objectives is authorized by 40 CFR § 122.47 and the time schedule provisions of the Water Code set out in the Section titled, “Water bodies that do not meet the water quality objectives (water bodies that are not high quality)” Part III.H.1 of this Fact Sheet, supra, and, to the extent any findings are required under the antidegradation policies, is justified for the same reasons articulated in this Part III.H.2 of this Fact Sheet, “High quality water bodies.”

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associated with permitted MS4 discharges to high quality waters. These alternatives are discussed below.
i. Alternative 1 - Complete prohibition on some or all pollutants in MS4 nonstormwater discharges to high quality waters: This alternative would prohibit MS4 discharges of some or all pollutants in non-stormwater to high quality receiving waters. By eliminating these discharges, pollutants from non-stormwater discharges would not reach high quality receiving waters during dry weather and thus not cause any degradation. In high quality water areas, this alternative could require the permittees to either divert all non-stormwater to a facility for treatment, or retain all nonstormwater through retention basins, infiltration galleries, and other controls that would prevent non-stormwater from reaching surface waters through storage, infiltration, or reuse. Alternatively, Permittees could install specific pollutant control measures that prevent specific pollutants from being discharged through the MS4.
ii. Alternative 2 - Complete prohibition on some or all pollutants in MS4 stormwater discharges to high quality waters: This alternative would prohibit MS4 discharges of some or all pollutants in stormwater to high quality receiving waters. By eliminating these discharges, pollutants from stormwater would not reach high quality receiving waters during wet weather and not cause any degradation. As wet weather will always occur, this alternative could require the permittees to either divert all stormwater in the MS4 to a facility for treatment, or retain all stormwater through retention basins, infiltration galleries, and other controls that would prevent stormwater from reaching surface waters through storage, infiltration, or reuse. Permittees could also install pollutant control measures that are specific to preventing specific pollutants from being discharged through the MS4.
iii. Alternative 3 - Stricter Pollutant Controls for New Development and Redevelopment in areas with high quality waters: This alternative would subject new development and redevelopment projects to more stringent water quality and runoff reduction criteria, such as retention of the 95th percentile, 24-hour storm volume instead of the 85th percentile, 24-hour storm volume. This alternative would hold new developments and redevelopments to more stringent performance criteria that would eliminate stormwater discharges from most storms.
iv. Alternative 4 - Watershed Management Program alternative compliance option without deemed compliance with Receiving Water Limitations for any high quality waters: This alternative would allow the permittees to implement approved WMPs, with customized control measures, to achieve Receiving Water Limitations, WQBELs, and other requirements.

With this alternative, a permittee would not be deemed in compliance with Receiving Water Limitations for high quality waters while they are fully and timely implementing an approved WMP.
v. Alternative 5 - Watershed Management Program alternative compliance option with deemed compliance with Receiving Water Limitations for some high quality waters: This alternative would allow the permittees to implement approved WMPs, with customized control measures, to

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achieve Receiving Water Limitations, WQBELs, and other requirements.

With this alternative, a permittee would be deemed in compliance with Receiving Water Limitations for some high quality waters, primarily those waters that may have been high quality historically but are not currently high quality,42 while they are fully and timely implementing an approved WMP.43 This alternative was incorporated as a set of terms in the 2012 Los Angeles MS4 permit and the 2014 City of Long Beach MS4 permit. vi. Alternative 6 - Establishment of WQBELs for MS4 discharges to high quality waters: This alternative includes the Board establishing WQBELs for MS4 discharges of certain pollutants to high quality waters. These WQBELs would apply to both stormwater and non-stormwater discharges. The 2010 Ventura County, 2012 Los Angeles County, and 2014 City of Long Beach MS4 permits only include WQBELs where they are based on TMDL wasteload allocations applicable to MS4 discharges (i.e., for impaired waters and not high quality waters). This alternative would require the Board to establish WQBELs where no TMDLs have been established.
b. Economic and Social Development Considerations and Consistency with Maximum Benefit to the People of the State: The Board incorporated Alternative 5 and aspects of Alternatives 1 and 2 into the Order. These alternatives may allow limited degradation of high quality water bodies by MS4 discharges, but these alternatives ultimately require MS4 discharges to meet and not fall below water quality standards.

Such degradation of high quality waters is necessary to accommodate important economic or social development in the area and is consistent with the maximum benefit to the people of the state for the following reasons:
i. Alternatives 1 and 2, if implemented as full prohibitions, would hamper important social and economic development.
(a) The MS4 discharges of stormwater and non-stormwater in certain circumstances are to the maximum benefit to the people of the state because they may be necessary for flood control and public safety.44 MS4 discharges also can assist with maintaining instream flows that support beneficial uses.45 In addition, complete diversion or 42 See, discussion infra at Parts III.H.1.d and III.H.2.b of this Fact Sheet. 43 Under this alternative, and in accordance with WQ-2020-0038, Permittees must develop compliance schedules for WMPs that (among other things) include a final date for achieving receiving water limitations as soon as possible. (State Board Order WQ-2020-0038 at p. 77; see, also, Order, Part IX.B.9.c.iii.c; Part X, generally.)
44 SCCWRP Technical Report 520, Concept Development: Design Storm for Water Quality in the Los Angeles Region, October 2007; LASGRWC. Storm Water: Asset not Liability. [n.d.] [Noting at p. 1 the potential trade-offs between water quality and ensuring public safety, including protecting property from flood damage and maintaining passable roadways.]
45 For instance, the Los Angeles River Flows Project studied the impacts of reduced flows on beneficial uses in the Los Angeles River as a pilot application of the California Environmental Flows Framework.

At the beginning of this project, Los Angeles Water Board staff presented on the importance of minimum flows for recreation and wildlife in both concrete and soft-bottom channels of the river (https://www.waterboards.ca.gov/water_issues/programs/docs/lar/002_r4_la_river_info_item_2017110 3rev.pdf). Wading shorebirds, for example, rest and feed in the shallow waters of the concrete lined portion of the lower Los Angeles River. The final report for the project, “Process and Decision Support

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retention of MS4 discharges that would reach the MS4 and receiving water would require extensive structural controls that are not technologically feasible in many locations.46
(b) The vast majority of the Permittees are cities and counties that provide essential and valuable public services. Part XIII of this Fact Sheet considers economics, including Permittees’ compliance costs associated with meeting the requirements of the Order. Controlling stormwater discharges to the point that there is no potential degradation of any potentially high quality waters by requiring complete diversion or retention would be an enormous opportunity cost that could preclude MS4 permittees from spending substantial funds on other important social and economic needs. This may manifest itself in the reduction of some public services or prevent other public services from being provided in the first place.

Permittees have previously provided public comments (on the Tentative Order and during consideration of the 2012 Los Angeles County MS4 Permit) that spending limited municipal resources on immediately addressing all pollutants in MS4 discharges (all stormwater and non-stormwater discharges) will adversely impact municipal budgets, such as fire and police protection, as well as other social services.47
(c) As another example, and specifically in response to comments received, the Los Angeles Water Board conducted an analysis (based on cited sources in footnote no. below), that estimates the equivalent public benefit that may be provided through affordable housing and services if full retention and diversion is not required.

The results of the analysis support the finding that the social and economic benefits of a society where there would be significantly fewer unhoused residents would be far greater than the additional benefits created by taking water quality from the point where water quality standards are achieved to a level of higher quality that may only be achieved with full retention.48 The same funds that would Tools for Evaluating Flow Management Targets to Support Aquatic Life and Recreational Beneficial Uses of the Los Angeles River,” quantified the flow ranges associated with different species, habitats, and recreational uses in the river and evaluated the impacts of various combinations of reductions in wastewater, stormwater, and non-stormwater discharges. In general, if all discharges were eliminated, there would not be enough flow to protect beneficial uses including habitat for local plant and animal species.
46 Southern California Coastal Water Research Project. Concept Development: Design Storm for Water Quality in the Los Angeles Region, Technical Report 520. October 1, 2007. 47 See, e.g., City of South El Monte comment letter on 2012 Los Angeles MS4 Permit, July 23, 2012 (prior to the time the deemed in compliance pathway was included in the permit) (“The City is dedicated to the protection and enhancement of water quality. The City, however, has other functions that require funding as well. If this Permit is adopted as proposed, even in the best case scenario, spending cuts to other crucial services such as police, fire, and public works are certain. The permittee dwindling general funds simply cannot take the financial hit the Permit is poised to impose on them.”). 48 In 2012, Los Angeles County projected that it would cost $120B, or $134.8B in 2019 dollars, for complete diversion or retention of MS4 discharges, whereas the cost of implementing EWMPs, which require addressing the 85th percentile, 24-hour storm event or otherwise reducing or treating stormwater discharges to attain water quality standards, was estimated by Board staff to be $21.0B-$21.3B (see Section XIII, Economic Considerations). Instead of using this cost differential of $113.5B-$113.8B to further improve

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have to be used to prevent all MS4 discharges (as opposed to only 85% of those discharges) could be invested instead in addressing homelessness, and could support affordable housing and several decades of supportive services for a significant number of residents at-risk of being unhoused.49
(d) The significantly higher cost of complete stormwater diversion or retention could lead to increased fees for residents with little benefit waters that would already have achieved water quality standards, thereby already being able to support designated beneficial uses, this money could be better spent addressing the homeless problem in the region. In 2020, there were an estimated 66,436 unhoused residents in Los Angeles County. (Los Angeles Homeless Services Authority. 2021. 2020 Greater Los Angeles Homeless Count – Total Point-In-Time Homeless Population by Geographic Areas. https://www.lahsa.org/documents?id=4692-2020-greater-losangeles-homeless-count-total-point-in-time-homeless-population-by-geographic-areas.pdf.) The median cost in Los Angeles County of constructing a permanent housing unit for the homeless is about $531,000. (Galperin, Ron. 2019. The High Cost of Homeless Housing: Review of Proposition HHH. Ron Galperin LA Controller. https://lacontroller.org/audits-and-reports/high-cost-of-homeless-housing-hhh/.) Supportive services to address the homeless housing gap were estimated in 2016 to be $428.8M per year, or $455.3M in 2019 dollars. (Los Angeles Homeless Services Authority. 2016. Report on Homeless Housing Gaps in the County of Los Angeles. https://homeless.lacounty.gov/wp-content/uploads/2019/02/Report-onHomeless-Housing-Gaps-in-the-County-of-Los-Angeles-1-2016-1....pdf) Adjusting for the increase in the homeless population since then yields an estimated annual cost in supportive services of $1.2B in 2019 dollars. (Assuming the same supportive services cost per person estimated in 2016, multiplied by the number of homeless residents in LA County in 2020.) The stormwater capture cost differential could build enough units to house every homeless person in Los Angeles County and pay for supportive services for the next 67 years, even with the conservative assumption of one person per housing unit. Housing a homeless person in Los Angeles County results in average cost savings of about $2,731 per person per month in 2019 dollars in terms of reduced need for public services, such as medical and policing expenses. (Economic Roundtable. 2008. Where We Sleep: Costs when Homeless and Housed in Los Angeles. https://economicrt.org/wp-content/uploads/2009/11/Where_We_Sleep_2009.pdf) This means that there would be annual cost savings of about $2.2B from housing all homeless residents in Los Angeles County, and over 67 years the cost savings would be about $145.1B-$145.8B, greater than the stormwater capture cost differential of $113.5B-$113.8B. An analysis of Ventura County finds similar results where each of its 1,743 unhoused residents could be provided permanent housing for at least 55 years with its stormwater capture cost differential, assuming that Ventura County’s cost of full capture would be their estimated MS4 compliance costs multiplied by the same ratios of Los Angeles County’s E/WMP costs to cost of full stormwater capture, yielding cost differentials ranging from $2.5B-$23.4B (https://www.vcstar.com/story/news/2020/12/12/covid-ventura-county-continuum-of-care-2021-homelesscount/3868785001/). This analysis was also based on an average cost per unit of $480,000 for housing the homeless in Ventura County in 2019 and the same supportive services cost per person as in LA County (https://humanimpact.org/wp-content/uploads/2020/10/HIP-Ventura-County-Lets-Invest-Sources2020.pdf). Detailed calculations can be found in the administrative record. It can be expected that there would be substantial additional benefits for these housed residents and for the local economy from being more fully able to engage in society.
49 Contrary to what the Environmental Groups asserted during their closing statement to the Board on July 16, 2021, this discussion is only an example used to show how different permit requirements could affect municipal spending, and it is not a finding that the funds not expended on MS4 controls would in fact be spent on ending homelessness or that in deciding whether to approve the permit with deemed compliance provisions that the board is presented with a zero sum choice—housing or water quality.

Municipalities’ budgets are not unlimited, so when one slice of the budget pie gets bigger, another slice may get smaller. Permittees who testified during the hearings on July 8, 9, and 16, 2021, and those who testified during the 2012 Los Angeles County MS4 hearings, have identified certain services that would be cut, such as police and fire, if they were required to immediately comply with all receiving water limitations.

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in return after water quality standards have been met, or beyond the requirement to address the 85th percentile, 24-hour storm event. The literature is sparse on the impact of MS4 project costs on user fees, but Kea et al. (2016) found higher rates of user fee establishment in the years directly before and after MS4 permit deadlines,50 indicating that utilities often rely on user fees to meet permit requirements.

It is also possible that higher costs could be passed down to residents through increased housing prices driven by higher impact fees, which cities often charge developers to help fund public services, or higher construction costs. The literature finds that overall impact fees lead to higher home prices.51 Requiring complete stormwater diversion or retention from properties could also lead to higher construction costs for housing, which is one of the drivers of higher home prices.52 There is extensive literature showing that higher housing prices are associated with proximity to cleaner waterbodies,53 which provide benefits to society. However, higher housing prices driven by higher impact fees or construction costs that do not contribute toward discernible improvements in water quality would likely provide lower marginal benefits compared to a scenario where residents could avoid additional housing costs by not having to pay higher impact fees or construction costs in a region where housing costs are already high, or a scenario where this cost could be spent on more pressing public services or societal problems (see, for example, footnote , supra.)
ii. However, aspects of Alternatives 1 and 2 are practicable and have been incorporated into this Order. The Order generally implements a prohibition on trash discharges through the installation of full capture systems or controls to achieve full capture equivalency, or alternative 50 Kea, Kandace, Randel Dymond, Warren Campbell. 2016. An Analysis of Patterns and Trends in United States Stormwater Utility. Journal of the American Water Resources Association, 52(6). See, also, Comment Letter on 2012 Los Angeles MS4 Permit from City of Lakewood, Lisa A. Rapp, Director of Public Works, July 23, 2012, Comment Letter from City of La Verne, Daniel W. Keesey, Director of Public Works, July 23, 2012, and Comment Letter from LA Permit Group, July 23, 2012 (discussing the need to, and difficulty of, levying additional special taxes to pay for the permit). 51 Mathur, Shishir, Paul Waddell, and Hilda Blanco. 2004. The Effect of Impact Fees on the Price of New Single-family Housing. Urban Studies, 41(7); Ihlanfeldt, Keith R. and Timothy M. Shaughnessy. 2004. An empirical investigation of the effects of impact fees on housing and land markets. Regional Science and Urban Economics, 34(6); Mathur, Shishir. 2013. Do All Impact Fees Affect Housing Prices the Same? Journal of Planning Education and Research, 33(4).
52 Emmons, William R. 2019, Sept. 5. Construction Costs, Not Another Housing Bubble, Are Driving House Prices Higher. St. Louis Fed On the Economy Blog. https://www.stlouisfed.org/on-theeconomy/2019/september/construction-costs-housing-bubble-driving-housing-prices-higher 53 See e.g. Guignet, Dennis, Matthew T. Heberling, Michael Papenfus,Olivia Griot, and Ben Holland. 2020.

Property values, water quality, and benefit transfer: A nationwide meta-analysis. Working Papers 20-04, Department of Economics, Appalachian State University. https://ideas.repec.org/p/apl/wpaper/20-

04.html

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compliance option, e.g., the mass-balance approach.54 The Order also largely prohibits the discharge of non-stormwater into and through the MS4 to receiving waters. While there are some limited exceptions where the non-stormwater discharge is expected not to be a source of pollutants, where the discharge is determined to be a source of pollutants it must be prohibited. The Order also supports efforts to maximize the capture of stormwater through retention basins, infiltration galleries, and other controls.
iii. Alternative 3, if implemented, would create heightened water quality related performance requirements for new developments and redevelopments that discharge to high quality water. Holding new developments and redevelopments to more stringent criteria may be practicable for some projects; however, the benefit to water quality is expected to be marginal as compared to the requirements already imposed on projects designated as “Priority Development Projects” in the Order. (See Part VIII.F.1.a of the Order.) Whenever feasible, these projects must implement structural BMPs to remove, reduce, beneficially reuse, and/or retain stormwater on-site. These structural BMPs must be designed to address the 85th percentile, 24-hour runoff volume. When onsite measures are technically infeasible (e.g., infill development), the projects are required to mitigate off-site. These requirements apply whether or not the receiving water is considered high-quality and are expected to improve water quality for a greater number of people.

Further, because waterbodies may be high quality for some pollutants and not others it is difficult, if not impossible, to designate specific areas as high quality waters.
iv. Both Alternatives 4 and 5, if implemented, could result in limited degradation of high quality water bodies. Any degradation that would occur under either alternative is consistent with the maximum benefit to the people of the state because the structural controls built through these programs will ultimately be more effective at maintaining and restoring water quality protective of beneficial uses than ongoing programmatic controls. The WMP permit terms of Alternatives 4 and 5 require implementation of objective technical solutions that have been demonstrated to be designed to meet water quality standards. Such controls necessarily take time to design and construct, but it is to the maximum benefit of the people of the state that such controls be designed and implemented properly so as to be protective of water quality in the long run. These measures that control impacts from stormwater and non-stormwater discharges in the Order are typically effective across multiple pollutants. The alternatives would concurrently address other constituents of concern that may not be causing impairment but may still be leading to degradation, resulting in improvements in levels of all pollutants, including those for which the receiving water may be high quality.
54 Where there are no applicable trash TMDLs, the Order requires compliance with the Statewide Trash Amendments in Priority Land Uses (PLU), alternative land use areas, and designated land use areas.

See, Part III.B (Trash Discharge Prohibitions), Order; and Part IV.B.3 (WQBELs for Trash), Order.

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v. Alternatives 4 and 5 avoid the high economic and social costs associated with decreased public services analyzed above in Parts III.H.2.b.i.(b)- (d)of this antidegradation analysis.55 At the same time, Alternatives 4 and 5 provide additional economic and social benefits to the people of the state by incentivizing and incorporating multi-benefit projects that include benefits beyond water quality protection such as increased local water supplies, beautified streets, plazas, and parking areas, and facilities that support habitat and recreation. For example, the MacArthur Lake Rehabilitation Project in the City of Los Angeles is projected to capture about 130 acre-feet of stormwater per year while improving the habitat and recreational value of the park by improving lake water quality and adding bioswales and wetlands. The master plan for the project was completed in 2017, and it is estimated that the project will be completed between 2024 to 2026.56
vi. Multi-benefit projects – that is, projects that fund stormwater capture that provide multiple benefits like those emphasized in WMPs – are actively encouraged by the State of California, which administers Proposition 1 funds ($200 million in grant funds) for such multi-benefit projects. For example, the Piru Stormwater Capture for Groundwater Recharge Project in Ventura County, which is estimated to capture about 17 acrefeet per year while also augmenting local water supply through groundwater recharge.57 Table F-19 provides further examples of multibenefit projects funded by Proposition 1, many of which were funded to build WMP projects in Los Angeles County. While Prop 1 funding has been expended, construction of multi-benefit projects from approved WMPs will likely qualify for these types of grant monies in the future.

Additionally, the construction of these projects also creates good-paying jobs that do not require advanced degrees, accessible to those in disadvantaged communities.58
55 See footnote nos. - and sources cited therein.
56 Deets, Deborah, Gilbert A. Cedillo, Enrique C. Zaldivar, and Shahram Kharaghani. 2020. MacArthur Lake Rehabilitation Project. PowerPoint presentation.
https://drive.google.com/file/d/1wOoTBkZE4amsEoOtwKOxxa_gAzSQISUu/view 57 Ventura County Public Works. 2020. In the News: Completed Project for Groundwater Recharge Captures Stormwater amid dry months of January and February. Ventura County Public Works. https://www.vcpublicworks.org/2020/08/25/piru-stormwater/ While Ventura County’s current 2010 MS4 Permit does not have provisions to implement WMPs as a compliance alternative, this project is included in the Ventura Countywide Municipal Stormwater Resource Plan prepared for the Ventura Countywide Stormwater Quality Management Program, dated September 20, 2016. This plan identifies projects that are expected to contribute towards meeting MS4 permit requirements, including TMDL-related provisions, in addition to achieving other benefits, including augmenting local water supplies. In this way, it has many similarities to WMPs. It is expected that these types of multi-benefit projects will be incentivized further by this Order, as they were in Los Angeles County following the issuance of the 2012 Los Angeles County MS4 Permit.
58 Building on the findings by Economic Roundtable, Los Angeles Alliance for a New Economy estimated that over 30 years, the Safe, Clean Water Program (Measure W) will create about 6,530 construction jobs and 1,347 O&M jobs, as well as about 1,559 annual indirect and induced jobs. This would yield about $14B in overall regional economic benefits from $9B in investment. Furthermore, many of these jobs created would be good-paying jobs that do not require an advanced degree, accessible to those in disadvantaged communities. (Los Angeles Alliance for a New Economy (LAANE). Liquid Assets. How Stormwater Infrastructure Builds Resilience, Health, Jobs, and Equity. March 2018.)

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Table F-19. Multi-benefit projects funded through Proposition 1 To Date Project Name Project
Proponent
Water
supply
benefit
Water quality
benefit
Flood
management
benefit
Environmental
benefit
Community
benefit
Benefit to
DAC
South Gate
Urban Orchard
Demonstration
Project
City of South
Gate
Increased
water supply
reliability
Nonpoint source
pollution control -- --
Enhanced
and/or created
recreational
and public use
areas
Y - City of
South Gate
and
Thunderbird
Villa Mobile
Home Park
San Fernando
Regional Park
Project (Planning
only)
City of San
Fernando
Increased
water supply
reliability
--
Decreased
flood risk by
reducing runoff
rate and/or
volume
--
Enhanced
and/or created
recreational
and public use
areas / Public
education
--
Tujunga
Spreading
Grounds
Enhancement
Project
City of Los
Angeles DWP
Increased
water supply
reliability
Reestablished
natural water
drainage and
treatment
Decreased
flood risk by
reducing runoff
rate and/or
volume
-- --
Y - The
communities
of Arleta and
Sun Valley
Central-Jefferson
High Green Alley
Network Storm
Water Capture
Project
The Trust for
Public and
City of Los
Angeles
Increased
water capture
and
conservation
Increased
filtration and
treatment of
runoff
-- --
Enhanced
and/or created
recreational
and public use
areas
Y - South Los
Angeles
John Anson Ford
Park Infiltration
Cistern
Gateway
Water
Management
Authority
Increased
water supply
reliability
Reestablished
natural water
drainage and
treatment
Decreased
flood risk by
reducing runoff
rate and/or
volume
-- --
Y - Cities of
Bell Gardens
and
Commerce

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ATTACHMENT F – FACT SHEET F-82
Project Name Project
Proponent
Water
supply
benefit
Water quality
benefit
Flood
management
benefit
Environmental
benefit
Community
benefit
Benefit to
DAC
Ladera Park
Stormwater
Capture Project
LA County
Increased
water supply
reliability
Reestablished
natural water
drainage and
treatment
--
Environmental
and habitat
protection and
improvement
-- N
Gates Canyon
Park Project LA County
Increased
water
conservation
Nonpoint source
pollution control --
Environmental
and habitat
protection and
improvement
-- N
East Los
Angeles
Sustainable
Median
Stormwater
Capture Project
LA County
Increased
water supply
reliability
Nonpoint source
pollution control -- --
Enhanced
and/or created
recreational
and public use
areas
Y - East Los
Angeles
Walnut Storm
Water Capture
and
Groundwater
Replenishment
Basin
City of
Torrance
Increased
water supply
reliability
Nonpoint source
pollution control
Decreased
flood risk by
reducing runoff
rate and/or
volume
--
Public
education Y
Piru Stormwater
Capture for
Groundwater
Recharge
Ventura
County
Increased
water supply
reliability
Increased
filtration and/or
treatment of
runoff
-- -- -- Y - Piru
Merced Avenue
Greenway
Improvement
Project
City of South
El Monte --
Increased
filtration and
treatment of
runoff
--
Reduced energy
use, greenhouse
gas emissions, or
provides a carbon
sink
Improved
public health
Y - City of
South El
Monte

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Project Name Project
Proponent
Water
supply
benefit
Water quality
benefit
Flood
management
benefit
Environmental
benefit
Community
benefit
Benefit to
DAC
Walnut Park
Pocket Park and
Stormwater
Infiltration
Project
LA County
Increased
water
conservation
Increased
filtration and
treatment of
runoff
Decreased
flood risk -- --
Y - Huntington
Park
Stormwater
Harvesting &
Treatment
Project For
Groundwater
Injection
City of Santa
Monica
Increased
water supply
reliability
Nonpoint source
pollution control
/ Increased
filtration and
treatment of
runoff
-- -- -- N
Alondra Park
Multi-Benefit
Stormwater
Capture Park
LA County Increased
water supply
Increased
filtration and
treatment of
runoff
-- --
Enhanced
and/or created
recreational
and public use
areas
N
Valley Village
Park Stormwater
Capture Project
City of Los
Angeles DWP
Increased
water supply
reliability
Increased
filtration and
treatment of
runoff
-- --
Enhanced
and/or created
recreational
and public use
areas
--

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vii. Alternative 4 is nevertheless not to the maximum benefit of the people of the state because it is less likely than Alternative 5 to result in the anticipated economic and social development described in Part III.H.2.b, subsection v, immediately above. As many of the permittees testified during the hearing on this Order, WMPs with the broader deemed compliance option (Alternative 5) better incentivize building and investing in long-term structural and non-structural controls that will improve water quality in the long run for multiple constituents and with multiple benefits.59 There are several reasons for this. Deeming Permittees in compliance with receiving water limitations while they are building and investing in these multi-benefit projects is necessary to accommodate the public bidding process (which many municipalities must go through to initiate construction) and the construction process, which takes approximately 5-7 years.60 Deeming Permittees in compliance while they are implementing their WMP projects allows Permittees to focus on constructing multi-benefit projects and long-term water sustainability planning, instead of focusing immediately (and spending money) on fixing violations or defending litigation related to those violations that might occur before their projects are completed. Having determined that water quality is most effectively protected by requiring Permittees to take a thoughtful proactive watershed management approach to discharges, which also encourages water supply augmentation and has environmental benefits, the Los Angeles Water Board finds that fairness and good public policy also advises against requiring them to comply with all effluent and receiving water limitations immediately (and potentially penalizing them for not doing so). The Order is designed to facilitate cooperation and coordination between the State and Permittees, local government entities. For example, Paul Alva, Principal Engineer for the Los Angeles County Department of Public Works, testified on July 16, 2021, that the 2012 Los Angeles County MS4 Permit structure, with deemed in compliance, has enabled the County to form new partnerships with entities like Caltrans and Los Angeles Department of Water and Power, and that it has fostered collaboration with other permittees as well. Allowing local governments to be deemed in compliance while implementing and constructing WMP projects strengthens this important public policy goal. Without the deemed compliance approach, Permittees are expected to shift at least some of their limited resources budgeted for planned, comprehensive, long-term, multi-benefit projects, to measures that are reactive, short-term, and ultimately less effective or protective of water quality in the long run.61 Importantly, the deemed compliance approach does not mean that the Los Angeles Water Board cannot take 59 See, Table F-20. Testimony from Los Angeles County Department of Public Works staff, and representatives from the Lower Los Angeles River Watershed and Lower San Gabriel River Watershed E/WMP groups on July 16, 2021 also supports this.
60 Testimony provided by Los Angeles County Public Works staff and other permittees at Board meetings and workshops in 2020 states that TMDL implementation projects (incorporated into WMPs) can take from five to seven years per project from design to completion (January 7, 2020 workshop and May 14, 2020 Board meeting).
61 See, footnote nos. - and citations therein.

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enforcement to ensure implementation of the Order requirements. Of course, Permittees are required to be pursuing and implementing their WMP controls as expeditiously as possible according to approved time schedules, and they can be separately subject to enforcement if they are not. Similarly, they may be subject to third-party citizen suits for violations of these terms.
viii. Alternative 5 is necessary to accommodate important economic and social development and to the maximum benefit of the people of the state because coupling the WMP framework with deemed compliance also incentivizes collaboration to implement the most cost-effective controls.

For example, Permittees in the County of Los Angeles were able to leverage the water supply and water quality benefits of the WMPs with deemed in compliance benefits to pass funding measures such as Measure W and Measure CW. Table F-20 documents the Measure W projects funded in 2020 and 2021,
62 the majority of which were also
proposed in an E/WMP. Table F-20 also documents another important fact that also demonstrates that Alternative 5 results in social and economic development that would not be achieved under Alternative 4.

The kinds of projects built under the WMP framework with deemed in compliance has facilitated investment and construction of multi-benefit projects that include parks, infiltration, and low impact development (among other things) in communities that might not have seen that investment without the Board’s adoption of the Los Angeles County MS4 Permit in 2012 incorporating the alternative compliance pathway of WMPs with deemed in compliance. This is not speculation. Mr. Alva from the County of Los Angeles explained to the Board on July 16, 2021, that the landscape of water quality has and will continue to vastly improve all over the County, and not just in certain communities, due to WMP construction and implementation. Under the 2001 Permit, which did not include deemed in compliance provisions for RWLs, only about two dozen coastal projects for low flow diversions were built to achieve water quality objectives. The 2012 Permit facilitated a shift in the building of projects from the limited number of coastal projects under the 2001 permit, to the planning, approval and beginning construction of many multi-benefit projects all over the County, including in disadvantaged, inland communities. All of Los Angeles County benefits from the multibenefit projects now – which include multi-benefit projects and naturebased solutions that take into account current pressing challenges of drought and climate change and allow change to occur in an equitable fashion, in communities where they would not have occurred otherwise.

Mr. Alva testified that this paradigm shift, towards building multi-benefit projects across the region and not just at the coast, would not have happened without the current compliance pathway, WMPs with deemed in compliance. Alternative 5, compared to Alternative 4, has thus already resulted in and is expected to continue to result in important economic and social development and are to the maximum benefit to the people of the state.
62 Los Angeles County. Safe Clean Water Program – 2020-21 Stormwater Investment Plans for nine Watershed Area Steering Committees. https://safecleanwaterla.org/projects2/

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Table F-20. Measure W Funded Projects (2020-2021)
Project NameProject DeveloperProject TypeWatershed Area WMP/EWMP Area
Proposed inE/WMP?DAC?Natural BasedSolutionWater SupplyCommunity BenefitsPrimary Pollutant Addressed Active
Transportation
Rail toRiver
Corridor
Project ‐
Segment A
Los Angeles
Metropolitan
Transit
Authority
(Metro)
LID Upper Los
Angeles
River
ULAR No YesMimic Natural
Processes/Uses
Natural Material
Connect to
Aquifer/Use
Onsite
Reduce Heat Island/
Provide Recreational
Opportunities/
ProvideShade/
Improve Flood
Protection/ Improve
Waterway Access/
Enhance Habitat or
Park Space/
Enhance Green
Space in Schools
Bacteria
Adventure
Park Multi
Benefit
Stormwater
Capture
Project
Los Angeles
County
Public
Works
Capture
and
diversion
to sewer;
LID
Upper
San
Gabriel
River
USGR Yes YesMimic Natural
Processes/ Uses
Natural Material
Connect to
WWTP
Reduce Heat
Island/Provide
Recreational
Opportunities/
ProvideShade/
Improve Flood
Protection/ Enhance
Habitat or ParkSpace
Other
Alondra Park
Multi Benefit
Stormwater
Capture
Project
Los Angeles
County
Capture
and
diversion
to sewer;
LID
South
Santa
MonicaBay
DC Yes YesMimic Natural
Processes/ Uses
Natural Material
Connect to
Aquifer/Connect
toWWTP
Reduce Heat
Island/Provide
Recreational
Opportunities/
ProvideShade/
Improve Flood
Other

EXHIBIT A
Tuesday, October 07, 2025 Reg CC MTG, Page *452
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ATTACHMENT F – FACT SHEET F-87
Project NameProject DeveloperProject TypeWatershed Area WMP/EWMP Area
Proposed inE/WMP?DAC?Natural BasedSolutionWater SupplyCommunity BenefitsPrimary Pollutant Addressed Protection/Enhance
Habitat or ParkSpace
Baldwin Lake
and Tule
Pond
Restoration
Project
Los Angeles
County Public
Works/Flood
Control
District
EnhancementRio Hondo RH‐
SGR
Yes YesMimic Natural
Processes/Uses
Natural Material
Connect to
Aquifer
Provide
Recreational
Opportunities/
Improve Flood
Protection/
Improve Waterway
Access/ Enhance
Habitat or Park
Space
Other
Barnes Park City of Baldwin
Park
Infiltration Upper
San
Gabriel
River
USGR Yes YesMimic Natural
Processes/ Uses
Natural Material
-- Reduce Heat Island/
Provide Recreational
Opportunities/
ProvideShade/
Improve Flood
Protection/ Enhance
Habitat or ParkSpace
Zn
Bassett High
School
Stormwater
Capture
Multi‐Benefit
Project
Los Angeles
County
Infiltration Upper
San
Gabriel
River
USGR Yes*YesMimic Natural
Processes/ Uses
Natural Material
Connect to
Aquifer
Reduce Heat Island/
Provide Recreational
Opportunities/
ProvideShade/
Improve Flood
Protection/ Enhance
Zn

EXHIBIT A
Tuesday, October 07, 2025 Reg CC MTG, Page *453
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ATTACHMENT F – FACT SHEET F-88
Project NameProject DeveloperProject TypeWatershed Area WMP/EWMP Area
Proposed inE/WMP?DAC?Natural BasedSolutionWater SupplyCommunity BenefitsPrimary Pollutant Addressed Habitat or Park
Space/Enhance
Green Space in
Schools
Beverly Hills
Burton Way
Green Street
and Water
Efficient
Landscape
Project
City of
Beverly Hills
(Derek
Nguyen)
Green
Street/
Infiltration
Central
Santa
Monica
Bay
Ballona
Creek
No No Mimic Natural
Processes/ Uses
Natural Material
Connect to
Aquifer/Use
Onsite
Reduce Heat Island/
Provide Shade/
Improve Flood
Protection/ Enhance
Habitat or Park
Space
Zn
Bolivar Park City of
Lakewood
O&M Lower
San
Gabriel
River
LCC Yes YesUses Natural
Material
Connect to
Aquifer/ Use
Onsite
Reduce Heat Island/
Provide Recreational
Opportunities/
ProvideShade/
Enhance Habitat or
Park Space/
Enhance Green
Space in Schools
Zn
Caruthers Park City of
Bellflower
O&M Lower
San
Gabriel
River
LCC Yes YesMimic Natural
Processes/
Uses Natural
Material
Connect to
Aquifer/ Use
Onsite
Reduce Heat
Island/Provide
Recreational
Opportunities/Provide
Shade/Improve Flood
Protection/Enhance
Other

EXHIBIT A
Tuesday, October 07, 2025 Reg CC MTG, Page *454
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ATTACHMENT F – FACT SHEET F-89
Project NameProject DeveloperProject TypeWatershed Area WMP/EWMP Area
Proposed inE/WMP?DAC?Natural BasedSolutionWater SupplyCommunity BenefitsPrimary Pollutant Addressed Habitat or Park
Space
City of San
Fernando
Regional Park
Infiltration
Project
City of San
Fernando
(Kenneth Jones)
Infiltration Upper Los
Angeles
River
ULAR Yes YesMimic Natural
Processes
Connect to
Aquifer
Provide Shade/
Improve Flood
Protection/ Enhance
Habitat or Park
Space
Zn
Culver City
Mesmer Low
Flow
City of Culver
City
Low Flow
Diversion
Central
Santa
Ballona
Creek
Yes No -- Connect to
WWTP
-- Other
East Los
Angeles
Sustainable
Median
Stormwater
Capture Project
Los Angeles
County
Infiltration; LIDRio Hondo ULAR Yes* Yes Mimic Natural
Processes/
Uses Natural
Material
Connect to
Aquifer
Reduce Heat Island/
Provide Recreational
Opportunities/ Provide
Shade/ Improve Flood
Protection/ Enhance
Habitat or Park Space
Other
Echo Park Lake
Rehabilitation
City of Los
Angeles, Bureau
of Sanitation
O&M Upper Los
Angeles
River
ULAR No No Mimic Natural
Processes
/Uses Natural
Material
Use Onsite Provide Recreational
Opportunities/
Improve Flood
Protection/ Enhance
Habitat or Park Space
Nitrogen

EXHIBIT A
Tuesday, October 07, 2025 Reg CC MTG, Page *455
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ATTACHMENT F – FACT SHEET F-90
Project NameProject DeveloperProject TypeWatershed Area WMP/EWMP Area
Proposed inE/WMP?DAC?Natural BasedSolutionWater SupplyCommunity BenefitsPrimary Pollutant Addressed El Dorado
Regional Project
City of Long
Beach
Planning and
Design
Lower
San
Gabriel
River
LSGR No Yes Mimic Natural
Processes
/Uses Natural
Material
Connect to
WWTP /Use
Onsite
Reduce Heat Island/
Provide Recreational
Opportunities/ Provide
Shade/ Improve Flood
Protection/ Improve
Waterway Access/
Enhance Habitat or
Park Space
Zn
Encanto Park
Stormwater
Capture Project
City of Monrovia Infiltration Upper
San
Gabriel
River
RHSGRYes Yes Mimic Natural
Processes/
Uses Natural
Material
Connect to
Aquifer
Reduce Heat Island/
Provide Shade/
Improve Flood
Protection/ Enhance
Habitat or Park Space
Zn
Fernangeles
Park Stormwater
Capture Project
Los Angeles
Department of
Water and
Power (LADWP)
Infiltration Upper Los
Angeles
River
ULAR Yes* Yes Mimic Natural
Processes/
Uses Natural
Material
Connect to
Aquifer
Reduce Heat Island/
Provide Recreational
Opportunities/ Provide
Shade/ Improve Flood
Protection/ Improve
Waterway Access/
Enhance Habitat or
Park Space
Zn
Franklin D.

Roosevelt Park
Regional
Stormwater
Capture Project
Los Angeles
County
Infiltration Upper Los
Angeles
River
ULAR Yes Yes Mimic Natural
Processes/
Uses Natural
Material
Connect to
Aquifer
Reduce Heat Island/
Provide Recreational
Opportunities/ Provide
Shade/ Improve Flood
Protection/ Enhance
Zn

EXHIBIT A
Tuesday, October 07, 2025 Reg CC MTG, Page *456
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ATTACHMENT F – FACT SHEET F-91
Project NameProject DeveloperProject TypeWatershed Area WMP/EWMP Area
Proposed inE/WMP?DAC?Natural BasedSolutionWater SupplyCommunity BenefitsPrimary Pollutant Addressed Habitat or Park Space
Garvey Avenue
Grade
Separation
Drainage
Improvement
Project
City of El Monte Infiltration Upper
San
Gabriel
River
El
Monte
Yes* Yes Mimic Natural
Processes
Connect to
Aquifer
Improve Flood
Protection
Zn
Hasley Canyon
Park Stormwater
Improvements
Project
Los Angeles
County Public
Works
Infiltration Santa
Clara
River
USCR Yes No Mimic Natural
Processes/
Uses Natural
Material
Connect to
Aquifer
Provide Recreational
Opportunities/
Improve Flood
Protection/ Enhance
Habitat or Park Space
Nitrogen
Hermosillo Park City of Norwalk Infiltration Lower
San
Gabriel
River
LSGR Yes* Yes Mimic Natural
Processes/
Uses Natural
Material
Connect to
Aquifer/Use
Onsite
Reduce Heat Island/
Provide Recreational
Opportunities/ Provide
Shade/ Improve Flood
Protection/ Enhance
Habitat or Park Space
Zn
John Anson
Ford Park
Infiltration
Cistern
City of Bell
Gardens
Infiltration Lower Los
Angeles
River
LARUR2Yes Yes Mimic Natural
Processes/
Uses Natural
Material
Connect to
Aquifer
Reduce Heat Island/
Provide Recreational
Opportunities/ Provide
Shade/ Improve Flood
Zn

EXHIBIT A
Tuesday, October 07, 2025 Reg CC MTG, Page *457
MS4 DISCHARGES WITHIN THE ORDER NO. R4-2021-0105
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ATTACHMENT F – FACT SHEET F-92
Project NameProject DeveloperProject TypeWatershed Area WMP/EWMP Area
Proposed inE/WMP?DAC?Natural BasedSolutionWater SupplyCommunity BenefitsPrimary Pollutant Addressed Protection/ Improve
Waterway Access/
Enhance Habitat or
Park Space
Ladera Park
Stormwater
Improvements
Project
Los Angeles
County Public
Works
Infiltration
Wells
Central
Santa
Monica
Bay
Ballona
Creek
Yes No Mimic Natural
Processes/
Uses Natural
Material
Connect to
Aquifer/ Use
Onsite
Reduce Heat Island/
Provide Recreational
Opportunities/ Provide
Shade/ Enhance
Habitat or Park Space
Zn
Lankershim
Boulevard Local
Area Urban
Flow
Management
Network Project
City of Los
Angeles, Bureau
of Sanitation
Infiltration Upper Los
Angeles
River
ULAR Yes* Yes Mimic Natural
Processes/
Uses Natural
Material
Connect to
Aquifer
Reduce Heat Island/
Provide Shade/
Improve Flood
Protection
Zn
Long Beach
Municipal Urban
Stormwater
Treatment (LB
MUST) - Phase
1 City of Long
Beach
Treatment
and reuse
Lower Los
Angeles
River
LLAR Yes Yes Mimic Natural
Processes/
Uses Natural
Material
Use Onsite Reduce Heat Island/
Provide Recreational
Opportunities/ Provide
Shade/ Improve Flood
Protection/ Improve
Waterway Access/
Enhance Habitat or
Park Space
Other

EXHIBIT A
Tuesday, October 07, 2025 Reg CC MTG, Page *458
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ATTACHMENT F – FACT SHEET F-93
Project NameProject DeveloperProject TypeWatershed Area WMP/EWMP Area
Proposed inE/WMP?DAC?Natural BasedSolutionWater SupplyCommunity BenefitsPrimary Pollutant Addressed MacArthur Lake
Rehabilitation
Project
City of Los
Angeles, Bureau
of Sanitation
Capture and
reuse;
Recreation
enhancement
Central
Santa
Monica
Bay
Ballona
Creek
Yes Yes Mimic Natural
Processes/
Uses Natural
Material
Connect to
WWTP/ Use
Onsite
Reduce Heat Island/
Provide Recreational
Opportunities/ Provide
Shade/ Improve Flood
Protection/ Enhance
Habitat or Park Space/
Enhance Green
Space in Schools
Zn
Mayfair Park City of
Lakewood
O&M Lower
San
Gabriel
River
LCC Yes Yes Mimic Natural
Processes/
Uses Natural
Material
Connect to
WWTP/ Use
Onsite
Reduce Heat Island/
Provide Recreational
Opportunities/ Provide
Shade/ Enhance
Habitat or Park Space
Other
Monteith Park
and View Park
Green Alley
Stormwater
Improvements
Project
Los Angeles
County Public
Works
Infiltration
Wells
Central
Santa
Monica
Bay
Ballona
Creek
No Yes Mimic Natural
Processes/
Uses Natural
Material
-- Reduce Heat Island/
Provide Recreational
Opportunities/ Provide
Shade/ Enhance
Habitat or Park Space
Zn
Newhall Park
Infiltration
Dan Duncan,
Oliver Cramer
Infiltration Santa
Clara
River
USCR Yes Yes Mimic Natural
Processes/
Uses Natural
Material
Connect to
Aquifer
Provide Recreational
Opportunities/ Provide
Shade/ Improve Flood
Protection/ Enhance
Habitat or Park Space/
Enhance Green
Space in Schools
Bacteria

EXHIBIT A
Tuesday, October 07, 2025 Reg CC MTG, Page *459
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ATTACHMENT F – FACT SHEET F-94
Project NameProject DeveloperProject TypeWatershed Area WMP/EWMP Area
Proposed inE/WMP?DAC?Natural BasedSolutionWater SupplyCommunity BenefitsPrimary Pollutant Addressed Oro Vista Local
Area Urban
Flow
Management
Project
City of Los
Angeles, Bureau
of Sanitation
Infiltration; LIDUpper Los
Angeles
River
ULAR Yes* No Mimic Natural
Processes/
Uses Natural
Material
Connect to
Aquifer
Reduce Heat Island/
Provide Shade/
Improve Flood
Protection
Zn
Pedley
Spreading
Grounds
East San
Gabriel Valley
Watershed
Management
Group (City of
San Dimas, City
of Claremont,
City of Pomona,
City of La
Verne)
Infiltration Upper
San
Gabriel
River
ESGV No No Mimic Natural
Processes
Connect to
Aquifer
Improve Flood
Protection/ Enhance
Habitat or Park Space
Other
Rory M. Shaw
Wetlands Park
Project
Los Angeles
Flood Control
District
Detention
pond/
infiltration
Upper Los
Angeles
River
ULAR Yes* Yes Mimic Natural
Processes/
Uses Natural
Material
Connect to
Aquifer
Reduce Heat Island/
Provide Recreational
Opportunities/ Provide
Shade/ Improve Flood
Protection/ Improve
Waterway Access/
Enhance Habitat or
Park Space
Nitrogen

EXHIBIT A
Tuesday, October 07, 2025 Reg CC MTG, Page *460
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ATTACHMENT F – FACT SHEET F-95
Project NameProject DeveloperProject TypeWatershed Area WMP/EWMP Area
Proposed inE/WMP?DAC?Natural BasedSolutionWater SupplyCommunity BenefitsPrimary Pollutant Addressed Skylinks Golf
Course at
Wardlow
Stormwater
Capture Project
City of Long
Beach
Infiltration Lower
San
Gabriel
River
LCC Yes No Mimic Natural
Processes/
Uses Natural
Material
Connect to
Aquifer/ Use
Onsite
Reduce Heat Island/
Provide Recreational
Opportunities/ Provide
Shade/ Improve Flood
Protection/ Improve
Waterway Access/
Enhance Habitat or
Park Space
Zn
Strathern Park
North
Stormwater
Capture Project
Los Angeles
Department of
Water and
Power (LADWP)
Infiltration Upper Los
Angeles
River
ULAR Yes* Yes Mimic Natural
Processes/
Uses Natural
Material
Connect to
Aquifer
Reduce Heat Island/
Provide Recreational
Opportunities/ Provide
Shade/Improve Flood
Protection/ Improve
Waterway Access/
Enhance Habitat or
Park Space
Zn
Sustainable
Water
Infrastructure
Project
City of Santa
Monica
Capture,
advance
treatment, and
reuse
Central
Santa
Monica
Bay
SMB
J2-J3
Yes Yes Mimic Natural
Processes/
Uses Natural
Material
Connect to
Aquifer/
Connect to
WWTP/ Use
Onsite
Reduce Heat Island/
Provide Recreational
Opportunities/ Provide
Shade/ Improve Flood
Protection/ Improve
Waterway Access/
Enhance Habitat or
Park Space/ Enhance
Green Space in
Schools
Bacteria

EXHIBIT A
Tuesday, October 07, 2025 Reg CC MTG, Page *461
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ATTACHMENT F – FACT SHEET F-96
Project NameProject DeveloperProject TypeWatershed Area WMP/EWMP Area
Proposed inE/WMP?DAC?Natural BasedSolutionWater SupplyCommunity BenefitsPrimary Pollutant Addressed The Distributed
Drywell System
Project
City of Glendale Infiltration Upper Los
Angeles
River
ULAR Yes Yes Mimic Natural
Processes/
Uses Natural
Material
Connect to
Aquifer
Reduce Heat Island/
Provide Shade/
Improve Flood
Protection
Zn
Torrance Airport
Storm Water
Basin Project,
Phase 2
City of Torrance Capture and
divert to
sanitary sewer
South
Santa
Monica
Bay
Beach
Cities
Yes Yes -- Connect to
WWTP
Improve Flood
Protection
Other
Valley Village
Park Stormwater
Capture Project
Los Angeles
Department of
Water and
Power (LADWP)
Infiltration Upper Los
Angeles
River
ULAR Yes Yes Mimic Natural
Processes/
Uses Natural
Material
Connect to
Aquifer
Reduce Heat Island/
Provide Recreational
Opportunities/ Provide
Shade/ Improve Flood
Protection/ Improve
Waterway Access/
Enhance Habitat or
Park Space
Other
Walnut Park
Pocket Park
Project
County of Los
Angeles
Infiltration Upper Los
Angeles
River
ULAR Yes* Yes Mimic Natural
Processes/Uses
Natural Material
Connect to
Aquifer
Reduce Heat Island/
Provide Recreational
Opportunities/ Provide
Shade/ Enhance
Habitat or Park Space
Zn

EXHIBIT A
Tuesday, October 07, 2025 Reg CC MTG, Page *462
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ATTACHMENT F – FACT SHEET F-97
Project NameProject DeveloperProject TypeWatershed Area WMP/EWMP Area
Proposed inE/WMP?DAC?Natural BasedSolutionWater SupplyCommunity BenefitsPrimary Pollutant Addressed Washington
Boulevard
Stormwater and
Urban Runoff
Diversion
City of Culver
City
Capture and
divert to
sanitary sewer
Central
Santa
Monica
Bay
MdR Yes No Mimic Natural
Processes/
Uses Natural
Material
Connect to
WWTP/ Use
Onsite
Reduce Heat Island/
Provide Recreational
Opportunities/ Provide
Shade/ Improve Flood
Protection
Other
Wilmington Q
Street Local
Urban Area
Flow
Management
Project
City of Los
Angeles, Bureau
of Sanitation
Green Street/
Infiltration
South
Santa
Monica
Bay
DC Yes* Yes Mimic Natural
Processes/Uses
Natural Material
-- Reduce Heat Island/
Provide Shade/
Improve Flood
Protection/ Enhance
Green Space in
Schools
Zn
Wingate Park
Regional EWMP
Project
City of Covina Planning and
design of
Infiltration
project
Upper
San
Gabriel
River
USGR Yes Yes Mimic Natural
Processes/
Uses Natural
Material
Connect to
Aquifer
Reduce Heat Island/
Provide Recreational
Opportunities/ Provide
Shade/ Improve Flood
Protection/ Improve
Waterway Access/
Enhance Habitat or
Park Space
Zn
* This specific project was not identified in the E/WMP, but this type of project was identified.

EXHIBIT A
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ATTACHMENT F – FACT SHEET F-98
Similarly, Permittees in both Los Angeles and Ventura Counties have been able to utilize Proposition 1 funding to develop multi-benefit stormwater management projects such as those set forth in Table F-20, supra, which are exactly the type of projects that WMPs contemplate.63 And, as discussed immediately above, this alternative provides important socioeconomic benefits such as creation of new jobs, increased local water supplies, beautified streets, plazas, and parking areas, and facilities that support habitat and recreation, while allowing the local governments to maintain important public services. This alternative therefore has the greatest chance of success, within the shortest time frame, and furthers the goal of maintaining and achieving water quality standards.
ix. Further, Alternative 5 does not create a framework where there is a deemed in compliance pathway for all receiving water limitations.

Alternative 5 does not relieve Permittees of the requirement to effectively prohibit non-stormwater discharges. The non-stormwater discharge prohibitions are not afforded deemed compliance status through the WMP provisions. Rather, the WMPs provide alternative compliance pathways only for particular waterbody-pollutant combinations: Those addressed by TMDLs (highest priority); those that are listed on the Clean Water Act Section 303(d) List as impaired and for which MS4 discharges may be causing or contributing to the impairment (high priority); or for which there are insufficient data to indicate water quality impairment in the receiving water according to the State’s Listing Policy, but which exceed applicable receiving water limitations contained in this Order and for which MS4 discharges may be causing or contributing to the exceedance within the last five years (medium priority).64 None of these water bodies are high quality waters currently. As explained in State Water Board Order WQ 2020-0038, Permittees must be clear about which waterbody-pollutant combinations and receiving water limitations they will address in their WMPs.65 “Deemed compliance is not a right; it is an accommodation based on the time and effort required to undertake the complex planning and implementation efforts needed to improve water quality. It is meant to encourage significant investment in collaborative regional - and watershed-based BMP implementation, leading eventually to all receiving waters meeting final receiving water limitations.”66
63 See, Table F-21, supra.
64 As such, many of the waters to which the deemed in compliance allowance provisions will be applied are not high quality waters in the first place (see Order, Part IX.A.4; IX.B.1-3) and subject instead to the antidegradation analysis under Part III.H.1 of this Fact Sheet. The findings above are made only to the extent these waterbodies are considered high quality based on a historic baseline. To the extent that the WMP alternative compliance pathways do allow for pollutants to be discharged into otherwise high quality waters, the period to achieve receiving water limitations where there are exceedances must be as short as possible.
65 See, e.g., WQ 2020-0038 at p. 11.
66 WQ 2020-0038 at p. 10.

EXHIBIT A
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ATTACHMENT F – FACT SHEET F-99
x. Alternative 5 may result in limited degradation of high quality waters, in particular currently impaired waters that may nevertheless be considered high quality waters based on a historic baseline.67 The federal antidegradation policy does not require consideration of economic and social costs associated with degradation; it only requires findings that “allowing lower water quality is necessary to accommodate important economic or social development in the area in which the waters are located.” The state antidegradation policy does not define the exact factors that must be considered in determining “maximum benefit to the people of the state.” APU 90-004 states that factors to be considered in a complete antidegradation analysis include economic and social costs of the discharge compared to its benefits, but this Order is subject only to a simple antidegradation analysis.68 The Los Angeles Water Board has nevertheless considered the costs associated with water quality degradation that may occur under Alternative 5, but has done so necessarily at a generalized level. Specifically, in choosing Alternative 5 over Alternative 4, the Los Angeles Water Board finds as follows:
(a) There are significant environmental, public health, and economic costs associated with exceedances of water quality objectives.

Southern California’s local economy thrives on a healthy environment, as does the health of its population. By way of example, the failure to control stormwater runoff (which would result in exceedances of water quality objectives) would, among other things, negatively impact ocean water quality, which would negatively impact the coastal economy, including tourism and the fishing industry. Similarly, the failure to meet water quality objectives in ocean waters would negatively impact recreation and public health of beachgoers. These costs are discussed in detail in Part XIII.D.4 of this Fact Sheet and are incorporated into these findings by reference.
(b) The considered costs are associated with exceedances of water quality objectives rather than limited degradation of high quality waters to a level that remains better than objectives. This is because the objectives are set to protect beneficial uses in the first place. (c) Where Alternative 5 may allow a currently high quality waterbody to degrade below water quality objectives, or where it will allow a currently impaired, but historically high quality waterbody to stagnate or worsen in quality, even for multiple years, this allowance is for a finite period of time defined by the compliance schedule specified in the permit. The Los Angeles Water Board finds that the temporary degradation is justified based on the social and economic benefits discussed in findings Part III.H.2.b of this Fact Sheet. 67 The WMPs are designed to provide deemed in compliance only for pollutants for which the waterbody is impaired or there are exceedances of receiving water limitations and the Order is not written to allow currently high quality waterbodies to be degraded for those pollutants for which deemed compliance is not provided.
68 Outside of the complete antidegradation analysis context, APU 90-004 states only that the “findings should indicate . . . [t]he socioeconomic and public benefits that result from lowered water quality.” (APU 90-004, p. 1.)

EXHIBIT A
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ATTACHMENT F – FACT SHEET F-100
associated with Alternative 5, notwithstanding the potential costs of degradation. In particular, the Los Angeles Water Board anticipates that the structural controls that are designed and built over a longer timeframe are more likely to lead to water quality improvements than other measures.
(d) Alternative 4 could potentially avoid some of the costs discussed in subsection (a), above, because some Permittees may correct some exceedances earlier if required to comply immediately with receiving water limitations. From a practical perspective, however, the Los Angeles Water Board finds that immediate compliance, particularly for those waters that may have been high quality historically but are not high quality currently, is unrealistic even if required, given the technical and financial constraints faced by Permittees. Since Permittees will not be able to afford to comply immediately, any costs avoided would be minimal.69
xi. Regarding Alternative 6, WQBELs are for the most part set to be protective of beneficial uses, which is the floor of the level of protection required under the antidegradation policies and may not be protective of water quality higher than necessary to protect beneficial uses. Therefore, this alternative is not more protective of high quality water bodies than requiring compliance with receiving water limitations, which already require permittees’ MS4 discharges to not cause or contribute to exceedances of water quality objectives. This alternative would impose a significant analytical hurdle on development and adoption of a permit by requiring the Los Angeles Water Board to spend extensive efforts to analyze hundreds of thousands of waterbody-pollutant combinations and then further conduct an infeasible set of reasonable potential analyses to determine whether the permittees’ discharges are impacting high quality waters and for what pollutants. Ultimately, the alternative would divert staff resources from oversight of the implementation of potentially more effective and practical permit requirements, as well diverting staff from the Board’s other programs.
xii. For all of the reasons set forth above, the Los Angeles Water Board finds that any lowering of high quality waters under this Order’s structure, which is consistent with Alternative 5 and components of Alternatives 1 and 2, is necessary to accommodate important economic or social development in the Region and is to the maximum benefit of the people of the State.
c. Requirement for Highest Statutory and Regulatory Requirements and Best Practicable Treatment and Control: The Order requires the highest statutory 69 See, e.g., Testimony from Arne Anselm, Ventura County, Transcript, October 15, 2020 Board Workshop, at p. 55:12-14 (“And certainly funding plays a big part of that, and getting a funding plan together, and developing that source of money. It’s hard to do everything without that money. If we’re limited to just the funds we have, not much will get done.”); Chris Minton, Larry Walker and Associates, on behalf of the Malibu Creek Watershed EWMP Group, Transcript, February 11, 2021 Board Meeting, at p. 83:8-14 (“One reason we asked for more time is that it does take money to build projects. Under no cashflow scenario is it possible for us to receive or borrow enough money in the next five years to cover the cost of all of our projects. Even if our EWMP cost estimates are off by 50-percent, we still won't receive enough funds.”). See, also, references cited in footnote , supra.

EXHIBIT A
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ATTACHMENT F – FACT SHEET F-101
and regulatory requirements and requires that the Permittees meet best practicable treatment or control.
i. The Order prohibits all non-stormwater discharges, with a few enumerated exceptions, through the MS4 to all receiving waters. ii. As required by 40 CFR section 122.44(a), the Permittees must comply with the “maximum extent practicable” technology-based standard set forth in CWA section 402(p)(3)(B)(iii) and implement control measures under six program elements of a stormwater management program. iii. As required by CWA section 402(p)(3)(B)(iii) and 40 CFR section 122.44(d)(1)(vii)(B), the Permittees must comply with applicable WQBELs based on TMDL WLAs established for waters in the Los Angeles Region.
iv. The Order also contains provisions to encourage, wherever feasible, retention of stormwater from the 85th percentile, 24-hour storm event.

This stormwater retention design standard is based on robust engineering and technical evaluations to determine state-of-the-art design standards for post-construction site scale BMPs and catchment scale regional BMPs.70
v. The measures that control impacts from stormwater and non-stormwater discharges in the Order are typically effective across multiple pollutants.

For example, retention basins, low-impact development controls, and low flow diversions avert stormwater and non-stormwater from reaching the receiving water at all—preventing degradation to the receiving water from all types of constituents. The Watershed Management Program provisions contained in the Order are designed to achieve water quality standards for those constituents that are impairing the receiving water, as well as to address other constituents of concern that may not be causing impairment as defined in CWA section 303(d) and State policy.

The Watershed Management Programs developed pursuant to these provisions will likely result in improvements in levels of all pollutants, including those for which the receiving water may be high quality.

As a final backstop against degradation, the Order includes an extensive monitoring and reporting program, including concurrent monitoring of MS4 discharges at representative outfalls and in receiving waters for all pollutants of concern in the particular receiving water; monitoring during both wet weather and dry weather conditions; and analysis of toxicity in receiving waters and, if toxicity is observed, follow-up monitoring of MS4 discharges among other monitoring requirements. Monitoring data must be submitted semi-annually, and the Order also includes reopener provisions to allow modification of the Order as necessary to add preventative provisions if a threat of degradation is suspected. The monitoring and reporting requirements are sufficient to identify and address changes in water quality.71
70 See, for example, State Water Board Order WQ 2000-11, the “LA SUSMP Order” and Concept Development: Design Storm For Water Quality in the Los Angeles Region (SCCWRP, Technical Report 520, October 2007).
71 In AGUA, 210 Cal.App.4th 1255, the Court of Appeal held that a dairy general non-NPDES permit violated the State antidegradation policy in part because the permit relied on a prohibition of degradation to assert that the antidegradation policy was not implicated by the discharges without incorporating any additional

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ATTACHMENT F – FACT SHEET F-102
I. Anti-Backsliding Requirements
Sections 402(o) and 303(d)(4) of the CWA and federal regulations at 40 C.F.R. section 122.44(l) prohibit backsliding in NPDES permits. These anti-backsliding provisions require effluent limitations in a reissued permit to be as stringent as those in the previous permits, with some exceptions where limitations may be relaxed. In general, the effluent limitations in the Order are at least as stringent as the effluent limitations in Order No.

R4-2010-0108 (Ventura County), Order No. R4-2012-0175 (Los Angeles County), and Order No. R4-2014-0024 (Long Beach). However, certain of the effluent limitations in the Order are not identical to the effluent limitations in the previous MS4 permits because the Order implements revisions to TMDLs that occurred after these permits were adopted. Table F-21 lists changes to effluent limitations that increase allowable pollutant loadings or remove the effluent limitations entirely due to revised WLAs. While not all of the changes to these effluent limitations constitute backsliding, the rationale for each change is discussed below.

Table F-21. Changes to Effluent Limitations in Previous MS4 Permits TMDL Constituent Waterbody Existing
Limitation New Limitation
Revolon
Slough and
Beardsley
Wash Trash
TMDL
Trash Revolon Slough and
Beardsley Wash
0 Trash
discharged
from all land
uses
0 Trash discharged
from priority land
uses
Malibu
Creek
Watershed
Trash
TMDL
Trash Malibu Creek
Watershed
0 Trash
discharged
from all land
uses
0 Trash discharged
from priority land
uses
Ballona
Creek
Metals
TMDL
Selenium
Ballona Creek 169 g/day
None
Sepulveda Channel 76 g/day
Ballona Creek and
tributaries 5 μg/L
Ballona Creek and
tributaries

4.73 x 10-6 x
daily storm
volume (L)
g/day
Copper Ballona Creek 807.7 g/day 1,457.6 g/day
technical controls, or in lieu of such controls sufficient or appropriate monitoring to verify that in fact there was no ongoing degradation. The Order acknowledges that there may be some limited degradation of high quality waters due to stormwater and non-stormwater discharges, but imposes appropriate controls (e.g., through compliance with receiving water limitation provisions, discharge prohibitions, and WQBELs) to minimize any such degradation and further imposes extensive monitoring and reporting as described above to detect any degradation that may be inconsistent with the findings of the Order.

EXHIBIT A
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ATTACHMENT F – FACT SHEET F-103
TMDL Constituent Waterbody Existing
Limitation New Limitation
Sepulveda Channel 365.6 g/day 540.6 g/day
Ballona Creek and
tributaries 24 μg/L 35.56 μg/L
Ballona
Creek
Metals
TMDL
Lead
Ballona Creek 432.6 g/day 805.0 g/day
Sepulveda Channel 196.1 g/day 298.7 g/day
Ballona Creek and
tributaries 13 μg/L 19.65 μg/L
Ballona Creek and
tributaries

5.58 x 10-5 x
daily storm
volume (L)
g/day

7.265 x 10-5 x daily
storm volume (L)
g/day
Zinc
Ballona Creek 10,273.1 g/day 18,302.1 g/day
Sepulveda Channel 4,646.4 g/day 6,790.8 g/day
Ballona Creek and
tributaries 304 μg/L 446.55 μg/L
Ballona
Creek
Estuary
Toxic
Pollutants
TMDL
Total PAHs
Ballona Creek Estuary
26,900 g/yr None
Total
Chlordane 3.34 g/yr 8.69 g/yr
Total DDTs 10.56 g/yr 12.70 g/yr
Marina del
Rey Harbor
Toxic
Pollutants
TMDL
Copper
Marina del Rey Harbor

2.01 kg/yr 2.26 kg/yr
Lead 2.75 kg/yr 3.10 kg/yr
Zinc 8.85 kg/yr 9.96 kg/yr
Total
Chlordane 0.0295 g/yr 0.0332 g/yr
Total PCBs 1.34 g/yr 1.51 g/yr
Los
Angeles
River (LAR)
Metals
TMDL
Copper
LAR Reach 4 0.32 kg/day 1.27 kg/day
LAR Reach 3 0.06 kg/day 0.24 kg/day
LAR Reach 2 0.13 kg/day 0.52 kg/day
LAR Reach 1 0.14 kg/day 0.56 kg/day
Tujunga Wash 0.001 kg/day 0.008 kg/day
Burbank Western
Channel 0.15 kg/day 0.71 kg/day

EXHIBIT A
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ATTACHMENT F – FACT SHEET F-104
TMDL Constituent Waterbody Existing
Limitation New Limitation
Verdugo Wash 0.18 kg/day 0.39 kg/day
Rio Hondo Reach 1 0.01 kg/day 0.097 kg/day
Compton Creek 0.04 kg/day 0.13 kg/day
LAR Reach 4 26 μg/L 103 μg/L
LAR Reach 3 above
LAG WRP 23 μg/L 91 μg/L
Verdugo Wash 23 μg/L 50 μg/L
LAR Reach 3 below
LAG WRP 26 μg/L 103 μg/L
Burbank Western
Channel (above WRP) 26 μg/L 124 μg/L
Burbank Western
Channel (below WRP) 19 μg/L 90 μg/L
LAR Reach 2 22 μg/L 87 μg/L
Arroyo Seco 22 μg/L 29 μg/L
LAR Reach 1 23 μg/L 91 μg/L
Compton Creek 19 μg/L 64 μg/L
Rio Hondo Reach 1 13 μg/L 126 μg/L
Los Angeles River and
tributaries

1.5 x 10-8 x
daily storm
volume (L) –

9.5 g/day

6.0 x 10-8 x daily
storm volume (L) –

9.5 g/day
Lead
LAR Reach 6 0.33 kg/day 3.0 kg/day
LAR Reach 5 0.03 kg/day 0.31 kg/day
LAR Reach 4 0.12 kg/day 1.04 kg/day
LAR Reach 3 0.03 kg/day 1.18 kg/day
LAR Reach 2 0.07 kg/day 0.89 kg/day
LAR Reach 1 0.07 kg/day 0.64 kg/day
Bell Creek 0.04 kg/day 0.33 kg/day
Tujunga Wash 0.0002 kg/day 0.0053 kg/day
Burbank Western
Channel 0.07 kg/day 0.61 kg/day
Verdugo Wash 0.10 kg/day 0.82 kg/day
Arroyo Seco 0.01 kg/day 0.06 kg/day
Rio Hondo Reach 1 0.006 kg/day 0.045 kg/day
Compton Creek 0.02 kg/day 0.16 kg/day
LAR Reaches 5, 6 and
Bell Creek 19 μg/L 170 μg/L

EXHIBIT A
Tuesday, October 07, 2025 Reg CC MTG, Page *470
MS4 DISCHARGES WITHIN THE ORDER NO. R4-2021-0105
LOS ANGELES REGION NPDES NO. CAS004004
ATTACHMENT F – FACT SHEET F-105
TMDL Constituent Waterbody Existing
Limitation New Limitation
LAR Reach 4 10 μg/L 83 μg/L
LAR Reach 3 above
LAG WRP 12 μg/L 102 μg/L
Verdugo Wash 12 μg/L 102 μg/L
LAR Reach 3 below
LAG WRP 12 μg/L 100 μg/L
Burbank Western
Channel (above WRP) 14 μg/L 126 μg/L
Burbank Western
Channel (below WRP) 9.1 μg/L 751 μg/L
LAR Reach 2 11 μg/L 94 μg/L
Arroyo Seco 11 μg/L 94 μg/L
LAR Reach 1 12 μg/L 102 μg/L
Compton Creek 8.9 μg/L 73 μg/L
Rio Hondo Reach 1 5.0 μg/L 37 μg/L
Los Angeles River and
tributaries

5.6 x 10-8 x
daily storm
volume (L) –

3.85 g/day

8.5 x 10-8 x daily
storm volume (L) –
32 g/day
Los
Angeles
River
Nitrogen
Compounds
and Related
Effects
TMDL
Ammonia
30-day
Average
Los Angeles River
Reach 5 1.6 mg/L

2.1 mg/L

1.8 mg/L
LAR Reach 4 1.6 mg/L 2.1 mg/L
LAR Reach 3 above
LAG WRP 1.6 mg/L

4.1 mg/L

2.4 mg/L
LAR Reach 3 below
LAG WRP 2.4 mg/L 4.1 mg/L
Rio Hondo Reach 3
above Whittier Narrows
Dam

2.3 mg/L

4.3 mg/L

2.8 mg/L
Colorado
Lagoon OC
Pesticides,
PCBs,
Sediment
Toxicity,
PAHs and
Metals
TMDL
Lead
Termino Avenue Storm
Drain
1,134,867.12
mg/yr
None
Zinc 3,645,183.47
mg/yr
Total
Chlordane 12.15 mg/yr
Dieldrin 0.49 mg/yr
Total PAHs 97,739.52
mg/yr

EXHIBIT A
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MS4 DISCHARGES WITHIN THE ORDER NO. R4-2021-0105
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ATTACHMENT F – FACT SHEET F-106
TMDL Constituent Waterbody Existing
Limitation New Limitation
Total PCBs 551.64 mg/yr
Total DDTs 38.40 mg/yr
Colorado
Lagoon OC
Pesticides,
PCBs,
Sediment
Toxicity,
PAHs and
Metals
TMDL
Lead
Line M Storm Drain
68,116.09
mg/yr
None
Zinc 218,788.29
mg/yr
Total
Chlordane 0.73 mg/yr
Dieldrin 0.03 mg/yr
Total PAHs 5,866.44 mg/yr
Total PCBs 33.11 mg/yr
Total DDTs 2.30 mg/yr
Middle
Santa Ana
River
Watershed
Bacterial
Indicator
TMDLs
Fecal
Coliform
San Antonio Creek and
Chino Creek
30-Day
Geometric
Mean (GM)
less than
180/100 mL
None
Not more than
10% exceed
360/100 mL
during any 30-
day period
E. coli San Antonio Creek and
Chino Creek
30-Day GM
less than
113/100 mL
Not more than
10% exceed
212/100 mL
during any 30-
day period
Upper
Santa Clara
River
Chloride
TMDL
Chloride Reaches 4B and 5
(Ventura County only)
100 mg/L None
U.S. EPA
Established
- Santa
Clara River
Reach 3
Chloride Santa Clara River
Reach 3 80 mg/L 100 mg/L

EXHIBIT A
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ATTACHMENT F – FACT SHEET F-107
TMDL Constituent Waterbody Existing
Limitation New Limitation
Chloride
TMDL
Santa Clara
River
Estuary and
Reaches 3,
5, 6, & 7
Indicator
Bacteria
TMDL
E. coli Santa Clara River
Reaches 5, 6, and 7
0 allowable
exceedances
days at the
outfall
Exceedance days
now allowed at the
outfall and are the
same as the
allowable
exceedance days
for receiving water
What follows is a discussion of (1) the general law pertaining to anti-backsliding and (2) why the anti-backsliding provisions in the CWA and federal regulations do not bar the changes in the effluent limitations appearing in the Order.

1. General Principles of Law Governing Anti-Backsliding Analysis for Effluent Limitations Established Pursuant to TMDLs
As noted above, the CWA contains both statutory anti-backsliding provisions in section 402(o) and regulatory anti-backsliding provisions in 40 C.F.R. section 122.44(l). The CWA’s statutory prohibition against backsliding applies under a narrow set of criteria specified in section 402(o).72 Section 402(o)(1) prohibits relaxing technology based effluent limitations originally established based on best professional judgment, when there is a newly revised effluent limitation guideline.

This section is inapplicable here since none of the WQBELs in the Order are TBELs based on BPJ. Section 402(o)(1) also prohibits relaxing of WQBELs imposed pursuant to CWA sections 301(b)(1)(C) or 303(d) or (e). However, backsliding may be allowed for WQBELs such as the ones at issue here pursuant to one of six exceptions in CWA section 402(o)(2).
73 Two are relevant here:
72 See SWRCB Order WQ 2015-0075 at pp. 19-23; NPDES Permit Writers’ Handbook at §7.2.1.1 (U.S.

EPA 2010).
73 NPDES Permit Writers’ Manual, § 7.2.1.3 (U.S. EPA 2010); CWA section 402(o). Relaxation of limits based on state water quality standards may not be based on section 402(o)(B)(ii), which allows TBELs based on BPJ to be relaxed if technical mistakes or mistaken interpretations of the law were made in issuing the permit under CWA section 402(a)(1)(B).

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ATTACHMENT F – FACT SHEET F-108
▪ material and substantial alterations or additions to the permitted facility occurred after permit issuance which justify the application of a less stringent effluent limitation (CWA section 402(o)(A));
▪ information is available which was not available at the time of permit issuance (other than revised regulations, guidance, or test methods) and which would have justified the application of a less stringent effluent limitation at the time of permit issuance (the “New Information Exception”) (402(o)(2)(B)(i));
Relaxation of WQBELs may also be allowed if such backsliding is consistent with the provisions in CWA section 303(d)(4). CWA section 303(d)(4) allows backsliding in the following circumstances. First, “CWA section 303(d)(4)(A) allows the establishment of a less stringent effluent limitation when the receiving water has been identified as not meeting applicable water quality standards (i.e., a nonattainment water)” if two conditions are met: (a), “the existing effluent limitation must have been based on a …TMDL or other …WLA established under CWA section 303;” and (b) “relaxation of the effluent limitation is only allowed if attainment of water quality standards will be ensured or the designated use not being attained is removed in accordance with the water quality standards regulations.”74
Second, section 303(d)(4)(B), applies to “waters where the water quality equals or exceeds levels necessary to protect the designated use, or to otherwise meet applicable water quality standards (i.e., an attainment water). Under CWA section 303(d)(4)(B), a limitation based on a TMDL, WLA, other water quality standard, or any other permitting standard may only be relaxed where the action is consistent with state’s antidegradation policy.”75
Here, the WQBELs are imposed pursuant to section 303(d). For purposes of the following analysis, both sections 303(d)(4) and the exceptions in section 402(o)(2) are relevant because “U.S. EPA has consistently interpreted CWA section 402(o)(1) to allow relaxation of WQBELs and effluent limitations based on state standards if the relaxation is consistent with the provisions of CWA section 303(d)(4) or if … [certain] of the exceptions in CWA section 402(o)(2)… [apply].

The two provisions [303(d)(4) and 402(o)(2)] constitute independent exceptions to the prohibition against relaxation of effluent limitations. If either is met, relaxation is permissible.”76 As set forth below, the changes to numeric WQBELs in the Order either do not constitute backsliding or satisfy one or more of the foregoing exceptions to anti-backsliding as described below.

2. WQBEL Revisions That Do Not Constitute Backsliding
a. Marina del Rey Harbor Toxic Pollutants TMDL
The 2012 Permit for the County of Los Angeles incorporated the Marina del Rey Harbor Toxic Pollutants TMDL and included numeric WQBELs consistent with the assumptions and requirements of the WLAs in the TMDL as adopted in 2005. (Resolution No. 2005-012. (2005 TMDL.)). The TMDL was reconsidered in 2014 (Resolution R14-004 (2014 TMDL)). The Order updates the WQBELs for copper, lead, zinc, total chlordane, and total PCBs in Marina 74 NPDES Permit Writers’ Manual, § 7.2.1.3 (U.S. EPA 2010); CWA section 303(d)(4)(A). 75 NPDES Permit Writers’ Manual, § 7.2.1.3 (U.S. EPA 2010); CWA section 303(d)(4)(B). 76 NPDES Permit Writers’ Manual, § 7.2.1.3 (U.S. EPA 2010); CWA sections 303(d)(4) and 402(o)(2).

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ATTACHMENT F – FACT SHEET F-109
del Ray Harbor consistent with the assumptions and requirements in the 2014 TMDL.

In the 2005 TMDL, the geographical area in which the toxic impairments were found were confined to the back basins of the Marina del Rey Harbor. During the 2014 reconsideration, the Los Angeles Water Board evaluated data collected since adoption of the TMDL and found that the toxic impairments were also present in several of the front basins.77 Therefore, the 2014 TMDL revised the geographic area addressed by the TMDL to include the whole harbor and updated the percentage of land area covered by the MS4 permittees to account for areas draining into the front basins.78 The 2014 TMDL adjusted the loading capacity and waste load allocations based on the revised geographic area.

The WQBELs in the Order are equal to the adjusted waste load allocations for copper, lead, zinc, total chlordane, and total PCBs in the 2014 TMDL. Because the increased geographic area resulted in an increased loading capacity of sediment bound pollutants discharged to Marina del Rey Harbor through stormwater, the WQBELs assigned to responsible MS4 permittees in the Order allow increased loadings of these constituents.

However, even though increased loadings are allowed, the WQBELs are not less stringent than before. In the 2014 TMDL analysis, the Los Angeles Water Board relied on the same the linkage analysis as the 2005 TMDL.79 Similarly, the numeric sediment targets used to calculate the loading capacity and waste load allocations remained the same as the 2005 TMDL. The increased allowable loading is a result of adding the expanded geographic area to the analysis and its associated TSS loading. The increased allowable loading is spread out over the expanded geographic area. Therefore, while the WQBELs for copper, lead, zinc, total chlordane and total PCBs have increased, they are still as protective as the WQBELs in the 2012 Los Angeles County Permit.

Even if anti-backsliding applies, the imposition of new WQBELs for copper, lead, zinc, total chlordane and total PCBs satisfies the anti-backsliding exception in CWA section 303(d)(4)(A) because the revisions in the 2014 TMDL will assure attainment of water quality standards. Indeed, TMDLs are developed for the purpose of specifying requirements for the achievement of water quality standards in impaired water bodies.80 The additional loading of sediment-bound pollutants was solely to account for the expanded scope of the TMDL and no changes were made to the implementation schedule for the back basins.
b. Ballona Creek Metals TMDL
The 2012 Los Angeles County Permit incorporated numeric WQBELs consistent with the assumptions and requirements of the Ballona Creek Metals TMDL (Resolution No. R07-015), which became effective in 2008. In 2013, the Los Angeles Water Board reconsidered and revised this TMDL (Resolution No. R13-010). The revised TMDL became effective in 2015. The 77 (Staff Report p. 6).
78 (Staff Report p. 6 and 24)
79 (Staff Report p. 8).
80 (33 U.S.C. 1313(d); 40 C.F.R. §130.7.)

EXHIBIT A
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ATTACHMENT F – FACT SHEET F-110
Order updates the WQBELs consistent with the assumptions and requirements of the revised Ballona Creek TMDL. Specifically:
▪ the final mass-based and concentration-based WQBELs for copper, lead and zinc allow increased loadings during dry weather; and ▪ the final mass-based WQBEL for lead allows increased loading during wet weather.

Although these revisions to the WQBELs allow increased loadings of copper, lead, and zinc, these changes do not constitute backsliding because the revised TMDL on which they are based used site-specific information to recalculate the WLAs, which did not change the intended level of protection.

During the 2013 reconsideration, the Los Angeles Water Board evaluated additional, more recent flow data, hardness data, and dissolved to total metals ratios. These robust data sets resulted in adjustments to flow rates, hardness and conversion factors that compelled revisions to the dry- and wet-weather numeric targets. The dry-weather numeric targets for copper, lead and zinc increased, which in turn increased the dry-weather WLAs for copper, lead and zinc. Likewise, the wet-weather numeric target for lead increased, which increased the wet-weather WLA for lead.81 The WQBELs in the Order are equal to the revised WLAs.

Even if anti-backsliding applies, each of these changes meets the antibacksliding exception set forth in CWA section 303(d)(4)(A). Section 303(d)(4)(A) of the CWA allows relaxation of effluent limits in non-attainment waters if “the cumulative effect of all such revised effluent limitations based on such total maximum daily load or waste load allocation will assure the attainment of such water quality standard, or (ii) the designated use which is not being attained is removed in accordance with regulations” established under the CWA. These revisions were made in accordance with the revised WLAs in the revised TMDL, which will assure the attainment of water quality standards for copper, lead and zinc in dry weather, and for lead in wet weather. Attainment of these water quality standards will occur within a reasonable time frame, set forth in the implementation schedule. c. Los Angeles River Nitrogen Compounds and Related Effects TMDL The 2012 Permit for the County of Los Angeles incorporated WQBELs consistent with the assumptions and requirements of the Los Angeles River (LAR) Nitrogen Compounds and Related Effects TMDL (LAR Nitrogen TMDL) (Resolution NO. R03-009).82 In 2012, the Los Angeles Water Board reconsidered and revised the LAR Nitrogen TMDL to incorporate site-specific, seasonal objectives for ammonia, expressed as temperature- and pHdependent equations for Reaches 3-5 of the river and Rio Hondo Reach 3. (Resolution No. 12-010). These revisions became effective on August 7, 2014.

The Order therefore updates the numeric WQBELs consistent with the assumption and requirements of the 2012 revisions of the LAR Nitrogen 81 The wet-weather numeric targets for copper and zinc decreased which resulted in a decrease of the wetweather WLAs for copper and zinc. (Section 3.1.5.1, pp. 15-16 of the Staff Report.) 82 The implementation plan for LAR Nitrogen TMDL was amended by Resolution No. 03-016 to align certain interim ammonia WLAs with planned construction projects. The TMDL remained unchanged in all other respects.

EXHIBIT A
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TMDL. The updated WQBELs were calculated using three years of sitespecific temperature and pH data (1/1/2018 - 12/31/2020) consistent with the WLA equations and implementation provisions in the 2012 revised TMDL.

The original LAR Nitrogen TMDL included numeric targets and WLAs for ammonia based on U.S. EPA’s “1999 Update of Ambient Water Quality Criteria” for Ammonia. EPA’s updated ammonia criteria included thirty-day average water quality objectives that are a function of temperature and pH, which can affect ammonia toxicity to fish. The objectives are thus expressed as equations. There are separate equations for waterbodies with and without early life stages of fish, which are more sensitive to ammonia. The more stringent equation applies to waterbodies with early life stages of fish. The 1999 Update also allows for the development of a water effects ratio (WER) to adjust the equation. WERs account for site-specific conditions that also affect ammonia toxicity. In the absence of site-specific information, a default WER of 1.0 is used. At the time of the LAR Nitrogen TMDL adoption in 2003, the Basin Plan did not specifically identify, which reaches in the Los Angeles Region, where early life stages of fish were present or absent. As such, the numeric targets and WLAs for ammonia in the original LAR Nitrogen TMDL assumed that early life stages of fish were absent in the Los Angeles River watershed.83 Additionally, the numeric targets and WLAs for ammonia in the TMDL were calculated using the default WER value of “1” because a WER study was still under development.

In 2005 and 2007, the Los Angeles Water Board adopted seasonal, sitespecific ammonia objectives for the San Gabriel, Los Angeles, and Santa Clara River Watersheds.84 These objectives became effective on April 5, 2007 and April 23, 2009, respectively, changing the previous 30-day average ammonia objective in Chapter 3 of the Basin Plan for a subset of inland surface waters, including Reaches 3-5 of the LAR and Reach 3 of the Rio Hondo, upstream of Whittier Narrows Dam. The new site-specific objectives incorporated WERs for these reaches and defined seasonal periods of early life stages of fish presence and absence in these reaches.85 In 2012, the LAR Nitrogen TMDL was revised to conform the numeric targets and WLAs with the updated seasonal, site-specific objectives for Los Angeles River Reaches 3-5, and Rio Hondo Reach 3, upstream of Whittier Narrows Dam. Specifically, the TMDL’s thirty-day average numeric targets and associated WLAs for Los Angeles River Reaches 3-5, and Rio Hondo Reach 3 were changed to the site-specific equations for “early life stages (of fish) present” and “early life stages (of fish) absent” periods. These equations incorporate a site-specific WER value and are temperature and pH dependent. The TMDL notes that it would be consistent with the assumptions 83 TMDL for Nitrogen Compounds and Related Effects, Los Angeles River and Tributaries, Staff report (May 2, 2003; Revised July 10 2003) p. 37.
84 Resolution R07-005
85 “The SSOs are based on the results of a WER study completed by the City of Los Angeles, County Sanitation Districts of Los Angeles County, and the City of Burbank. These SSOs, in addition to ammonia SSOs for the San Gabriel and Santa Clara River watersheds, were previously incorporated into the Basin Plan by resolution 2007-005, adopted by the Regional Board on June 7, 2007. By adopting the SSOs into the Basin Plan, they are now the applicable ammonia water quality objectives for the rivers and reaches to which they apply.” (December 6, 2012, Final Staff Report p. 3.) See also Basin Plan page 3-14 and 3-15.

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and requirements of the TMDL to translate the WLA into effluent limitations by using the past three years of temperature and pH data.86 The Order calculates the 30-day average ammonia WQBELs in the LAR watershed using the site-specific, seasonal objectives for Los Angeles River Reaches 3-5, and Rio Hondo Reach 3, upstream of Whittier Narrows Dam.

Three years of temperature and pH data was obtained from receiving water monitoring from the Donald C. Tillman Water Reclamation Plant (WRP), the Los Angeles-Glendale WRP, and the Whittier Narrows WRP. Based on these calculations the 30-day effluent limitations for total ammonia when “early life stages present” and when “early life stages absent” increased in the Los Angeles River Reaches 3-5 and Rio Hondo Reach 3. Although the revisions to the ammonia WQBELs in the Order allow increased loadings of ammonia, these changes do not constitute backsliding because the updated WQBELs are based on site-specific information that achieve the same intended level of protection. The revised WLAs are still based on the same ammonia criteria equations. The WER term in the equations has merely been updated to reflect site-specific conditions and recent data have been inserted into the equations to calculate the WQBELs.

But even if the changes described above were subject to CWA section 402(o)’s anti-backsliding provisions, the revisions to these WQBELs comply with CWA section 304(d)(4)(A). Section 303(d)(4)(A) of the CWA allows relaxation of effluent limits in non-attainment waters if “the cumulative effect of all such revised effluent limitations based on such total maximum daily load or waste load allocation will assure the attainment of such water quality standard, or (ii) the designated use which is not being attained is removed in accordance with regulations” established under the CWA. Here, the water quality objective itself was adjusted, and the revised TMDL reflects this. Any changes to WQBELs are recalculated as directed in the TMDL. Compliance with the WQBELs will therefore ensure the attainment of the site-specific objectives for ammonia in these four reaches of surface waters, within a reasonable time frame set forth in the implementation schedule. d. Los Angeles River and Tributaries Metals TMDL
The 2012 Permit for the County of Los Angeles incorporated WQBELs consistent with the assumptions and requirements of the Los Angeles River and Tributaries Metals (LAR Metals TMDL).87 In 2015, the Los Angeles Water Board reconsidered and revised the LAR Metals TMDL to incorporate sitespecific water-effect ratios for calculating the copper water quality objectives and site-specific water quality objectives for lead for a number of reaches in the Los Angeles River watershed. (Resolution No. 15-004). The site-specific copper WERs and lead water quality objectives and revisions to the TMDL became effective on December 12, 2016. U.S. EPA withdrew the previously effective water quality criteria for lead from the California Toxics Rule (CTR) for the portions of the Los Angeles River watershed subject to the TMDL, effective November 15, 2018. The Order updates the WQBELs for copper and 86 Basin Plan p. 7-91.
87 The Los Angeles Water Board approved the LAR Metals TMDL in 2007 (Resolution No. R2007-0014). A TMDL revision applicable to POTWs was adopted in 2010 (R10-003). The revised TMDL became effective on November 3, 2011.

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lead in the reaches identified in Table F-21 consistent with the assumptions and requirements of the revised LAR Metals TMDL. Although the revisions to these WQBELs allow increased loadings of copper and lead, the increased loadings do not constitute backsliding because the WQBELs provide the same level of intended protection and are no less stringent as described below. i. Copper
The numeric targets and WLAs for the LAR Metals TMDL are based on the water quality objectives for copper in the CTR. The CTR water quality objectives for copper are expressed as equations, which include a term called a water effect ratio or WER. The WER reflects the effect that local site water constituents have on the toxicity of copper. The CTR equation includes a default WER of 1.0, which assumes that metals are equally toxic in local site water as they are in lab water. The WER may be adjusted using a properly conducted WER study. A WER greater than

1.0 means the local site water reduces the toxicity of copper and a WER less than 1.0 means that local site water increases the toxicity of copper.

The numeric targets and WLAs for copper in the LAR Metals TMDL were based on a default WER value of 1.0.

The LAR Metals TMDL was revised in 2015 based on the results of a properly conducted WER study for Reaches 1, 2, 3, and 4 of the Los Angeles River, Compton Creek, Rio Hondo, Arroyo Seco, Verdugo Wash, Burbank Western Channel and Tujunga Wash.
88 The TMDL
recalculated the numeric targets and WLAs for copper to reflect sitespecific WERs for copper, as determined by the study.

The WQBELs in the Order are equal to the WLAs for copper in the revised LAR Metals TMDL. Incorporating WQBELs equal to the revised WLAs does not change the intended level of protection because the revised WLAs are still based on the same CTR equation for copper -- only the WER term in the equation has been updated to reflect site-specific conditions. The updated WQBELs merely reflect the fact copper is less toxic to aquatic life in the Los Angeles River receiving waters than it is in lab water.
ii. Lead
The numeric targets and WLAs for lead in the LAR Metals TMDL are based on the water quality objectives for lead in the CTR, which are based on a national toxicity dataset. U.S. EPA allows for the derivation of site-specific objectives using the Recalculation Procedure. 89 The
Recalculation Procedure provides a method for adjusting the national dataset based on more recent toxicity studies.

The LAR Metals TMDL was revised in 2015 to incorporate recalculated lead water quality objectives based on the results of a special study that followed the Recalculation Procedure.
90 The study recalculated the acute
88 Final Report: Copper Water-Effect Ratio Study to Support Implementation of the Los Angeles River and Tributaries Metals TMDL (2014)
89 USEPA Water Quality Standards Handbook: Second Edition (1994) 90 Final Lead Recalculation Report to Support Implementation of the Los Angeles River and Tributaries Metals TMDL (2014)

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and chronic lead objectives for portions of the Los Angeles River using an expanded nation-wide dataset provided by U.S. EPA. The recalculated objectives were compared to toxicity data for species of interest in the Los Angeles River Watershed to ensure the objectives were protective of local species. The TMDL updated the numeric targets and WLAs based on the recalculated lead objectives.91 The resulting numeric targets and WLAs for lead were greater than the numeric targets and WLAs in the original LAR Metals TMDL. The WQBELs in the Order are based on the updated WLAs. Although the WQBELs for lead increased from the 2012 Los Angeles MS4 Permit, these effluent limitations are not less stringent. These effluent limitations are based on site-specific numeric targets and WLAs, which were based on an updated toxicity dataset and the recalculation of the water quality objectives following U.S. EPA guidelines. The study showed that the recalculated objectives for lead are protective of aquatic life, and the U.S. Fish and Wildlife Service agreed that the objectives would not likely adversely affect any listed threatened or endangered species or their critical habitat.92
Conclusion. Even if anti-backsliding applies to the revised copper and lead WQBELs discussed above, each of these changes meets the anti-backsliding exception set forth in CWA section 303(d)(4)(A). Section 303(d)(4)(A) of the CWA allows relaxation of effluent limits in non-attainment waters if “the cumulative effect of all such revised effluent limitations based on such total maximum daily load or waste load allocation will assure the attainment of such water quality standard, or (ii) the designated use which is not being attained is removed in accordance with regulations” established under the CWA.

These revisions were made in accordance with the revised WLAs in the revised TMDL, which will ensure the attainment of water quality standards for copper and lead. Attainment of these water quality standards will occur within a reasonable time frame set forth in the implementation schedule. e. Middle Santa Ana River Watershed Bacterial Indicator TMDL The Order removes the Middle Santa Ana River Watershed Bacterial Indicator TMDL (MSAR Bacteria TMDL) WQBELs applicable to the cities of Claremont’s and Pomona’s MS4. Claremont and Pomona are subject to regulations by the Los Angeles Water Board and Santa Ana Water Board. To streamline regulatory requirements, Water Code section 13228 authorizes persons regulated by more than one regional water board to request designation of a single regulator. In 2013, the Los Angeles Water Board and the Santa Ana Water Board agreed to designate the Santa Ana Water Board as the single regulator of discharges of bacteria by Claremont and Pomona through their MS4s to the receiving waters within the Middle Santa Ana River Watershed.93 On September 13, 2013, the Santa Ana Water Board adopted Order No. R8-2013-0043 (NPDES No. CA8000410) to implement the MSAR Bacteria TMDL. Accordingly, the WQBELs implementing the MSAR Bacteria 91 Section 4.2, pp. 8-9 of the Staff Report.
92 83 Fed. Reg. 52166-52168 (Oct. 16, 2018).
93 May 31, 2013 letter and memorandum of understanding by and between Los Angeles Water Board and Santa Ana Water Board (signed by Samuel Unger, Executive Officer, Los Angeles Water Board, and Kurt Berchtold, Executive Officer, Santa Ana Water Board).

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TMDL are removed from the Order. Because the cities of Pomona and Claremont are still subject to these WQBELs through another permit, no backsliding has occurred.

3. WQBEL Revisions that Fall Within an Exception to Backsliding a. Ballona Creek Metals TMDL
As previously discussed, the Ballona Creek Metals TMDL was reconsidered and revised in 2013. In addition to the changes to copper, lead and zinc set forth above, the revised 2013 Ballona Creek Metals TMDL removed WLAs for selenium because the receiving water is no longer considered impaired for selenium. In making this determination, the Los Angeles Water Board considered recent selenium data as well the data considered during the adoption of the Ballona Creek Metals TMDL in 2008. These data were evaluated pursuant to the State Water Board’s Water Control Policy for Developing California’s Clean Water Act Section 303(d) List (Listing Policy), which uses a weight of the evidence approach to evaluate whether to place waters on, or remove waters from, the 303(d) List. The reexamined data satisfied the delisting requirements in Table 4.1 of the Listing Policy and the Los Angeles Water Board approved removing selenium from the Ballona Creek Metals TMDL.

The Order therefore removes the selenium WQBELs for Ballona Creek Reach

2. Removal of the selenium WQBELs for Ballona Creek Reach 2 in the Order satisfies the anti-backsliding exception set forth in CWA section 303(d)(4)(B) because this reach is no longer impaired for selenium and MS4 discharges will not result in degradation. With the reconsideration of the TMDL, the Los Angeles Water Board determined that existing in stream beneficial uses and the level of water quality necessary to protect the beneficial uses would be maintained if selenium WLAs, and associated WQBELs, were removed. Even though there might be some discharges of selenium to Ballona Creek, any such discharges will be limited or minor with respect to the assimilative capacity of Ballona Creek and will not result in any long-term deleterious effects on water quality as shown in the water quality data assessment for the TMDL revision. (See, also, discussion in Fact Sheet, Part III.H, supra.) Furthermore, MS4 dischargers are still required to comply with receiving water limitations in Part V of the Order and are required to monitor for selenium in the Order. Continued monitoring for selenium ensures that any adverse changes in water quality with respect to selenium will be caught and corrected. b. Ballona Creek Estuary Toxics TMDL
The 2012 Los Angeles County Permit incorporated numeric WQBELs consistent with the assumptions and requirements of the Ballona Creek Toxics TMDL (Resolution No. R05-008). In 2013, the Los Angeles Water Board reconsidered and revised this TMDL (Resolution No. R13-010). The revised TMDL became effective in 2015. The Order updates the numeric WQBELs consistent with the assumptions and requirements of the revised Ballona Creek Toxics TMDL. Specifically:
▪ the WQBELs for sediment for Chlordane and total DDTs were increased and
▪ the WQBELs for total PAHs were removed.

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The rationale for these revisions is as follows:
i. Chlordane and DDTs
The numeric targets and WLAs for metals and organic pollutants in the Ballona Creek Estuary Toxics TMDL were originally based on National Oceanic and Atmospheric Administration’s (NOAA) sediment quality guidelines. In 2009, the State Water Board adopted its Water Quality Control Plan for Enclosed Bays & Estuaries – Part 1 Sediment Quality (Sediment Quality Plan). The Sediment Quality Plan includes (1) a narrative sediment objective to protect benthic communities, and (2) a narrative sediment objective to protect human health. The Sediment Quality Plan established a methodology based on integrating multiple lines of evidence (MLOE) to determine whether the narrative sediment objective for benthic communities is achieved. This assessment is sometimes called a “direct effects” assessment for the direct effect of contaminants on benthic organisms and does not include an assessment of the “indirect effects” of contaminants transferring up the food chain to fish, which can impact human health.94 The Sediment Quality Plan directed the State and Regional Water Boards to implement the narrative sediment objective to protect human health on a case-by-case basis, based upon a human health risk assessment.95
During the reconsideration, the Los Angeles Water Board evaluated Ballona Creek Estuary using the MLOE approach in the Sediment Quality Plan. This evaluation indicated that at least one station in the Ballona Creek Estuary exceeded the sediment objectives for benthic communities.96 The Los Angeles Water Board also considered the results of a Toxicity Identification Evaluation study conducted in 2010 (2010 TIE).

This study found that the principal source of sediment toxicity in the Ballona Creek Estuary was pyrethroids. Based on these studies, the Los Angeles Water Board determined that total DDTs and chlordane were not causing “direct effect” impairments to the benthic community.97 Nonetheless, monitoring data collected as part of the TMDL coordinated monitoring plan indicated that exceedances of total DDTs and chlordane targets in sediment were ongoing.
98 Total DDTs were present in limited
fish sampling.99 And in 2009, Ballona Creek was identified a fish consumption “red zone,” with 5 fish listed as “do not eat” and 14 fish with recommended consumption limitations.100 The Los Angeles Water Board therefore conducted a human health risk assessment consistent with the Sediment Quality Plan to implement the narrative sediment objective to protect human health.101
94 Staff report 19-20.
95 https://www.waterboards.ca.gov/water_issues/programs/bptcp/docs/sediment/sed_qlty_part1.pdf at p.

13. 96 Staff report p. 22.
97 See staff report p. 23.
98 Staff report pp. 3 and 23.
99 Ibid.
100 Staff report pp. 24-25
101 https://www.waterboards.ca.gov/water_issues/programs/bptcp/docs/sediment/sed_qlty_part1.pdf at p.

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The Sediment Quality Plan directed regional water boards to consider any applicable and relevant information, including but not limited to the California Environmental Protection Agency’s Office of Environmental Health Hazard Assessment (OEHHA) policies for fish consumption and risk assessment. In 2008, OEHHA developed Fish Contaminant Goals for Chlordane and total DDTs.102 During the reconsideration of the Ballona Creek Toxics TMDL, the Los Angeles Water Board replaced the direct effects numeric targets for chlordane and total DDTs in sediment with indirect effects numeric targets for chlordane and total DDTs in sediment using OEHHA’s Fish Contaminant Goals. The new numeric targets and resulting WLAs for chlordane and total DDTs increased.103 The WQBELs for chlordane and DDTs in the Order have been adjusted accordingly.

The changes described above meet the anti-backsliding exception set forth in CWA section 303(d)(4)(A) because any relaxation of the WQBELs for chlordane and total DDTs in the Order was made as a result of the reconsidered TMDL. Although the waters remain impaired, the changes to the WQBELs are consistent with the assumptions and requirements of the WLAs in the revised TMDL. The revised TMDL’s limits are designed to attain water quality standards, and the WQBELs ensure this will happen within a reasonable time frame.
ii. Total PAHs
In addition to the foregoing, the numeric targets and WLAs for total PAHs were removed from the Ballona Creek Estuary Toxics TMDL in the 2013 reconsideration. Removal was based on application of criteria in the Listing Policy to sediment samples collected since the adoption of the TMDL in 2005. The reexamined data satisfied the delisting requirements in Table 4.1 of the Listing Policy and the Los Angeles Water Board approved removing total PAHs from the Ballona Creek Toxics TMDL.

Removal of total PAHs from the Order satisfies the exception to antibacksliding in CWA section 303(d)(4)(B). The waters here are no longer impaired for total PAHs, and MS4 discharges will not result in degradation. With the reconsideration of the TMDL, the Los Angeles Water Board determined that existing in stream beneficial uses and the level of water quality necessary to protect the beneficial uses would be maintained if total PAH WLAs, and associated WQBELs, were removed.

There have been no exceedances in any of the samples collected and analyzed, but even if there might be some discharges, any such discharges will be limited or minor with respect to the assimilative capacity of Ballona Creek. (See, also, discussion in Fact Sheet, Part III.H, supra.) Furthermore, MS4 dischargers are still required to comply with receiving water limitations in Part V of the Order and are required to monitor for total PAHs in the Order. Continued monitoring for total PAHs 102 Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish:

Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene” (FCGs), at https://oehha.ca.gov/fish/report/fish-contaminant-goals-and-advisory-tissue-levels-evaluatingmethylmercury-chlordane. 103 The numeric targets, WLA, and LAs for total PCBs are more stringent after the revision to the TMDL.

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in sediment will ensure that any adverse changes in water quality with respect to total PAHs in sediment will be caught and corrected. c. Colorado Lagoon TMDL
The 2012 Los Angeles County Permit incorporated WQBELs for lead, zinc, total chlordane, dieldrin, total PAHs, total PCBs, and Total DDTs consistent with the assumptions and requirements of the Colorado Lagoon TMDL. The Order removes these WQBELs for two discharge points: Termino Avenue and Line M because these two storm drains were physically rerouted such that they no longer discharge into the Colorado Lagoon. These alterations, which were structural changes to the MS4 itself, are “material and substantial alterations or additions to the permitted facility” and justify the application of a less stringent effluent limitation under CWA section 402(o)(2)(A). d. Revolon Slough and Beardsley Wash Trash TMDL
The 2010 Ventura County Permit incorporated WQBELs of zero trash consistent with the assumptions and requirements of the Revolon Slough and Beardsley Wash Trash TMDL (Resolution No. 2007-007; Revolon/Beardsley Trash TMDL). The Revolon/Beardsley Trash TMDL required MS4 responsible entities to address discharges of trash from all land uses with full capture systems, or other lawful manner.104 The Order revises the WQBELs to apply to discharges from priority land uses only. The rationale for this revision is as follows.

In 2015, the State Water Board adopted the Trash Amendments. As discussed in Part IV.B of this Fact Sheet, the Trash Amendments established a prohibition on the discharge of trash in all Waters of the State. Implementation of this discharge prohibition focuses MS4 compliance efforts on high trash generation areas or “priority land uses.” The Trash Amendments do not apply to waterbodies with a TMDL in effect prior to the effective date of the Trash Amendments (December 2, 2015). However, the State Water Board directed the Los Angeles Water Board to reconsider whether its existing trash TMDLs could be aligned with the Trash Amendments to focus on priority land use areas only.

In 2018, the Los Angeles Water Board reconsidered the Revolon/Beardsley Trash TMDL in light of the statewide Trash Amendments. The revised TMDL became effective on May 6, 2020. The Los Angeles Water Board concluded that a focus on priority land use areas would attain the numeric target of zero trash in the Revolon Slough/Beardsley subwatershed as long as nonpoint source responsible entities implemented Minimum Frequency of Assessment and Collection Program (MFAC) programs in the impaired waters downstream to address any potential trash discharged from nonpriority land uses. The TMDL revised the implementation provisions for the WLAs to require full capture systems for storm drains that capture runoff from priority land uses.

This amounts to a reduction in the amount of full capture systems installed in the subwatershed. The Order incorporates WQBELs consistent with the revised implementation provisions for the TMDL.
104 See page 3 of Attachment A to Resolution No. 2007-007 (Revolon Slough and Beardsley Wash Trash TMDL).

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The changes described above meet the anti-backsliding exception set forth in CWA section 303(d)(4)(A) because any relaxation of the WQBELs in the Order for trash are a result of the reconsidered TMDL. Although the waters remain impaired, the revised TMDL determined that implementation of full capture systems to address priority land uses only will attain the numeric target of zero trash for Revolon Slough and Beardsley Slough provided that nonpoint source responsible entities implement MFAC programs in the impaired waters downstream.105 Changes to the WQBELs consistent with the assumptions and requirements of the revised TMDL will ensure attainment of the water quality standard and is therefore permissible consistent CWA section 303(d)(4)(a). e. Malibu Creek Watershed Trash TMDL
The 2012 Los Angeles County Permit incorporated WQBELs of zero trash consistent with the assumptions and requirements of the Malibu Creek Watershed Trash TMDL (Resolution No. 2008-007; Malibu Trash TMDL). The Malibu Trash TMDL required MS4 responsible entities to address discharges of trash from all land uses with full capture systems, or other lawful manner.106 The Order revises the WQBELs to apply to discharges from priority land uses only. The rationale for this revision is as follows.

The Malibu Trash TMDL was revised at the same time and in the same manner as the Revolon Slough/Beardsley Wash TMDL discussed above (Resolution No. R4-2018-006). The revised TMDL became effective on May 6, 2020. Similar to the Revolon Slough/Beardsley Wash TMDL, the Los Angeles Water Board concluded it was appropriate to align the Malibu Trash TMDL with the Statewide Trash Amendments because installation of full capture devices in the priority land use areas would attain the numeric target of zero trash in the Malibu Creek watershed as long as nonpoint source responsible entities implement MFAC programs are in place in the impaired waters downstream to address any potential trash discharged from nonpriority land uses.107 The WQBELs of zero trash in the Order are limited to discharges from “priority land use areas” to Malibu Creek, Malibu Lagoon, Malibou Lake, Medea Creek (Reach 1 and Reach 2), Lindero Creek (Reach 1 and Reach 2), Lake Lindero, and Las Virgenes Creek of the Malibu Creek Watershed, instead of the whole Malibu Creek Watershed.

The changes described above meet the anti-backsliding exception set forth in CWA section 303(d)(4)(A) because any relaxation of the WQBELs in the Order for trash are a result of the reconsidered TMDL. Although the waters remain impaired, the revised TMDL determined that implementation full capture systems to address priority land uses only will attain the numeric target of zero trash for Malibu Creek Watershed provided that nonpoint source responsible entities implement MFAC programs in the impaired waters downstream.108 Changes to the WQBELs consistent with the assumptions and requirements of the revised TMDL will ensure attainment of the water quality standard and is therefore permissible consistent CWA section 303(d)(4)(a). 105 Page 23 of the Staff Report.
106 See page 3 of Attachment A to Resolution No. 2007-007 (Revolon Slough and Beardsley Wash Trash TMDL).
107 Page 44 of the Staff Report.
108 Page 44 of the Staff Report.

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f. Upper Santa Clara River Chloride TMDL
The Order relieves Ventura County Permittees from compliance with the chloride limits in the Upper Santa Clara River Chloride TMDL for Reaches 4B and 5 of the Santa Clara River, because the MS4s are not discharging into those Reaches. Removal is consistent with both CWA section 303(d)(4)(A)(i) and section 402(o)(B)(i).

The TMDL for Chloride in the Upper Santa Clara River was originally adopted in 2003 and went into effect in 2005. It was revised in 2008 and 2014, and the revisions went into effect in 2009 and 2015, respectively.

In drafting the Order, the Los Angeles Water Board examined the evidence and found that Ventura County Permittees have no MS4s that discharge into the chloride impaired reaches of the Upper Santa Clara River. Reach 5 falls partially within Ventura County, but Ventura County Permittees do not have any MS4 discharges to the portion of Reach 5 that falls within Ventura County.
109 Therefore, the Order assigns chloride WQBELs for discharges to Reach 5 exclusively to Los Angeles County Permittees draining to Reach 5.

For Reach 4B, although it is completely within Ventura County110, there are no MS4 discharges from Ventura County Permittees to Santa Clara River Reach 4B. Removal of the limits for Ventura County MS4 Facilities in the Order is therefore consistent with CWA section 303(d)(4) because removal will have no impact on the cumulative impact or effect of chloride loading in the Upper Santa Clara River. Put differently, the “cumulative effect” of this revised WLA for Ventura County Permittees will assure attainment of the water quality objectives, since they are not discharging through their MS4s to the Upper Santa Clara River.
g. U.S. EPA Established - Santa Clara River Reach 3 Chloride TMDL The 2010 Ventura County MS4 Permit has a WQBEL of 80 mg/L for discharges of chloride to Santa Clara River Reach 3. The Order revises the WQBEL from 80 mg/L to 100 mg/L. Revisions to WQBELs in attainment waters are permitted provided the change is consistent with the antidegradation policy pursuant to CWA section 303(d)(4)(B). The revision of the chloride WQBEL is consistent with the antidegradation policies for the following reasons:

The Santa Clara River Reach 3 Chloride TMDL intended to assign a WLA for chloride equal to the applicable water quality objective in the Basin Plan. At the time this TMDL was established on June 18, 2003, the Basin Plan Objective for Santa Clara River Reach 3 was 80 mg/L for chloride. In 2004, the Los Angeles Water Board changed the water quality objective for Santa Clara River Reach 3 from 80 mg/L to 100 mg/L (Resolution R03-015, effective on 8/4/2004). The TMDL on page 20, Section 10: Implementation Recommendations, states the following: “EPA understands that the State is in the process of reviewing and revising upward the numeric water quality objective for chloride in Santa Clara River Reach 3. Based on our review of the data used to support the State’s listing of Reach 3 for chlorides on the 2002 California Section 303(d) list, it appears possible that this Reach would 109 Ventura County GIS data and MS4 drainage area maps (July 15, 2016) 110 Ventura County GIS data and MS4 drainage area maps (July 15, 2016)

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not exceed water quality standards if the objective is raised to 100 mg/L as proposed by the State. EPA believes it would be reasonable for the State to defer full implementation of the TMDL for Reach 3 until this objective change is completed. If the State does not complete its proposed action to raise the chloride objective for Reach 3, the State should determine the appropriate means of implementing the TMDL through its NPDES permitting decisions and other programs to address nonpoint sources for which allocations are included in this TMDL”. The change to the Water Quality Objective was inadvertently not considered during the issuance of the 2010 Ventura County MS4 Permit. The Santa Clara River Reach 3 WQBEL of 80 mg/L in the 2010 Ventura County MS4 Permit has been revised to 100 mg/L in the Order to align it with the water quality objective in the Basin Plan. This is consistent with the assumptions and requirements of the TMDL to implement the applicable water quality objective, which is currently being met (see Part VI.F.2.b of this Fact Sheet). Additionally, because compliance with the revised WQBEL still requires compliance with the applicable water quality objective for this reach it will not result in degradation and is consistent with the antidegradation policies. Therefore, this revision is permissible consistent CWA section 303(d)(4)(B).
h. Santa Clara River Estuary and Reaches 3, 5, 6 and 7 Indicator Bacteria TMDL
The 2012 Los Angeles County MS4 Permit incorporated WQBELs for E. coli for MS4 discharges to Santa Clara River Reaches 5, 6, and 7. The WQBELs were applied at the outfalls and Permittees were not allowed any exceedance days. For Los Angeles County Permittees, this Order incorporates the following exceedance days at the outfall for the daily maximum single sample objectives:

Constituent Daily Maximum Single Sample Objectives for Santa Clara River Reaches 5 and above (MPN or cfu)
E. coli 235/100 mL
Location Time Period
Interim Annual Allowable Exceedance
Days of the Single Sample Objectives
Daily
Sampling
Weekly
Sampling
3 Wet and 2
Dry weather
events
Santa Clara
River Reaches
5 and above
Dry Weather
(November 1 to October 31) 17 3 1
Wet Weather
(November 1 to October 31) 61 9 1

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Location Time Period
Final Annual Allowable Exceedance
Days of the Single Sample Objectives
Daily Sampling Weekly
Sampling
Santa Clara River
Reaches 5 and
above
Dry Weather
(November 1 to October 31) 5 1
Wet Weather
(November 1 to October 31) 16 3
The allowable exceedance days applied at the outfalls were erroneously omitted from the 2012 Los Angeles County MS4 Permit. Implementation of allowable exceedance days at the outfall in this permit is less stringent than the previous 2012 Los Angeles County MS4 Permit because Los Angeles County Permittees may exceed the daily maximum single sample objective per the allowable exceedance days as outlined in the above tables without violating the permit. However, allowing exceedance days is consistent with the TMDL and allowed pursuant to CWA section 303(d)(4)(A) for the following reason—when the TMDL was adopted it specifically contemplated application of exceedance days at the outfall in its implementation plan. Chapter 7, section 7-36 of the Basin Plan under the heading “Monitoring to Determine Compliance”, states, “Responsible jurisdictions and agencies shall assess compliance at the outfall monitoring sites identified in the implementation plan.

Compliance shall be based on the allowable number of exceedance days…” (Basin Plan, p. 7-436.) Applying the allowable exceedance days to WQBELs measured at the outfalls is therefore consistent with the assumptions and requirements of the applicable TMDL WLAs and will ensure attainment of the water quality standard. As such, this revision is permissible under CWA section 303(d)(4)(A).

J. Human Right to Water Law
The Order is consistent with Water Code section 106.3 which establishes the policy of the State of California that every human being has the right to safe, clean, affordable, and accessible water adequate for human consumption, cooking, and sanitary purposes. The Order implements Water Code section 106.3 and promotes the State Water Board’s resolution adopting the human right to water as a core value and directing its implementation in Water Board programs and activities (Resolution No. 2016-0010) by requiring receiving waters to meet adopted water quality standards that are designed to protect human health and ensure that water is safe for domestic use and by regulating discharges to minimize loading to attain the highest water quality which is reasonable, considering all demands being made on those waters and the total values involved. (Water Code, sections 13000, 13050, subdivisions (i)-(m), 13240, 13241, 13263; State Water Board Resolution No. 68-16.) The Order includes actions to improve conditions for economically distressed communities and persons experiencing homelessness.

K. Advancing Measures to Mitigate and Adapt to Climate Change The predicted impacts of climate change in Southern California include an increase in temperatures, heightened frequency of extreme weather conditions including extreme precipitation events and drought, along with sea level rise. At the local scale, within urbanized areas, these changes may directly impact groundwater and surface water

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supply; drainage, flooding, and erosion patterns; economically distressed communities; and ecosystems and habitat.

In recognition of the challenges posed by climate change, the State Water Board adopted on March 7, 2017 a resolution that requires a proactive approach to climate change in all State Water Board actions, including drinking water regulation, water quality protection, and financial assistance (Resolution No. 2017-0012). The resolution lays the foundation for a response to climate change that is integrated into all State Water Board actions, by giving direction to the State Water Board divisions and encouraging coordination with the Regional Water Boards. In conjunction with the State Water Board’s Resolution, the Los Angeles Water Board adopted “A Resolution to Prioritize Actions to Adapt to and Mitigate the Impacts of Climate Change on the Los Angeles Region’s Water Resources and Associated Beneficial Uses” (Resolution No.

R18-004) on May 10, 2018. The resolution summarizes the steps taken so far to address the impacts of climate change within the Los Angeles Water Board and lists a series of steps to move forward. These include the identification of potential regulatory adaptation and mitigation measures that could be implemented on a short-term and long-term basis by each of the Los Angeles Water Board’s programs to take into account, and assist in mitigating where possible, the effects of climate change on water resources and associated beneficial uses.

In addition, Executive Order N-10-19, signed on April 29, 2019, directs the California Natural Resources Agency (CNRA), the California Environmental Protection Agency (CalEPA), and the California Department of Food and Agriculture (CDFA) to prepare a water resilience portfolio that meets the needs of California’s communities, economy, and environment, and expand and/or reassess the priorities in the California Water Action Plan. The order directs agencies to prioritize multi-benefit approaches, natural infrastructure, innovation and new technologies, regional approaches, integration across state government, and partnerships across governments.

The Order follows the guiding principles of the State and Los Angeles Water Boards resolutions (No. 2017-0012 and No. R18-004) as well as Executive Order N-10-19 by contributing to an adaptive climate change and water resilience strategy. Through multibenefit regional projects, stormwater and non-stormwater runoff can be captured, infiltrated, and used to mitigate periodic drought conditions, reduce flood hazards and erosion rates, and recharge depleted groundwater aquifers and other water supply sources, all while reducing pollutant loads, maintaining beneficial uses in receiving waters and improving community health.

While not a requirement, to maximize these types of benefits when considering different possible approaches (management practices, locations, etc.) to achieve compliance, permittees should consider climate change offsets. The relevance of long-term implementation measures in the face of a changing climate may be considered, for example, by taking into account the results of regional climate change models in stormwater models used to develop Watershed Management Programs, or by considering BMP vulnerability to climate change when designing mitigation plans.

Overall, implementation of such a strategy has multiple benefits and may contribute to enhancing local water supply, creating drought buffer reserves, and restoring habitat and watershed health.

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L. California Environmental Quality Act (CEQA)
The action to adopt an NPDES permit is exempt from the provisions of Chapter 3 of the California Environmental Quality Act (CEQA) (Public Resources Code, § 21100, et seq.) pursuant to California Water Code section 13389. (County of Los Angeles v. Cal. Water Boards (2006) 143 Cal.App.4th 985.)
M. Advancing Racial Equity
In accordance with the Water Boards’ Racial Equity Initiative, formally launched on August 18, 2020, the Order requires all Permittees to meet water quality standards to protect public health and the environment, thereby benefitting all persons and communities within the Region. The Los Angeles Water Board is committed to developing and implementing policies and programs to advance racial equity and environmental justice so that race can no longer be used to predict life outcomes, and outcomes for all groups are improved.

N. Other Plans, Policies, and Regulations
The Order implements all other applicable federal regulations and State plans, policies, and regulations.

IV. RATIONALE FOR DISCHARGE PROHIBITIONS
A. Non-Stormwater Discharges

1. Regulatory Background
The CWA employs the strategy of prohibiting the discharge of any pollutant from a point source into waters of the United States unless the discharger of the pollutant(s) obtains an NPDES permit pursuant to CWA section 402. The 1987 amendments to the CWA included section 402(p) that specifically addresses NPDES permitting requirements for municipal discharges from MS4s. Section 402(p) prohibits the discharge of pollutants from specified MS4s to waters of the United States except as authorized by an NPDES permit and identifies the substantive standards for MS4 permits. The MS4 permits (1) “shall include a requirement to effectively prohibit non-stormwater discharges into the storm sewers[ ]” and (2) “shall require [i] controls to reduce the discharge of pollutants to the maximum extent practicable, including management practices, control techniques and system, design and engineering methods, and [ii] such other provisions as the Administrator or the State determines appropriate for the control of such pollutants.” (CWA § 402(p)(3)(B)(ii-iii).)
On November 16, 1990, U.S. EPA published regulations to implement the 1987 amendments to the CWA (55 Fed. Reg. 47990 et seq. (Nov. 16, 1990)). The regulations establish minimum requirements for MS4 permits and address both stormwater and non-stormwater discharges from MS4s; however, the minimum requirements for each are significantly different. This is evident from U.S. EPA’s preamble to the stormwater regulations, which states that “Section 402(p)(B)(3) [of the CWA] requires that permits for discharges from municipal separate storm sewers require the municipality to “effectively prohibit” non-stormwater discharges from the municipal storm sewer … Ultimately, such non-stormwater discharges through a municipal separate storm sewer system must either be removed from the system or become subject to an NPDES permit.” (55 Fed.Reg. 47990, 47995

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(Nov. 16, 1990).)
111 U.S. EPA states that MS4 Permittees are to begin to fulfill the “effective prohibition of non-storm water discharges” requirement by: (1) conducting a screening analysis of the MS4 to provide information to develop priorities for a program to detect and remove illicit discharges, (2) implementing a program to detect and remove illicit discharges, or ensure they are covered by a separate NPDES permit, and (3) to control improper disposal into the storm sewer. (40 CFR § 122.26(d)(2)(iv)(B).) These non-stormwater discharges therefore are not subject to the MEP standard. In its precedential decision on the 2012 Los Angeles County MS4 Permit (Order WQ 2015-0075), the State Water Board affirmed that “MEP is not the standard that governs non-storm water discharges.”112

2. Definition of Non-Stormwater
Neither the CWA nor federal regulations specifically define “non-stormwater.” The definition of “non-stormwater” is derived from the definition of “stormwater.” Federal regulations define “storm water” as “storm water runoff, snow melt runoff, and surface runoff and drainage.” (40 CFR § 122.26(b)(13).) While “surface runoff and drainage” is not defined in federal law, U.S. EPA’s preamble to the federal regulations demonstrates that the term is related to precipitation events such as rain and/or snowmelt. (55 Fed.Reg. 47990, 47995-96 (Nov. 16, 1990)). For example, U.S. EPA states:

In response to the comments [on the proposed rule] which requested EPA to define the term ‘storm water’ broadly to include a number of classes of discharges which are not in any way related to precipitation events, EPA believes that this rulemaking is not an appropriate forum for addressing the appropriate regulation under the NPDES program of such non-storm water discharges . . . . Consequently, the final definition of storm water has not been expanded from what was proposed.
(Ibid.) The stormwater regulations themselves identify numerous categories of discharges including landscape irrigation, diverted stream flows, discharges from drinking water supplier sources, foundation drains, air conditioning condensation, irrigation water, springs, water from crawl space pumps, footing drains, lawn watering, individual residential car washing, and street wash water as “nonstormwater.” While these types of discharges may be regulated under stormwater permits, they are not considered stormwater discharges. (40 CFR § 122.26(d)(2)(iv)(B)). U.S. EPA states that, “in general, municipalities will not be held responsible for prohibiting some specific components of discharges or flows … through their municipal separate storm sewer system, even though such components may be considered non-storm water discharges…” (emphasis added).

However, where certain categories of non-stormwater discharges are identified by the Permittee (or the Los Angeles Water Board) as needing to be addressed, they are no longer exempt and become subject to the effective prohibition requirement in CWA section 402(p)(3)(B)(ii). This review of the stormwater regulations and U.S.

EPA’s discussion of the definition of stormwater in its preamble to these regulations strongly supports the interpretation that stormwater includes only precipitationrelated discharges. Therefore, non-precipitation related discharges are not 111 U.S. EPA further states that, “[p]ermits for such [non-storm water] discharges must meet applicable technology-based and water-quality based requirements of Sections 402 and 301 of the CWA.” (55 Fed.

Reg. 47990, 48037 (Nov. 16, 1990)).
112 State Water Board Order WQ 2015-0075, p. 62.

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stormwater discharges and, therefore, are not subject to the MEP standard in CWA section 402(p)(3)(B)(iii). Rather, non-stormwater discharges shall be effectively prohibited pursuant to CWA section 402(p)(3)(B)(ii), as discussed further in the next two sections.

While federal regulations have no definition for “non-stormwater discharges,” “illicit discharges” defined in the regulations is the most closely applicable definition and the terms are often used interchangeably. “Illicit discharge” is defined by U.S. EPA as “any discharge to a municipal separate storm sewer that is not composed entirely of storm water except discharges pursuant to a NPDES permit . . . and discharges resulting from firefighting activities.”113 The program must include among other elements a program to implement and enforce an ordinance, orders or similar means to prevent illicit discharges to the MS4. The program is to address all types of illicit discharges, however the federal regulations specifically identify the following categories of non-stormwater discharges to be addressed where such discharges are identified by the municipality as sources of pollutants to waters of the United States: water line flushing, landscape irrigation, diverted stream flows, rising ground waters, uncontaminated ground water infiltration (as defined at 40 CFR § 35.2005(20)) to separate storm sewers, uncontaminated pumped ground water, discharges from potable water sources, foundation drains, air conditioning condensation, irrigation water, springs, water from crawl space pumps, footing drains, lawn watering, individual residential car washing, flows from riparian habitats and wetlands, dechlorinated swimming pool discharges, and street wash water...”.114 Accordingly, federal regulations require that non-stormwater discharges be controlled if they are a significant source of pollutants and the permitting authority is expected to include permit conditions to prohibit or control specified categories of non-stormwater discharges if they are determined to be a source of pollutants to waters of the United States.

3. Non-Stormwater Regulation
Non-stormwater discharges from the MS4 that are not authorized by separate NPDES permits, nor specifically exempted, are subject to requirements under the NPDES program, including discharge prohibitions, technology-based effluent limitations and water quality-based effluent limitations (40 CFR § 122.44). U.S.

EPA’s preamble to the stormwater regulations also supports the interpretation that regulation of non-stormwater discharges through an MS4 is not limited to the MEP standard in CWA section 402(p)(3)(B)(iii):
“Today’s rule defines the term “illicit discharge” to describe any discharge through a municipal separate storm sewer system that is not composed entirely of storm water and that is not covered by an NPDES permit. Such illicit discharges are not authorized under the Clean Water Act. Section 402(p(3)(B) requires that permits for discharges from municipal separate storm sewers require the municipality to “effectively prohibit” non-storm water discharges from the municipal separate storm sewer…Ultimately, such non-storm water discharges through a municipal separate storm 113 Id., § 122.26(b)(2). The preamble to the regulations states: “Today’s rule defines the term ‘illicit discharge’ to describe any discharge through a municipal separate storm sewer system that is not composed entirely of storm water and that is not covered by an NPDES permit.” (55 Fed. Reg. 47990, 47995 (Nov. 16, 1990)
114 40 CFR § 122.26(d)(2)(iv)(B)(1).