SP20-0002_Staff Report_Attach D- EIR Appx J2-SWQMP — San Marcos City Council, May 10, 2022

Hallmark‐Barham Specific Plan EIR
Technical Appendices

Appendix J.2
SWQMP
City of San Marcos

PRIORITY DEVELOPMENT PROJECT (PDP)

STORM WATER QUALITY MANAGEMENT PLAN (SWQMP)
FOR
943 Barham Drive
[INSERT PERMIT APPLICATION NUMBERS]
943 Barham Drive
San Marcos, CA 92078
ASSESSOR'S PARCEL NUMBER(S):
228-310-01
ENGINEER OF WORK:

PREPARED FOR:

Hall Land Company , Inc.
740 Lomas Santa Fe Drive , Suite 204
Solana Beach, California 92075
(858) 481-3310
PDP SWQMP PREPARED BY:

SB&O, Inc.
3990 Ruffin Rd. Suite 120
San Diego, CA 92123
(858) 560-1141
DATE OF SWQMP:
19-June-2020
PLANS PREPARED BY:

BB&D~
Pi.ANNING (:NG INC.CRlNG St.JFl'VEY1NQ
3990 Ruffin Rd. Suite 120
San Diego, CA 92123
(858) 560-1141
JN 75050.65
City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020
City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020

Page intentionally blank

City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020

TABLE OF CONTENTS

Acronym Sheet
PDP SWQMP Preparer's Certification Page
PDP SWQMP Project Owner's Certification Page
Submittal Record
Project Vicinity Map
FORM I-1 Applicability of Storm Water BMP Requirements
FORM I-2 Project Type Determination Checklist (Standard Project or PDP) FORM I-3B Site Information Checklist for PDPs
FORM I-4 Source Control BMP Checklist for All Development Projects FORM I-5 Site Design BMP Checklist for All Development Projects FORM I-6 Summary of PDP Structural BMPs
Attachment 1: Backup for PDP Pollutant Control BMPs
Attachment 1a: DMA Exhibit
Attachment 1b: Tabular Summary of DMAs and Design Capture Volume Calculations Attachment 1c: Harvest and Use Feasibility Screening (when applicable) Attachment 1d: Categorization of Infiltration Feasibility Condition (when applicable) Attachment 1e: Pollutant Control BMP Design Worksheets / Calculations Attachment 2: Backup for PDP Hydromodification Control Measures Attachment 2a: Hydromodification Management Exhibit
Attachment 2b: Management of Critical Coarse Sediment Yield Areas Attachment 2c: Geomorphic Assessment of Receiving Channels Attachment 2d: Flow Control Facility Design
Attachment 3: Structural BMP Maintenance Plan
Attachment 3a: B Structural BMP Maintenance Thresholds and Actions Attachment 3b: Draft Maintenance Agreement (when applicable) Attachment 4: Copy of Plan Sheets Showing Permanent Storm Water BMPs

City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020

ACRONYMS

APN Assessor's Parcel Number
BMP Best Management Practice
HMP Hydromodification Management Plan
HSG Hydrologic Soil Group
MS4 Municipal Separate Storm Sewer System
N/A Not Applicable
NRCS Natural Resources Conservation Service
PDP Priority Development Project
PE Professional Engineer
SC Source Control
SD Site Design
SDRWQCB San Diego Regional Water Quality Control Bo ard SIC Standard Industrial Classification
SWQMP Storm Water Quality Management Plan

PDP SWQMP PREPARER'S CERTIFICATION PAGE
Project Name: 943 Barham Drive
Permit Application Number: [Insert Permit Application Number]

PREPARER'S CERTIFICATION
I hereby declare that I am the Engineer in Responsible Charge of design of storm water best management practices (BMPs) for this project, and that I have exercised responsible charge over the design of the BMPs as defined in Section 6703 of the Business and Professions Code, and that the design is consistent with the PDP requirements of the City of San Marcos BMP Design Manual, which is a design manual for compliance with local City of San Marcos and regional MS4 Permit (California Regional Water Quality Control Board San Diego Region Order No. R9-2015-0100) requirements for storm water management .

I have read and understand that the [City Engineer] has adopted minimum requirements for managing urban runoff , including storm water, from land development activities, as described in the BMP Design Manual. I certify that this PDP SWQMP has been completed to the best of my ability and accurately reflects the project being proposed and the applicable BMPs proposed to minimize the potentially negative impacts of this project's land development activities on water quality . I understand and acknowledge that the plan check review of this PDP SWQMP by the [City Engineer] is confined to a review and does not relieve me, as the Engineer in Responsible Charge of design of storm water BMPs for this project , of my responsibilities for project design.

Print Name
BB&D~

PLANN ING ENGINEER ING SURVEY ING
3990 Ruffin Road, Suite 120
San Diego , Ca. 92123
B58-560-114 1
B5B-560-B1 57 Fax
19-June-2020
Date
Engineer's Seal:

City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020
City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020

Page intentionally blank

City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020

PDP SWQMP PROJECT OWNER'S CERTIFICATION PAGE

Project Name: 943 Barham Drive
Permit Application Number: [Insert Permit Application Number]

PROJECT OWNER'S CERTIFICATION

This PDP SWQMP has been prepared for HALL LAND COMPANY, INC by SB&O, Inc . PDP SWQMP is intended to comply with the PDP requirements of the City of San Marcos BMP Design Manual, which is a design manual for compliance with local City of San Marcos and regional MS4 Permit (California Regional Water Quality Control Board San Diego Region Order No. R9-2015-0100) requirements for storm water management.

The undersigned, while it owns the subject property , is responsible for the implementation of the provisions of this plan. Once the undersigned trans fers its interests in the property, its successor-i n- interest shall bear the aforementioned responsibili ty to implement the best management practices (BMPs) described within this plan, including ensuri ng on-going operation and maintenance of structural BMPs. A signed copy of this document shall be available on the subject property into perpetuity.

________________________________________________________ Project Owner's Signature

________________________________________________________ Print Name

HALL LAND COMPANY, INC
Company

____________________________
Date

City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020

Page intentionally blank

City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020

SUBMITTAL RECORD

Use this Table to keep a record of submittals of th is PDP SWQMP. Each time the PDP SWQMP is re- submitted, provide the date and status of the project. In column 4 summarize the changes that have been made or indicate if response to plancheck comments is included. When applicable, insert response to plancheck comments behind this page.

Submittal
Number
Date Project Status Summary of Changes
1 19 -Jun -2020 ☒ Preliminary Design/
Planning/ CEQA
☐ Final Design
Initial Submittal
2 ☐ Preliminary Design/
Planning/ CEQA
☐ Final Design

3 ☐ Preliminary Design/
Planning/ CEQA
☐ Final Design

4 ☐ Preliminary Design/
Planning/ CEQA
☐ Final Design

City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020

PROJECT VICINITY MAP

Project Name: 943 Barham Drive
Permit Application Number: [Insert Permit Application Number]

VICINITY MAP

NOT TO SCALE
City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020

Applicability of Storm Water Best Management Practices (BMP) Requirements (Storm Water Intake Form for all Development Permit Applications) For detailed information please visit:
http://www.san-marcos.net/departments/development-services/stormwater/development-planning Form I -1
[March 15, 2016]
Project Identification
Project Name: 943 Barham Drive
Description: Multifamily Residential buildings with approximately 150 attached units with garages and surface parking with Rec Building and Tot Lot.

Permit Application Number (if applicable): [Ins ert Permit Application Number] Date: 19 -Jun -2020 Project Address: 943 Barham Drive
Determination of Requirements
This form is required as part of the City’s application process. The purpose of this form i s to identify potential land development planning storm water requirements that apply to development projects.

Development projects are defined as construction, rehabilitation, redevelopment, or reconstruction of any public or private projects. In addition, the identification of a development project, as it relates to storm water regulations, would truly apply to development and redevelopment activities that have the potential to contact storm water and contribute a source of pollutants, or reduce the natural absorption and infiltration abilities of the land.

To access the BMP Design Manual, Storm Water Quality Management Plan (SWQMP) templates, and other pertinent information related to this program please refer to:
http://www.san-marcos.net/departments/development-services/stormwater/development-planning

Please answer each of the following steps below, starting with Step 1 and progressing through each step until reaching "Stop".

Step Answer Progression
Step 1: Based on the above, Is the project a
"development project" (See definition above)?
See Section 1.3 of the BMP Design Manual for
further guidance if necessary.
☒Yes
Go to Step 2.
☐No Permanent BMP requirements do not apply. No
SWQMP will be required. Provide brief discussion
below.

STOP.

Discussion / justification if the project is not a "development project" (e.g., the project includes only interior remod els within an existing building):

Step 2: Is the project a Standard Project, Priority
Development Project (PDP), or exception to PDP
definitions?

To answer this item, complete Form I-2, Project
Type Determination. See Section 1.4 of the BMP
Design Manual in its entirety for guidance.

In addition to Section 1.4, please refer to the
City’s SWQMP Submittal Requirements form.

☐Standard Project
Only Standard Project requirements apply,
including Standard Project SWQMP. STOP.
☒PDP Standard and PDP requirements apply, including
PDP SWQMP. Go to Step 3 on the following page.
☐ Exception to PDP
definitions
Standard Proje ct requirements apply, and any
additional requirements specific to the type of
project. Provide discussion and list any additional
requirements below. Prepare Standard Project
SWQMP. STOP.

Discussion / justification, and additional requirements for excep tions to PDP definitions, if applicable:

City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020

Form I -1 Page 2 , Form Date: March 15, 2016
Step 3 (PDPs only) . Please answer the list of questions in this section to determine if hydromodification requirements reply to the proposed PDP. Does the project:

Step 3a. Discharge storm water
runoff directly to the Pacific Ocean?
☐Yes STOP . Hydromodification requirements do not apply. ☒No Continue to Step 3b.

Step 3b . Discharge storm water
runoff directly to an enclosed
embayment, not within protected
areas?
☐Yes STOP . Hydromodification requirements do not apply. ☒No Continue to Step 3c.

Step 3c . Discharge storm water
runoff directly to a water storage
reservoir or lake, below spillway or
normal operating level?
☐Yes STOP . Hydromodification requir ements do not apply. ☒No Continue to Step 3d.

Step 3d . Discharge storm water
runoff directly to an area identified in
WMAA?
☐Yes STOP . Hydromodification requirements do not apply. ☒No Hydromodification requirements apply to the project. Go to Step

4. Discussion / justification if hydromodification control requirements do not apply:

Step 4 (PDPs subject to
hydromodification control
requirements only). Does protection
of critical coarse sediment yield areas
apply based on review of WMAA
Potential Critical Coarse Sediment
Yield Area Map?
See Section 6.2 of the BMP Design
Manual for guidance.

☒Yes
Management measures required for protection of critical coarse sediment yield areas (Chapter 6.2).

Stop.
☐No Management measures not required for protection of critical coarse sediment yield areas.

Provide brief discussion below.

Stop.

City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020

Project Type Determination Checklist Form I-2
[March 15, 2016]
Project Information
Project Name/Description: 943 Barham Drive
Permit Application Number (if applicable): [Insert Permit Application Number]
Date: 19-Jun-2020
Project Address: 943 Barham Drive
Project Type Determination: Standard Project or Priority Development Project (PDP) The project is (select one): ☒ New Development ☐Redevelopment The total proposed newly created or replaced impervious area is: 265,617 ft2 (_6.098) acres Is the project in any of the following categories, (a) through (f)? ☒
Yes
☐
No
(a) New development projects that create 10,000 square feet or more of impervious surfaces (collectively over the entire project site). This includes commercial, industrial, residential, mixed-use, and public development projects on public or private land.
☐
Yes
☒
No
(b) Redevelopment projects that create and/or replace 5,000 square feet or more of impervious surface (collectively over the entire project site on an existing site of 10,000 square feet or more of impervious surfaces). This includes commercial, industrial, residential, mixed-use, and public development projects on public or private land.
☐
Yes
☒
No
(c) New and redevelopment projects that create and/or replace 5,000 square feet or more of impervious surface (collectively over the entire project site), and support one or more of the following uses:
(i) Restaurants. This category is defined as a facility that sells prepared foods and drinks for consumption, including stationary lunch counters and refreshment stands selling prepared foods and drinks for immediate consumption (Standard Industrial Classification (SIC) code 5812). (ii) Hillside development projects. This category includes development on any natural slope that is twenty-five percent or greater.
(iii) Parking lots. This category is defined as a land area or facility for the temporary parking or storage of motor vehicles used personally, for business, or for commerce.
(iv) Streets, roads, highways, freeways, and driveways. This category is defined as any paved impervious surface used for the transportation of automobiles, trucks, motorcycles, and other vehicles.

I
I
City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020

Form I -2 Page 2 , Form Date: March 15, 2016
☐
Yes
☒
No
(d) New or redevelopment projects that create and/ or replace 2,500 square feet or more of impervious surface (collectively over the entire project site), and discharging directly to an Environmentally Sensitive Area (ESA). “Discharging directly to” includes flow that is conveyed overland a distance of 200 feet or less from the project to the ESA, or conveyed in a pipe or open channel any distance as an isolated flow from the project to the ESA (i.e. not commingled with flows from adjacent lands).

Note: ESAs are areas that include but are not limited to all Clean Water Act Section 303(d) impaired water bodies; areas designated as Areas of Special Biological Significance by the State Water Board and San Diego Water Board; State Water Quality Protected Areas; water bodies designated with the RARE beneficial use by the State Water Board and San Diego Water Board; and any other equivalent environmentally sensitive areas which have been identified by the Co-permittees. See BMP Design Manual Section 1.4.2 for additional guidance.
☐
Yes
☒
No
(e) New development projects , or redevelopment projects that create and/or replace 5,000 square feet or more of impervious surface, that support one or more of the following uses:
(i) Automotive repair shops. This category is defined as a facility that is categorized in any one of the following SIC codes: 5013, 5014, 5541, 7532- 7534, or 7536-7539.
(ii) Retail gasoline outlets (RGOs). This category includes RGOs that meet the following criteria: (a) 5,000 square feet or more or (b) a projected Average Daily Traffic (ADT) of 100 or more vehicles per day.
☐
Yes
☒
No
(f) New or redevelopment projects that result in the disturbance of one or more acres of land and are expected to generate pollutants post construction.

Note: See BMP Design Manual Section 1.4.2 for additional guidance.

Does the project meet the definition of one or more of the Priority Development Project categories (a) through (f) listed above?
☐No – the project is not a Priority Development Project (Standard Project). ☒Yes – the project is a Priority Development Project (PDP).

The fol lowing is for redevelopment PDPs only :

The area of existing (pre-project) impervious area at the project site is: ________ ft 2 (A)
The total proposed newly created or replaced impervious area is ________ ft 2 (B) Percent impervious surface created or replaced (B/A)*100: _______% The percent impervious surface created or replaced is (select one based on the above calculation):
less than or equal to fifty percent (50%) – only new impervious areas are considered PDP OR
greater than fifty percent (50%) – the entire project site is a PDP

City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020

Site Information Checklist
For PDPs
Form I-3B (PDPs)
[March 15, 2016]
Project Summary Information
Project Name: 943 Barham Drive
Project Address 943 Barham Drive
San Marcos CA 92078

Assessor's Parcel Number(s) (APN(s)) 228 -310 -01
Permit Application Number [Insert Permit Application Number] Project Hydrologic Unit Select One:
☐ Santa Margarita 902
☐ San Luis Rey 903
☒ Carlsbad 904
☐ San Dieguito 905
☐ Penasquitos 906

Project Watershed
(Complete Hydrologic Unit, Area, and Subarea
Name with Numeric Identifier)
San Marcos 904.5
Parcel Area
(total area of Assessor's Parcel(s) associated
with the project)

__10.00__ Acres (_435,600 Square Feet)
Area to be Disturbed by the Project
(Project Area)

__9.0884__ Acres ( 395,891 Square Feet)
Project Proposed Impervious Area
(subset of Project Area)

__6.098_ Acres ( 265,617 Square Feet)
Project Proposed Pervious Area
(subset of Project Area)

_2.9904_ Acres (130,274 Square Feet)
Note: Proposed Impervious Area + Proposed Pervious Area = Area to be Disturbed by the Project.

This may be less than the Parcel Area.

City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020

Form I-3B Page 2 of 10 , Form Date: March 15 , 201 6
Descrip tion of Existing Site Condition
Current Status of the Site (select all that apply):
☐Existing development ☐Previously graded but not built out ☐Agricultural or other non-impervious use
☒Vacant, undeveloped/natural

Description / Additional Information:

Existing Land Cover Includes (select all that apply):
☒Vegetative Cover
☐Non-Vegetated Pervious Areas
☒Impervious Areas

Description / Additional Information:

Underlying Soil be longs to Hydrologic Soil Group (select all that apply):
☐NRCS Type A
☐NRCS Type B
☐NRCS Type C
☒NRCS Type D

Approximate Depth to Groundw ater:
☐Groundwater Depth < 5 feet
☐5 feet < Groundwater Depth < 10 feet
☐10 feet < Groundwater Depth < 20 feet
☒Groundwater Depth > 20 feet

Existing Natural Hydrologic Features (select all that apply):
☐ Watercourses
☐ Seeps
☐ Springs
☐ Wetlands
☒ None

Description / Additional Information:

City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020

Form I-3B Page 3 of 10 , Form Date: March 15, 201 6
Description of Existing Site Drainage Patterns
How is storm water runoff conveyed from the site? At a minimum, this description should answer:
(1) whether existing drainage conveyance is natural or urban; (2) Is runoff from offsite conveyed through the site? if yes, quantify all offsite drainage areas, design flows, and locations where offsite flows enter the project site, and summarize how such flows are conveyed through the site;
(3)Provide details regarding existing project site drainage conveyance network, including any existing storm drains, concrete channels, swales, detention facilities, storm water treatment facilities, natural or constructed channels; and
(4) Identify all discharge locations from the existing project site along with a summary of conveyance system size and capacity for each of the discharge locations. Provide summary of the pre-project drainage areas and design flows to each of the existing runoff discharge locations.

Describe existing site drainage patterns:

1. The existing site is vacant and includes a hillside along the southern limits. Drainage is “natural” and generally overland toward the Barham Road frontage.

2. Drainage patterns are generally southeast to northw est and includes run-on from the hillside above the site.

3. No site drainage facilities. The majority of site runoff is directed overland to the Barham gutter. A small depression is near the northwest corner of the site.

4. An interim storm drain riser is located near the no rtheast corner of the site and is connected to the public storm drain in Barham Road (MS-4).

City of San Marcos storm drain plan IP 4729 Sheet 39B

Interim 18” RCP Storm Drain @ 0.39% Interim Capacity = 10.2 cfs

Ultimate Storm Drain 48” RCP @ 0.66% Q100 = 117.4 cfs

City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020

Form I-3B Page 4 of 10 , Form Date: March 15, 2016
Description of Proposed Site Development
Project Description / Proposed Land Use and/or Activities:

Multifamily residential buildings with private streets and surface parking, with a recreation center and tot lot.

List/describe proposed impervious features of the project (e.g., buildings, roadways, parking lots, courtyards, athletic courts, other impervious features):

Roof, private driveways and parking lots
Concrete walkways joining building and parking

List/describe proposed pervious features of the project (e.g., landscape areas):

Landscape areas
Manufactured slopes
Natural slopes located south of the development area

Does the project include grading and changes to site topography? ☒Yes
☐No

Description / Additional Information:

Site grading will include fill placement to raise the site above Barham Road, cut slopes along the rear slope limits.

City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020

Form I-3B Page 5 of 10 , Form Date: March 15, 2016
Description of Proposed Site Drainage Patterns
Does the project include changes to site drainage (e.g., installation of new storm water conveyance systems)?
☒Yes
☐No

If yes, provide details regarding the proposed project site drainage conveyance network, including storm drains, concrete channels, swales, detention facilities, storm water treatment facilities, natural or constructed channels, and the method for conveying offsite flows through or around the proposed project site. Identify all discharge locations from the proposed project site along with a summary of the conveyance system size and capacity for each of the discharge locations. Provide a summary of pre- and post-project drainage areas and design flows to each of the runoff discharge locations. Reference the drainage study for detailed calculations.

Describe proposed site drainage patterns::

Bypass ditches and storm drain inlets to intercept natural and manufactured slopes located southerly and westerly of the development area. A concrete ditch will convey flows along the westerly boundary to Barham.

Private driveways, swales and gutters will direct runoff to the onsite private storm drain system which is directed to the combination basin (treatment, HMP and detention) at the northwest corner of the project. Basin discharge will be to the existing storm drain.

Driveway entries and frontage slopes will discharge to the existing Barham gutter, which will continue westerly to the existing curb inlet near the adjacent driveway.

See Drainage Report for detention analysis and Existing vs Post Development discharge.

City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020

Form I-3B Page 6 of 10 , Form Date: March 15, 2016
Identify whether any of the following features, activities, and/or pollutant source areas will be present (select all that apply):

☒ On-site storm drain inlets
☐ Interior floor drains and elevator shaft sump pumps
☐ Interior parking garages
☒ Need for future indoor & structural pest control
☒ Landscape/Outdoor Pesticide Use
☒ Pools, spas, ponds, decorative fountains, and other water features ☐ Food service
☒ Refuse areas
☐ Industrial processes
☐ Outdoor storage of equipment or materials
☐ Vehicle and Equipment Cleaning
☐ Vehicle/Equipment Repair and Maintenance
☐ Fuel Dispensing Areas
☐ Loading Docks
☒ Fire Sprinkler Test Water
☐ Miscellaneous Drain or Wash Water
☒ Plazas, sidewalks, and parking lots

Description / Additional Information:

City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020

Form I-3B Page 7 of 10 , Form Date: March 15, 2016
Identification and Narrative of Receiving Water and Poll utants of Concern Describe flow path of storm water from the project site discharge location(s), through urban storm conveyance systems as applicable, to receiving creeks, rivers, and lagoons as applicable, and ultimate discharge to the Pacific Ocean (or bay, lagoon, lake or reservoir, as applicable):

Barham Drive Storm Drain (MS-4) to San Marcos Creek (passing through Lake San Marcos) to Batiquitos Lagoon (Inner).

List any 303(d) impaired water bodies within the path of storm water from the project s ite to the Pacific Ocean (or bay, lagoon, lake or reservoir, as applicable), identify the pollutant(s)/stressor(s) causing impairment, and identify any TMDLs and/or Highest Priority Pollutants from the WQIP for the impaired water bodies:
303(d) Impaired Water Body Pollutant(s)/Stressor(s)
TMDLs / WQIP Highest Priority
Pollutant
San Marcos Creek Benthic Community Effects,
Indicator Bacteria, Nutrients &
Metals
Nutrients
Upper San Marcos Creek
Table 8 of WQIP
San Marcos Lake Nutrients, Metals Nutrients
Upper San Marcos Creek
Table 8 of WQIP
Batiquitos Lagoon
Identification of Project Site Pollutants*
*Identification of project site pollutants is only required if flow-thru treatment BMPs are implemented onsite in lieu of retention or biofiltration BMPs (note the project must also participate in an alternative compliance program unless prior lawful approval to meet earlier PDP requirements is demonstrated)
Identify pollutants expected from the project site based on all proposed use(s) of the site (see BMP Design Manual Appendix B.6):

Pollutant
Not Applicable to the
Project Site
Expected from the
Project Site
Also a Receiving Water
Pollutant of Concern
Sediment
Nutrients
Heavy Metals
Organic Compounds
Trash & Debris
Oxygen Demanding
Substances
Oil & Grease
Bacteria & Viruses
Pesticides
City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020

Form I-3B Page 8 of 10 , Form Date: March 15, 2016
Hydromodification Management Requirements
Do hydromodification management requirements apply (see Section 1.6 of the manual)? ☒Yes, hydromodification management flow control structural BMPs required. ☐No, the project will discharge runoff directly to existing underground storm drains discharging directly to water storage reservoirs, lakes, enclosed embayments, or the Pacific Ocean. ☐No, the project will discharge runoff directly to conveyance channels whose bed and bank are concrete-lined all the way from the point of discharge to water storage reservoirs, lakes, enclosed embayments, or the Pacific Ocean.
☐No, the project will discharge runoff directly to an area identified as appropriate for an exemption by the WMAA for the watershed in which the project resides.

Description / Additional Information (to be provided if a ‘No’ answer has been selected above):

Project will discharge runoff to storm drains located on the south west corner of the site.

Critical Coarse Sediment Yield Area s*
*This Section only required if hydromodification management requirements apply Based on the maps provided within the WMAA, do potential critical coarse sediment yield areas exist within the project drainage boundaries?
☐Yes
☒No, no critical coarse sediment yield areas to be protected based on WMAA maps

If yes, have any of the optional analyses presented in Section 6.2 of the manual been performed? ☐6.2.1 Verification of GLUs Onsite
☐6.2.2 Downstream Systems Sensitivity to Coarse Sediment ☐6.2.3 Optional Additional Analysis of Potential Critical Coarse Sediment Yield Areas Onsite ☐No optional analyses were performed; the project will avoid critical coarse sediment yield areas identified based on WMAA maps

If optional analyses were performed, what is the final result? ☐No critical coarse sediment yield areas to be protected based on verification of GLUs onsite. ☐Critical coarse sediment yield areas exist but additional analysis has determined that protection is not required. Documentation attached in Attachment 8 of the SWQMP. ☐Critical coarse sediment yield areas exist and require protection. The project will implement management measures described in Sections 6.2.4 and 6.2.5 as applicable, and the areas are identified on the SWQMP Exhibit.

Discussion / Additional Information:

PCCSYA area are plotted upstream of the site. A bypass system will intercept and convey runoff past the site basin.

City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020

Form I-3B Page 9 of 10 , Form Date: March 15, 2016
Flow Control for Post -Project Runoff*
*This Section only required if hydromodification management requirements apply List and describe point(s) of compliance (POCs) for flow co ntrol for hydromodification management (see Section 6.3.1). For each POC, provide a POC identification name or number correlating to the project’s HMP Exhibit and a receiving channel identification name or number correlating to the project’s HMP Exhibit.

Single POC at the discharge of the water quality/HMP/Detention basin.

SEE DMA EXHIBIT

Has a geomorphic assessment been performed for the receiving channel(s)? ☒No, the low flow threshold is 0.1Q2 (default low flow threshold) ☐Yes, the result is the low flow threshold is 0.1Q2
☐Yes, the result is the low flow threshold is 0.3Q2
☐Yes, the result is the low flow threshold is 0.5Q2

If a geomorphic assessment has been performed, provide title, date, and preparer:

Discussion / Additional Information: (optional)

City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020

Form I-3B Page 10 of 10 , Form Date: March 15, 2016
Other Site Requirements and Constraints
When applicable, list other site requirements or constraints that will influence storm water management design, such as zoning requirements including setbacks and open space, or local codes governing minimum street width, sidewalk construction, allowable pavement types, and drainage requirements.

Limited downstream storm drain capacity & depth (interim condition).

Steep slopes south (uphill) of the development area.

Optional Additional Information or Continuation of Previous Sections As Needed This space provided for additional information or continuation of information from pr evious sections as needed.

City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020

Source Control BMP Checklist
for All Development Projects
(Standard Projects and Priority Development Projects)
Form I-4
[March 15, 2016]
Project Identification
Project Name 943 Barham Drive
Permit Application Number [Insert Permit Application Number] Source Control BMPs
All development projects must implement source control BMPs SC-1 through SC-6 where applicable and feasible. See Chapter 4 and Appendix E of the Model BMP Design Manual for information to implement source control BMPs shown in this checklist.

Answer each category below pursuant to the following.
• "Yes" means the project will implement the source control BMP as described in Chapter 4 and/or Appendix E of the Model BMP Design Manual. Discussion / justification is not required. • "No" means the BMP is applicable to the project but it is not feasible to implement. Discussion / justification must be provided.
• "N/A" means the BMP is not applicable at the project site because the project does not include the feature that is addressed by the BMP (e.g., the project has no outdoor materials storage areas).

Discussion / justification may be provided.

Source Control Requirement Applied?
SC-1 Prevention of Illicit Discharges into the MS4 ☒ Yes ☐ No ☐ N/A Discussion / justification if SC-1 not implemented:

SC-2 Storm Drain Stenciling or Signage ☒ Yes ☐ No ☐ N/A Discussion / justification if SC-2 not implemented:

SC-3 Protect Outdoor Materials Storage Areas from Rainfall, Run-On, Runoff, and Wind Dispersal
☐ Yes ☐ No ☒ N/A
Discussion / justification if SC-3 not implemented:

SC-4 Protect Materials Stored in Outdoor Work Areas from Rainfall, Run-On, Runoff, and Wind Dispersal
☐ Yes ☐ No ☒ N/A
Discussion / justification if SC-4 not implemented:

I
I I I
I I I
I I I
I I I
City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020

Form I -4 Page 2 of 2 , Form Date: March 15, 2016
Source Control Requirement Applied?
SC -5 Protect Trash Storage Areas from Rainfall, Run -On, Runoff, and Wind Dispersal
☒ Yes ☐ No ☐ N/A
Discussion / just ification if SC -5 not implemented:

SC -6 Additional BMPs Based on Potential Sources of Runoff Pollutants (must answer for each source listed below)
On-site storm drain inlets
Interior floor drains and elevator shaft sump pumps
Interior parking garages
Need for future indoor & structural pest control
Landscape/Outdoor Pesticide Use
Pools, spas, ponds, decorative fountains, and other water features Food service
Refuse areas
Industrial processes
Outdoor storage of equipment or materials
Vehicle and Equipment Cleaning
Vehicle/Equipment Repair and Maintenance
Fuel Dispensing Areas
Loading Docks
Fire Sprinkler Test Water
Miscellaneous Drain or Wash Water
Plazas, sidewalks, and parking lots

Yes

Yes
Yes
Yes

Yes

N/A
N/A

N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A

N/A

Discussion / justification if SC -6 not implemented. Clearly identify which sources of runoff pollutants are discussed. Justification must be provided for all "No" answers shown above.

City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020

Site Design BMP Checklist
for All Development Projects
(Standard Projects and Priority Development Projects)
Form I-5
[March 15, 2016]
Project Identification
Project Name 943 Barham Drive
Permit Application Number [Insert Permit Application Number] Site Design BMPs
All development projects must implement site design BMPs SD-1 through SD-8 where applicable and feasible. See Chapter 4 and Appendix E of the Model BMP Design Manual for information to implement site design BMPs shown in this checklist.

Answer each category below pursuant to the following.
• "Yes" means the project will implement the site design BMP as described in Chapter 4 and/or Appendix E of the Model BMP Design Manual. Discussion / justification is not required. • "No" means the BMP is applicable to the project but it is not feasible to implement. Discussion / justification must be provided.
• "N/A" means the BMP is not applicable at the project site because the project does not include the feature that is addressed by the BMP (e.g., the project site has no existing natural areas to conserve).

Discussion / justification may be provided.

Site Design Requirement Applied?
SD-1 Maintain Natural Drainage Pathways and Hydrologic Features ☐ Yes ☐ No ☒ N/A Discussion / justification if SD-1 not implemented:

SD-2 Conserve Natural Areas, Soils, and Vegetation ☒ Yes ☐ No ☐ N/A Discussion / justification if SD-2 not implemented:

Preserve steep hillside.

SD-3 Minimize Impervious Area ☒ Yes ☐ No ☐ N/A
Discussion / justification if SD-3 not implemented:

Multi-story buildings with parking garages, minimum private improvement width.

SD-4 Minimize Soil Compaction ☐ Yes ☒ No ☐ N/A
Discussion / justification if SD-4 not implemented:

Not appropriate for pervious areas onsite.

SD-5 Impervious Area Dispersion ☐ Yes ☒ No ☐ N/A
Discussion / justification if SD-5 not implemented:

Limited pervious lengths or areas.

I
I I I
I I I
I I I
I I I
I I I
City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020

Form I-5 Page 2 of 2, Form Date: March 15, 2016
Site Design Requirement Applied?
SD-6 Runoff Collection ☒ Yes ☐ No ☐ N/A
Discussion / justification if SD-6 not implemented:

Multiple private inlet to reduce length of runoff. Bypass storm drain.

SD-7 Landscaping with Native or Drought Tolerant Species ☒ Yes ☐ No ☐ N/A Discussion / justification if SD-7 not implemented:

SD-8 Harvesting and Using Precipitation ☐ Yes ☒ No ☐ N/A Discussion / justification if SD-8 not implemented:

Not enough landscape area or toilet demand to justify rainwater harvesting.

I
I I I
I I I
I I I
City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020

Summary of PDP Structural BMPs Form I-6 (PDPs)
[March 15, 2016]
Project Identification
Project Name 943 Barham Drive
Permit Application Number [Insert Permit Application Number] PDP Structural BMPs
All PDPs must implement structural BMPs for storm water pollutant control (see Chapter 5 of the BMP Design Manual). Selection of PDP structural BMPs for storm water pollutant control must be based on the selection process described in Chapter 5. PDPs subject to hydromodification management requirements must also implement structural BMPs for flow control for hydromodification management (see Chapter 6 of the BMP Design Manual). Both storm water pollutant control and flow control for hydromodification management can be achieved within the same structural BMP(s).

PDP structural BMPs must be verified by the local jurisdiction at the completion of construction. This may include requiring the project owner or project owner's representative and engineer of record to certify construction of the structural BMPs (see Section 1.12 of the BMP Design Manual). PDP structural BMPs must be maintained into perpetuity, and the local jurisdiction must confirm the maintenance (see Section 7 of the BMP Design Manual).

Use this form to provide narrative description of the general strategy for structural BMP implementation at the project site in the box below. Then complete the PDP structural BMP summary information sheet (page 3 of this form) for each structural BMP within the project (copy the BMP summary information page as many times as needed to provide summary information for each individual structural BMP).

Describe the general strategy for structural BMP implementation at the site. This information must describe how the steps for selecting and designing storm water pollutant control BMPs presented in Section 5.1 of the BMP Design Manual were followed, and the results (type of BMPs selected). For projects requiring hydromodification flow control BMPs, indicate whether pollutant control and flow control BMPs are integrated or separate.

Infiltration at the project site indicates poor infiltration rates, with a recommendation for No Infiltration C
ondition per Geocon, Inc report dated 6/17,2020. Harvest and re-use is not feasible.

O
ffsite and hillside flows are bypassed around the site to avoid the treatment/HMP/detention facility.

A combination treatment/HMP/detention facility will be used for the majority of the developed runoff.

San Marcos Creek is a 303(d) listed water body impaired by nutrient pollutants sources. Nutrient Sensitive Media will be used in the Biofiltration (BF-2) basin with will be used to provide treatment.

The City of San Marcos does not allow treatment facilities in the public right-of-way. Runoff from the driveways, frontage slopes and the existing Barham Road improvements will continue westerly to the existing curb inlet at the church driveway. Street trees will be used at the driveway to intercept and provide treatment.

All 3 of the drainage system will discharge to the existing public storm drain (MS-4) in Barham Road. (Continue on page 2 as necessary.)

I
City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020

Form I -6 Page 2 of X , Form Date: March 15, 2016
(Page reserved for continuation of description of general strat egy for structural BMP implementation at the site)
(Continued from page 1)

City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020

Form I -6 Page 3 of X (Copy as many as needed) Form Date: March 15, 2016 Structural BMP Summary Information
(Copy this page as needed to provide information for each individual proposed structural BMP) Structural BMP ID No. BMP-1 & HMP-1
Construction Plan Sheet No.

Type of structural BMP:
Retention by harvest and use (HU-1)
Retention by infiltration basin (INF-1)
Retention by bioretention (INF-2)
Retention by permeable pavement (INF-3)
Partial retention by biofiltration with partial retention (PR-1) ☐ Biofiltration (BF-1)
☒ Biofiltration with Nutrient Sensitive Media Design (BF-2) Proprietary Biofiltration (BF-3) meeting all requirements of Appendix F Flow-thru treatment control with prior lawful approval to meet earlier PDP requirements (provide BMP type/description in discussion section below)
Flow-thru treatment control included as pre-treatment/forebay for an onsite retention or biofiltration BMP (provide BMP type/description and indicate which onsite retention or biofiltration BMP it serves in discussion section below)
Flow-thru treatment control with alternative compliance (provide BMP type/description in discussion section below)
☒ Detention pond or vault for hydromodification management Other (describe in discussion section below)

Purpose:
Pollutant control only
Hydromodification control only
☒ Combined pollutant control and hydromodification control Pre-treatment/forebay for another structural BMP
Other (describe in discussion section below)

Who will certify construction of this BMP?
Provide name and contact information for the
party responsible to sign BMP verification forms if
required by the [City Engineer] (See Section 1.12 of
the BMP Design Manual)
Engineer of Work
Who will be the final owner of this BMP?

HOA
Who will maintain this BMP into perpetuity?

HOA
What is the funding mechanism for maintenance?

HOA

City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020

Form I -6 Page 4 of X (Copy as many as needed) , Form Date: March 15, 2016 Structural BMP ID No. HMP-1 & BMP-1
Construction Plan Sheet No. See DMA Exhibit
Discussion (as needed):

Biofiltration basin (BF-2) with additional underground storage to provide HMP controls. Additional surface storage will provide attenuation for larger storm events.

City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020

ATTACHMENT 1

BACKUP FOR PDP POLLUTANT CONTROL BMPS

This is the cover sheet for Attachment 1.

Indicate which Items are Included behind this cover sheet:

Attachment
Sequence
Contents Checklist
Attachment 1a DMA Exhibit ( Required )

See DMA Exhibit Checklist on the back of
this Attachment cover sheet.

Included

Attachment 1b Tabular Summary of DMAs Showing DMA
ID matching DMA Exhibit, DMA Area, and
DMA Type (Required)*

*Provide table in this Attachment OR on
DMA Exhibit in Attachment 1a

☐ Included on DMA Exhibit in
Attachment 1a
☒ Included as Attachment 1b, separate
from DMA Exhibit

Attachment 1c Form I -7, Harvest and Use Feasibility
Screening Checklist (Required unless the
entire project will use infiltration BMPs)

Refer to Appendix B.3-1 of the BMP
Design Manual to complete Form I-7.

☒ Included
☐ Not included because the entire
project will use infiltration BMPs

Attachment 1d Form I -8, Categorization of Infiltration Feasibility Condition (Required unless
the project will use harvest and use
BMPs)

Refer to Appendices C and D of the BMP
Design Manual to complete Form I-8.

☒ Included
☐ Not included because the entire
project will use harvest and use BMPs

Attachment 1e Pollutant Control BMP Design
Worksheets / Calculations (Required)

Refer to Appendices B and E of the BMP
Design Manual for structural pollutant
control BMP design guidelines

☒ Included

City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020

Use this checklist to ensure the required information has been included on the DMA Exhibit:

The DMA Exhibit must identify:

Underlying hydrologic soil group
Approximate depth to groundwater
Existing natural hydrologic features ( watercourses, seeps, springs, wetlands) Critical coarse sediment yield areas to be protected
Existing topography and impervious areas
Existing and proposed site drainage network and connections to drainage offsite Proposed demolition
Proposed grading
Proposed impervious features
Proposed design features and surface treatments used to minimize imperviousness Drainage management area (DMA) boundaries, DMA ID numbers, and DMA areas (square footage or acreage), and DMA type (i.e., drains to BMP, self-retaining, or self-mitigating) Potential pollutant source areas and corresponding required source controls (see Chapter 4, Appendix E.1, and Form I-3B)
Structural BMPs (identify location, type of BMP, and size/detail)

~
• I
p, BUILDING -~---~~~~~----,--~-~~~----,.~~-~---~~~--~-~~~-~-~-~~~-~--~~~---~-~~~~-~-~~~---~-~~---~-~~~--~- -~ 6_9_ ,_6_0 S._G.
-------
f"!'ROPO
G'ROUN
,--..1._ "'!"1~
I -.....c._ 18" MIN. EMBEDM -
-+---+--+--i-~=-=-=-~r~r~11=1I1r:xANCROff) E:J(IST._G OUND} =+--c~-+-+-+- '-, --+---+-+-+----+-+--+---+--t-+-+-+--- ::-:b..l

BIOFILTRATION DETAIL NOTES
[II
0 PLAN11NG.
30 MIL P. V.C. LINER. ALL JOINTS TO BE SEALED W7111 12" MIN. OVERLAP.

SEAL ALL P£N£TRA 1/0NS.
[Ij 6" SLOTTE:D P. V.C. SUBDRAIN (ASTM D-3034), 3" MIN. FROM BOTTOM. 0 OU11ET CONTROL STRUC1UR£ W7111 GRATED TOP.
@) OR/RC£ PLATE.

OU1l.£T PIP£.

SUBDRAIN CL£ANOUT PER SDRSD SC-01. RIM = F.G. + 0.6'
INSTALL WELL AGED SHREDDED HARDWOOD MULCH 111AT HAS BEEN STOCKPILED OR STORED FOR AT LEAST 12 MON111S. MULCH MUST BE NON-FLOA 1/NG.
r;;, RL TER COURSE TO BE 3" CLEAN AND WASHED SAND ( ASTM NO. 33) ~ OVER 3" LA YER OF ASTM NO. 8 STONE.
[!Qj SOIL MEDIA, INRL TRA 1/0N = (BSM SPEC/RCA 1/0N PER APPENDIX G OF COUNTY OF SAN DIEGO LI.D. HANDBOOK JUN£ 2014)
PER COUNTY OF SAN O/£GO L.I.D. HANDBOOK:

SANDY LOAM BSM
COMPOS/1/0N SAND SAND I SILT I CLAY COMPOST
VOLUME 65% 20% 15%
WEIGHT 75-80% I 10% MAX. I 3% MAX. 9% MAX.1
9% COMPOST BY WEIGHT R£5UL TS IN APPROX/MA TEL Y 5:f ORGANIC MA TTE:R BY WEIGHT.

COMPLY W7111 NUTRIENT 5£N5l11VE' 50/L MEDIA SPEC/RCA TION5. \
/
/\
/
6 .1
[j] AGGR£GA TE STORAGE LA YER ASTM NO. 57 ROCK.
[gJ
~
2-SACK SLURRY BACKRLL AROUND STORM DRAIN LIN£, PIP£ ZONE.

SLURRY BACKRLL TO START AT STORM DRAIN BOX AND EXTEND AT LEAST 5 FEET BEYOND SLOP£ FACE.

SEAL PVC LINER AROUND PIPES:

US£ A PIP£ BOOT AND PVC SKIRT TO SEAL ALL LINER P£N£TRA 1/0NS FOR PIPES. PVC SKIRT SHOULD BE SEALED TO 111£ PARENT LINER PER MANUFAC1UR£R'5 R£COMM£NDA 1/0NS (TYPICALLY A WEDGE WELDER). 111£ PIP£ BOOT SLEEVE' SHOULD 8£ A TT ACHED TO 111£ PIP£ USING Bum TAP£ AND STAINLESS STEEL BAND CLAMP.

ADJUSTED
AREA
(SF)

SURFACE AREA SURFACE AREA
OMA
NO
A4
AS
A
SITE
f-2
f-3
f-4
f-5
f-6
f-7
TOTALS

TOTAL AREA
/SF)
1,289
20,388
372,553
109,244
72,898
10,424
20,221
11,265
6,212
B,2B5
31,354
642,455

IMPERVIOUS
(SF)
1,289
1,019
265,617
28,219
293,836

JMPERVIOUS
{%)

PERVIOUS
(SF)
DCV
(CF)
100% 1,160 60
5% 19,368 6,728 348
71% 106,936 265,177 13,701
0% 109,244
0% 72,898
0% 10,424
0% 20,221
0% 11,265
0% 6,212
0% B,285
90% 3,135

45. 7% 348,619
REQUIRED*
(SF)
35 202

PROVIDED
(SF)

BMP TYPE/STANDARD
TW3

EAST DRIVEWAY

BARHAM SLOPE

BYPASS DITCH & STORM DRAIN

BYPASS DITCH & STORM DRAIN
BYPA.SS DITCH & STORM DRAIN

BYPASS DITCH & STORM DRAIN

EXISTING BARHAM PAVING
BMP
ID

TREE WELL

DE MIN/MIS

SELF-TREATING

SELF-TREAT/NG
DlfA AND Hlf P EXHIBIT FOR,

BARHAM DRIVE
I
•
/ )
. /
I 1
I /
I /
/ ci;' I
/ ~ / . ~ . I-.:::::_ 1
•
I
@ 1
• • I
I ;
> \> \
' ' ' '
I
I
I
I
I
• • \
;,ii
\
\
'
• /
i
• •
.15 [
20 r I
' 11 I
\ / I "f5lij}
I \ I j i
i' I\ I I \ I :

I \\\c jl
' : II I \ I •
\ I 1
I I
1 • • •
I
•
\ 1 :

I )i .--'-J:' +t----t---r· EXIST. I lff- ,. / I DRAIN
I I f \
I
\
STORM
(MS-4)
•
' •
/ I\ -tttt -t--t,Wf-~t __ \-\ ---k-1,,, -i-l--+---'-' CATCH BASIN

AND DITCH
' I_
'"/ I '
I
I
I
I
I
I
'
, /I
\J I
I I ,
I ii

I I I I
I •
I • •
• •
i
•
• I
I
,,--..J i : ◄
646.5 19 : I 1
I /
POC-1 PROPOSED

CLEANOUT
~ / s.o.\°t) /i!I, 1 j' j / ,.,--..,_ I
. .

I /
I
I
I \
I I I
I
I
648.5 T.C. 18
647.0 [
r, w.s.
\
, I
•
•
•
I
i I
I
' .

I (
" - \
; )
•
. I
\ ;
• I
I
I
•
'
.
•
' ' I
I
/
Ii
A-1

0.1117
I \
,\
•
I
(
i
TW2 AND
A-3

0.1018
\
A-5

0.0349
~
I
I d:

C/j I I

BIOFILTRATION I
\
TW2A
•
' '
Q.M,A, L£G£ND
D£SCRIPTION

PROPERTY LINE/PROJECT BOUNDARY
SYMBOL

PROPOSED CURB AND GUTTER
EX/51/NG CONTOUR .....________630 ~

PROPOSED DMA LIMITS
------

DIRECTION OF DRAINAGE
STORM DRAIN PIP£ SIZE PER PLAN
TR££ WELL
_.,, __ __, ____ ., __
C
NOD£ NUMBER £1\
Q100 (C.F.5.) ~
£LEV.

BASIN /D£NTIR£R ------------1, 11!£c=::-;:5;l
BASIN AREA (AC.) __________ __j:,::1i"_90,5sro"10I
UNDERLYING HYDROLOGJC SOILS GROUP: TYPE •o•
APPROX/MA TE D£P111 TO GROUND WA T£R: GR£A TER 111AN 20 F££T EX/51/NG NA 1URAL HYDROLOG/C F£A 1UR£S: N/A
POTENTIAL CRITICAL COARSE SEDIMENT YIELD AREAS: N/A
EXISTING TOPOGRAPHY: SHOWN
EX/51/NG IMPERVIOUS AREAS: SHOWN
EX/51/NG DRAINAGE SYSTEM:

PROPOSED DRAINAGE: SYSTEM:

PROPOSED DEMOLITION:

PROPOSED GRADING:

PROPOSED IMPERVIOUS SURFACES:

DMA AREAS:

SHOWN
SHOWN
N/A
SHOWN

PAVING AND BUILDINGS
5££ TABLE
POLLUTANT SOURCES:
5TRUC1URAL SOURCE CONTROL:

PA VE'M£NT AND LANDSCAPE AREAS
SHOWN
INLET 5/GNAGE:

TRASH ENCLOSURE CONTROLS:

TR£A TM£NT BMP:

SQURC£ CONTROL BMPS
STORM DRAIN INLETS.

LANDSCAPE/OUTDOOR PESTICIDE USE.

FIR£ SPRINKLER TEST WA T£R.

MISCELLANEOUS DRAIN OR WASH WA T£R.

PLAZAS, SIDEWALKS, ANO PARKING LOTS.

MINIMIZE IMPERVIOUS AREA.

BACK OF
EX. SIDEWALK
R/W

REPLA CED

SIDEWALK

ROOT CONTROL

BARRIER PER
SDRSD L- 06
N/A

PROVIDED
5££ TABLE
SIT£ D£SIGN BMPS
0 0
1!21
30 Mil

PLAST IC
LINER
RUNOFF COLL[CT/ON.

LANDSCAPE WITH NATIVE OR
DRAUGHT TOLERANT SPECIES.

INDOOR/STRUCTURAL PEST CONTROL.

ADHERE LINER
TO Ut.AITS OF

REPLACED
SIDEWALK SECTION a-a

LIMITS OF ROOTING SOIL

PER DESIGN PLANS

REPLACE SIDEWALK AS

NECESSARY FOR EXPANDE
STRUCnJRAL SOIL VOLUME
A
L

EP ROOT

TREE BUBBLER
(/4,1/Cb~ER ~04
OOT CON Ol

BARR IER PER
SDRSD l-06
A
J

CURB & GUTTER
PER SDRSD G- 02
18" WIDE CURB
CUT PER GS- 5.01

SPLASH PAO
PER GS-5 .06
30 MIL

PLASTIC
LINER
lf4x8" SIAOOTI-I
DOWELS @ 18" O.C.

GREASED ON ONE ENO,
TYP. All SIDES EXISTING

SIDEWALK

PLAN VIEW

EXPANSION JOHH,
TYP. ALL SIDES
INSTALL JO Mil PLASTIC

LINER WHERE CONCRETE IS
POUR£0 OVER STRUCTURAL
SOIL {TYP.)

REPLA CE SIDEWALK

AS NECESSARY
FOR EXP.ANDED
y

OOT CON TRO
BARRIER PE~
SDRSD L-06
l -e='fi==aROO'=T=,==;jh c"z
X ,0
; /14 @ 18" O.C.
. , BOTH WAYS
y
.. ROOT CONTROL

BARR IER PER

EXISTING

SIDEWALK

STRUCTURAL SOIL
VOLUME
NOTES;
3D MIL

PLASTIC
LINER
"
BALL ~

STRUCTURAL
SOIL l'
~ X SDRSO L-06

SECTION A-A
'x_:< I x

SAND FILTER
LAYER
30 MI L

PLAST K
LINER

1. REF'ER TO GS-1.00 FOR t<.LL DETAILS NOT SHOW'N HERE.

2. TREE SIZE & TYPE PER DESIGl'I PL.A.NS. DRAWING NOT TO SCALE RE\IISIOOS Af'F'ROl'[D llA lE DRA\11!1 B'r':.Alli!... CH(l);.("0 BY· J!.E.. SAN DIEGO COUNTY DESIGN STANDARD ORIGINAL iO- D1 - 2019 RECO~~EHl.'t]). BY: CHAR.ES MOHRLOCK, P.[ J\PPROVEO Bt CCllHTY ENGINEER
t,J (' 'r"0.<11Jl7";ZllAlE: ,.,,,._/n
l\ll.l.J.\WP. Ml'l'I ,PL
~.U . NI), ~~52. {~ 9 31;/2020

JO IMIL

PLASTIC LI ER
8" MIN +--,,,.;''--t-f~
PER FORA TED _,.

SCH 40 PVC PIPE
(PER GEOTECH.

SEE GS-1.05)
ClEANOUT
PER GS-5.9
#4x8" SMOOTH
DOWELS @ 18" O.C,
GREASED ON ONE END.

TYP _ ALL SIDES
18" 'MDE

CURB CUT
PER GS-5,01

COMPACTED

AGGREGATE

BASE FOR

ROADWAY
30 Mil

PL ASTIC LINER

ROOT CONTROL

BARRIER PER
SDRSD L- 06
I ,--
8" MIN PERFORATED
SCH 40 PVC PIPE
(PER GEOTECH, SEE GS-1.05)
DESIGN NOTES:

LARGE TREE

WELL DR AWIN G
NU MBER GS-1.02
4' TYP.

PLAN
5' - 0"
3'-6"
SPLA SH PAD - ~
PER GS-5 .06 O:'. ~ 2
LL.I <( '
'
t
ROOT
BALL
C

0. 5:_ ~

SECTION A-A
5' MIN.

SIDEWALi<

ROOT CONTROL

BARR IER PER
SORSD L- 06
LINER PENETRATION •
PER DESICN PLANS, g:

SIMILAR TO DETAIL A ,
ON GS- 5.12 "i.D

IRRIGATION

DESIGN PER
PLANS

DEEP ROOT

TREE BUBBLER
PER SORSD 1- 04
3" SHREDDED

HARD'MJOD
MULCH
l

EXPANSION JOINT
PER l-03, T"r'P.
#4 @ 1E:- o_c.

BOTH WAYS
"' m O
l:!:!Lt'.I
~
< 0 ,~
95% COMPACTION I")

UNDER CONCRETE
FRAME, TYP.

STRUCTURAL SOIL
Dl::PTH PER DESIGN
PLANS. 30 " MIN.
6" SANO FILTER LA YER
(PER GEOTECH, SEE GS- 1.05)

1. STREET IMPROVEMENTS ANO DRAINAGE STRUCTURES SHALL BE CONSTRUCTED ACCORDING TO THE LATEST SAN DIEGO REGIONAL STANDARD DRAWINGS AND CALTRANS STANDARD PLANS_ 2- CONCRETE $H ALL BE 520-C-2500 UNLESS 0TH£R WISE SPECIFIED. 3_ SEE SORSD owe L-01 THROUGH l -06 FOR DETAILS NOT SPECIFIED HEREIN,

4. MINIMUM OPEN TREE PLANTING SPACE CllMENSION 4'x6'.

5. PROVIDE 30 MIL PLAST IC LINER \¼-iERE CONCRETE 'WILL BE POURED ON TOP OF STRUCTURA L SOil.

6. SEAL PLA STrC LINE:R TO ADJACENT IMPROVEMENTS AND EDGE F?ESTRAINTS PER GS-5,1$,

7. Wf-l[N $AND FILTER LAYER 1$ OMITTED, PRO"\J1DE GEOTE"XTILE BENEATH THE STRUCTURAL SOIL LAYER P£R PROJECT - SPEClflC GEOTECHNICAL RECOMMENDATIONS.

8. PROPOSED SIDEWALK LOCATIONS & INTENDED AOA ROUTES PER PROJECT - SPECIFIC DESIGN PLANS. 9_ FOR TREE WELL SU8SURF ACE DRAINAGE TYPES, SEE DWG GS- 1.05.

DRAWING NOT TO SCALE
oR~~ B'l:.!IOO... am:uo B'f . ....Rt.
~COU~[~[)[O BY: DIARLES 11:JHRLOO(, P.E.

APPRl'.l\ID BY OOJNIY ENG1t£ER
0 (I Yv\,11J(=;;IllAIE: ' "' /•~/•"'
l\llli\ ~ P. Ua:! ~.E.
~.C.£. NO, 494-$2. ('/P 9 J0/2(120

SAN DIEGO COUNTY DESIGN STANDARD

TREE WELL

GENERAL DESIGN GUIDANCE
RE\1~S APl'R0\1-:D DATE
ORIGINAL 10- 01- 2079

OR AWING
NUMBER GS-1.00
•
u z - ~
PLANNING ENGINEERING SURVEYING /S_

GRAPHIC SCALE
--- -
399:J Ruffin Road, Suite 1 :20
San Diego, Ca. 9g123
B5B-560-1141 --- -40 D 40 BO 120 85&560-81 57 Fax
i;
i
'---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------' ~
6-30-20 75050.65
Barham Drive Updated 20-Jun-2020

0.90 Impervious Coefficient

0.30 Pervious Coefficent Soil Type D

0.62 85th Percentile

DMA TOTAL AREA IMPERVIOUS IMPERVIOUS PERVIOUS

ADJUSTED

AREA DCV

SURFACE AREA
REQUIRED *

SURFACE AREA

PROVIDED BMP TYPE / STANDARD BMP
NO (SF) (SF) (%) (SF) (SF) (CF) (SF) (SF) ID
P-1 2,993 2,394 80% 599 2,334 121 70 BIOFILTRATION BF-2 / NUTRIENT SENSITIVE MEDIA BMP1 P-2 104,304 83,444 80% 20,861 81,357 4,203 2,441 BIOFILTRATION BF-2 / NUTRIENT SENSITIVE MEDIA BMP1 P-3 28,188 22,550 80% 5,638 21,986 1,136 660 BIOFILTRATION BF-2 / NUTRIENT SENSITIVE MEDIA BMP1 P-4 24,350 19,480 80% 4,870 18,993 981 570 BIOFILTRATION BF-2 / NUTRIENT SENSITIVE MEDIA BMP1 P-5 147,716 118,173 80% 29,543 115,219 5,953 3,457 BIOFILTRATION BF-2 / NUTRIENT SENSITIVE MEDIA BMP1 C 19,863 - 0% 19,863 7,197 7,330 BIOFILTRATION BF-2 / NUTRIENT SENSITIVE MEDIA BMP1 A1 2,433 2,190 90% 243 2,044 106 61 20' DIA TW1 TREE WELL A1A 2,433 2,190 90% 243 2,044 106 61 20' DIA TW1 A TREE WELL A2 2,683 2,683 100% - 2,415 125 72 WEST DRIVEWAY DE MINIMIS A3 2,217 1,774 80% 443 1,729 89 52 20' DIA TW2 TREE WELL A3A 2,217 1,774 80% 443 1,729 89 52 20' DIA TW2 A TREE WELL A4 11,478 6,657 58% 4,821 7,438 384 223 30' DIA TW3 TREE WELL A5 1,289 1,289 100% - 1,160 60 35 EAST DRIVEWAY DE MINIMIS A 20,388 1,019 5% 19,368 6,728 348 202 BARHAM SLOPE SELF-TREATING SITE 372,553 265,617 71% 106,936 265,177 13,701 E-1 109,244 - 0% 109,244 - BYPASS DITCH & STORM DRAIN SELF-TREATING E-2 72,898 - 0% 72,898 - BYPASS DITCH & STORM DRAIN SELF-TREATING E-3 10,424 - 0% 10,424 - BYPASS DITCH & STORM DRAIN SELF-TREATING E-4 20,221 - 0% 20,221 - BYPASS DITCH & STORM DRAIN SELF-TREATING E-5 11,265 - 0% 11,265 - BYPASS DITCH & STORM DRAIN SELF-TREATING E-6 6,212 - 0% 6,212 - BYPASS DITCH & STORM DRAIN SELF-TREATING E-7 8,285 - 0% 8,285 - BYPASS DITCH & STORM DRAIN SELF-TREATING B 31,354 28,219 90% 3,135 - EXISTING BARHAM PAVING SELF-TREATING TOTALS 642,455 293,836 45.7% 348,619

14.75 6.75 8.00

DMA & BMP SUMMARY TABLE
D:\75051 Barham Drive\13 Reports\In-house Prelim Reports\ProjectData DMA B1..L3 San Diego County
85 th Percentile lsopluvials
Legend
--85th PERCENTILE ISOPLUVIAL
[°_-_~:.J INCORPORATED CITY
NOTE:

The 85th percent ile is a 24 hour rainfall total.

It represetns a value such that 85% of the
observed 24 hour rainfall totals will be less
than that value .

N
+
~ Mill's
0 1 2 4 8 8
THIS IAAP,O,,..T,.1$ l'ftOVIOEtl VIITHOUT !MRRANTY Of'N4Y KIHO, t'1™ER EXPRESSOAIMPUEO, INO..UONO lllJl J<tOTUMITEOlO. THE IMPLED ~IESOF MERCHANlA81UfY ANOFllNESS FORA PIUITICUlAA
PURP05E NaleTio9produc:l~-~ .... ,_ ... SANCl,\c;
Rt,g.an .. ~~--be~""'""""U.wrlll!n ~Of&\Nll,lr,GTr.p,Odua....,conratnl'IIOr,,_~ ~~l>l'~Mcfqlly l ~,,._.tl.S.,01$ Tr,,.ra_,,.
t:QP7fV'llt<lin'R""'3~ & 0;,mpe~••~IOOOPrOI~
.. or"r""11"""'°'...,,.,.,.'°'_ ...... or,ftllle ~"'""°' w,;q., ~olRardM<tlally l Cotllf'lln,9
~&nGIS101•·MRlgl'II- FIIIIIHIOl_fa(j,11_.»Cloll a.
-•-11111-Nng,a~---
D~'U/201~
PFIIXld~_ATI.AS_1,'PCTll5_REVISITED_l01!P.

PClM_OISPI.AflUII
Figure B.1-1: 85th Percentile 2
Category # Description Value Units
0 Design Capture Volume for Entire Project Site 13,190 cubic-feet 1 Proposed Development Type Residential unitless
2 Number of Residents or Employees at Proposed Development 453 # 3 Total Planted Area within Development 67,704 sq-ft
4 Water Use Category for Proposed Planted Areas Low unitless 5 Is Average Site Design Infiltration Rate ≤0.500 Inches per Hour? No yes/no 6 Is Average Site Design Infiltration Rate ≤0.010 Inches per Hour? No yes/no 7 Is Infiltration of the Full DCV Anticipated to Produce Negative Impacts? Yes yes/no 8 Is Infiltration of Any Volume Anticipated to Produce Negative Impacts? Yes yes/no 9 36-Hour Toilet Use Per Resident or Employee 1.86 cubic-feet 10 Subtotal: Anticipated 36 Hour Toilet Use 845 cubic-feet 11 Anticipated 1 Acre Landscape Use Over 36 Hours 52.14 cubic-feet 12 Subtotal: Anticipated Landscape Use Over 36 Hours 81 cubic-feet 13 Total Anticipated Use Over 36 Hours 926 cubic-feet
14 Total Anticipated Use / Design Capture Volume 0.07 cubic-feet 15 Are Full Capture and Use Techniques Feasible for this Project? No unitless 16 Is Full Retention Feasible for this Project? No yes/no 17 Is Partial Retention Feasible for this Project? No yes/no Result 18 Feasibility Category 5 1, 2, 3, 4, 5
Worksheet B.3-1 General Notes:

H. PDPs participating in an offsite alternative compliance program are not held to the feasibility categories presented herein.

Capture & Use
Inputs
Automated Worksheet B.3-1: Project-Scale BMP Feasibility Analysis (V1.3) C. Feasibility Category 1: Applicant must implement capture & use, retention, and/or infiltration elements for the entire DCV.

D. Feasibility Category 2: Applicant must implement capture & use elements for the entire DCV.

E. Feasibility Category 3: Applicant must implement retention and/or infiltration elements for all DMAs with Design Infiltration Rates greater than 0.50 in/hr.

B. Negative impacts associated with retention may include geotechnical, groundwater, water balance, or other issues identified by a geotechnical engineer and substantiated through completion of Form I-8.

Infiltration
Inputs
G. Feasibility Category 5: Applicant must implement standard lined biofiltration BMPs sized at ≥3% of the effective impervious tributary area for all DMAs with Design Infiltration Rates of 0.010 in/hr or less. Applicants may also be permitted to implement reduced size and/or specialized biofiltration BMPs provided additional criteria identified in "Supplemental Retention Criteria for Non-Standard Biofiltration BMPs" are satisfied.

A. Applicants may use this worksheet to determine the types of structural BMPs that are acceptable for implementation at their project site (as required in Section 5 of the BMPDM). User input should be provided for yellow shaded cells, values for all other cells will be automatically generated. Projects demonstrating feasibility or potential feasibility via this worksheet are encouraged to incorporate capture and use features in their project.

F. Feasibility Category 4: Applicant must implement standard unlined biofiltration BMPs sized at ≥3% of the effective impervious tributary area for all DMAs with Design Infiltration Rates of 0.011 to 0.50 in/hr. Applicants may be permitted to implement lined BMPs, reduced size BMPs, and/or specialized biofiltration BMPs provided additional criteria identified in "Supplemental Retention Criteria for Non-Standard Biofiltration BMPs" are satisfied.

Calculations

GEOTECHNICAL INVESTIGATION
943 BARHAM DRIVE

SAN MARCOS, CALIFORNIA

PREPARED FOR

HALLMARK COMMUNITIES

SOLANA BEACH, CALIFORNIA
JUNE 17, 2020
PROJECT NO. G2516-32-01
Worksheet C.4-1: Categorization of Infiltration Feasibility Condition Part 1 - Full Infiltration Feasibility Screening Criteria Would infiltration of the full design volume be feasible from a physical perspective without any undesirable consequences that cannot be reasonably mitigated? Criteria
1 Screening Question
Is the estimated reliable infiltration rate below proposed facility locations greater than 0.5 inches per hour? The response to this Screening Question shall be based on a comprehensive evaluation of the factors presented in
Appendix C.2 and Appendix D.

Yes No
X
Provide basis: We performed one infiltration test using our Aardvark constant head permeameter. The results indicate a design infiltration rate of 0.01 inches per hour (with an applied factor of safety of 2). Full infiltration is considered infeasible if the design rate is below 0.5 iph. Therefore, full infiltration is not considered feasible at the site.
2 Can infiltration greater than 0.5 inches per hour be allowed without increasing risk of geotechnical hazards (slope
stability, groundwater mounding, utilities, or other factors) that cannot be mitigated to an acceptable level? The
response to this Screening Question shall be based on a comprehensive evaluation of the factors presented in
Appendix C.2.

X
Provide basis: Infiltration at the proposed location may result in lateral water migration that could adversely impact adjacent utilities, roadways, and foundations. The adverse impacts of infiltration could be reasonably mitigated to accepted levels provided side liners and a subdrain are incorporated into the design. In addition, an overflow device should be added to prevent overtopping of the BMP slopes.

Criteria
3 -, _.. - ••I~ I ' ,..__. ...

Screening Question
Can infiltration greater than 0.5 inches per hour be allowed without increa sing risk of groundwater contamination
(shallow water table, storm water pollutants or other factors) that cannot be mitigated to an acceptable level? The
response to this Screening Question shall be based on a comprehensive evaluation of the factors presented in
Appendix C.3.

Yes No
X
Provide basis: Groundwater is not located within 10 feet of the proposed BMP basin. The risk of storm water infiltration adversely impacting groundwater is considered negligible.

Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc.

Provide narrative discussion of study/data source applicability . 4 Can infiltr ation greater than 0.5 inche s per hour be allowed without cau sing potenti al water balance issues such as change of se asonality of ephemer al streams or inc reased discharg e of cont amin ated groundw ater to surface waters? The response to this Screening Question shall be based on a comprehensive evaluation of the factors presented in
Appendix C.3.

X
Provide basis: We are not aware of any potentia l water balance issues or change of ephe meral stream flow as a result of infiltrating storm water. Researching downstream water rights and evaluating water balance issues to stream flows is beyond the scope of the geotechnica l engineer.

Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc.

Provide narrative discussion of study/data source applicability .

Part 1
Result*
If all answers to rows 1- 4 are "Yes" a full infiltration design is potentially feasible . The feasibility screening category is Full Infiltr ation If any answer from row 1-4 is "No", infiltration may be possible to some extent but would not generally be feasible or desirable to achieve a "full infiltration " design. Proceed to Part 2
NO
*To be compl eted using gath ered site information and best prof essional judgm ent considering th e definiti on of MEP in the MS4 Permit. Additional testing and/or studies may be requir ed by City Engineer to substanti ate finding s. - •. ' - 7afl_~ I ' ....... ____
Part 2 - Partial Infiltration vs. No Infiltration Feasibility Screening Criteria Would infiltration of water in any appreciable amount be physically feasible without any negative consequences that cannot be reasonably mitigated?
Criteria
5 Screening Question
Do soil and geologic conditions allow for infiltration in any appreciable rate or volume? The response to this Screening Question shall be based on a comprehensive evaluation of the factors presented in Appendix C.2 and Appendix D.

Yes No
X
Provide basis: An appreciable rate is typically defined as a factore d rate of at least 0.05 inches per hour (using a factor of safety of 2). Based on our experience and field testing, we anticipate that the saturated hydra ulic conducti vity (Ksat) of the compacted fill will be less than 0.05 inch es per hour. T he in-situ infiltratio n test results on the und erlying alluvium indi cated a design rate of 0.01 iph. The colluvium and granitic rock are expected to be less permeable than the alluvium teste d. T herefo re, in our opinion the soil and geologic conditi ons do not allow for infiltration in any appreciable rate or volume based on infiltra tion rates.

Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc.

Provide narrative discussion of study/data source applicability and why it was not feasible to mitigate low infiltration rates .
6 Can Infiltration in any appreciable quantity be allowed without increasing risk of geotechnical hazards (slope
stability, groundwater mounding, utilities, or other factors) that cannot be mitigated to an acceptable level? The
response to this Screening Question shall be based on a comprehensive evaluation of the factors presented in
Appendix C.2.

X
Provide basis: Infil tration at the propose d location may result in lateral water migration that could adversely imp act adjacent utilities, roa dways, and foundations . The adverse impacts of infiltratio n could be reasona bly mitigated to accepted levels provided side liners and a subdr ain are incorp orated into the design. In additi on, an over flow device sho uld be added to prevent overtop ping of the BMP slopes .

Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc.

Provide narrative discussion of study/data source applicability and why it was not feasible to mitigate low infiltration rates.

Criteria
7 Screening Question
Can Infiltration in any appreciable quantity be allowed without posing signific ant risk for groundwater related concerns (shallow water table, storm water pollutants or other factor s)? The response to this Screening Question shall be based on a comprehensive evaluation of the factors
presented in Appendix C.3.

Yes No
X
Provide basis: Gro undwater is not locate d within 10 feet of the pro pose d BMP basin. The risk of storm water infilt ration advers ely imp acting gro undwater is cons idered negligible.

Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc.

Provide narrative discussion of study/data source applicability and why it was not feasible to mitigate low infiltration rates.
8 Can infiltration be allowed without violating downstream water rights? The response to this Screening Question shall be based on a comprehensive evaluation of the factors
presented in Appendix C.3.

X
Provide basis: We are not aware of any downstream wate r rights. Researching downstream wate r rights is beyond the scope of the geote chni cal engineer.

Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc .

Provide narrative discussion of study/data source applicability and why it was not feasible to mitigate low infiltration rates.

Part 2
If all answers from row 5-8 are yes then partial infiltration design is potentially feasible. The feasibility screening category is Partial Infiltration.

No
Result* If any answer from row 5-8 is no, then infiltration of any volume is considered Infiltration to be infea sible within the drainage area. The feasibility screening category is No Infiltration .
*To be completed using gathered site information and best professional judgment considering the definition of MEP in the MS4 Permit . Additional testing and/or studies may be required by Agency/Jurisdictions to substantiate findings.

Category # Description i ii iii iv v vi vii viii ix x Units 0 Drainage Basin ID or Name BMP1 TW1 TW1 A TW2 TW2 A TW3 unitless 1 Basin Drains to the Following BMP Type Biofiltration n/a n/a n/a n/a n/a unitless 2 85th Percentile 24-hr Storm Depth 0.62 0.62 0.62 0.62 0.62 0.62 0.62 0.62 0.62 0.62 inches 3 Design Infiltration Rate Recommended by Geotechnical Engineer 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 in/hr 4 Impervious Surfaces Not Directed to Dispersion Area
(C=0.90) 246,041 2,190 2,190 1,774 2,217 6,657 sq-ft
5 Semi-Pervious Surfaces Not Serving as Dispersion Area (C=0.30) 0 0 sq-ft 6 Engineered Pervious Surfaces Not Serving as Dispersion Area (C=0.10) 0 0 sq-ft 7 Natural Type A Soil Not Serving as Dispersion Area (C=0.10) 0 0 sq-ft 8 Natural Type B Soil Not Serving as Dispersion Area (C=0.14) 0 0 sq-ft 9 Natural Type C Soil Not Serving as Dispersion Area (C=0.23) 0 0 sq-ft 10 Natural Type D Soil Not Serving as Dispersion Area (C=0.30) 61,510 243 243 443 443 4,821 sq-ft 11 Does Tributary Incorporate Dispersion, Tree Wells, and/or Rain Barrels? No Yes Yes Yes Yes Yes No No No No yes/no 12 Impervious Surfaces Directed to Dispersion Area per SD-B (Ci=0.90) sq-ft 13 Semi-Pervious Surfaces Serving as Dispersion Area per SD-B (Ci=0.30) sq-ft 14 Engineered Pervious Surfaces Serving as Dispersion Area per SD-B (Ci=0.10) sq-ft 15 Natural Type A Soil Serving as Dispersion Area per SD-B (Ci=0.10) sq-ft 16 Natural Type B Soil Serving as Dispersion Area per SD-B (Ci=0.14) sq-ft 17 Natural Type C Soil Serving as Dispersion Area per SD-B (Ci=0.23) sq-ft 18 Natural Type D Soil Serving as Dispersion Area per SD-B (Ci=0.30) sq-ft 19 Number of Tree Wells Proposed per SD-A 1 1 1 1 1 #
20 Average Mature Tree Canopy Diameter 20 20 20 20 30 ft 21 Number of Rain Barrels Proposed per SD-E #
22 Average Rain Barrel Size gal
23 Does BMP Overflow to Stormwater Features in Downstream Drainage? No No No No No No No No No No unitless
24 Identify Downstream Drainage Basin Providing Treatment in Series unitless 25 Percent of Upstream Flows Directed to Downstream Dispersion Areas percent 26 Upstream Impervious Surfaces Directed to Dispersion Area (Ci=0.90) 0 0 0 0 0 0 0 0 0 0 cubic-feet 27 Upstream Impervious Surfaces Not Directed to Dispersion Area (C=0.90) 0 0 0 0 0 0 0 0 0 0 cubic-feet 28 Total Tributary Area 307,551 2,433 2,433 2,217 2,661 11,478 0 0 0 0 sq-ft 29 Initial Runoff Factor for Standard Drainage Areas 0.78 0.84 0.84 0.78 0.80 0.65 0.00 0.00 0.00 0.00 unitless 30 Initial Runoff Factor for Dispersed & Dispersion Areas 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 unitless 31 Initial Weighted Runoff Factor 0.78 0.84 0.84 0.78 0.80 0.65 0.00 0.00 0.00 0.00 unitless 32 Initial Design Capture Volume 12,394 106 106 89 110 385 0 0 0 0 cubic-feet 33 Total Impervious Area Dispersed to Pervious Surface 0 0 0 0 0 0 0 0 0 0 sq-ft 34 Total Pervious Dispersion Area 0 0 0 0 0 0 0 0 0 0 sq-ft 35 Ratio of Dispersed Impervious Area to Pervious Dispersion Area n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a ratio 36 Adjustment Factor for Dispersed & Dispersion Areas 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 ratio 37 Runoff Factor After Dispersion Techniques 0.78 0.84 0.84 0.78 0.80 0.65 n/a n/a n/a n/a unitless 38 Design Capture Volume After Dispersion Techniques 12,394 106 106 89 110 385 0 0 0 0 cubic-feet 39 Total Tree Well Volume Reduction 0 180 180 180 180 420 0 0 0 0 cubic-feet 40 Total Rain Barrel Volume Reduction 0 0 0 0 0 0 0 0 0 0 cubic-feet 41 Final Adjusted Runoff Factor 0.78 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 unitless 42 Final Effective Tributary Area 239,890 0 0 0 0 0 0 0 0 0 sq-ft 43 Initial Design Capture Volume Retained by Site Design Elements 0 180 180 180 180 420 0 0 0 0 cubic-feet 44 Final Design Capture Volume Tributary to BMP 12,394 0 0 0 0 0 0 0 0 0 cubic-feet Worksheet B.1-1 General Notes:

False
False
False
Automated Worksheet B.1-1: Calculation of Design Capture Volume (V1.3) A. Applicants may use this worksheet to calculate design capture volumes for up to 10 drainage areas User input must be provided for yellow shaded cells, values for all other cells will be automatically generated, errors/notifications will be highlighted in red and summarized below.

Upon completion of this worksheet, proceed to the appropriate BMP Sizing worksheet(s).

Dispersion
Area, Tree Well
& Rain Barrel
Inputs
(Optional)
Standard
Drainage Basin
Inputs
Results
Tree & Barrel
Adjustments
Initial Runoff
Factor
Calculation
Dispersion
Area
Adjustments
Treatment
Train Inputs &
Calculations
False
Category # Description i ii iii iv v Units
0 Drainage Basin ID or Name BMP1 - - - - sq-ft
1 Design Infiltration Rate Recommended by Geotechnical Engineer 0.000 - - - - in/hr 2 Effective Tributary Area 239,890 - - - - sq-ft
3 Minimum Biofiltration Footprint Sizing Factor 0.030 - - - - ratio 4 Design Capture Volume Tributary to BMP 12,394 - - - - cubic-feet 5 Is Biofiltration Basin Impermeably Lined or Unlined? Lined unitless 6 Provided Biofiltration BMP Surface Area 7,330 sq-ft
7 Provided Surface Ponding Depth 12 inches
8 Provided Soil Media Thickness 18 inches
9 Provided Depth of Gravel Above Underdrain Invert 9 inches 10 Diameter of Underdrain or Hydromod Orifice (Select Smallest) 2.00 inches 11 Provided Depth of Gravel Below the Underdrain 3 inches 12 Volume Infiltrated Over 6 Hour Storm 0 0 0 0 0 cubic-feet 13 Soil Media Pore Space Available for Retention 0.05 0.05 0.05 0.05 0.05 unitless 14 Gravel Pore Space Available for Retention 0.00 0.00 0.00 0.00 0.00 unitless 15 Effective Retention Depth 0.90 0.00 0.00 0.00 0.00 inches 16 Calculated Retention Storage Drawdown (Including 6 Hr Storm) 120 0 0 0 0 hours 17 Volume Retained by BMP 550 0 0 0 0 cubic-feet
18 Fraction of DCV Retained 0.04 0.00 0.00 0.00 0.00 ratio 19 Portion of Retention Performance Standard Satisfied 0.05 0.00 0.00 0.00 0.00 ratio 20 Fraction of DCV Retained (normalized to 36-hr drawdown) 0.02 0.00 0.00 0.00 0.00 ratio 21 Design Capture Volume Remaining for Biofiltration 12,146 0 0 0 0 cubic-feet 22 Max Hydromod Flow Rate through Underdrain 0.1869 n/a n/a n/a n/a CFS 23 Max Soil Filtration Rate Allowed by Underdrain Orifice 1.10 n/a n/a n/a n/a in/hr 24 Soil Media Filtration Rate per Specifications 5.00 5.00 5.00 5.00 5.00 in/hr 25 Soil Media Filtration Rate to be used for Sizing 1.10 5.00 5.00 5.00 5.00 in/hr 26 Depth Biofiltered Over 6 Hour Storm 6.61 30.00 30.00 30.00 30.00 inches 27 Soil Media Pore Space Available for Biofiltration 0.20 0.20 0.20 0.20 0.20 unitless 28 Effective Depth of Biofiltration Storage 19.20 0.00 0.00 0.00 0.00 inches 29 Drawdown Time for Surface Ponding 11 0 0 0 0 hours
30 Drawdown Time for Effective Biofiltration Depth 17 0 0 0 0 hours 31 Total Depth Biofiltered 25.81 30.00 30.00 30.00 30.00 inches 32 Option 1 - Biofilter 1.50 DCV: Target Volume 18,219 0 0 0 0 cubic-feet 33 Option 1 - Provided Biofiltration Volume 15,766 0 0 0 0 cubic-feet 34 Option 2 - Store 0.75 DCV: Target Volume 9,110 0 0 0 0 cubic-feet 35 Option 2 - Provided Storage Volume 9,110 0 0 0 0 cubic-feet 36 Portion of Biofiltration Performance Standard Satisfied 1.00 0.00 0.00 0.00 0.00 ratio 37 Do Site Design Elements and BMPs Satisfy Annual Retention Requirements? Yes - - - - yes/no 38 Overall Portion of Performance Standard Satisfied 1.00 0.00 0.00 0.00 0.00 ratio 39 This BMP Overflows to the Following Drainage Basin - - - - - unitless 40 Deficit of Effectively Treated Stormwater
0 n/a n/a n/a n/a cubic-feet
Worksheet B.5-1 General Notes:

False
Retention
Calculations
Automated Worksheet B.5-1: Sizing Lined or Unlined Biofiltration BMPs (V1.3) False
BMP Inputs
False
Biofiltration
Calculations
A. Applicants may use this worksheet to size Lined or Unlined Biofiltration BMPs (BF-1, PR-1) for up to 10 basins. User input must be provided for yellow shaded cells, values for blue cells are automatically populated based on user inputs from previous worksheets, values for all other cells will be automatically generated, errors/notifications will be highlighted in red/orange and summarized below. BMPs fully satisfying the pollutant control performance standards will have a deficit treated volume of zero and be highlighted in green.

False
False
False
False
Result
False
False
Category # i ii iii iv v vi vii viii ix x Units
0 BMP1 - - - - - - - - - unitless
1 Biofiltration - - - - - - - - - unitless
2 239,890 - - - - - - - - - sq-ft
3 No No No No No No No No yes/no
4 inches
5 lb/sq-ft
6 years
7 yes/no
8 Commercial: TSS=128 mg/L, C= 0.80 sq-ft
9 Education: TSS=132 mg/L, C= 0.50 sq-ft
10 Industrial: TSS=125 mg/L, C= 0.90 sq-ft
11 Low Traffic Areas: TSS=50 mg/L, C= 0.50 sq-ft
12 Multi-Family Residential: TSS=40 mg/L, C= 0.60 sq-ft 13 Roof Areas: TSS=14 mg/L, C= 0.90 sq-ft
14 Single Family Residential: TSS=123 mg/L, C= 0.40 sq-ft 15 Transportation: TSS=78 mg/L, C= 0.90 sq-ft
16 Vacant/Open Space: TSS=216 mg/L, C= 0.10 sq-ft
17 0 0 0 0 0 0 0 0 0 0 sq-ft
18 0 0 0 0 0 0 0 0 0 0 mg/L
19 0 0 0 0 0 0 0 0 0 0 cubic-feet
20 0 0 0 0 0 0 0 0 0 0 lb/yr
21 0 0 0 0 0 0 0 0 0 0 lb/yr
22 0.030 - - - - - - - - - ratio
Worksheet B.5-3 General Notes:

False
Automated Worksheet B.5-3: Alternate Minimum Biofiltration Footprint Ratio (V1.3) Description
Drainage Basin ID or Name
Average Annual Precipitation
Is Proposed Biofiltration BMP <3% of Effective Tributary Area Desired? Drainage Basin
Info Drains to following BMP Type
A. Applicants may use this worksheet to calculate Alternate Minimum Biofiltration Footprint Ratios for up to 10 basins. User input must be provided for yellow shaded cells, values for blue cells are automatically populated based on user inputs from previous worksheets, values for all other cells will be automatically generated, errors/notifications will be highlighted in red and summarized below. Inputs for Lines 4-7 (precipitation, load to clog, clogging period, and pretreatment measures) must be supported through supplemental documentation.

False
Final Effective Tributary Area
Load to Clog (default =2.0)
Average Annual TSS Load After Pretreatment Measures
Average Annual Runoff
Average Annual TSS Load
Minimum Allowable Biofiltration Footprint Ratio
Average TSS Concentration for Tributary
Allowable Period to Accumulate Clogging Load (default =10) Pretreatment Measures Included?
Effective-Area Based on Specified Land Use Coefficients Minimum
Footprint
Calculations
Biofiltration
Clogging
Inputs
Category # Description i ii iii iv v vi Units
0 Drainage Basin ID or Name BMP1 TW1 TW1 A TW2 TW2 A TW3 unitless 1 85th Percentile Storm Depth 0.62 0.62 0.62 0.62 0.62 0.62 inches 2 Design Infiltration Rate Recommended by Geotechnical
Engineer 0.000 0.000 0.000 0.000 0.000 0.000 in/hr
3 Total Tributary Area 307,551 2,433 2,433 2,217 2,661 11,478 sq-ft 4 85th Percentile Storm Volume (Rainfall Volume) 15,890 126 126 115 137 593 cubic-feet 5 Initial Weighted Runoff Factor 0.78 0.84 0.84 0.78 0.80 0.65 unitless 6 Initial Design Capture Volume 12,394 106 106 89 110 385 cubic-feet 7 Dispersion Area Reductions 0 0 0 0 0 0 cubic-feet
8 Tree Well and Rain Barrel Reductions 0 180 180 180 180 420 cubic-feet 9 Effective Area Tributary to BMP 239,890 0 0 0 0 0 square feet 10 Final Design Capture Volume Tributary to BMP 12,394 0 0 0 0 0 cubic-feet 11 Basin Drains to the Following BMP Type Biofiltration n/a n/a n/a n/a n/a unitless 12 Volume Retained by BMP
(normalized to 36 hour drawdown) 248 0 0 0 0 0 cubic-feet 13 Total Fraction of Initial DCV Retained within DMA 0.02 1.70 1.70 2.02 1.64 1.09 fraction 14 Percent of Average Annual Runoff Retention Provided 3.0% 93.6% 93.6% 96.7% 93.0% 82.8% % 15 Percent of Average Annual Runoff Retention Required 1.5% 1.5% 1.5% 1.5% 1.5% 1.5% % Performance
Standard 16 Percent of Pollution Control Standard Satisfied 100.0% 100.0% 100.0% 100.0% 100.0% 100.0% % 17 Discharges to Secondary Treatment in Drainage Basin - - - - - - unitless 18 Impervious Surface Area Still Requiring Treatment 0 0 0 0 0 0 square feet 19 Impervious Surfaces Directed to Downstream Dispersion Area - - - - - - square feet
20 Impervious Surfaces Not Directed to Downstream
Dispersion Area - - - - - - square feet
Result 21 Deficit of Effectively Treated Stormwater 0 0 0 0 0 0 cubic-feet Total Volume
Reductions
-Congratulations, all specified drainage basins and BMPs are in compliance with stormwater pollutant control requirements. Include 11x17 color prints of this summary sheet and supporting worksheet calculations as part of the SWQMP submittal package.

Summary of Stormwater Pollutant Control Calculations (V1.3) Initial DCV
Site Design
Volume
Reductions
General Info
BMP Volume
Reductions
Treatment
Train
False
All fields in this summary worksheet are populated based on previous user inputs. If applicable, drainage basin elements that require revisions and/or supplemental information outside the scope of these worksheets are highlighted in orange and summairzed in the red text below. If all drainage basins achieve full compliance without a need for supplemental information, a green message will appear below.

Summary Notes:

False
False
False
False
False
Barham Drive TW1
Tree Well Credit Worksheet - VR / DCV / HMP
DMA Total Area Impervious Pervious Adjusted Area
(sf) (sf) (sf) (sf)
A1 2,433 2,190 243 2,044 Total 2,433 2,044 sf AIA
Impervious C = 0.9 Gross 2,433 sf
Soil Type D BMP C' 0.84
Pervious C = 0.3 85th % 0.62 in
Vol Retention Target DCV 106 cf
Net Infiltration Rate No
Avg Annual Ret 4.50% HMP + Treatment
DCV Fraction 0.027 HMP Muliplier 3.70
Vol Retention (cf) 3 DCV x 391 cf Mature Tree Size 20 ft -dia
DCV Credit 180.0 cf
Mature Area 314.2 sf Soil Depth DCV Multiplier Required Soil Vol 628.3 cf (in) Type D Soils 30 2.90
Actual Surface Area 96 sf 31 2.94
Actual Depth 48 in 32 2.99
Actual Volume Provided 384 cf 33 3.03
Credit Ratio 61.1% 34 3.08
Tree Credit Earned 110 cf 35 3.12
Check DCV 36 3.17
Tree Credit Satisfies; 37 3.21
Vol Reduction = 3 Yes 38 3.26
DCV = 106 Yes 39 3.30
HMP = 391 No 40 3.34
Street Tree Options Mature Req'd Soil 41 3.39
Dia Credit Area Volume 42 3.43
5 10 19.6 39.3 43 3.48 10 40 78.5 157.1 44 3.52 15 100 176.7 353.4 45 3.57
20 180 314.2 628.3 46 3.61
25 290 490.9 981.8 47 3.66
30 420 706.9 1,413.7 48 3.70
DCV Multiplier for
Treatment HMP Compliance
I I
I -
I I
Barham Drive TW1 A
Tree Well Credit Worksheet - VR / DCV / HMP
DMA Total Area Impervious Pervious Adjusted Area
(sf) (sf) (sf) (sf)
A1A 2,433 2,190 243 2,044 Total 2,433 2,044 sf AIA
Impervious C = 0.9 Gross 2,433 sf
Soil Type D BMP C' 0.84
Pervious C = 0.3 85th % 0.62 in
Vol Retention Target DCV 106 cf
Net Infiltration Rate No
Avg Annual Ret 4.50% HMP + Treatment
DCV Fraction 0.027 HMP Muliplier 3.70
Vol Retention (cf) 3 DCV x 391 cf Mature Tree Size 20 ft -dia
DCV Credit 180.0 cf
Mature Area 314.2 sf Soil Depth DCV Multiplier Required Soil Vol 628.3 cf (in) Type D Soils 30 2.90
Actual Surface Area 96 sf 31 2.94
Actual Depth 48 in 32 2.99
Actual Volume Provided 384 cf 33 3.03
Credit Ratio 61.1% 34 3.08
Tree Credit Earned 110 cf 35 3.12
Check DCV 36 3.17
Tree Credit Satisfies; 37 3.21
Vol Reduction = 3 Yes 38 3.26
DCV = 106 Yes 39 3.30
HMP = 391 No 40 3.34
Street Tree Options Mature Req'd Soil 41 3.39
Dia Credit Area Volume 42 3.43
5 10 19.6 39.3 43 3.48 10 40 78.5 157.1 44 3.52 15 100 176.7 353.4 45 3.57
20 180 314.2 628.3 46 3.61
25 290 490.9 981.8 47 3.66
30 420 706.9 1,413.7 48 3.70
DCV Multiplier for
Treatment HMP Compliance
I I
I -
I I
Barham Drive TW2
Tree Well Credit Worksheet - VR / DCV / HMP
DMA Total Area Impervious Pervious Adjusted Area
(sf) (sf) (sf) (sf)
A3 2,217 1,774 443 1,729 Total 2,217 1,729 sf AIA
Impervious C = 0.9 Gross 2,217 sf
Soil Type D BMP C' 0.78
Pervious C = 0.3 85th % 0.62 in
Vol Retention Target DCV 89 cf
Net Infiltration Rate No
Avg Annual Ret 4.50% HMP + Treatment
DCV Fraction 0.027 HMP Muliplier 3.70
Vol Retention (cf) 2 DCV x 331 cf Mature Tree Size 20 ft -dia
DCV Credit 180.0 cf
Mature Area 314.2 sf Soil Depth DCV Multiplier Required Soil Vol 628.3 cf (in) Type D Soils 30 2.90
Actual Surface Area 80 sf 31 2.94
Actual Depth 48 in 32 2.99
Actual Volume Provided 320 cf 33 3.03
Credit Ratio 50.9% 34 3.08
Tree Credit Earned 92 cf 35 3.12
Check DCV 36 3.17
Tree Credit Satisfies; 37 3.21
Vol Reduction = 2 Yes 38 3.26
DCV = 89 Yes 39 3.30
HMP = 331 No 40 3.34
Street Tree Options Mature Req'd Soil 41 3.39
Dia Credit Area Volume 42 3.43
5 10 19.6 39.3 43 3.48 10 40 78.5 157.1 44 3.52 15 100 176.7 353.4 45 3.57
20 180 314.2 628.3 46 3.61
25 290 490.9 981.8 47 3.66
30 420 706.9 1,413.7 48 3.70
DCV Multiplier for
Treatment HMP Compliance
I I
I -
I I
Barham Drive TW2 A
Tree Well Credit Worksheet - VR / DCV / HMP
DMA Total Area Impervious Pervious Adjusted Area
(sf) (sf) (sf) (sf)
A3A 2,217 1,774 443 1,729 Total 2,217 1,729 sf AIA
Impervious C = 0.9 Gross 2,217 sf
Soil Type D BMP C' 0.78
Pervious C = 0.3 85th % 0.62 in
Vol Retention Target DCV 89 cf
Net Infiltration Rate No
Avg Annual Ret 4.50% HMP + Treatment
DCV Fraction 0.027 HMP Muliplier 3.70
Vol Retention (cf) 2 DCV x 331 cf Mature Tree Size 20 ft -dia
DCV Credit 180.0 cf
Mature Area 314.2 sf Soil Depth DCV Multiplier Required Soil Vol 628.3 cf (in) Type D Soils 30 2.90
Actual Surface Area 80 sf 31 2.94
Actual Depth 48 in 32 2.99
Actual Volume Provided 320 cf 33 3.03
Credit Ratio 50.9% 34 3.08
Tree Credit Earned 92 cf 35 3.12
Check DCV 36 3.17
Tree Credit Satisfies; 37 3.21
Vol Reduction = 2 Yes 38 3.26
DCV = 89 Yes 39 3.30
HMP = 331 No 40 3.34
Street Tree Options Mature Req'd Soil 41 3.39
Dia Credit Area Volume 42 3.43
5 10 19.6 39.3 43 3.48 10 40 78.5 157.1 44 3.52 15 100 176.7 353.4 45 3.57
20 180 314.2 628.3 46 3.61
25 290 490.9 981.8 47 3.66
30 420 706.9 1,413.7 48 3.70
DCV Multiplier for
Treatment HMP Compliance
I I
I -
I I
Barham Drive TW3
Tree Well Credit Worksheet - VR / DCV / HMP
DMA Total Area Impervious Pervious Adjusted Area
(sf) (sf) (sf) (sf)
A4 11,478 6,657 4,821 7,438 Total 11,478 7,438 sf AIA
Impervious C = 0.9 Gross 11,478 sf
Soil Type D BMP C' 0.65
Pervious C = 0.3 85th % 0.62 in
Vol Retention Target DCV 384 cf
Net Infiltration Rate No
Avg Annual Ret 4.50% HMP + Treatment
DCV Fraction 0.027 HMP Muliplier 3.70
Vol Retention (cf) 10 DCV x 1,422 cf Mature Tree Size 30 ft -dia
DCV Credit 420.0 cf
Mature Area 706.9 sf Soil Depth DCV Multiplier Required Soil Vol 1,413.7 cf (in) Type D Soils
30 2.90
Actual Surface Area 336 sf 31 2.94
Actual Depth 48 in 32 2.99
Actual Volume Provided 1344 cf 33 3.03
Credit Ratio 95.1% 34 3.08
Tree Credit Earned 399 cf 35 3.12
Check DCV 36 3.17
Tree Credit Satisfies; 37 3.21
Vol Reduction = 10 Yes 38 3.26
DCV = 384 Yes 39 3.30
HMP = 1,422 No 40 3.34
Street Tree Options Mature Req'd Soil 41 3.39
Dia Credit Area Volume 42 3.43
5 10 19.6 39.3 43 3.48 10 40 78.5 157.1 44 3.52 15 100 176.7 353.4 45 3.57
20 180 314.2 628.3 46 3.61
25 290 490.9 981.8 47 3.66
30 420 706.9 1,413.7 48 3.70
DCV Multiplier for
Treatment HMP Compliance
I I
I -
I I
City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020

ATTACHMENT 2

BACKUP FOR PDP HYDROMODIFICATION CONTROL MEASURES

This is the cover sheet for Attachment 2.

Mark this box if this attachment is empty because the project is exempt from PDP hydromodification management requirements.

Indicate which Items are Included behind this cover sheet:

Attachment
Sequence
Contents Checklist
Attachment 2a Hydromodification Management Exhibit
(Required)

See DMA Exhibit

See Hydromodification Management
Exhibit Checklist on the back of this
Attachment cover sheet.

Attachment 2 b Management of Critical Coarse Sediment
Yield Areas (WMAA Exhibit is required,
additional analyses are optional)

See Section 6.2 of the BMP Design
Manual.
☒ Exhibit showing p roject drainage
boundaries marked on WMAA Critical
Coarse Sediment Yield Area Map
(Required)

Optional analyses for Critical Coarse
Sediment Yield Area Determination
6.2.1 Verification of Geomorphic
Landscape Units Onsite
6.2.2 Downstream Systems
Sensitivity to Coarse Sediment
6.2.3 Optional Additional Analysis of
Potential Critical Coarse Sediment
Yield Areas Onsite

Attachment 2 c Geomorphic Assessment of Receiving
Channels (Optional)
See Section 6.3.4 of the BMP Design
Manual.
☒ Not performed
Included
Submitted as separate stand-alone
document

Attachment 2 d Flow Control Facility Design , including Structural BMP Drawdown Calculations
and Overflow Design Summary
(Required)
See Chapter 6 and Appendix G of the
BMP Design Manual
☒ Inc luded
Submitted as separate stand-alone
document
See attached SWMM Report
Attachment 2e Vector Control Plan (Required when
structural BMPs will not drain in 96
hours)
Included
☒ Not required because BMPs will
drain in less than 96 hours

City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020

Use this checklist to ensure the required information has been included on the Hydromodification Management Exhibit:

The Hydromodification Management Exhibit must identify:

Underlying hydrologic soil group
Approximate depth to groundwater
Existing natural hydrologic features ( watercourses, seeps, springs, wetlands) Critical coarse sediment yield areas to be protected
Existing topography
Existing and proposed site drainage network and connections to drainage offsite Proposed grading
Proposed impervious features
Proposed design features and surface treatments used to minimize imperviousness Point(s) of Compliance (POC) for Hydromodification Management Existing and proposed drainage boundary and drainage area to each POC (when necessary, create separate exhibits for pre-development and post-project conditions) Structural BMPs for hydromodification management (identify location, type of BMP, and size/detail)

Barham Drive
Potential CCSYA
800 ft
N ➤ ➤
N
© 2019 Google
© 2019 Google
© 2019 Google

ATTACHMENT

S.W.M.M. ~ HMP CONTINUOUS SIMULATION MODEL FOR:

943 BARHAM DRIVE

CITY OF SAN MARCOS, CA

July 2, 2020

PREPARED BY:

3990 RUFFIN ROAD, SUITE 120
SAN DIEGO, CA 92123
858-560-1141

SB&O~

PLANNING ENGINEERING SURVEYING

i SB&O Inc.
943 BARHAM DRIVE (858) 560-1141
S.W.M.M. ~ HMP CONTINUOUS SIMULATION
www.SBOINC.com

TABLE OF CONTENTS

INTRODUCTION ............................................................................................................. 1 STORM WATER MANAGEMENT MODEL SOFTWARE ................................................ 1 POINT OF COMPLIANCE (POC).................................................................................... 2 ANALYSIS ....................................................................................................................... 2 RAINFALL DATA............................................................................................................. 2 EVAPORATION .............................................................................................................. 3 SUBCATCHMENTS ........................................................................................................ 3 STORAGE UNITS ........................................................................................................... 6 STATISTICS ................................................................................................................... 6 RESULTS .............................................................................................. ..................................... 7

1 SB&O Inc.
“943 BARHAM DRIVE” (858) 560-1141
S.W.M.M. ~ HMP CONTINUOUS SIMULATION
www.SBOINC.com

INTRODUCTION

This report, “S.W.M.M. ~ HMP CONTINUOUS SIMULATION MODELING FOR 943 BARHAM DRIVE”, is an attachment to the project Storm Water Quality Management Plan (SWQMP) and is not intended to be an independent document.

The San Diego County final Hydromodification Management Plan (HMP) became effective in January of 2011, and is applicable to all priority projects regardless of size. The HMP model seeks to limit post development increases in runoff (magnitude and duration) for runoff event ranging from a fraction of the Q2 up to Q10.

Hydromodification flow control is achieved for this project by routing runoff through the HMP control facility (basins). Outflow is restricted by using multiple control openings at each discharge. To determine the hydromodification controls and tank dimensions, Continuous Simulation Modeling was done using the EPA Storm Water Management Model (SWMM) software. Separate reports have been prepared to analyze the onsite 100-year storm capacity and to analyze the capacity of the downstream public drainage system.

STORM WATER MANAGEMENT MODEL SOFTWARE

EPA's Storm Water Management Model (SWMM) was first developed in 1971, and has since undergone several major upgrades. It continues to be widely used throughout the world for planning, analysis and design related to stormwater runoff, combined sewers, sanitary sewers, and other drainage systems in urban areas, with many applications in non-urban areas as well.

This general purpose urban hydrology and conveyance system hydraulics software is a dynamic rainfall-runoff simulation model used for single event or long-term (continuous) simulation of runoff quantity and quality from primarily urban areas. The runoff component of SWMM operates on a collection of subcatchment areas that receive precipitation and generate runoff and pollutant loads. The routing portion of SWMM transports this runoff through a system of pipes, channels, storage/treatment devices, pumps, and regulators. SWMM tracks the quantity and quality of runoff generated within each subcatchment, and the flow rate, flow depth, and quality of water in each pipe and channel during a simulation period comprised of multiple time steps.

EPA has recently extended SWMM 5 to explicitly model the hydrologic performance of specific types of low impact development (LID) controls, such as porous pavement, bio-retention areas (e.g., rain gardens, green roofs, and street planters), rain barrels, infiltration trenches, and vegetative swales. The updated model allows engineers and planners to accurately represent any combination of LID controls within a study area to determine their effectiveness in managing stormwater and combined sewer overflows.

SWMM 5 was produced in a joint development effort with CDM, Inc., a global consulting, engineering, construction, and operations firm.

2 SB&O Inc.
“943 BARHAM DRIVE” (858) 560-1141
S.W.M.M. ~ HMP CONTINUOUS SIMULATION
www.SBOINC.com

POINT OF COMPLIANCE (POC)

The majority of the developed runoff will be conveyed by the site private storm drain system to the northwest corner of the site for treatment and flow control (HMP & Detention). The proposed basin which will discharge to the existing storm drain system in Barham Road.

Due to the hillside nature of the development, runoff from the steep driveway entries and frontage slopes will discharge to the Barham gutter. These flow will be intercepted by a proposed inlet on Barham Road near the northwest corner of the site.

The uphill section of the project will include manufactured cut slopes at the existing hillside. Runoff from the existing and proposed slopes will be intercepted in the bypass drainage ditches and storm drain, then directed to the westerly limits and then conveyed to a proposed inlet near the northwest corner of the property, which is connected to the existing Barham storm drain (MS-4).

Assuming the default low-flow threshold of 0.1 Q2, we have assigned one POC to the project, as shown on the DMA Exhibit. The location of the POC is consistent with the pre-development condition.

ANALYSIS

For each of the POCs, two models were simulated: pre-development and post-development mitigated. The pre-development condition simulation is a representation of the undeveloped site. The post-developed site adds BMPs and the detention facilities to reduce flows to meet the HMP requirements.

The performance standard requires the following:

1. For flow rates from 10% of the pre-project 2-yea r runoff event (0.1Q2) to the pre-project 10-year runoff event (Q10), the post-project discharge rates and durations shall not deviate above the pre-project rates and durations by more than 10% over more than 10% of the length of the flow duration curve.

2. For flow rates from 0.1 Q2 to Q5, the post-proje ct peak flows shall not exceed pre- project peak flows. For flow rates from Q5 to Q10, post-project peak flows may exceed pre-project flows by up to 10% for a 1-year frequency interval. For example, post-project flows could exceed pre-project flows by up to 10% for the interval from Q9 to Q10 or from Q5.5 to Q6.5, but not from Q8 to Q10.

RAINFALL DATA

Precipitation is the principal driving variable in rainfall-runoff-quantity simulation. The volume and rate of stormwater runoff depends directly on the precipitation magnitude, and its spatial and temporal distribution over the catchment. Each subcatchment in SWMM is linked to a Rain Gage object that describes the format and source of the rainfall input for the subcatchment. The same rain gage and time series is applied to all scenarios for this project.

Long-term hourly rainfall records have been prepared for the San Diego rainfall stations.

Sources of the rainfall data include ALERT data from the County of San Diego (which extend

3 SB&O Inc.
“943 BARHAM DRIVE” (858) 560-1141
S.W.M.M. ~ HMP CONTINUOUS SIMULATION
www.SBOINC.com

back to 1982), the California Climatic Data Archive, National Oceanic and Atmospheric Administration (NOAA), the National Climatic Data Center, and the Western Regional Climate Center. In all cases, the length of the overall rainfall station record is 35 years or the overall length of the rainfall record, whichever is longer. The ESCONDIDO ALERT Station rainfall data was used for this project and can be found at, www.projectcleanwater.org .

ESCONDIDO RESERVOIR was chosen for this site due to its geographic proximity and similarity in elevation to this site.

EVAPORATION

Single event simulations are usually insensitive to the evaporation rate. Thus, evaporation is typically neglected when a single rainfall event or a synthetic storm is simulated. However, this process is more significant when a continuous simulation is performed because it is through evaporation that depression storage is recovered and water levels in extended detention and wet ponds are reduced; thus it becomes an important component of the overall water budget.

This project is located in the California Irrigation Management Information System (CIMIS) Zone 6. Monthly averages are applied to this site as provided by CIMIS.

SUBCATCHMENTS

SWMM is a distributed model, which means that a study area can be subdivided into any number of irregular subcatchments to best capture the effect that spatial variability in topography, drainage pathways, land cover, and soil characteristics have on runoff generation.

Each subcatchment can be further divided into three subareas: an impervious area with depression (detention) storage, an impervious area without depression storage, and a pervious area with depression storage. Only the latter area allows for rainfall losses due to infiltration into the soil. Described below are some of the characteristics of a subcatchment.

Width/Length

W = AREA ÷ LENGTH OF OVERLAND FLOW

The width can be defined as the subcatchment area divided by the length of the longest un- concentrated overland flow path that water can travel. If there are several such paths, then one would use an average of their lengths to compute a width. In urbanized catchments, true overland flow can be very short before it is collected into channels or pipes.

Slope
This is the slope of the land surface over which runoff flows, and is the same for both the pervious and impervious surfaces. It is the slope of what one considers to be the overland flow path, or its area-weighted average, if there are several such paths in the subcatchment.

The existing site is vacant and includes a hillside along the southern limits. Drainage is “natural” and generally overland toward the Barham Road frontage with an approximate grade of 6%.

4 SB&O Inc.
“943 BARHAM DRIVE” (858) 560-1141
S.W.M.M. ~ HMP CONTINUOUS SIMULATION
www.SBOINC.com

The proposed site has variable grades throughout the development. Area P1 is graded to an average slope of 2%, while area P-2 bypasses HMP treatment and is graded to an average of 10%.

Imperviousness
This is the percentage of the subcatchment area that is covered by impervious surfaces, such as roofs and roadways, through which rainfall cannot infiltrate. Imperviousness tends to be the most sensitive parameter in the hydrologic characterization of a catchment, and can range anywhere from 0% for undeveloped areas up to 100% for high-density areas.

The existing site is 100% pervious undeveloped site.

The developed condition for P-1 is approximately 80% impervious and the on-site bypass P-2 is approximately 30% impervious.

Roughness Coefficient
The roughness coefficient reflects the amount of resistance that overland flow encounters as it runs off of the subcatchment surface. Since SWMM uses the Manning equation to compute the overland flow rate, this coefficient is the same as Manning’s roughness coefficient n. Separate values are required for the impervious and pervious fractions of a subcatchment since the pervious n is generally an order of magnitude higher than the impervious n.

N-imperv = 0.012
N-perv = 0.15

Depression Storage “Dstore”
Depression storage corresponds to a volume that must be filled prior to the occurrence of any runoff. Different values can be used for the pervious and impervious areas of a subcatchment. It represents initial abstractions such as surface ponding, interception by flat roofs and vegetation, and surface wetting.

Typical “D” values:

Surface D (in)
Impervious surfaces (AC,PCC) 0.05
Proposed Landscaping 0.10
Existing Natural Terrain 0.15

Percent of Impervious Area without Depression Storage
This parameter accounts for immediate runoff that occurs at the beginning of rainfall before depression storage is satisfied. It represents pavement close to the gutters that has no surface storage, pitched rooftops that drain directly to street gutters, new pavement that may not have surface ponding, etc. By default the value of this variable is 25%, but it can be changed in each subcatchment. Unless special circumstances are known to exist, a percent imperviousness area without depression storage of 25% is recommended.

Subarea Routing
Choice of internal routing of runoff between pervious and impervious areas:

IMPERVIOUS: Runoff from pervious areas flow to impervious areas PERVIOUS: Runoff from impervious areas flow to pervious areas.

5 SB&O Inc.
“943 BARHAM DRIVE” (858) 560-1141
S.W.M.M. ~ HMP CONTINUOUS SIMULATION
www.SBOINC.com

OUTLET: Runoff from both areas flow directly to outlets.

This project utilizes only the OUTLET routing option, as recommended in the San Diego County BMP Design Manual.

Percent Routed
The percentage of runoff from the subcatchment that is to be routed. In all cases this is 100%.

Infiltration Model
Three different methods for computing infiltration loss on the pervious areas of a subcatchment are available in SWMM. They are the Horton, Green-Ampt and Curve Number models. There is no general agreement on which model is best. The Horton model has a long history of use in dynamic simulations, the Green-Ampt model is more physically-based, and the Curve Number model is derived from (but not the same as) the well-known SCS Curve Number method used in simplified runoff models.

We have chosen to use the Green-Ampt model for this project for type “D” soil:

Suction Head = 9.0 inches
Conductivity = 0.025
Initial Deficit = 0.3

Low Impact Development (LID) Controls
LID Controls are low impact development practices designed to capture surface runoff and provide some combination of detention, infiltration, and evapotranspiration. They are considered as properties of a given subcatchment, similar to how Aquifers and Snow Packs are treated.

SWMM can explicitly model five different generic types of LID controls: Bio-retention Cells (with impermeable liner option), Infiltration Trenches, Continuous Porous Pavement Systems, Rain Barrels (or Cisterns) and Vegetative Swales.

Bio-retention cells, infiltration trenches, and porous pavement systems can all contain optional underdrain systems in their gravel storage beds to convey captured runoff off of the site rather than letting it all infiltrate. They can also have an impermeable floor or liner that prevents any infiltration into the native soil from occurring. Infiltration trenches and porous pavement systems can also be subject to a decrease in hydraulic conductivity over time due to clogging.

This project models BMPs as Bio-Retention Cells with a liner on the sides. The program is setup to route all flows from a Subcatchment into a smaller subcatchment that is fully occupied by the LID control. The project geotechnical engineer has found that infiltration is minimal, so the on-site BMP is lined on the sides.

STORAGE

SWMM routes runoff through storage units such as ponds and tanks with outlet orifices and weirs. Tanks can be modeled using either a storage curve function or a depth-area table. For this project we inputted a depth-area table and do allow for storage infiltration.

6 SB&O Inc.
“943 BARHAM DRIVE” (858) 560-1141
S.W.M.M. ~ HMP CONTINUOUS SIMULATION
www.SBOINC.com

The project is required to provide water quality treatment and flow control for post development runoff. The project proposes a surface biofiltration basin with enhanced below grade storage to provide treatment and flow control. The surface basin has additional storage depth and an overflow structure with both a weir opening and grated top to provide attenuation of larger storm events. A concrete lined ramp provides an emergency overflow path to the driveway and then Barham Drive. In order to ensure that post development flows do not exceed existing peak flows, detention routing analyses were prepared to determine peak outflows, and to provide adjusted discharge estimate for comparison to the existing condition.

The project proposes two open bottom underground storage tanks to provide treatment and volume retention by allowing infiltration of the water quality volume (DCV) and to accomplish flow control (HMP) by eliminating the usual low flow orifice and using only an overflow weir.

Raw test results of the surficial soils indicate very poor rates (<0.05”/hr.). However, the bottom of the BMP has been left unlined to attain infiltration on the low flows

Main Basin Storage 54,724 cf. (1.26 ac-ft) @ 4.95’ surface depth Elevation Description Dimension/ Size Comment
647.15 Bottom of Crushed Rock 6,764 sf 40% V oid Ratio 647.15 Low Flow Orifice 2” dia .
648.15 Bottom of Soil Layer 6,764 sf 30% V oid Ratio 650.15 Floor of Surface Basin 6,764 sf
650.65 surface depth @ 6” 7,330 sf Treatment Surface Area 653.90 3” overflow opening 11,027 sf 3. 75’ surface depth 654. 60 Grated overflow 5’ x5’ 11,931 sf 4.45’ surface depth 655.10 Surface Overflow 12,594 sf 4. 95’ surface depth 656.10 Top of Earth Berm 14,575 sf 5. 95’ surface depth

STATISTICS

SWMM computes peak flow frequency statistics by constructing a partial-duration series. This involves examining the entire runoff time series generated by the model, dividing the runoff time series into a set of discrete unrelated events, determining the peak flow for each event, ranking the peak flows for all events and then computing the recurrence interval or plotting position for each storm event. A separation event, defined as a time period in which runoff does not exceed a prescribed threshold, is required to parse the long-term flow records into discrete runoff events. The separation event corresponds to the required number of consecutive time intervals (24 hours in this case) with a flow value less than Flow Floor 1 (0.002 cfs/acre).

SWMM uses the Weibull method for construction of the partial-duration series, but the Final HMP gives preference to the Cunnane method. Both the Weibull and Cunnane methods result in very similar return periods and frequencies for events that occur below the Q10, and do not

7 SB&O Inc.
“943 BARHAM DRIVE” (858) 560-1141
S.W.M.M. ~ HMP CONTINUOUS SIMULATION
www.SBOINC.com

begin significantly contrasting until the low frequency (high flow) ranges. We have converted the SWMM partial duration series to a Cunnane plotting for this report and have included a table at the end of this report.

AREA SUMMARY

TOTAL BMP IMPERV PERVIOUS IMP. %
PRE- 8.828 0.0000 0.0000 8.828 0
POST- 8.828 0. 456 5.576 2.391 68%
NOTE: ALL AREAS SHOWN IN ACRES

*Note: 1.40 Acres of the site does not flow through the BMP structure, however the overall combined storage is satisfied through the BMP.

RESULTS

For each HMP facility (each POC) the results are included at the end of this report and are summarized as follows:

A. PEAK FLOW-EXCEEDANCE CURVE
B. RUNOFF-DURATION CURVE (LOGARITHMIC)
C. FLOW-DURATION DATA TABLE
D. PEAK EVENT TABLE – EXISTING (INCLUDES Q2-Q10 THR ESHOLDS) E. PEAK EVENT TABLE – POST-MITIGATED

Observing flows between 0.1Q2 and Q10, each of thes e charts or tables show the flow control openings for the project HMP facility reduces the runoff from the site to below the pre-developed condition, and meets the performance standard requirements described above.

“943 BARHAM DRIVE” SB&O Inc.

S.W.M.M. ~ HMP CONTINUOUS SIMULATION (858) 560-1141

www.SBOINC.com

APPENDIX I: POC #1 SWMM RESULTS

A. PEAK FLOW-EXCEEDANCE CURVE
B. RUNOFF-DURATION CURVE (LOGARITHMIC)
C. FLOW-DURATION DATA TABLE
D. PEAK EVENT TABLE – EXISTING (INCLUDES Q2-Q10 THR ESHOLDS) E. PEAK EVENT TABLE – POST-MITIGATED
F. POND STAGE-STORAGE-DISCHARGE TABLE

0.000

1.000

2.000

0.00E+00 1.00E-03 2.00E-03

PEAK FLOW (CFS)
% EXCEEDENCE
P .O.C. 1: FLOW EXCEEDENCE

PRE-DEV

POST-MIT
Q10

0.1Q2
t t
.

I I I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I

0.000

1.000

2.000
1 100

PEAK FLOW (CFS)

DURATION (HRS)
P .O.C. 1: DURATION

PRE-DEV

POST-MIT
Q10

0.1Q2
t f i :

POC. #1: FLOW-DURATION TABLE
Q2 = 2.941 CFS FRACTION = 1.0%

0.1Q2= 0.2941 CFS
Q10 = 4.768 CFS
STEP = 0.045 CFS

PERCENT PASS OR
INTERVAL Q (CFS) HRS>Q % EXCEEDED HRS>Q % EXCEEDED POST/PRE FAIL 0 0.294 1054 2.75E-03 879 2.30E-03 83% PASS
1 0.339 971 2.54E-03 710 1.86E-03 73% PASS
2 0.384 885 2.31E-03 607 1.59E-03 69% PASS
3 0.428 811 2.12E-03 532 1.39E-03 66% PASS
4 0.473 747 1.95E-03 466 1.22E-03 62% PASS
5 0.518 684 1.79E-03 425 1.11E-03 62% PASS
6 0.563 639 1.67E-03 399 1.04E-03 62% PASS
7 0.607 597 1.56E-03 371 9.69E-04 62% PASS
8 0.652 556 1.45E-03 344 8.99E-04 62% PASS
9 0.697 520 1.36E-03 323 8.44E-04 62% PASS
10 0.742 490 1.28E-03 298 7.79E-04 61% PASS
11 0.786 452 1.18E-03 271 7.08E-04 60% PASS
12 0.831 419 1.09E-03 258 6.74E-04 62% PASS
13 0.876 398 1.04E-03 247 6.45E-04 62% PASS
14 0.920 372 9.72E-04 228 5.96E-04 61% PASS
15 0.965 347 9.07E-04 219 5.72E-04 63% PASS
16 1.010 326 8.52E-04 215 5.62E-04 66% PASS
17 1.055 306 8.00E-04 202 5.28E-04 66% PASS
18 1.099 282 7.37E-04 195 5.09E-04 69% PASS
19 1.144 269 7.03E-04 189 4.94E-04 70% PASS
20 1.189 245 6.40E-04 181 4.73E-04 74% PASS
21 1.234 232 6.06E-04 175 4.57E-04 75% PASS
22 1.278 224 5.85E-04 169 4.42E-04 75% PASS
23 1.323 209 5.46E-04 160 4.18E-04 77% PASS
24 1.368 198 5.17E-04 154 4.02E-04 78% PASS
25 1.413 190 4.96E-04 143 3.74E-04 75% PASS
26 1.457 182 4.76E-04 138 3.61E-04 76% PASS
27 1.502 166 4.34E-04 129 3.37E-04 78% PASS
28 1.547 155 4.05E-04 119 3.11E-04 77% PASS
29 1.592 149 3.89E-04 109 2.85E-04 73% PASS
30 1.636 140 3.66E-04 106 2.77E-04 76% PASS
31 1.681 136 3.55E-04 102 2.67E-04 75% PASS
32 1.726 128 3.34E-04 100 2.61E-04 78% PASS
33 1.771 116 3.03E-04 96 2.51E-04 83% PASS
34 1.815 113 2.95E-04 90 2.35E-04 80% PASS
35 1.860 108 2.82E-04 88 2.30E-04 81% PASS
36 1.905 101 2.64E-04 84 2.19E-04 83% PASS
37 1.950 97 2.53E-04 79 2.06E-04 81% PASS
38 1.994 91 2.38E-04 76 1.99E-04 84% PASS
39 2.039 89 2.33E-04 73 1.91E-04 82% PASS
40 2.084 84 2.19E-04 70 1.83E-04 83% PASS
41 2.129 79 2.06E-04 66 1.72E-04 84% PASS
42 2.173 76 1.99E-04 62 1.62E-04 82% PASS
43 2.218 72 1.88E-04 61 1.59E-04 85% PASS
44 2.263 71 1.86E-04 60 1.57E-04 85% PASS
45 2.307 68 1.78E-04 58 1.52E-04 85% PASS
46 2.352 67 1.75E-04 57 1.49E-04 85% PASS
47 2.397 66 1.72E-04 54 1.41E-04 82% PASS
48 2.442 63 1.65E-04 50 1.31E-04 79% PASS

EXISTING POST-MITIGATED
D:\75051 Barham Drive\13 Reports\In-house Prelim Reports\SWMM\BARHAM, POC 1 SUMMARY, 2020-0430 7/1/2020 71132.60 49 2.486 60 1.57E-04 49 1.28E-04 82% PASS
50 2.531 56 1.46E-04 48 1.25E-04 86% PASS
51 2.576 52 1.36E-04 47 1.23E-04 90% PASS
52 2.621 51 1.33E-04 46 1.20E-04 90% PASS
53 2.665 50 1.31E-04 43 1.12E-04 86% PASS
54 2.710 47 1.23E-04 42 1.10E-04 89% PASS
55 2.755 46 1.20E-04 37 9.67E-05 80% PASS
56 2.800 42 1.10E-04 35 9.14E-05 83% PASS
57 2.844 40 1.05E-04 34 8.88E-05 85% PASS
58 2.889 40 1.05E-04 30 7.84E-05 75% PASS
59 2.934 37 9.67E-05 29 7.58E-05 78% PASS
60 2.979 34 8.88E-05 29 7.58E-05 85% PASS
61 3.023 32 8.36E-05 29 7.58E-05 91% PASS
62 3.068 31 8.10E-05 29 7.58E-05 94% PASS
63 3.113 29 7.58E-05 27 7.05E-05 93% PASS
64 3.158 29 7.58E-05 23 6.01E-05 79% PASS
65 3.202 28 7.32E-05 22 5.75E-05 79% PASS
66 3.247 28 7.32E-05 19 4.96E-05 68% PASS
67 3.292 28 7.32E-05 19 4.96E-05 68% PASS
68 3.337 26 6.79E-05 19 4.96E-05 73% PASS
69 3.381 25 6.53E-05 18 4.70E-05 72% PASS
70 3.426 23 6.01E-05 18 4.70E-05 78% PASS
71 3.471 23 6.01E-05 17 4.44E-05 74% PASS
72 3.516 22 5.75E-05 17 4.44E-05 77% PASS
73 3.560 21 5.49E-05 17 4.44E-05 81% PASS
74 3.605 19 4.96E-05 17 4.44E-05 89% PASS
75 3.650 19 4.96E-05 17 4.44E-05 89% PASS
76 3.694 19 4.96E-05 16 4.18E-05 84% PASS
77 3.739 19 4.96E-05 15 3.92E-05 79% PASS
78 3.784 18 4.70E-05 15 3.92E-05 83% PASS
79 3.829 18 4.70E-05 15 3.92E-05 83% PASS
80 3.873 17 4.44E-05 13 3.40E-05 76% PASS
81 3.918 16 4.18E-05 13 3.40E-05 81% PASS
82 3.963 16 4.18E-05 13 3.40E-05 81% PASS
83 4.008 15 3.92E-05 11 2.87E-05 73% PASS
84 4.052 14 3.66E-05 9 2.35E-05 64% PASS
85 4.097 13 3.40E-05 9 2.35E-05 69% PASS
86 4.142 13 3.40E-05 9 2.35E-05 69% PASS
87 4.187 13 3.40E-05 9 2.35E-05 69% PASS
88 4.231 13 3.40E-05 9 2.35E-05 69% PASS
89 4.276 12 3.14E-05 8 2.09E-05 67% PASS
90 4.321 10 2.61E-05 7 1.83E-05 70% PASS
91 4.366 9 2.35E-05 6 1.57E-05 67% PASS
92 4.410 9 2.35E-05 5 1.31E-05 56% PASS
93 4.455 9 2.35E-05 5 1.31E-05 56% PASS
94 4.500 8 2.09E-05 4 1.05E-05 50% PASS
95 4.545 7 1.83E-05 4 1.05E-05 57% PASS
96 4.589 7 1.83E-05 4 1.05E-05 57% PASS
97 4.634 7 1.83E-05 4 1.05E-05 57% PASS
98 4.679 6 1.57E-05 3 7.84E-06 50% PASS
99 4.724 6 1.57E-05 3 7.84E-06 50% PASS
100 4.768 4 1.05E-05 3 7.84E-06 75% PASS
D:\75051 Barham Drive\13 Reports\In-house Prelim Reports\SWMM\BARHAM, POC 1 SUMMARY, 2020-0430 7/1/2020 71132.60 P.O.C. #1: PEAK EVENTS - EXISTING

WEIBULL (SWMM) CUNNANE
F = m/(nr+1) where F = frequency F = (i-0.4)/(n+0.2)
m = event rank i = rank
nr = total number of event n = sample size = # of storms n = number of year anlayzed
Number of Years Analyzed (n): 43.69
Total number of events (nr) 246
m or i F Return (yrs) F Return Q Q2 2.941
1 0.40% 44.69 0.24% 73.15 6.164 Q3 3.382
2 0.81% 22.35 0.65% 27.43 5.419 Q4 3.825
3 1.21% 14.90 1.06% 16.88 4.867 Q5 4.228
4 1.62% 11.17 1.46% 12.19 4.781 Q6 4.386
5 2.02% 8.94 1.87% 9.54 4.765 Q7 4.596
6 2.43% 7.45 2.27% 7.84 4.736 Q8 4.739
7 2.83% 6.38 2.68% 6.65 4.528 Q9 4.759
8 3.24% 5.59 3.09% 5.78 4.330 Q10 4.768
9 3.64% 4.97 3.49% 5.10 4.282
10 4.05% 4.47 3.90% 4.57 3.893 START 9/24/1964 13:00
11 4.45% 4.06 4.31% 4.14 3.863 END 5/23/2008 22:00
12 4.86% 3.72 4.71% 3.78 3.759 TOTAL YRS 43.69
13 5.26% 3.44 5.12% 3.48 3.537 TOTAL HRS 382737
14 5.67% 3.19 5.52% 3.23 3.383
15 6.07% 2.98 5.93% 3.01 3.382
16 6.48% 2.79 6.34% 2.81 3.299
17 6.88% 2.63 6.74% 2.64 3.298
18 7.29% 2.48 7.15% 2.49 3.111
19 7.69% 2.35 7.55% 2.36 3.088
20 8.10% 2.23 7.96% 2.24 2.996
21 8.50% 2.13 8.37% 2.13 2.974
22 8.91% 2.03 8.77% 2.03 2.941
23 9.31% 1.94 9.18% 1.94 2.930
24 9.72% 1.86 9.59% 1.86 2.899
25 10.12% 1.79 9.99% 1.78 2.787
26 10.53% 1.72 10.40% 1.71 2.772
27 10.93% 1.66 10.80% 1.65 2.758
28 11.34% 1.60 11.21% 1.59 2.676
29 11.74% 1.54 11.62% 1.53 2.630
30 12.15% 1.49 12.02% 1.48 2.565
31 12.55% 1.44 12.43% 1.43 2.552
32 12.96% 1.40 12.84% 1.39 2.538
33 13.36% 1.35 13.24% 1.35 2.493
34 13.77% 1.31 13.65% 1.31 2.468
35 14.17% 1.28 14.05% 1.27 2.415
36 14.57% 1.24 14.46% 1.23 2.411
37 14.98% 1.21 14.87% 1.20 2.311
38 15.38% 1.18 15.27% 1.17 2.242
39 15.79% 1.15 15.68% 1.14 2.211
40 16.19% 1.12 16.08% 1.11 2.153
41 16.60% 1.09 16.49% 1.08 2.128
42 17.00% 1.06 16.90% 1.06 2.114
43 17.41% 1.04 17.30% 1.03 2.112
44 17.81% 1.02 17.71% 1.01 2.053
Cunnane Weibull PEAK EVENTS

SUMMARY OF
I I I

I I I I I I
45 18.22% 0.99 18.12% 0.98 1.975
46 18.62% 0.97 18.52% 0.96 1.886
47 19.03% 0.95 18.93% 0.94 1.857
48 19.43% 0.93 19.33% 0.92 1.842
49 19.84% 0.91 19.74% 0.90 1.790
50 20.24% 0.89 20.15% 0.88 1.745
51 20.65% 0.88 20.55% 0.87 1.743
52 21.05% 0.86 20.96% 0.85 1.737
53 21.46% 0.84 21.36% 0.83 1.734
54 21.86% 0.83 21.77% 0.82 1.704
55 22.27% 0.81 22.18% 0.80 1.686
56 22.67% 0.80 22.58% 0.79 1.674
57 23.08% 0.78 22.99% 0.78 1.632
58 23.48% 0.77 23.40% 0.76 1.612
59 23.89% 0.76 23.80% 0.75 1.610
60 24.29% 0.74 24.21% 0.74 1.568
61 24.70% 0.73 24.61% 0.72 1.561
62 25.10% 0.72 25.02% 0.71 1.542
63 25.51% 0.71 25.43% 0.70 1.540
64 25.91% 0.70 25.83% 0.69 1.539
65 26.32% 0.69 26.24% 0.68 1.526
66 26.72% 0.68 26.65% 0.67 1.507
67 27.13% 0.67 27.05% 0.66 1.492
68 27.53% 0.66 27.46% 0.65 1.489
69 27.94% 0.65 27.86% 0.64 1.469
70 28.34% 0.64 28.27% 0.63 1.466
71 28.74% 0.63 28.68% 0.62 1.462
72 29.15% 0.62 29.08% 0.61 1.438
73 29.55% 0.61 29.49% 0.60 1.438
74 29.96% 0.60 29.89% 0.60 1.437
75 30.36% 0.60 30.30% 0.59 1.432
76 30.77% 0.59 30.71% 0.58 1.382
77 31.17% 0.58 31.11% 0.57 1.357
78 31.58% 0.57 31.52% 0.57 1.353
79 31.98% 0.57 31.93% 0.56 1.325
80 32.39% 0.56 32.33% 0.55 1.311
81 32.79% 0.55 32.74% 0.54 1.303
82 33.20% 0.55 33.14% 0.54 1.287
83 33.60% 0.54 33.55% 0.53 1.252
84 34.01% 0.53 33.96% 0.53 1.211
85 34.41% 0.53 34.36% 0.52 1.208
86 34.82% 0.52 34.77% 0.51 1.206
87 35.22% 0.51 35.17% 0.51 1.197
88 35.63% 0.51 35.58% 0.50 1.187
89 36.03% 0.50 35.99% 0.50 1.182
90 36.44% 0.50 36.39% 0.49 1.179
91 36.84% 0.49 36.80% 0.48 1.177
92 37.25% 0.49 37.21% 0.48 1.172
93 37.65% 0.48 37.61% 0.47 1.172
94 38.06% 0.48 38.02% 0.47 1.170
95 38.46% 0.47 38.42% 0.46 1.166
96 38.87% 0.47 38.83% 0.46 1.161
97 39.27% 0.46 39.24% 0.45 1.142
98 39.68% 0.46 39.64% 0.45 1.100
99 40.08% 0.45 40.05% 0.45 1.097
100 40.49% 0.45 40.45% 0.44 1.089
101 40.89% 0.44 40.86% 0.44 1.084
102 41.30% 0.44 41.27% 0.43 1.075
103 41.70% 0.43 41.67% 0.43 1.060
104 42.11% 0.43 42.08% 0.42 1.054
105 42.51% 0.43 42.49% 0.42 1.052
106 42.91% 0.42 42.89% 0.42 1.047
107 43.32% 0.42 43.30% 0.41 1.041
108 43.72% 0.41 43.70% 0.41 1.036
109 44.13% 0.41 44.11% 0.40 1.028
110 44.53% 0.41 44.52% 0.40 1.028
111 44.94% 0.40 44.92% 0.40 1.028
112 45.34% 0.40 45.33% 0.39 1.003
113 45.75% 0.40 45.74% 0.39 0.998
114 46.15% 0.39 46.14% 0.39 0.992
115 46.56% 0.39 46.55% 0.38 0.991
116 46.96% 0.39 46.95% 0.38 0.990
117 47.37% 0.38 47.36% 0.38 0.977
118 47.77% 0.38 47.77% 0.37 0.962
119 48.18% 0.38 48.17% 0.37 0.957
120 48.58% 0.37 48.58% 0.37 0.931
121 48.99% 0.37 48.98% 0.36 0.926
122 49.39% 0.37 49.39% 0.36 0.924
123 49.80% 0.36 49.80% 0.36 0.920
124 50.20% 0.36 50.20% 0.36 0.918
125 50.61% 0.36 50.61% 0.35 0.914
126 51.01% 0.35 51.02% 0.35 0.886
127 51.42% 0.35 51.42% 0.35 0.886
128 51.82% 0.35 51.83% 0.34 0.882
129 52.23% 0.35 52.23% 0.34 0.875
130 52.63% 0.34 52.64% 0.34 0.862
131 53.04% 0.34 53.05% 0.34 0.862
132 53.44% 0.34 53.45% 0.33 0.852
133 53.85% 0.34 53.86% 0.33 0.840
134 54.25% 0.33 54.26% 0.33 0.839
135 54.66% 0.33 54.67% 0.33 0.836
136 55.06% 0.33 55.08% 0.32 0.829
137 55.47% 0.33 55.48% 0.32 0.816
138 55.87% 0.32 55.89% 0.32 0.810
139 56.28% 0.32 56.30% 0.32 0.805
140 56.68% 0.32 56.70% 0.31 0.804
141 57.09% 0.32 57.11% 0.31 0.804
142 57.49% 0.31 57.51% 0.31 0.801
143 57.89% 0.31 57.92% 0.31 0.794
144 58.30% 0.31 58.33% 0.31 0.785
145 58.70% 0.31 58.73% 0.30 0.772
146 59.11% 0.31 59.14% 0.30 0.761
147 59.51% 0.30 59.55% 0.30 0.755
148 59.92% 0.30 59.95% 0.30 0.747
149 60.32% 0.30 60.36% 0.30 0.713
150 60.73% 0.30 60.76% 0.29 0.713
151 61.13% 0.30 61.17% 0.29 0.710
152 61.54% 0.29 61.58% 0.29 0.708
153 61.94% 0.29 61.98% 0.29 0.706
154 62.35% 0.29 62.39% 0.29 0.705
155 62.75% 0.29 62.79% 0.28 0.703
156 63.16% 0.29 63.20% 0.28 0.693
157 63.56% 0.28 63.61% 0.28 0.675
158 63.97% 0.28 64.01% 0.28 0.672
159 64.37% 0.28 64.42% 0.28 0.666
160 64.78% 0.28 64.83% 0.28 0.662
161 65.18% 0.28 65.23% 0.27 0.640
162 65.59% 0.28 65.64% 0.27 0.630
163 65.99% 0.27 66.04% 0.27 0.620
164 66.40% 0.27 66.45% 0.27 0.617
165 66.80% 0.27 66.86% 0.27 0.614
166 67.21% 0.27 67.26% 0.27 0.613
167 67.61% 0.27 67.67% 0.26 0.584
168 68.02% 0.27 68.07% 0.26 0.581
169 68.42% 0.26 68.48% 0.26 0.580
170 68.83% 0.26 68.89% 0.26 0.575
171 69.23% 0.26 69.29% 0.26 0.575
172 69.64% 0.26 69.70% 0.26 0.573
173 70.04% 0.26 70.11% 0.25 0.571
174 70.45% 0.26 70.51% 0.25 0.569
175 70.85% 0.26 70.92% 0.25 0.562
176 71.26% 0.25 71.32% 0.25 0.549
177 71.66% 0.25 71.73% 0.25 0.534
178 72.06% 0.25 72.14% 0.25 0.531
179 72.47% 0.25 72.54% 0.25 0.528
180 72.87% 0.25 72.95% 0.24 0.527
181 73.28% 0.25 73.35% 0.24 0.527
182 73.68% 0.25 73.76% 0.24 0.523
183 74.09% 0.24 74.17% 0.24 0.521
184 74.49% 0.24 74.57% 0.24 0.515
185 74.90% 0.24 74.98% 0.24 0.507
186 75.30% 0.24 75.39% 0.24 0.503
187 75.71% 0.24 75.79% 0.24 0.502
188 76.11% 0.24 76.20% 0.23 0.497
189 76.52% 0.24 76.60% 0.23 0.493
190 76.92% 0.24 77.01% 0.23 0.492
191 77.33% 0.23 77.42% 0.23 0.479
192 77.73% 0.23 77.82% 0.23 0.464
193 78.14% 0.23 78.23% 0.23 0.460
194 78.54% 0.23 78.64% 0.23 0.434
195 78.95% 0.23 79.04% 0.23 0.433
196 79.35% 0.23 79.45% 0.22 0.429
197 79.76% 0.23 79.85% 0.22 0.411
198 80.16% 0.23 80.26% 0.22 0.405
199 80.57% 0.22 80.67% 0.22 0.398
200 80.97% 0.22 81.07% 0.22 0.396
201 81.38% 0.22 81.48% 0.22 0.392
202 81.78% 0.22 81.88% 0.22 0.390
203 82.19% 0.22 82.29% 0.22 0.387
204 82.59% 0.22 82.70% 0.22 0.384
205 83.00% 0.22 83.10% 0.21 0.383
206 83.40% 0.22 83.51% 0.21 0.374
207 83.81% 0.22 83.92% 0.21 0.374
208 84.21% 0.21 84.32% 0.21 0.371
209 84.62% 0.21 84.73% 0.21 0.361
210 85.02% 0.21 85.13% 0.21 0.358
211 85.43% 0.21 85.54% 0.21 0.356
212 85.83% 0.21 85.95% 0.21 0.355
213 86.23% 0.21 86.35% 0.21 0.353
214 86.64% 0.21 86.76% 0.21 0.349
215 87.04% 0.21 87.16% 0.20 0.347
216 87.45% 0.21 87.57% 0.20 0.346
217 87.85% 0.21 87.98% 0.20 0.339
218 88.26% 0.21 88.38% 0.20 0.295
219 88.66% 0.20 88.79% 0.20 0.295
220 89.07% 0.20 89.20% 0.20 0.284
221 89.47% 0.20 89.60% 0.20 0.280
222 89.88% 0.20 90.01% 0.20 0.266
223 90.28% 0.20 90.41% 0.20 0.261
224 90.69% 0.20 90.82% 0.20 0.259
225 91.09% 0.20 91.23% 0.20 0.258
226 91.50% 0.20 91.63% 0.19 0.251
227 91.90% 0.20 92.04% 0.19 0.246
228 92.31% 0.20 92.45% 0.19 0.246
229 92.71% 0.20 92.85% 0.19 0.244
230 93.12% 0.19 93.26% 0.19 0.241
231 93.52% 0.19 93.66% 0.19 0.236
232 93.93% 0.19 94.07% 0.19 0.234
233 94.33% 0.19 94.48% 0.19 0.227
234 94.74% 0.19 94.88% 0.19 0.223
235 95.14% 0.19 95.29% 0.19 0.219
236 95.55% 0.19 95.69% 0.19 0.218
237 95.95% 0.19 96.10% 0.19 0.210
238 96.36% 0.19 96.51% 0.18 0.208
239 96.76% 0.19 96.91% 0.18 0.204
240 97.17% 0.19 97.32% 0.18 0.200
241 97.57% 0.19 97.73% 0.18 0.197
242 97.98% 0.18 98.13% 0.18 0.192
243 98.38% 0.18 98.54% 0.18 0.185
244 98.79% 0.18 98.94% 0.18 0.185
245 99.19% 0.18 99.35% 0.18 0.183
246 99.60% 0.18 99.76% 0.18 0.183
POC #1: PEAK EVENTS - POST MITIGATED

WEIBULL (SWMM) CUNNANE
F = m/(nr+1) where F = frequency F = (i-0.4)/(n+0.2)
m = event rank i = rank
nr = total number of event n = sample size = # of storms n = number of year anlayzed
Number of Years Analyzed (n): 43.69
Total number of events (nr) 627
m or i F Return (yrs) F Return Q Q2 2.414
1 0.16% 44.69 0.10% 73.15 5.036 Q3 2.746
2 0.32% 22.35 0.26% 27.43 5.007 Q4 3.194
3 0.48% 14.90 0.41% 16.88 4.650 Q5 3.645
4 0.64% 11.17 0.57% 12.19 4.323 Q6 3.991
5 0.80% 8.94 0.73% 9.54 4.312 Q7 4.104
6 0.96% 7.45 0.89% 7.84 4.233 Q8 4.242
7 1.11% 6.38 1.05% 6.65 4.041 Q9 4.295
8 1.27% 5.59 1.21% 5.78 3.971 Q10 4.314
9 1.43% 4.97 1.37% 5.10 3.712
10 1.59% 4.47 1.53% 4.57 3.228
11 1.75% 4.06 1.69% 4.14 3.217
12 1.91% 3.72 1.85% 3.78 3.152
13 2.07% 3.44 2.01% 3.48 3.119
14 2.23% 3.19 2.17% 3.23 2.851
15 2.39% 2.98 2.33% 3.01 2.746
16 2.55% 2.79 2.49% 2.81 2.728
17 2.71% 2.63 2.65% 2.64 2.681
18 2.87% 2.48 2.81% 2.49 2.621
19 3.03% 2.35 2.97% 2.36 2.580
20 3.18% 2.23 3.13% 2.24 2.460
21 3.34% 2.13 3.28% 2.13 2.416
22 3.50% 2.03 3.44% 2.03 2.414
23 3.66% 1.94 3.60% 1.94 2.241
24 3.82% 1.86 3.76% 1.86 2.173
25 3.98% 1.79 3.92% 1.78 1.930
26 4.14% 1.72 4.08% 1.71 1.905
27 4.30% 1.66 4.24% 1.65 1.902
28 4.46% 1.60 4.40% 1.59 1.764
29 4.62% 1.54 4.56% 1.53 1.571
30 4.78% 1.49 4.72% 1.48 1.519
31 4.94% 1.44 4.88% 1.43 1.509
32 5.10% 1.40 5.04% 1.39 1.437
33 5.25% 1.35 5.20% 1.35 1.408
34 5.41% 1.31 5.36% 1.31 1.312
35 5.57% 1.28 5.52% 1.27 1.311
36 5.73% 1.24 5.68% 1.23 1.308
37 5.89% 1.21 5.84% 1.20 1.289
38 6.05% 1.18 5.99% 1.17 1.128
39 6.21% 1.15 6.15% 1.14 1.084
Weibull Cunnane PEAK EVENTS

SUMMARY OF
D:\75051 Barham Drive\13 Reports\In-house Prelim Reports\SWMM\BARHAM, POC 1 SUMMARY, 2020-0430 7/1/2020 71132.60 I I I

I I I I I
40 6.37% 1.12 6.31% 1.11 1.034
41 6.53% 1.09 6.47% 1.08 0.944
42 6.69% 1.06 6.63% 1.06 0.881
43 6.85% 1.04 6.79% 1.03 0.869
44 7.01% 1.02 6.95% 1.01 0.862
45 7.17% 0.99 7.11% 0.98 0.854
46 7.32% 0.97 7.27% 0.96 0.846
47 7.48% 0.95 7.43% 0.94 0.800
48 7.64% 0.93 7.59% 0.92 0.769
49 7.80% 0.91 7.75% 0.90 0.762
50 7.96% 0.89 7.91% 0.88 0.738
51 8.12% 0.88 8.07% 0.87 0.733
52 8.28% 0.86 8.23% 0.85 0.709
53 8.44% 0.84 8.39% 0.83 0.687
54 8.60% 0.83 8.55% 0.82 0.642
55 8.76% 0.81 8.71% 0.80 0.640
56 8.92% 0.80 8.86% 0.79 0.613
57 9.08% 0.78 9.02% 0.78 0.601
58 9.24% 0.77 9.18% 0.76 0.588
59 9.39% 0.76 9.34% 0.75 0.579
60 9.55% 0.74 9.50% 0.74 0.566
61 9.71% 0.73 9.66% 0.72 0.566
62 9.87% 0.72 9.82% 0.71 0.564
63 10.03% 0.71 9.98% 0.70 0.556
64 10.19% 0.70 10.14% 0.69 0.554
65 10.35% 0.69 10.30% 0.68 0.549
66 10.51% 0.68 10.46% 0.67 0.546
67 10.67% 0.67 10.62% 0.66 0.541
68 10.83% 0.66 10.78% 0.65 0.537
69 10.99% 0.65 10.94% 0.64 0.536
70 11.15% 0.64 11.10% 0.63 0.521
71 11.31% 0.63 11.26% 0.62 0.513
72 11.46% 0.62 11.42% 0.61 0.497
73 11.62% 0.61 11.58% 0.60 0.491
74 11.78% 0.60 11.73% 0.60 0.490
75 11.94% 0.60 11.89% 0.59 0.482
76 12.10% 0.59 12.05% 0.58 0.479
77 12.26% 0.58 12.21% 0.57 0.476
78 12.42% 0.57 12.37% 0.57 0.473
79 12.58% 0.57 12.53% 0.56 0.453
80 12.74% 0.56 12.69% 0.55 0.450
81 12.90% 0.55 12.85% 0.54 0.449
82 13.06% 0.55 13.01% 0.54 0.444
83 13.22% 0.54 13.17% 0.53 0.434
84 13.38% 0.53 13.33% 0.53 0.433
85 13.54% 0.53 13.49% 0.52 0.429
86 13.69% 0.52 13.65% 0.51 0.416
87 13.85% 0.51 13.81% 0.51 0.411
88 14.01% 0.51 13.97% 0.50 0.410
89 14.17% 0.50 14.13% 0.50 0.410
90 14.33% 0.50 14.29% 0.49 0.410
91 14.49% 0.49 14.45% 0.48 0.403
92 14.65% 0.49 14.60% 0.48 0.396
93 14.81% 0.48 14.76% 0.47 0.393
94 14.97% 0.48 14.92% 0.47 0.389
D:\75051 Barham Drive\13 Reports\In-house Prelim Reports\SWMM\BARHAM, POC 1 SUMMARY, 2020-0430 7/1/2020 71132.60 95 15.13% 0.47 15.08% 0.46 0.385
96 15.29% 0.47 15.24% 0.46 0.385
97 15.45% 0.46 15.40% 0.45 0.383
98 15.61% 0.46 15.56% 0.45 0.377
99 15.76% 0.45 15.72% 0.45 0.375
100 15.92% 0.45 15.88% 0.44 0.370
101 16.08% 0.44 16.04% 0.44 0.370
102 16.24% 0.44 16.20% 0.43 0.370
103 16.40% 0.43 16.36% 0.43 0.368
104 16.56% 0.43 16.52% 0.42 0.366
105 16.72% 0.43 16.68% 0.42 0.365
106 16.88% 0.42 16.84% 0.42 0.365
107 17.04% 0.42 17.00% 0.41 0.363
108 17.20% 0.41 17.16% 0.41 0.361
109 17.36% 0.41 17.32% 0.40 0.359
110 17.52% 0.41 17.47% 0.40 0.356
111 17.68% 0.40 17.63% 0.40 0.351
112 17.83% 0.40 17.79% 0.39 0.350
113 17.99% 0.40 17.95% 0.39 0.350
114 18.15% 0.39 18.11% 0.39 0.345
115 18.31% 0.39 18.27% 0.38 0.344
116 18.47% 0.39 18.43% 0.38 0.341
117 18.63% 0.38 18.59% 0.38 0.338
118 18.79% 0.38 18.75% 0.37 0.337
119 18.95% 0.38 18.91% 0.37 0.336
120 19.11% 0.37 19.07% 0.37 0.335
121 19.27% 0.37 19.23% 0.36 0.329
122 19.43% 0.37 19.39% 0.36 0.327
123 19.59% 0.36 19.55% 0.36 0.327
124 19.75% 0.36 19.71% 0.36 0.324
125 19.90% 0.36 19.87% 0.35 0.319
126 20.06% 0.35 20.03% 0.35 0.316
127 20.22% 0.35 20.18% 0.35 0.310
128 20.38% 0.35 20.34% 0.34 0.309
129 20.54% 0.35 20.50% 0.34 0.309
130 20.70% 0.34 20.66% 0.34 0.308
131 20.86% 0.34 20.82% 0.34 0.308
132 21.02% 0.34 20.98% 0.33 0.307
133 21.18% 0.34 21.14% 0.33 0.307
134 21.34% 0.33 21.30% 0.33 0.305
135 21.50% 0.33 21.46% 0.33 0.304
136 21.66% 0.33 21.62% 0.32 0.303
137 21.82% 0.33 21.78% 0.32 0.290
138 21.97% 0.32 21.94% 0.32 0.287
139 22.13% 0.32 22.10% 0.32 0.287
140 22.29% 0.32 22.26% 0.31 0.285
141 22.45% 0.32 22.42% 0.31 0.280
doubt #VALUE! #VALUE! #VALUE! #VALUE! 0.280
143 22.77% 0.31 22.74% 0.31 0.279
144 22.93% 0.31 22.90% 0.31 0.279
145 23.09% 0.31 23.05% 0.30 0.274
146 23.25% 0.31 23.21% 0.30 0.273
147 23.41% 0.30 23.37% 0.30 0.271
148 23.57% 0.30 23.53% 0.30 0.262
149 23.73% 0.30 23.69% 0.30 0.259
D:\75051 Barham Drive\13 Reports\In-house Prelim Reports\SWMM\BARHAM, POC 1 SUMMARY, 2020-0430 7/1/2020 71132.60 150 23.89% 0.30 23.85% 0.29 0.259
151 24.04% 0.30 24.01% 0.29 0.256
152 24.20% 0.29 24.17% 0.29 0.254
153 24.36% 0.29 24.33% 0.29 0.252
154 24.52% 0.29 24.49% 0.29 0.252
155 24.68% 0.29 24.65% 0.28 0.251
156 24.84% 0.29 24.81% 0.28 0.247
157 25.00% 0.28 24.97% 0.28 0.245
158 25.16% 0.28 25.13% 0.28 0.244
159 25.32% 0.28 25.29% 0.28 0.242
160 25.48% 0.28 25.45% 0.28 0.236
161 25.64% 0.28 25.61% 0.27 0.235
162 25.80% 0.28 25.77% 0.27 0.230
163 25.96% 0.27 25.92% 0.27 0.228
164 26.11% 0.27 26.08% 0.27 0.228
165 26.27% 0.27 26.24% 0.27 0.228
166 26.43% 0.27 26.40% 0.27 0.228
167 26.59% 0.27 26.56% 0.26 0.222
168 26.75% 0.27 26.72% 0.26 0.221
169 26.91% 0.26 26.88% 0.26 0.220
170 27.07% 0.26 27.04% 0.26 0.218
171 27.23% 0.26 27.20% 0.26 0.216
172 27.39% 0.26 27.36% 0.26 0.212
173 27.55% 0.26 27.52% 0.25 0.209
174 27.71% 0.26 27.68% 0.25 0.208
175 27.87% 0.26 27.84% 0.25 0.205
176 28.03% 0.25 28.00% 0.25 0.199
177 28.18% 0.25 28.16% 0.25 0.196
178 28.34% 0.25 28.32% 0.25 0.194
179 28.50% 0.25 28.48% 0.25 0.187
180 28.66% 0.25 28.64% 0.24 0.185
181 28.82% 0.25 28.79% 0.24 0.184
182 28.98% 0.25 28.95% 0.24 0.182
183 29.14% 0.24 29.11% 0.24 0.181
184 29.30% 0.24 29.27% 0.24 0.181
185 29.46% 0.24 29.43% 0.24 0.180
186 29.62% 0.24 29.59% 0.24 0.177
187 29.78% 0.24 29.75% 0.24 0.177
188 29.94% 0.24 29.91% 0.23 0.175
189 30.10% 0.24 30.07% 0.23 0.175
190 30.25% 0.24 30.23% 0.23 0.174
191 30.41% 0.23 30.39% 0.23 0.172
192 30.57% 0.23 30.55% 0.23 0.167
193 30.73% 0.23 30.71% 0.23 0.166
194 30.89% 0.23 30.87% 0.23 0.162
195 31.05% 0.23 31.03% 0.23 0.161
196 31.21% 0.23 31.19% 0.22 0.159
197 31.37% 0.23 31.35% 0.22 0.157
198 31.53% 0.23 31.51% 0.22 0.154
199 31.69% 0.22 31.66% 0.22 0.154
200 31.85% 0.22 31.82% 0.22 0.153
201 32.01% 0.22 31.98% 0.22 0.153
202 32.17% 0.22 32.14% 0.22 0.149
203 32.32% 0.22 32.30% 0.22 0.148
204 32.48% 0.22 32.46% 0.22 0.148
D:\75051 Barham Drive\13 Reports\In-house Prelim Reports\SWMM\BARHAM, POC 1 SUMMARY, 2020-0430 7/1/2020 71132.60 205 32.64% 0.22 32.62% 0.21 0.147
206 32.80% 0.22 32.78% 0.21 0.147
207 32.96% 0.22 32.94% 0.21 0.145
208 33.12% 0.21 33.10% 0.21 0.144
209 33.28% 0.21 33.26% 0.21 0.143
210 33.44% 0.21 33.42% 0.21 0.141
211 33.60% 0.21 33.58% 0.21 0.141
212 33.76% 0.21 33.74% 0.21 0.141
213 33.92% 0.21 33.90% 0.21 0.134
214 34.08% 0.21 34.06% 0.21 0.134
215 34.24% 0.21 34.22% 0.20 0.133
216 34.39% 0.21 34.38% 0.20 0.133
217 34.55% 0.21 34.53% 0.20 0.133
218 34.71% 0.21 34.69% 0.20 0.133
219 34.87% 0.20 34.85% 0.20 0.133
220 35.03% 0.20 35.01% 0.20 0.133
221 35.19% 0.20 35.17% 0.20 0.132
222 35.35% 0.20 35.33% 0.20 0.130
223 35.51% 0.20 35.49% 0.20 0.128
224 35.67% 0.20 35.65% 0.20 0.125
225 35.83% 0.20 35.81% 0.20 0.125
226 35.99% 0.20 35.97% 0.19 0.124
227 36.15% 0.20 36.13% 0.19 0.124
228 36.31% 0.20 36.29% 0.19 0.123
229 36.46% 0.20 36.45% 0.19 0.120
230 36.62% 0.19 36.61% 0.19 0.119
231 36.78% 0.19 36.77% 0.19 0.119
232 36.94% 0.19 36.93% 0.19 0.119
233 37.10% 0.19 37.09% 0.19 0.118
234 37.26% 0.19 37.24% 0.19 0.117
235 37.42% 0.19 37.40% 0.19 0.116
236 37.58% 0.19 37.56% 0.19 0.116
237 37.74% 0.19 37.72% 0.19 0.116
238 37.90% 0.19 37.88% 0.18 0.114
239 38.06% 0.19 38.04% 0.18 0.114
240 38.22% 0.19 38.20% 0.18 0.114
241 38.38% 0.19 38.36% 0.18 0.111
242 38.54% 0.18 38.52% 0.18 0.111
243 38.69% 0.18 38.68% 0.18 0.111
244 38.85% 0.18 38.84% 0.18 0.110
245 39.01% 0.18 39.00% 0.18 0.110
246 39.17% 0.18 39.16% 0.18 0.110
247 39.33% 0.18 39.32% 0.18 0.109
248 39.49% 0.18 39.48% 0.18 0.109
249 39.65% 0.18 39.64% 0.18 0.109
250 39.81% 0.18 39.80% 0.18 0.108
251 39.97% 0.18 39.96% 0.18 0.108
252 40.13% 0.18 40.11% 0.17 0.108
253 40.29% 0.18 40.27% 0.17 0.108
254 40.45% 0.18 40.43% 0.17 0.107
255 40.61% 0.18 40.59% 0.17 0.107
256 40.76% 0.17 40.75% 0.17 0.106
257 40.92% 0.17 40.91% 0.17 0.106
258 41.08% 0.17 41.07% 0.17 0.105
259 41.24% 0.17 41.23% 0.17 0.105
D:\75051 Barham Drive\13 Reports\In-house Prelim Reports\SWMM\BARHAM, POC 1 SUMMARY, 2020-0430 7/1/2020 71132.60 260 41.40% 0.17 41.39% 0.17 0.104
261 41.56% 0.17 41.55% 0.17 0.102
262 41.72% 0.17 41.71% 0.17 0.102
263 41.88% 0.17 41.87% 0.17 0.100
264 42.04% 0.17 42.03% 0.17 0.100
265 42.20% 0.17 42.19% 0.17 0.100
266 42.36% 0.17 42.35% 0.17 0.100
267 42.52% 0.17 42.51% 0.16 0.100
268 42.68% 0.17 42.67% 0.16 0.099
269 42.83% 0.17 42.83% 0.16 0.099
270 42.99% 0.17 42.98% 0.16 0.099
271 43.15% 0.16 43.14% 0.16 0.099
272 43.31% 0.16 43.30% 0.16 0.099
273 43.47% 0.16 43.46% 0.16 0.098
274 43.63% 0.16 43.62% 0.16 0.098
275 43.79% 0.16 43.78% 0.16 0.098
276 43.95% 0.16 43.94% 0.16 0.098
277 44.11% 0.16 44.10% 0.16 0.097
278 44.27% 0.16 44.26% 0.16 0.097
279 44.43% 0.16 44.42% 0.16 0.097
280 44.59% 0.16 44.58% 0.16 0.096
281 44.75% 0.16 44.74% 0.16 0.095
282 44.90% 0.16 44.90% 0.16 0.094
283 45.06% 0.16 45.06% 0.16 0.094
284 45.22% 0.16 45.22% 0.15 0.094
285 45.38% 0.16 45.38% 0.15 0.092
286 45.54% 0.16 45.54% 0.15 0.091
287 45.70% 0.16 45.70% 0.15 0.091
288 45.86% 0.16 45.85% 0.15 0.090
289 46.02% 0.15 46.01% 0.15 0.089
290 46.18% 0.15 46.17% 0.15 0.089
291 46.34% 0.15 46.33% 0.15 0.085
292 46.50% 0.15 46.49% 0.15 0.085
293 46.66% 0.15 46.65% 0.15 0.084
294 46.82% 0.15 46.81% 0.15 0.084
295 46.97% 0.15 46.97% 0.15 0.084
296 47.13% 0.15 47.13% 0.15 0.084
297 47.29% 0.15 47.29% 0.15 0.084
298 47.45% 0.15 47.45% 0.15 0.084
299 47.61% 0.15 47.61% 0.15 0.084
300 47.77% 0.15 47.77% 0.15 0.084
301 47.93% 0.15 47.93% 0.15 0.083
302 48.09% 0.15 48.09% 0.15 0.083
303 48.25% 0.15 48.25% 0.15 0.083
304 48.41% 0.15 48.41% 0.14 0.083
305 48.57% 0.15 48.57% 0.14 0.083
306 48.73% 0.15 48.72% 0.14 0.083
307 48.89% 0.15 48.88% 0.14 0.083
308 49.04% 0.15 49.04% 0.14 0.083
309 49.20% 0.14 49.20% 0.14 0.083
310 49.36% 0.14 49.36% 0.14 0.083
311 49.52% 0.14 49.52% 0.14 0.083
312 49.68% 0.14 49.68% 0.14 0.083
313 49.84% 0.14 49.84% 0.14 0.083
314 50.00% 0.14 50.00% 0.14 0.083
D:\75051 Barham Drive\13 Reports\In-house Prelim Reports\SWMM\BARHAM, POC 1 SUMMARY, 2020-0430 7/1/2020 71132.60 315 50.16% 0.14 50.16% 0.14 0.082
316 50.32% 0.14 50.32% 0.14 0.082
317 50.48% 0.14 50.48% 0.14 0.082
318 50.64% 0.14 50.64% 0.14 0.082
319 50.80% 0.14 50.80% 0.14 0.082
320 50.96% 0.14 50.96% 0.14 0.082
321 51.11% 0.14 51.12% 0.14 0.082
322 51.27% 0.14 51.28% 0.14 0.082
323 51.43% 0.14 51.43% 0.14 0.081
324 51.59% 0.14 51.59% 0.14 0.081
325 51.75% 0.14 51.75% 0.14 0.081
326 51.91% 0.14 51.91% 0.13 0.080
327 52.07% 0.14 52.07% 0.13 0.078
328 52.23% 0.14 52.23% 0.13 0.077
329 52.39% 0.14 52.39% 0.13 0.077
330 52.55% 0.14 52.55% 0.13 0.077
331 52.71% 0.14 52.71% 0.13 0.075
332 52.87% 0.13 52.87% 0.13 0.075
333 53.03% 0.13 53.03% 0.13 0.074
334 53.18% 0.13 53.19% 0.13 0.073
335 53.34% 0.13 53.35% 0.13 0.072
336 53.50% 0.13 53.51% 0.13 0.072
337 53.66% 0.13 53.67% 0.13 0.071
338 53.82% 0.13 53.83% 0.13 0.071
339 53.98% 0.13 53.99% 0.13 0.071
340 54.14% 0.13 54.15% 0.13 0.071
341 54.30% 0.13 54.30% 0.13 0.070
342 54.46% 0.13 54.46% 0.13 0.070
343 54.62% 0.13 54.62% 0.13 0.070
344 54.78% 0.13 54.78% 0.13 0.067
345 54.94% 0.13 54.94% 0.13 0.067
346 55.10% 0.13 55.10% 0.13 0.067
347 55.25% 0.13 55.26% 0.13 0.067
348 55.41% 0.13 55.42% 0.13 0.067
349 55.57% 0.13 55.58% 0.13 0.067
350 55.73% 0.13 55.74% 0.13 0.067
351 55.89% 0.13 55.90% 0.13 0.067
352 56.05% 0.13 56.06% 0.12 0.067
353 56.21% 0.13 56.22% 0.12 0.067
354 56.37% 0.13 56.38% 0.12 0.067
355 56.53% 0.13 56.54% 0.12 0.067
356 56.69% 0.13 56.70% 0.12 0.067
357 56.85% 0.13 56.86% 0.12 0.067
358 57.01% 0.12 57.02% 0.12 0.066
359 57.17% 0.12 57.17% 0.12 0.066
360 57.32% 0.12 57.33% 0.12 0.066
361 57.48% 0.12 57.49% 0.12 0.066
362 57.64% 0.12 57.65% 0.12 0.066
363 57.80% 0.12 57.81% 0.12 0.065
364 57.96% 0.12 57.97% 0.12 0.065
365 58.12% 0.12 58.13% 0.12 0.065
366 58.28% 0.12 58.29% 0.12 0.065
367 58.44% 0.12 58.45% 0.12 0.065
368 58.60% 0.12 58.61% 0.12 0.065
369 58.76% 0.12 58.77% 0.12 0.065
D:\75051 Barham Drive\13 Reports\In-house Prelim Reports\SWMM\BARHAM, POC 1 SUMMARY, 2020-0430 7/1/2020 71132.60 370 58.92% 0.12 58.93% 0.12 0.063
371 59.08% 0.12 59.09% 0.12 0.063
372 59.24% 0.12 59.25% 0.12 0.063
373 59.39% 0.12 59.41% 0.12 0.063
374 59.55% 0.12 59.57% 0.12 0.062
375 59.71% 0.12 59.73% 0.12 0.062
376 59.87% 0.12 59.89% 0.12 0.061
377 60.03% 0.12 60.04% 0.12 0.061
378 60.19% 0.12 60.20% 0.12 0.060
379 60.35% 0.12 60.36% 0.12 0.060
380 60.51% 0.12 60.52% 0.12 0.059
381 60.67% 0.12 60.68% 0.12 0.058
382 60.83% 0.12 60.84% 0.12 0.058
383 60.99% 0.12 61.00% 0.11 0.058
384 61.15% 0.12 61.16% 0.11 0.058
385 61.31% 0.12 61.32% 0.11 0.057
386 61.46% 0.12 61.48% 0.11 0.057
387 61.62% 0.12 61.64% 0.11 0.057
388 61.78% 0.12 61.80% 0.11 0.056
389 61.94% 0.11 61.96% 0.11 0.056
390 62.10% 0.11 62.12% 0.11 0.056
391 62.26% 0.11 62.28% 0.11 0.056
392 62.42% 0.11 62.44% 0.11 0.054
393 62.58% 0.11 62.60% 0.11 0.054
394 62.74% 0.11 62.76% 0.11 0.054
395 62.90% 0.11 62.91% 0.11 0.053
396 63.06% 0.11 63.07% 0.11 0.052
397 63.22% 0.11 63.23% 0.11 0.052
398 63.38% 0.11 63.39% 0.11 0.052
399 63.54% 0.11 63.55% 0.11 0.052
400 63.69% 0.11 63.71% 0.11 0.051
401 63.85% 0.11 63.87% 0.11 0.051
402 64.01% 0.11 64.03% 0.11 0.050
403 64.17% 0.11 64.19% 0.11 0.050
404 64.33% 0.11 64.35% 0.11 0.050
405 64.49% 0.11 64.51% 0.11 0.050
406 64.65% 0.11 64.67% 0.11 0.050
407 64.81% 0.11 64.83% 0.11 0.050
408 64.97% 0.11 64.99% 0.11 0.050
409 65.13% 0.11 65.15% 0.11 0.050
410 65.29% 0.11 65.31% 0.11 0.050
411 65.45% 0.11 65.47% 0.11 0.050
412 65.61% 0.11 65.63% 0.11 0.049
413 65.76% 0.11 65.78% 0.11 0.049
414 65.92% 0.11 65.94% 0.11 0.049
415 66.08% 0.11 66.10% 0.11 0.048
416 66.24% 0.11 66.26% 0.11 0.048
417 66.40% 0.11 66.42% 0.11 0.048
418 66.56% 0.11 66.58% 0.11 0.048
419 66.72% 0.11 66.74% 0.10 0.048
420 66.88% 0.11 66.90% 0.10 0.048
421 67.04% 0.11 67.06% 0.10 0.047
422 67.20% 0.11 67.22% 0.10 0.047
423 67.36% 0.11 67.38% 0.10 0.047
424 67.52% 0.11 67.54% 0.10 0.046
D:\75051 Barham Drive\13 Reports\In-house Prelim Reports\SWMM\BARHAM, POC 1 SUMMARY, 2020-0430 7/1/2020 71132.60 425 67.68% 0.11 67.70% 0.10 0.046
426 67.83% 0.10 67.86% 0.10 0.046
427 67.99% 0.10 68.02% 0.10 0.045
428 68.15% 0.10 68.18% 0.10 0.045
429 68.31% 0.10 68.34% 0.10 0.044
430 68.47% 0.10 68.49% 0.10 0.042
431 68.63% 0.10 68.65% 0.10 0.042
432 68.79% 0.10 68.81% 0.10 0.042
433 68.95% 0.10 68.97% 0.10 0.042
434 69.11% 0.10 69.13% 0.10 0.042
435 69.27% 0.10 69.29% 0.10 0.042
436 69.43% 0.10 69.45% 0.10 0.042
437 69.59% 0.10 69.61% 0.10 0.042
438 69.75% 0.10 69.77% 0.10 0.042
439 69.90% 0.10 69.93% 0.10 0.042
440 70.06% 0.10 70.09% 0.10 0.042
441 70.22% 0.10 70.25% 0.10 0.042
442 70.38% 0.10 70.41% 0.10 0.042
443 70.54% 0.10 70.57% 0.10 0.042
444 70.70% 0.10 70.73% 0.10 0.042
445 70.86% 0.10 70.89% 0.10 0.042
446 71.02% 0.10 71.05% 0.10 0.042
447 71.18% 0.10 71.21% 0.10 0.042
448 71.34% 0.10 71.36% 0.10 0.042
449 71.50% 0.10 71.52% 0.10 0.042
450 71.66% 0.10 71.68% 0.10 0.042
451 71.82% 0.10 71.84% 0.10 0.042
452 71.97% 0.10 72.00% 0.10 0.042
453 72.13% 0.10 72.16% 0.10 0.042
454 72.29% 0.10 72.32% 0.10 0.042
455 72.45% 0.10 72.48% 0.10 0.042
456 72.61% 0.10 72.64% 0.10 0.042
457 72.77% 0.10 72.80% 0.10 0.042
458 72.93% 0.10 72.96% 0.10 0.042
459 73.09% 0.10 73.12% 0.10 0.042
460 73.25% 0.10 73.28% 0.10 0.042
461 73.41% 0.10 73.44% 0.10 0.042
462 73.57% 0.10 73.60% 0.10 0.042
463 73.73% 0.10 73.76% 0.09 0.042
464 73.89% 0.10 73.92% 0.09 0.042
465 74.04% 0.10 74.08% 0.09 0.042
466 74.20% 0.10 74.23% 0.09 0.042
467 74.36% 0.10 74.39% 0.09 0.042
468 74.52% 0.10 74.55% 0.09 0.042
469 74.68% 0.10 74.71% 0.09 0.042
470 74.84% 0.10 74.87% 0.09 0.042
471 75.00% 0.09 75.03% 0.09 0.042
472 75.16% 0.09 75.19% 0.09 0.042
473 75.32% 0.09 75.35% 0.09 0.042
474 75.48% 0.09 75.51% 0.09 0.042
475 75.64% 0.09 75.67% 0.09 0.042
476 75.80% 0.09 75.83% 0.09 0.042
477 75.96% 0.09 75.99% 0.09 0.042
478 76.11% 0.09 76.15% 0.09 0.042
479 76.27% 0.09 76.31% 0.09 0.042
D:\75051 Barham Drive\13 Reports\In-house Prelim Reports\SWMM\BARHAM, POC 1 SUMMARY, 2020-0430 7/1/2020 71132.60 480 76.43% 0.09 76.47% 0.09 0.042
481 76.59% 0.09 76.63% 0.09 0.042
482 76.75% 0.09 76.79% 0.09 0.042
483 76.91% 0.09 76.95% 0.09 0.042
484 77.07% 0.09 77.10% 0.09 0.042
485 77.23% 0.09 77.26% 0.09 0.042
486 77.39% 0.09 77.42% 0.09 0.042
487 77.55% 0.09 77.58% 0.09 0.042
488 77.71% 0.09 77.74% 0.09 0.042
489 77.87% 0.09 77.90% 0.09 0.042
490 78.03% 0.09 78.06% 0.09 0.042
491 78.18% 0.09 78.22% 0.09 0.042
492 78.34% 0.09 78.38% 0.09 0.042
493 78.50% 0.09 78.54% 0.09 0.042
494 78.66% 0.09 78.70% 0.09 0.042
495 78.82% 0.09 78.86% 0.09 0.042
496 78.98% 0.09 79.02% 0.09 0.042
497 79.14% 0.09 79.18% 0.09 0.042
498 79.30% 0.09 79.34% 0.09 0.042
499 79.46% 0.09 79.50% 0.09 0.042
500 79.62% 0.09 79.66% 0.09 0.042
501 79.78% 0.09 79.82% 0.09 0.042
502 79.94% 0.09 79.97% 0.09 0.042
503 80.10% 0.09 80.13% 0.09 0.042
504 80.25% 0.09 80.29% 0.09 0.042
505 80.41% 0.09 80.45% 0.09 0.042
506 80.57% 0.09 80.61% 0.09 0.042
507 80.73% 0.09 80.77% 0.09 0.042
508 80.89% 0.09 80.93% 0.09 0.042
509 81.05% 0.09 81.09% 0.09 0.042
510 81.21% 0.09 81.25% 0.09 0.042
511 81.37% 0.09 81.41% 0.09 0.042
512 81.53% 0.09 81.57% 0.09 0.042
513 81.69% 0.09 81.73% 0.09 0.042
514 81.85% 0.09 81.89% 0.09 0.042
515 82.01% 0.09 82.05% 0.09 0.042
516 82.17% 0.09 82.21% 0.09 0.042
517 82.32% 0.09 82.37% 0.08 0.042
518 82.48% 0.09 82.53% 0.08 0.042
519 82.64% 0.09 82.68% 0.08 0.042
520 82.80% 0.09 82.84% 0.08 0.042
521 82.96% 0.09 83.00% 0.08 0.042
522 83.12% 0.09 83.16% 0.08 0.042
523 83.28% 0.09 83.32% 0.08 0.042
524 83.44% 0.09 83.48% 0.08 0.042
525 83.60% 0.09 83.64% 0.08 0.042
526 83.76% 0.08 83.80% 0.08 0.042
527 83.92% 0.08 83.96% 0.08 0.042
528 84.08% 0.08 84.12% 0.08 0.042
529 84.24% 0.08 84.28% 0.08 0.042
530 84.39% 0.08 84.44% 0.08 0.042
531 84.55% 0.08 84.60% 0.08 0.042
532 84.71% 0.08 84.76% 0.08 0.042
533 84.87% 0.08 84.92% 0.08 0.042
534 85.03% 0.08 85.08% 0.08 0.042
D:\75051 Barham Drive\13 Reports\In-house Prelim Reports\SWMM\BARHAM, POC 1 SUMMARY, 2020-0430 7/1/2020 71132.60 535 85.19% 0.08 85.24% 0.08 0.042
536 85.35% 0.08 85.40% 0.08 0.042
537 85.51% 0.08 85.55% 0.08 0.042
538 85.67% 0.08 85.71% 0.08 0.042
539 85.83% 0.08 85.87% 0.08 0.042
540 85.99% 0.08 86.03% 0.08 0.042
541 86.15% 0.08 86.19% 0.08 0.042
542 86.31% 0.08 86.35% 0.08 0.042
543 86.46% 0.08 86.51% 0.08 0.042
544 86.62% 0.08 86.67% 0.08 0.042
545 86.78% 0.08 86.83% 0.08 0.042
546 86.94% 0.08 86.99% 0.08 0.042
547 87.10% 0.08 87.15% 0.08 0.042
548 87.26% 0.08 87.31% 0.08 0.042
549 87.42% 0.08 87.47% 0.08 0.042
550 87.58% 0.08 87.63% 0.08 0.042
551 87.74% 0.08 87.79% 0.08 0.042
552 87.90% 0.08 87.95% 0.08 0.042
553 88.06% 0.08 88.11% 0.08 0.042
554 88.22% 0.08 88.27% 0.08 0.042
555 88.38% 0.08 88.42% 0.08 0.042
556 88.54% 0.08 88.58% 0.08 0.042
557 88.69% 0.08 88.74% 0.08 0.042
558 88.85% 0.08 88.90% 0.08 0.042
559 89.01% 0.08 89.06% 0.08 0.042
560 89.17% 0.08 89.22% 0.08 0.042
561 89.33% 0.08 89.38% 0.08 0.042
562 89.49% 0.08 89.54% 0.08 0.042
563 89.65% 0.08 89.70% 0.08 0.041
564 89.81% 0.08 89.86% 0.08 0.041
565 89.97% 0.08 90.02% 0.08 0.040
566 90.13% 0.08 90.18% 0.08 0.038
567 90.29% 0.08 90.34% 0.08 0.038
568 90.45% 0.08 90.50% 0.08 0.037
569 90.61% 0.08 90.66% 0.08 0.037
570 90.76% 0.08 90.82% 0.08 0.037
571 90.92% 0.08 90.98% 0.08 0.037
572 91.08% 0.08 91.14% 0.08 0.037
573 91.24% 0.08 91.29% 0.08 0.035
574 91.40% 0.08 91.45% 0.08 0.034
575 91.56% 0.08 91.61% 0.08 0.034
576 91.72% 0.08 91.77% 0.08 0.033
577 91.88% 0.08 91.93% 0.08 0.033
578 92.04% 0.08 92.09% 0.08 0.033
579 92.20% 0.08 92.25% 0.08 0.033
580 92.36% 0.08 92.41% 0.08 0.033
581 92.52% 0.08 92.57% 0.08 0.033
582 92.68% 0.08 92.73% 0.08 0.033
583 92.83% 0.08 92.89% 0.08 0.033
584 92.99% 0.08 93.05% 0.08 0.033
585 93.15% 0.08 93.21% 0.08 0.033
586 93.31% 0.08 93.37% 0.07 0.033
587 93.47% 0.08 93.53% 0.07 0.033
588 93.63% 0.08 93.69% 0.07 0.033
589 93.79% 0.08 93.85% 0.07 0.033
D:\75051 Barham Drive\13 Reports\In-house Prelim Reports\SWMM\BARHAM, POC 1 SUMMARY, 2020-0430 7/1/2020 71132.60 590 93.95% 0.08 94.01% 0.07 0.033
591 94.11% 0.08 94.16% 0.07 0.033
592 94.27% 0.08 94.32% 0.07 0.033
593 94.43% 0.08 94.48% 0.07 0.033
594 94.59% 0.08 94.64% 0.07 0.033
595 94.75% 0.08 94.80% 0.07 0.033
596 94.90% 0.07 94.96% 0.07 0.033
597 95.06% 0.07 95.12% 0.07 0.032
598 95.22% 0.07 95.28% 0.07 0.032
599 95.38% 0.07 95.44% 0.07 0.032
600 95.54% 0.07 95.60% 0.07 0.032
601 95.70% 0.07 95.76% 0.07 0.032
602 95.86% 0.07 95.92% 0.07 0.032
603 96.02% 0.07 96.08% 0.07 0.032
604 96.18% 0.07 96.24% 0.07 0.032
605 96.34% 0.07 96.40% 0.07 0.032
606 96.50% 0.07 96.56% 0.07 0.032
607 96.66% 0.07 96.72% 0.07 0.031
608 96.82% 0.07 96.88% 0.07 0.031
609 96.97% 0.07 97.03% 0.07 0.031
610 97.13% 0.07 97.19% 0.07 0.031
611 97.29% 0.07 97.35% 0.07 0.031
612 97.45% 0.07 97.51% 0.07 0.029
613 97.61% 0.07 97.67% 0.07 0.028
614 97.77% 0.07 97.83% 0.07 0.028
615 97.93% 0.07 97.99% 0.07 0.028
616 98.09% 0.07 98.15% 0.07 0.027
617 98.25% 0.07 98.31% 0.07 0.026
618 98.41% 0.07 98.47% 0.07 0.025
619 98.57% 0.07 98.63% 0.07 0.021
620 98.73% 0.07 98.79% 0.07 0.020
621 98.89% 0.07 98.95% 0.07 0.020
622 99.04% 0.07 99.11% 0.07 0.020
623 99.20% 0.07 99.27% 0.07 0.020
624 99.36% 0.07 99.43% 0.07 0.020
625 99.52% 0.07 99.59% 0.07 0.019
626 99.68% 0.07 99.74% 0.07 0.019
627 99.84% 0.07 99.90% 0.07 0.018
D:\75051 Barham Drive\13 Reports\In-house Prelim Reports\SWMM\BARHAM, POC 1 SUMMARY, 2020-0430 7/1/2020 71132.60

0.000

1.000

2.000

0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00

PEAK FLOW (CFS)

RETURN PERIOD (YEARS)
P .O.C. 1: FLOW FREQUENCY

POST-MIT

PRE-DEV

0.10Q2
Q10
-
I
-. -I -I -
I
-.

I -
I
I
•
I
I -
I ---. -
-~
I
'
I
I
.

I
I
I
'
.
' I
I
. •
I
~ I
'
I
•
' I
'
'
I
~
I
•
' I
~
' I
I
.

I
~ I -
"'
I
-I -, """'IL
--. '
-
-. -
~
---i---.. I
~ I
f t
I • ~ .
._

I I I I
~
"- . ....... I
...........
r - .._._
~

“943 BARHAM DRIVE” SB&O Inc.

S.W.M.M. ~ HMP CONTINUOUS SIMULATION (858) 560-1141

www.SBOINC.com

APPENDIX II: SUMMARY OF INPUT DATA/PARAMETERS

GENERAL OPTIONS & CLIMATOLOGY

Climatology Ed itor
Snow Melt
Temperature
Areal Depletion
Evapo ration
Adjustme nts
Wind Speed
Source of Evaporation Rates I Monthly Averages vi
Monthly Evaporation (in/ day)
Feb Mar

0.08 0.110
iii. Aug I Sep
I 0.2 0.16
Monthly Soil Recove,y
Patte rn (Optio nal)
Apr

0.16 I Oct

0.12 0 Evaporate Only During D,y Periods
May Jun

0.18 0.21
I Nov I Dec

0.08 0.06
~[_o_K~] ["can~ [ Help
X
Simulation Options X
General Dates Time Steps Dynamic Wave Files
Days Hr:Min:Sec
Reporting 1° ~I 101:00:00 ~I
Runoff:
1° ~I 101:00:00 ~I D,yWeather
Runoff:
1° ~I 101:00:00 ~I Wet Weather
Routing EJ Seconds
Steady Flow Periods
0 Skip Steady Flow Periods
System Flow Tolerance (%) o ~ ~
Lateral Flow Tolerance (%) o ~ ~
~-O_K_~I I Cancel I I Help

RAIN GAGES

Rain Gage ESCONDIDO.RES_STATION a
Property Value
Name ESCONDIDO.RES_STA TION i .

X-Coordinate 4725.275
Y-Coordinate 8538.462
'
Description
Tag
Rain Format INTENSllY
Time Interval 1:00
Snow Catch Factor 1.0
Data Source TIMESERIES
TIME SERIES:
- Series Name TS2
DATA FILE:
- File Name •
- Station ID •
- Rain Units IN
User-assigned name of rain gage

EXISTING CONDITION

File Edit View Project Report Tools Window Help
Ci ~ liiil ~ I ~ iMi ?{j ~ I \1' I ~ t::!::i ~ lTil L L I ~ % !!1 ~ ~ 0 ~ El. )J'. S 1 O ~ 0 'v ◊ 1:.:1 - C?@ ~ © T 1
Proj ect Map
..... Title/Notes
j .... Options
L. Climatology
v . Hydrology
i •. Rain Gages
Subcatchments
1 ... Aquifers
! .... Snow Packs
1 ... Unit Hydrographs
L.. LID Controls
. Hydraulics
. Quality
v. Curves
Control Curves
L. Diversion Curves
1 ... Pump Curves
j .... Rating Curves
L.. Shape Curves
L. Storage Curves
Tidal Curves
L. Time Series
Time Patterns
L.. Map Labels
ESCONDIDO.RES STATION
121 -
Bl
POC1
•

Subcatchmen t E-1
■ I Property Value I
Name E-1
! •
i I\ #
X-Coordinate 4644.309
Y-Coordinate 7337.398
Description PRE-DEV
Tag
Rain Gage E5CONDIDO.RES_STATION
Outlet POCl
Area 8.82
Width 415
%Slope 6
%1mperv 0
N-lmperv 0.012
N-Perv .15
Dstore-lmperv o.os
Dstore-Perv 0.10
%Zero-lmperv 25
Subarea Routing OUTLET
Percent Routed 100
Infiltration GREEN_AMPT ..,
User-assigned name of subcatchment
Infiltration Editor X
Infiltration M ethod GREEN_AMPT V
Property Value
Suction Head \9
Conductivity .025
Initial Deficit .3
Soil capillary suction head (inches or mm)
I OK I I Cancel I I Help I

Outfall POCl a
Property Value I
Name POCl
X-Coordinate 4670.330
Y-Coordinate 3780.220
Description
Tag
Inflows NO
Treatment NO
Invert El. 0
Tide Gate NO
Route To
Type FREE
Fixed Outfall I
Fixed Stage 0
Tidal Outfall I
Curve Name •
Time Series Outfall I
Series Name •
User-assigned name of outfall

Statistics Report Selection X
Object Category I Nod e vi
Object Name IPOCl Ell
Variable Analyzed I Total Inflow vi
Event Time Period I Event-Dependent vi
Statistic I Peak vi
Event Thresholds
Total Inflow 1,0176
Event Volume lo
Separation Time 124
OK Cancel I I Help
Time Series Plot Selection X
Time Periods
Start Date End Date
I 09/24/ 1964 vi I os12312oos vi
0 Elapsed Time @ Date/Time
Data Series
1 + Add 11 ~ Edit 11 - Delete I
Node POCl Total Inflow
...__o_K_....,I i Cancel I I Help

POST-DEVELOPMENT CONDITION

File Edit View Project Report Tools Window Help
' Ci ~ liiil ~ I ~ iMi ?{j ~ I \1' I ~ t::!::i ~ wiil 12 L I~ '2i .l ~ t:>- ~ 0 ~ El. )J'. S 1 9 ~ 0'v◊t:.:J-C?@te:t©T ,
Project Map
.... Title/Notes
1 .... Options
1 ... Climatology
> . Hydrology
> . Hydraulics
> . Quality
v Curves
.... Control Curves
.... Diversion Curves
.... Pump Curves
.... Rating Curves
.... Shape Curves
.... Storage Curves
.... Tidal Curves
... Time Series
Time Patterns
L.. Map Labels
Title/Notes
ESCONDIDO.RES STATION
121 -
~~
~~
3 S1
•
------ POC1 ,,_

Subcatchment P-1 a
I Property I value I
Name
I
I 1P-1
X·Coordinate 4939.560
Y-Coordinate 7175.825
O~cr iption POST-OEV
Tag
~ NDIDO.RES_STATION Rain Gage
Outlet BF-1
Area
E
Widt h
% Slope 3
% lmperv 80
N-lmperv
1Y=
N-Perv .15
Ostore-lmperv 0.05
Ostore-Perv 0.10
%Zero-lmpe_rv 25
Subarea Routing @unET
Percent Routed 100
Infiltration GREEN_AMPT
Groundwater NO
Snow Pack
LIO Controls
r
l and Uses 0
Initial Buildup NONE
Curb l ength Jo
User-assigned name of subcatchment
Infiltration Editor X
Infiltration M ethod GREEN_AMPT V
Property !Value
Suction Head \9
Conductivity 1,025
Initial Deficit l.3
Soil capillary suction head (inches or mm)
I OK I I Cancel I I Help I

Subcatchm ent BF-1 a
Property Value I
Name BF-1
X-Coord inate 6810.842
Y-Coord inate 7220.300
Description
Tag
Rain Gage ESCONDIDO.RES_STATION
Outlet Sl
Area .153
Width 140
% Slope 0
% 1mperv 0
N-lmperv 0.012
N-Perv 0.15
Dstore-lmperv 0.05
Dstore-Perv 0.10
%Zero-lmperv 25
Subarea Routing OUTLET
Percent Routed 100
Infiltration GREEN_AMPT ···I
Groundwater NO
Snow Pack
LID Control; 1
Land Uses 0
Initial Buildup NONE
Curb Length 0
Infiltration parameters (click to edit)

Subcatchm ent P-2 a
Property Value
Name P-2
X-Coord inate 2860.438
Y-Coord inate 5268.166
Description
Tag
Rain Gage ESCONDIDO.RES_STATION
Outlet POC1 '
Area 1.402
Width 360
% Slope 10
% 1mperv 30
N-lmperv 0.012
N-Perv .15
Dstore-lmperv 0.05
Dstore-Perv 0.10
%Zero-lmperv 25
Subarea Routing OUTLET
Percent Routed 100
Infiltration GREEN_AMPT ...

Groundwater NO
Snow Pack
LID Control; 0
Land Uses 0
Initial Buildup NONE
Curb Length 0
Infiltration parameters (click to edit)

Storage Unit 51 a
I Prop erty I value
l
Name S1
: X-Coord inate 16035.422
Y-Coord inate 5967.302
Description
~
Tag
Inflows NO
Treatment NO
Invert El. 0
Max. Depth 5.45
Initial Depth 0
Ponded Area 0
Evap. Facto r
Seepage Loss YES
Storage Cu,ve TABULAR
Functional Cu,ve
Coefficient 1000
Exponent 0
Constant 0
Tabular Cu,ve
Cu,ve Name BF
Storage Curve Editor X
Curve Name
Im
Description
~
Area " View ... I (ft2)
7191

5.45 13962
Load ...

Save ... 4
5 6
7 OK
8 9 Cancel
10 11 V Help

LID Control Editor X
Control Name: l'-'j:::ja=j ________ _, Surface Soil Storage Drain LID Type: I Bio-Retention Cell vi
Berm Height 16 (in. or mm)
Vegetation Volume 10.0
Fraction
Surfac e Roughn ess 10 (Manning; n)
Storage
Surface Slope 10 (percent)
D
•Optiona l
OK I I Cancel I I Help
LID Control Editor X
Contro l Nam e: IBF-3 Surface Soil Storage Drain
LID Type: I Bio-Retention Cell vi
Thickness
121 (in. or mm)
Poro sity 1,4 (volume fract ion)
Field Capacity 10.2 (volume fract ion)
Wilt ing Point 10.1 (volume fract ion) Storage
D
Conduct ivity
1s (in/ hr or mm/ hr)
Conduct ivity
1s Slope
•Optiona l Suction Head 11.s (in. or mm)
OK I I Cancel I I Help

LID Control Editor
Control Nam e: IBF-3
LID Type: I Bio-Retention Cell vi
Storage
D
•Optional
OK I I Cancel I I Help
LID Control Editor
Control Name: I._B_F_-3 ________ _,
LID Type: I Bio-Retention Cell
Storage
D
•Optional
OK I I Cancel I I Help
Surface Soil Storage Drain
Thickness 1, s
(in. or mm)
Void Ratio 1-6 (Voids / Solids)
Seepage Rate 1.02
(in/ hr or mm/ hr)
Clogging Factor 10
Surface Soil Storage Drain
Flow Coefficienr 1.07
Flow Exponent Llo_.s ___ _,
Offset Height 13
(in. or mm) '-----'
Drain Advisor
•Units are for flow in either in/ hr or
mm/ hr; use O if there is no drain.

X
X

Orifice 3 a
Property Value
Name 3
Inlet Node Sl
Outlet Node POC1
Description
'
Tag
'
Type SIDE
' Shape CIRCULAR
' Height .25 '
Width 0
Inlet Offset 3.25
Discharge Coeff. 0.65
Flap Gate NO
Time to Open/ Close 0
User-assigned name of orifice
Weir 1 ., a
Property Value
Name 1 I "'
Inlet Node Sl
Outlet Node POC1
Description ;
/
Tag /
/
/
Type TRANSVERSE /
/
/
Height .1 /
/
Length 20 '
Side Slope 0
Inlet Offset 3.95
Discharge Coeff. 3.33
Flap Gate NO
End Contractions 0
V
User-assigned name of weir

Outfall POCl a
Property Value
Name POCl
X-Coordinate 6185.286
Y-Coordinate 4209.809
Description
Tag
Inflow s NO
Treatment NO
Invert El. 0
Tide Gate NO
Route To
Type FREE
Fixed Outfall
Fixed Stage 0
Tidal Outfall
Curve Name •
Time Series Outfall
Series Name •
User-assigned name of outfall

Statistics Report Selection X
Object Category I Node vi
Object Name IPOCl Ell
Variable Analyzed I Total Inflow vi
Event Time Period I Event-Dependent vi
Statistic I Peak vi
Event Thresholds
Total Inflow 1,0176
Event Volume lo
Separation Time 124
OK Cancel I I Help
Time Series Plot Selection X
Time Periods
Start Date End Date
I 09/04/1963 vi I os12612ooa vi
0 Elapsed Time @ Date/Time
Data Series
1 + Add 11 ~ Edit 11 - Delete I
Node POCl Total Inflow
.,__o_K_..,I I Cancel I I Help

“943 BARHAM DRIVE” SB&O Inc.

S.W.M.M. ~ HMP CONTINUOUS SIMULATION (858) 560-1141

www.SBOINC.com

APPENDIX III: DRAIN COEFFICIENT CALCULATION SUMMARY

PA-12 APARTMENTS

SWMM MODEL - DRAIN ORIFICE CALULCATION SUMMARY
BASIN ID BF-1
DRAIN COEFF, C 0.07
T, DRAIN TIME (HRS) 72 HR
D, DEPTH (IN) 39 IN
cg 0.6
ALID 19863.4
D 2
g 32.2

City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020

ATTACHMENT 3
Structural BMP Maintenance Information

This is the cover sheet for Attachment 3.

Indicate which Items are Included behind this cover sheet:

Attachment
Sequence
Contents Checklist
Attachment 3a Structural BMP Maintenance Thresholds
and Actions (Required)

☒ Included

See Structural BMP Maintenance
Information Checklist on the back of
this Attachment cover sheet.

Attachment 3b Draft Maintenance Agreement (when
applicable)
Included
☒ Not Applicable for discretionary
phase.

City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020

Use this checklist to ensure the required information has been included in the Structural BMP Maintenance Information Attachment:

☒ Preliminary Design / Planning / CEQA level submittal:

Attachment 3a must identify:

☒ Typical maintenance indicators and actions for proposed structural BMP(s) based on Section 7.7 of the BMP Design Manual

Attachment 3b is not required for preliminary design / planning / CEQA level submittal.

Final Design level submittal:

Attachment 3a must identify:

Specific maintenance indicators and actions for proposed structural BMP(s). This shall be based on Section 7.7 of the BMP Design Manual and enhanced to reflect actual proposed components of the structural BMP(s)
How to access the structural BMP(s) to inspect and perform maintenance Features that are provided to facilitate inspection (e.g., observation ports, cleanouts, silt posts, or other features that allow the inspector to view necessary components of the structural BMP and compare to maintenance thresholds)
Manufacturer and part number for proprietary parts of structural BMP(s) when applicable
Maintenance thresholds specific to the structural BMP(s), with a location-specific frame of reference (e.g., level of accumulated materials that triggers removal of the materials, to be identified based on viewing marks on silt posts or measured with a survey rod with respect to a fixed benchmark within the BMP)
Recommended equipment to perform maintenance
When applicable, necessary special training or certification requirements for inspection and maintenance personnel such as confined space entry or hazardous waste management

Attachment 3b: For private entity operation and maintenance, Attachment 3b shall include a draft maintenance agreement in the local jurisdiction's s tandard format (PDP applicant to contact the [City Engineer] to obtain the current maintenance agreement forms).

BF-1
Biofiltration

BMP MAINTENANCE FACT SHEET
FOR
STRUCTURAL BMP BF-1 BIOFILTRATION

Biofiltration facilities are vegetated surface water systems that filter water through vegetation, and soil or engineered media prior to discharge via underdrain or overflow to the downstream conveyance system.

Biofiltration facilities have limited or no infiltration. T hey are typically designed to provide enough hydraulic head to move flows through the underdrain connection to the storm drain system . Typical biofiltration components include:

• Inflow distribution mechanisms (e.g., perimeter flow spreader or filter strips ) • Energy dissipation mechanism for concentrated inflows (e.g., splash blocks or riprap) • Shallow surface ponding for captured flows
• Side slope and basin bottom vegetation selected based on climate and ponding depth • Non-floating mulch layer
• Media layer (planting mix or engineered media) capable of supporting vegetation growth • Filter course layer consisting of aggregate to prevent the migration of fines into uncompacted native soils or the aggregate storage layer
• Aggregate storage layer with underdrain(s)
• Impermeable liner or uncompacted native soils at the bottom of the facility • Overflow structure

Normal Expected Maintenance

Biofiltration requires routine maintenance to : remove accumulated materials such as sediment, trash or debris ; maintain vegetation health ; maintain infiltration capacity of the media layer ; replenish mulch; and maintain integrity of side slopes, inlets, energy dissipators, and outlets . A summary table of standard inspection and maintenance indicators is provided within this Fact Sheet.

Non-Standard Maintenance or BMP Failure

If any of the following scenarios are observed, the BMP is not performing as intended to protect downstream waterways from pollution and/or erosion . C orrective maintenance, increased inspection and maintenance, BMP replacement, or a different BMP type will be required.

• The BMP is not drained between storm events. Surface ponding longer than approximately 24 hours following a storm event may be detrimental to vegetation hea lth, and surface ponding longer than approximately 96 hours following a storm event poses a risk of vector (mosquito) breeding. Poor drainage can result from clogging of the media layer, filter course, aggregate storage layer, underdrain, or outlet structure. The specific cause of the drainage issue must be determined and corrected . • Sediment, trash, or debris accumulation greater than 25% of the surface ponding volume within one month. This means the load from the tributary drainage area is too high, reduci ng BMP function or clogging the BMP . This would require pretreatment measures within the tributary area draining to the BMP to intercept the materials. Pretreatment components, especially for sediment, will extend the life of components that are more expensive to replace such as media, filter course, and aggregate layers. • Erosion due to concentrated storm water runoff flow that is not readily corrected by adding erosion control blankets, adding stone at flow entry points, or minor re -grading to restore prop er drainage according to the original plan. If the issue is not corrected by restoring the BMP to the original plan and grade, the [City Engineer] shall be contacted prior to any additional repairs or reconstruction.

BF-1 Page 1 of 11
January 12, 2017
BF-1
Biofiltration
Other Special Considerations

Biofiltration is a vegetated structural BMP. Vegetated structural BMPs that are constructed in the vicinity of, or connected to, an existing jurisdictional water or wetland could inadvertently result in creation of expanded waters or wetlands. As such, veg etated structural BMPs have the potential to come under the jurisdiction of the United States Army Corps of Engineers, SDRWQCB, California Department of Fish and Wildlife, or the United States Fish and Wildlife Service. This could result in the need for sp ecific resource agency permits and costly mitigation to perform maintenance of the structural BMP. Along with proper placement of a structural BMP, routine maintenance is key to preventing this scenario.

BF-1 Page 2 of 11
January 12, 2017
BF-1
Biofiltration

SUMMARY OF STANDARD INSPECTION AND MAINTENANCE FOR BF-1 BIOFILTRATION The property owner is responsible to ensure inspection, operation and maintenance of permanent BMPs on their property unless responsibility has been formally transferred to an agency, community facilities district, homeowners association, property owners association, or other special district.

Maintenance frequencies listed in this table are average/typical frequencies. Actual maintenance needs are site-specific, and maintenance may be required more frequently.

Maintenance must be performed whenever needed, based on maintenance indicators presented in this table. The BMP owner is responsible for conducting regular inspections to see when maintenance is needed based on the maintenance indicators. During the first year of operation of a structural BMP, inspection is recommended at least once prior to August 31 and then monthly from September through May. Inspection during a storm event is also recommended. After the initial period of frequent inspections, the minimum inspection and maintenance frequency can be determined based on the results of the first year inspections.

Threshold/Indicator Maintenance Action Typical Maintenance Frequency Accumulation of sediment, litter, or debris Remove and properly dispose of accumulated materials, without damage to the vegetation or compaction of the
media layer.
• Inspect monthly. If the BMP is 25% full* or more in
one month, increase inspection frequency to monthly
plus after every 0.1-inch or larger storm event.
• Remove any accumulated materials found at each
inspection.

Obstructed inlet or outlet structure Clear blockage. • Inspect monthly and after every 0.5 -inch or la rger storm event.
• Remove any accumulated materials found at each
inspection.

Damage to structural components such as weirs, inlet or outlet structures
Repair or replace as applicable • Inspect annually.
• Maintenance when needed.

Poor vegetation establishment Re-seed, re-plant, or re -establish vegetation per original plans.
• Inspect monthly.
• Maintenance when needed.

Dead or diseased vegetation Remove dead or diseased vegetation, re -seed, re-plant, or re-establish vegetation per original plans.
• Inspect monthly.
• Maintenance when needed.

Overgrown vegetation Mow or trim as appropriate. • Inspect monthly. • Maintenance when needed.
2/3 of mulch has decomposed, or mulch has been
removed
Remove decomposed fraction and top off with fresh
mulch to a total depth of 3 inches.
• Inspect monthly.
• Replenish mulch annually, or more frequently when
needed based on inspection.
*“25% full” is defined as ¼ of the depth from the design bottom elevation to the crest of the outflow structure (e.g., if the height to the outflow opening is 12 inches from the bottom elevation, then the materials must be removed when there is 3 inches of accumulation – this should be marked on the outflow structure).

BF-1 Page 3 of 11
January 12, 2017
BF-1
Biofiltration
SUMMARY OF STANDARD INSPECTION AND MAINTENANCE FOR BF-1 BIOFILTRATION (Continued from previous page) Threshold/Indicator Maintenance Action Typical Maintenance Frequency Erosion due to concentrated irrigation flow Repair/re-seed/re-plant eroded areas and adjust the irrigation system.
• Inspect monthly.
• Maintenance when needed.

Erosion due to concentrated storm water runoff flow Repair/re-seed/re-plant eroded areas, and make appropriate corrective measures such as adding erosion
control blankets, adding stone at flow entry points, or minor re -grading to restore proper drainage ac cording to the original plan. If the issue is not corrected by
restoring the BMP to the original plan and grade, the
[City Engineer] shall be contacted prior to any additional repairs or reconstruction.
• Inspect after every 0.5 -inch or larger storm event. I f erosion due to storm water flow has been observed,
increase inspection frequency to after every 0.1 -inch
or larger storm event.
• Maintenance when needed. If the issue is not
corrected by restoring the BMP to the original plan
and grade, the [City Engineer] shall be contacted prior to any additional repairs or reconstruction.

Standing water in BMP for longer than 24 hours
following a storm event
Surface ponding longer than approximately 24 hours
following a storm event may be detrimental to
vegetation health
Make appropriate corrective measures such as adjusting
irrigation system, removing obstructions of debris or
invasive vegetation, clearing underdrains, or
repairing/replacing clogged or compacted soils.
• Inspect monthly and after every 0.5 -inch o r larger
storm event. If standing water is observed, increase
inspection frequency to after every 0.1 -inch or larger storm event.
• Maintenance when needed.

Presence of mosquitos/larvae

For images of egg rafts, larva, pupa, and adult
mosquitos, see
http://www.mosquito.org/biology

If mosquitos/larvae are observed: first, immediately
remove any standing water by dispers ing to nearby
landscaping; second, make corrective measures as
applicable to restore BMP drainage to prevent standing water.

If mosquitos persist following corrective measures to
remove standing water, or if the BMP design does not
meet the 96 -hour drawdown criteria due to release
rates controlled by an orifice installed on the
underdrain, the [City Engineer] shall be contacted to
determine a solution. A different BMP type, or a Vector Management Plan prepared with concurrence from the
County of San Diego Department of Environmental
Health, may be required.
• Inspect monthly and after every 0.5 -inch or larger
storm event. If mosquitos are observed, increase
inspection frequency to after every 0.1 -inch or larger storm event.
• Maintenance when needed.

Underdrain clogged Clear blockage. • Inspect if standing water is observed for longer than 24-96 hours following a storm event.
• Maintenance when needed.

BF-1 Page 4 of 11
January 12, 2017
BF-1
Biofiltration
Date: Inspector: BMP ID No.:

Permit No.: APN(s):

Property / Development Name:

Responsible Party Name and Phone Number:

Property Address of BMP:

Responsible Party Address:

INSPECTION AND MAINTENANCE CHECKLIST FOR BF-1 BIOFILTRATION PAGE 1 of 5 Threshold/Indicator Maintenance Recommendation Date Description of Maintenance Conducted Accumulation of sediment, litter, or debris
Maintenance Needed?
☐ YES
☐ NO
☐ N/A

☐ Remove and properly dispose of
accumulated materials, without damage
to the vegetation
☐ If sediment, litter, or debris accumulation
exceeds 25% of the surface ponding
volume within one month (25% full*),
add a forebay or other pre-treatment
measures within the tributary area
draining to the BMP to intercept the
materials.
☐ Other / Comments:

Poor vegetation establishment
Maintenance Needed?
☐ YES
☐ NO
☐ N/A

☐ Re-seed, re-plant, or re-establish
vegetation per original plans
☐ Other / Comments:

*“25% full” is defined as ¼ of the depth from the design bottom elevation to the crest of the outflow structure (e.g., if the height to the outflow opening is 12 inches from the bottom elevation, then the materials must be removed when there is 3 inches of accumulation – this should be marked on the outflow structure).

BF-1 Page 7 of 11
January 12, 2017
BF-1
Biofiltration
Date: Inspector: BMP ID No.:

Permit No.: APN(s):

INSPECTION AND MAINTENANCE CHECKLIST FOR BF-1 BIOFILTRATION PAGE 2 of 5 Threshold/Indicator Maintenance Recommendation Date Description of Maintenance Conducted Dead or diseased vegetation
Maintenance Needed?
☐ YES
☐ NO
☐ N/A

☐ Remove dead or diseased vegetation, re-
seed, re-plant, or re-establish vegetation
per original plans
☐ Other / Comments:

Overgrown vegetation
Maintenance Needed?
☐ YES
☐ NO
☐ N/A

☐ Mow or trim as appropriate
☐ Other / Comments:

2/3 of mulch has decomposed, or mulch has
been removed
Maintenance Needed?
☐ YES
☐ NO
☐ N/A

☐ Remove decomposed fraction and top off
with fresh mulch to a total depth of 3
inches
☐ Other / Comments:

BF-1 Page 8 of 11
January 12, 2017
BF-1
Biofiltration
Date: Inspector: BMP ID No.:

Permit No.: APN(s):

INSPECTION AND MAINTENANCE CHECKLIST FOR BF-1 BIOFILTRATION PAGE 3 of 5 Threshold/Indicator Maintenance Recommendation Date Description of Maintenance Conducted Erosion due to concentrated irrigation flow
Maintenance Needed?
☐ YES
☐ NO
☐ N/A

☐ Repair/re-seed/re-plant eroded areas and
adjust the irrigation system
☐ Other / Comments:

Erosion due to concentrated storm water runoff
flow
Maintenance Needed?
☐ YES
☐ NO
☐ N/A

☐ Repair/re-seed/re-plant eroded areas,
and make appropriate corrective
measures such as adding erosion
control blankets, adding stone at flow
entry points, or minor re-grading to
restore proper drainage according to
the original plan
☐ If the issue is not corrected by restoring
the BMP to the original plan and grade,
the [City Engineer] shall be contacted
prior to any additional repairs or
reconstruction
☐ Other / Comments:

BF-1 Page 9 of 11
January 12, 2017
BF-1
Biofiltration
Date: Inspector: BMP ID No.:

Permit No.: APN(s):

INSPECTION AND MAINTENANCE CHECKLIST FOR BF-1 BIOFILTRATION PAGE 4 of 5 Threshold/Indicator Maintenance Recommendation Date Description of Maintenance Conducted Obstructed inlet or outlet structure
Maintenance Needed?
☐ YES
☐ NO
☐ N/A

☐ Clear blockage
☐ Other / Comments:

Underdrain clogged (inspect underdrain if
standing water is observed for longer than 24-96
hours following a storm event)
Maintenance Needed?
☐ YES
☐ NO
☐ N/A

☐ Clear blockage
☐ Other / Comments:

Damage to structural components such as weirs,
inlet or outlet structures
Maintenance Needed?
☐ YES
☐ NO
☐ N/A

☐ Repair or replace as applicable
☐ Other / Comments:

BF-1 Page 10 of 11
January 12, 2017
BF-1
Biofiltration
Date: Inspector: BMP ID No.:

Permit No.: APN(s):

INSPECTION AND MAINTENANCE CHECKLIST FOR BF-1 BIOFILTRATION PAGE 5 of 5 Threshold/Indicator Maintenance Recommendation Date Description of Maintenance Conducted Standing water in BMP for longer than 24 -96
hours following a storm event*
Surface ponding longer than approximately 24
hours following a storm event may be
detrimental to vegetation health
Maintenance Needed?
☐ YES
☐ NO
☐ N/A

☐ Make appropriate corrective measures
such as adjusting irrigation system,
removing obstructions of debris or
invasive vegetation, clearing
underdrains, or repairing/replacing
clogged or compacted soils
☐ Other / Comments:

Presence of mosquitos/larvae

For images of egg rafts, larva, pupa, and adult
mosquitos, see
http://www.mosquito.org/biology

Maintenance Needed?
☐ YES
☐ NO
☐ N/A

☐ Apply corrective measures to remove
standing water in BMP when standing
water occurs for longer than 24-96
hours following a storm event.**
☐ Other / Comments:

*Surface ponding longer than approximately 24 hours following a storm event may be detrimental to vegetation health, and surface ponding longer than approximately 96 hours following a storm event poses a risk of vector (mosquito) breeding. Poor drainage can result from clogging of the media layer , filter course, aggregate storage layer, underdrain, or outlet structure. The specific cause of the drainage issue must be determined and corrected. **If mosquitos persist following corrective measures to remove standing water, or if the BMP design does not meet the 96 -hour drawdown criteria due to release rates controlled by an orifice installed on the underdrain, the [City Engineer] shall be contacted to determine a solution. A different BMP type, or a Vector Management Plan prepared with concurrence from the County of San Diego Department of Environmental Health, may be required.

BF-1 Page 11 of 11
January 12, 2017
SD-1
Tree Wells

BMP MAINTENANCE FACT SHEET
FOR
SITE DESIGN BMP SD-1 TREE WELLS

Tree wells as site design BMPs are trees planted in configurations that allow storm water runoff to be directed into the soil immediately surrounding the tree . The tree may be contained within a planter box or structural cells. The surrounding area will be graded to direct runoff to the tree well. There may be features such as tree grates, suspended pavement design, or shall ow surface depressions designed to allow runoff into the tree well. Typical tree well components include:

• Trees of the appropriate species for site conditions and constraints • Available growing space based on tree species, soil type, water availability, su rrounding land uses, and project goals
• Entrance/opening that allows storm water runoff to flow into the tree well (e.g., a curb opening, tree grate, or surface depression)
• Optional suspended pavement design to provide structural support for adjacent paveme nt without requiring compaction of underlying layers
• Optional root barrier devices as needed; a root barrier is a device installed in the ground, between a tree and the sidewalk, intended to guide roots down and away from the sidewalk in order to prevent sidewalk lifting from tree roots
• Optional tree grates; to be considered to maximize available space for pedestrian circulation and to protect tree roots from compaction related to pedestrian circulation; tree grates are typically made up of porous material that will allow the runoff to soak through • Optional shallow surface depression for ponding of excess runoff • Optional planter box drain

Normal Expected Maintenance

Tree health shall be maintained as part of normal landscape maintenance. Additionally, ensure that storm water runoff can be conveyed into the tree well as designed. That is, the opening that allows storm water runoff to flow into the tree well (e.g., a curb opening, tree grate, or surface depression) shall not be blocked, fill ed, re-graded, or otherwise changed in a manner that prevents storm water from draining into the tree well. A summary table of standard inspection and maintenance indicators is provided within this Fact Sheet.

Non-Standard Maintenance or BMP Failure

Tree wells are site design BMPs that normally do not require maintenance actions beyond routine landscape maintenance. The normal expected maintenance described above ensures the BMP functionality. If changes have been made to the tree well entrance / opening such that runoff is prevented from draining into the tree well (e.g., a curb inlet opening is blocked by debris or a grate is clogged causing runoff to flow around instead of into the tree well, or a surface depression has been filled so runoff flows away from the tree well), the BMP is not performing as intended to protect downstream waterways from pollution and/or erosion . Corrective maintenance will be required to restore drainage into the tree well as designed.

Surface ponding of r unoff directed into tree wells is expected to infiltrate/evapotranspirate within 24- 96 hours following a storm event. Surface ponding longer than approximately 24 hours following a storm event may be detrimental to vegetation health, and surface ponding longer than approximat ely 96 hours following a storm event poses a risk of vector (mosquito) breeding. Poor drainage can result from clogging or compaction of the soils surrounding the tree. Loosen or replace the soils to restore drainage.

SD-1 Page 1 of 6
January 12, 2017
SD-1
Tree Wells
Other Special Considerations

Site design BMPs, such as tree wells , installed within a new development or redevelopment project are components of an overall storm water management strategy for the project. The presence of site design BMPs within a project is usually a factor in the determin ation of the amount of runoff to be managed with structural BMPs (i.e. , the amount of runoff expected to reach downstream retention or biofiltration basins that process storm water runoff from the project as a whole) . When site design BMPs are not maintained or are removed, this can lead to clogging or failure of downstream structural BMPs due to greater delivery of runoff and pollutants than intended for the structural BMP. Therefore, the [City Engineer] may require co nfirmation of maintenance of site design BMPs as part of their structural BMP maintenance documentation requirements. Site design BMPs that have been installed as part of the project should not be removed, nor should they be bypassed by re -routing roof drains or re-grading surfaces within the project. If changes are necessary, consult the [City Engineer] to determine requirements.

SD-1 Page 2 of 6
January 12, 2017
SD-1
Tree Wells

SUMMARY OF STANDARD INSPECTION AND MAINTENANCE FOR SD-1 TREE WELLS The property owner is responsible to ensure inspection, operation and maintenance of permanent BMPs on their property unless responsibility has been formally transferred to an agency, community facilities district, homeowners association, property owners association, or other special district.

Maintenance frequencies listed in this table are average/typical frequencies. Actual maintenance needs are site -specific, and maintenanc e may be required more frequently.

Maintenance must be performed whenever needed, based on maintenance indicators presented in this table. The BMP owner is responsible for conducting regular inspections to see when maintenance is needed based on the maintenance indicators. During the first year of operation of a structural BMP, inspection is recommended at least once prior to August 31 and then monthly from September through May. Inspection during a storm event is also recommended. After the init ial period of frequent inspections, the minimum inspection and maintenance frequency can be determined based on the results of the first year inspections.

Threshold/Indicator Maintenance Action Typical Maintenance Frequency Tree health Routine actions as necessary to maintain tree health. • Inspect monthly. • Maintenance when needed.

Dead or diseased tree Remove dead or diseased tree. Replace per original plans.
• Inspect monthly.
• Maintenance when needed.

Standing water in tree well for longer than 24 hours
following a storm event
Surface ponding longer than approximately 24 hours
following a storm event may be detrimental to tree
health
Loosen or replace soils surrounding the tree to restore drainage.
• Inspect monthly and after every 0.5 -inch or larger
storm event. If standing water is observed, increase
inspection frequency to after every 0.1 -inch or larger storm event.
• Maintenance when needed.

Presence of mosquitos/larvae

For images of egg rafts, larva, pupa, and adult
mosquitos, see
http://www.mosquito.org/biology

Disperse any standing water from the tree well to
nearby landscaping. Loosen or replace soils surrounding the tree to restore drainage (and prevent standing
water).
• Inspect mont hly and after every 0.5 -inch or larger
storm event. If mosquitos are observed, increase
inspection frequency to after every 0.1 -inch or larger storm event.
• Maintenance when needed
Entrance / opening to the tree well is blocked such that storm water will not drain into the tree well (e.g., a curb inlet opening is blocked by debris or a grate is clogged causing runoff to flow around instead of into the tree
well; or a surface depression is filled such that runoff drains away from the tree well)
Make repairs as appropriate to restore drainage into the tree well.
• Inspect monthly.
• Maintenance when needed.

SD-1 Page 3 of 6
January 12, 2017
SD-1
Tree Wells
References
American Mosquito Control Association.
http://www.mosquito.org/
County of San Diego. 2014. Low Impact Development Handbook. http://www.sandiegocounty.gov/content/sdc/dpw/watersheds/susmp/lid.html San Diego County Copermittees. 2016. Model BMP Design Manual, Appendix E, Fact Sheet SD-1. http://www.projectcleanwater.org/index.php?option=com_content&view=article&id=250&Itemid=220

SD-1 Page 4 of 6
January 12, 2017
SD-1
Tree Wells
Date: Inspector: BMP ID No.:

Permit No.: APN(s):

Property / Development Name:

Responsible Party Name and Phone Number:

Property Address of BMP:

Responsible Party Address:

INSPECTION AND MAINTENANCE CHECKLIST FOR SD-1 TREE WELLS PAGE 1 of 2 Threshold/Indicator Maintenance Recommendation Date Description of Maintenance Conducted Dead or diseased tree
Maintenance Needed?
☐ YES
☐ NO
☐ N/A

☐ Remove dead or diseased tree
☐ Replace per original plans
☐ Other / Comments:

☐ Loosen or replace soils surrounding the
tree to restore drainage
☐ Other / Comments:

SD-1 Page 5 of 6
January 12, 2017
SD-1
Tree Wells
Date: Inspector: BMP ID No.:

Permit No.: APN(s):

INSPECTION AND MAINTENANCE CHECKLIST FOR SD-1 TREE WELLS PAGE 2 of 2 Threshold/Indicator Maintenance Recommendation Date Description of Maintenance Conducted Presence of mosquitos/larvae

For images of egg rafts, larva, pupa, and adult
mosquitos, see
http://www.mosquito.org/biology
Maintenance Needed?
☐ YES
☐ NO
☐ N/A

☐ Disperse any standing water from the tree
well to nearby landscaping
☐ Loosen or replace soils surrounding the
tree to restore drainage (and prevent
standing water)
☐ Other / Comments:

Entrance / opening to the tree well is blocked
such that storm water will not drain into the
tree well (e.g., a curb inlet opening is blocked by
debris or a grate is clogged causing runoff to
flow around instead of into the tree well; or a
surface depression is filled such that runoff
drains away from the tree well)
Maintenance Needed?
☐ YES
☐ NO
☐ N/A

☐ Make repairs as appropriate to restore
drainage into the tree well
☐ Other / Comments:

SD-1 Page 6 of 6
January 12, 2017
City of San Marcos PDP SWQMP Template Date: March 15, 2016 PDP SWQMP Preparation Date: 19-June-2020

ATTACHMENT 4
Copy of Plan Sheets Showing Permanent Storm Water BMPs

This is the cover sheet for Attachment 4.

See DMA Exhibit

Use this checklist to ensure the required information has been included on the plans:

The plans must identify:

Structural BMP(s) with ID numbers matching Form I-6 Summary of PDP Structural BMPs The grading and drainage design shown on the plans must be consistent with the delineation of DMAs shown on the DMA exhibit
Details and specifications for construction of structural BMP(s) Signage indicating the location and boundary of structural BMP(s) as required by the [City Engineer] How to access the structural BMP(s) to inspect and perform maintenance Features that are provided to facilitate inspection (e.g., observation ports, cleanouts, silt posts, or other features that allow the inspector to view necessary components of the structural BMP and compare to maintenance thresholds)
Manufacturer and part number for proprietary parts of structural BMP(s) when applicable Maintenance thresholds specific to the structural BMP(s), with a location-specific frame of reference (e.g., level of accumulated materials that triggers removal of the materials, to be identified based on viewing marks on silt posts or measured with a survey rod with respect to a fixed benchmark within the BMP)
Recommended equipment to perform maintenance
When applicable, necessary special training or certification requirements for inspection and maintenance personnel such as confined space entry or hazardous waste management Include landscaping plan sheets showing vegetation requirements for vegetated structural BMP(s) All BMPs must be fully dimensioned on the plans
When proprietary BMPs are used, site-specific cross section with outflow, inflow, and model number shall be provided. Photocopies of general brochures are not acceptable.

San Marcos City CouncilMay 10, 2022

San Marcos City Council
May 10, 2022