Attachment 5n - PC Report H_HydroReports_Part-17 — Riverside City Council, May 20, 2025

PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices - 25 -

Appendix 7: Hydromodification
Supporting Detail Relating to Hydrologic Conditions of Concern

PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices Service Layer Credits: Sources: Esri, HERE,
DeLorme, TomTom, Intermap, increment P
Corp., GEBCO, USGS, FAO, NPS, NRCAN,
GeoBase, IGN, Kadaster NL, Ordnance
Survey, Esri Japan, METI, Esri China (Hong
Kong), swisstopo, MapmyIndia, ©
OpenStreetMap contributors, and the GIS
User Community
Map 1
Existing Storm Drain / Watercourse Delineation Map
SAR Permittees
Stream Channel Groups
Engineered, Fully Hardened, and Maintained (EFHM)
Engineered, Partially Hardened, and Maintained (EPHM)
Engineered, Earthen, and Maintained (EEM)
Not Engineered and Earthen (NEE)
Natural (NAT)
Santa Ana River/San Jacinto River
SAR Permit Boundary
County Boundary
±
0 5 102.5
Miles
Revised February 2017

RECEIVING OUTFALL CHANNEL (ENGINEERED,

FULLY HARDENED, AND MAINTAINED)

PROJECT SITE
SANTA ANA RIVER, REACH 2
PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices Service Layer Credits: Sources: Esri, HERE,
DeLorme, TomTom, Intermap, increment P
Corp., GEBCO, USGS, FAO, NPS, NRCAN,
GeoBase, IGN, Kadaster NL, Ordnance
Survey, Esri Japan, METI, Esri China (Hong
Kong), swisstopo, MapmyIndia, ©
OpenStreetMap contributors, and the GIS
User Community

RIVERSIDE

MENIFEE
CORONA
PERRIS
HEMET

MORENO VALLEY
JURUPA
VALLEY
LAKE

ELSINORE

BEAUMONT

BANNING

SAN JACINTO
NORCO

CALIMESA

EASTVALE

DESERT HOT SPRINGS
CANYON
LAKE
Map 2
HCOC Applicability Map
SAR Permittees
Legend
County Boundary
SAR Permit Boundary
Hydromodification Requirements
Mitigation Not Required
Mitigation May Be Required
Storm Drain / Watercourse Susceptibility Type
Not Susceptible
Potentially Susceptible
Santa Ana River
±
0 5 102.5
Miles
Updated February 2017

PROJECT SITE (DOES NOT FALL WITHIN APPLICABLE

AREA FOR HYDROMODIFIUCATION REQUIREMENTS)
PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices - 26 -

Appendix 8: Source Control
Pollutant Sources/Source Control Checklist
BMP Name
Check One
If not applicable, state
brief reason Included
Not
Applicable
Non-Structural Source Control BMPs
Education for Property Owners, Operators, Tenants,
Occupants, or Employees X
Activity Restrictions X
Irrigation System and Landscape Maintenance X
Common Area Litter Control X
Street Sweeping Private Streets and Parking Lots X
Drainage Facility Inspection and Maintenance X
Structural Source Control BMPs
MS4 Stenciling and Signage X
Landscape and Irrigation System Design X
Protect Slopes and Channels X
No significant slopes or
channels in development
area
Provide Community Car Wash Racks X Not present on-site Properly Design:

Fueling Areas X Not present on-site
Air/Water Supply Area Drainage X Not present on-site
Trash Storage Areas X
Loading Docks X Not present on-site
Maintenance Bays X Not present on-site
Vehicle and Equipment Wash Areas X Not present on-site Outdoor Material Storage Areas X Not present on-site
Outdoor Work Areas or Processing Areas X Not present on-site Provide Wash Water Controls for Food Preparation Areas X Not present on-site

MS4 stenciling and signage will be performed during construction and maintained annually by the owner. The landscape and irrigation system is efficient and drought tolerant. The owner will inspect the sprinkler system quarterly to verify that the sprinkler heads remain directed at landscape areas to limit runoff.

PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices Appendix 8

S T O R M W A T E R P O L L U T A N T S O U R C E S / S O U R C E C O N T R O L C H E C K L I S T 2014 SMR WQMP TEMPLATE Appendix 8 – Page 1 of 10

How to use this worksheet (also see instructions in Section G of the 2014 SMR WQMP Template):

1. Review Column 1 and identify which of these potential sources of stormwater pollutants apply to your site. Check each box that applies.

2. Review Column 2 and incorporate all of the corresponding applicable BMPs in your WQMP Exhibit.

3. Review Columns 3 and 4 and incorporate all of the corresponding applicable permanent controls and operational BMPs in your WQMP. Use the format shown in Table G.1on page 31 of this WQMP Template. Describe your specific BMPs in an accompanying narrative, and explain any special conditions or situations that required omitting BMPs or substituting alternative BMPs for those shown here.

IF THESE SOURCES WILL BE
ON THE PROJECT SITE …

 Include the following in lease
agreements: “Tenant shall not allow
anyone to discharge anything to storm
drains or to store or deposit materials
so as to create a potential discharge to
storm drains.”
 B. Interior floor drains
and elevator shaft sump
pumps
 State that interior floor drains and
elevator shaft sump pumps will be
plumbed to sanitary sewer.
 Inspect and maintain drains to prevent
blockages and overflow.
 C. Interior parking
garages
 State that parking garage floor
drains will be plumbed to the
sanitary sewer.
 Inspect and maintain drains to prevent
blockages and overflow.

X
X
X
X
X
X
X
X
X
X
PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices Appendix 8

S T O R M W A T E R P O L L U T A N T S O U R C E S / S O U R C E C O N T R O L C H E C K L I S T 2014 SMR WQMP TEMPLATE Appendix 8 – Page 2 of 10

IF THESE SOURCES WILL BE
ON THE PROJECT SITE …

 Preserve existing native trees,
shrubs, and ground cover to the
maximum extent possible.
 Design landscaping to minimize
irrigation and runoff, to promote
surface infiltration where
appropriate, and to minimize the
use of fertilizers and pesticides that
can contribute to stormwater
pollution.
 Where landscaped areas are used to
retain or detain stormwater, specify
plants that are tolerant of sa turated
soil conditions.
 Consider using pest-resistant plants,
especially adjacent to hardscape. To
insure successful establishment,
select plants appropriate to site soils,
slopes, climate, sun, wind, rain, land
use, air movement, ecological
consistency, and plant interactions.
 Maintain landscaping using minimum
or no pesticides.
 See applicable operational BMPs in
“What you should know
for…..Landscape and Gardening” at
http://www.rcflood.org/stormwater/Downlo
ads/LandscapeGardenBrochure.pdf

 Provide IPM information to new
owners, lessees and operators.

X
X
X
X
X
X
X
X
X
X
X
PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices Appendix 8

S T O R M W A T E R P O L L U T A N T S O U R C E S / S O U R C E C O N T R O L C H E C K L I S T 2014 SMR WQMP TEMPLATE Appendix 8 – Page 3 of 10

IF THESE SOURCES WILL BE
ON THE PROJECT SITE …

 F. Food service  For restaurants, grocery stores, and other food service operations, show
location (indoors or in a covered
area outdoors) of a floor sink or
other area for cleaning floor mats,
containers, and equipment.
 On the drawing, show a note that
this drain will be connected to a
grease interceptor before
discharging to the sanitary sewer.
 Describe the location and features
of the designated cleaning area.
 Describe the items to be cleaned in
this facility and how it has been
sized to insure that the largest
items can be accommodated.
 See the brochure, “The Food Service
Industry Best Management Practices
for: Restaurants, Grocery Stores,
Delicatessens and Bakeries” at
http://www.rcflood.org/stormwater/downloa
ds/FoodServ.pdf
Provide this brochure to new site
owners, lessees, and operators.
 G. Refuse areas  Show where site refuse and
recycled materials will be handled
and stored for pickup. See local
municipal requirements for sizes
and other details of refuse areas.
 If dumpsters or other receptacles
are outdoors, show how the
designated area will be covered,
graded, and paved to prevent run-
on and show locations of berms to
prevent runoff from the area.
 Any drains from dumpsters,
compactors, and tallow bin areas
shall be connected to a grease
removal device before discharge to
sanitary sewer.
 State how site refuse will be
handled and provide supporting
detail to what is shown on plans.
 State that sign s will be post ed on or
near dumpsters with the wo rds “Do
not dump hazardous materials
here” or similar.
 State how the following will be
implemented:

Provide adequate number of
receptacles. Inspect receptacles
regularly; repair or replace leaky
receptacles. Keep receptacles covered.

Prohibit/prevent dumping of liquid or
hazardous wastes. Post “no hazardous
materials” signs. Inspect and pick up
litter daily and clean up spills
immediately. Keep spill control
materials available on-site. See Fact
Sheet SC-34, “Waste Handling and
Disposal” in the CASQA Stormwater
Quality Handbooks at
www.cabmphandbooks.com

PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices Appendix 8

S T O R M W A T E R P O L L U T A N T S O U R C E S / S O U R C E C O N T R O L C H E C K L I S T 2014 SMR WQMP TEMPLATE Appendix 8 – Page 4 of 10

IF THESE SOURCES WILL BE
ON THE PROJECT SITE …

No processes to drain to exterior or
to storm drain system.”
 See Fact Sheet SC-10, “Non-
Stormwater Discharges” in the
CASQA Stormwater Quality
Handbooks at
www.cabmphandbooks.com

See the brochure “Industrial &
Commercial Facilities Best Management
Practices for: Industrial, Commercial
Facilities” at
http://www.rcflood.org/stormwater/Downloa
ds/IndustrialCommercialFacilities.pdf
 I. Outdoor storage of
equipment or materials.
(See rows J and K for
source control
measures for vehicle
cleaning, rep air, and
maintenance.)
 Show any outdoor storage areas,
including how materials will be
covered. Show how areas will be
graded and bermed to prevent run-
on or run-off from area.
 Storage of non-hazardous liquids
shall be covered by a roof and/or
drain to the sanitary sewer system,
and be contained by berms, dikes,
liners, or vaults.
 Storage of hazardous materials and
wastes must be in compliance with
the local hazardous materials
ordinance and a Hazardous
Materials Management Plan for the
site.
 Include a detailed description of
materials to be stored, storage
areas, and structural features to
prevent pollutants from entering
storm drains.

Where appropriate, reference
documentation of compliance with
the requirements of Hazardous
Materials Programs for:
 Hazardous Waste Generation
 Hazardous Materials Release
Response and Inventory
 California Accidental Release
(CalARP)
 Aboveground Storage Tank
 Uniform Fire Code Article 80
Section 103(b) & (c) 1991
 Underground Storage Tank
www.cchealth.org/groups/hazmat
/
 See the Fact Sheets SC-31, “Outdoor
Liquid Container Storage” and SC-33,
“Outdoor Storage of Raw Materials ”
in the CASQA Stormwater Quality
Handbooks at
www.cabmphandbooks.com

PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices Appendix 8

S T O R M W A T E R P O L L U T A N T S O U R C E S / S O U R C E C O N T R O L C H E C K L I S T 2014 SMR WQMP TEMPLATE Appendix 8 – Page 5 of 10

IF THESE SOURCES WILL BE
ON THE PROJECT SITE …

… THEN YOUR WQMP SHOULD INCLUDE THESE SOURCE CONTROL BM Ps, AS APPLICABLE 1 Potential Sources of
Runoff Pollutants
2 Permanent Controls—Show on
WQMP Drawings
3 Permanent Controls—List in WQMP
Table and Narrative
4 Operational BMPs—Include in WQMP
Table and Narrative
 J. Vehicle and
Equipment Cleaning
 Show on drawings as appropriate:
(1) Commercial/industrial facilities
having vehicle/equipment cleaning
needs shall either provide a
covered, bermed area for washing
activities or discourage
vehicle/equipment washing by
removing hose bibs and installing
signs prohibiting such uses.
(2) Multi-dwelling complexes shall
have a paved, bermed, and covered
car wash area (unless car washing
is prohibited on-site and hoses are
provided with an automatic shut-
off to discourage such use).
(3) Washing areas for cars, vehicles,
and equipment shall be paved,
designed to prevent run-on to or
runoff from the area, and plumbed
to drain to the sanitary sewer.
(4) Commercial car wash facilities
shall be designed such that no
runoff from the facility is
discharged to the storm drain
system. Wastewater from the
facility shall discharge to the
sanitary sewer, or a wastewater
reclamation system shall be
installed.
 If a car wash area is not provided,
describe any measures taken to
discourage on-site car washing and
explain how these will be enforced.

Describe operational measures to
implement the following (if
applicable):
 Washwater from vehicle and
equipment washing operations shall
not be discharged to the storm drain
system. Refer to “Outdoor Cleaning
Activities and Professional Mobile
Service Providers” for many of the
Potential Sources of Runoff Pollutants
categories below. Brochure can be
found at
http://www.rcflood.org/stormwater/downloads/
OutdoorCleaningActivities.pdf
 Car dealerships and similar may
rinse cars with water only.

PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices Appendix 8

S T O R M W A T E R P O L L U T A N T S O U R C E S / S O U R C E C O N T R O L C H E C K L I S T 2014 SMR WQMP TEMPLATE Appendix 8 – Page 6 of 10

IF THESE SOURCES WILL BE
ON THE PROJECT SITE …

… THEN YOUR WQMP SHOULD INCLUDE THESE SOURCE CONTROL BM Ps, AS APPLICABLE 1 Potential Sources of
Runoff Pollutants
2 Permanent Controls—Show on
WQMP Drawings
3 Permanent Controls—List in WQMP
Table and Narrative
4 Operational BMPs—Include in WQMP
Table and Narrative
 K. Vehicle/Equipment
Repair and
Maintenance
 Accommodate all vehicle
equipment repair and maintenance
indoors. Or designate an outdoor
work area and design the area to
prevent run-on and runoff of
stormwater.
 Show secondary containment for
exterior work areas where motor
oil, brake fluid, gasoline, diesel
fuel, radiator fluid, acid-containing
batteries or other hazardous
materials or hazardous wastes are
used or stored. Drains shall not be
installed within the secondary
containment areas.
 Add a note on the plans that states
either (1) there are no floor drains,
or (2) floor drains are connected to
wastewater pretreatment systems
prior to discharge to the sanitary
sewer and an industrial waste
discharge permit will be obtained.
 State that no vehicle repair or
maintenance will be done outdoors,
or else describe the required
features of the outdoor work area.
 State that there are no floor drains
or if there are floor drains, note the
agency from which an industrial
waste discharge permit will be
obtained and that the design meets
that agency’s requirements.
 State that there are no tanks,
containers or sinks to be used for
parts cleaning or rinsing or, if there
are, note the agency from which an
industrial waste discharge permit
will be obtained and that the
design meets that agency’s
requirements.

In the Stormwater Control Plan, note
that all of the following restrictions
apply to use the site:
 No person shall dispose of, nor permit
the disposal, directly or indirectly of
vehicle fluids, hazardous materials, or
rinsewater from parts cleaning into
storm drains.
 No vehicle fluid removal shall be
performed outside a building, nor on
asphalt or ground surfaces, whether
inside or outside a building, except in
such a manner as to ensure that any
spilled fluid will be in an area of
secondary containment. Leaking
vehicle fluids shall be contained or
drained from the vehicle immediately.
 No person shall leave unattended drip
parts or other open containers
containing vehicle fluid, unless such
containers are in use or in an area of
secondary containment.

Refer to “Automotive Maintenance &
Car Care Best Management Practices
for Auto Body Shops, Auto Repair
Shops, Car Dealerships, Gas Stations
and Fleet Service Operations”.

Brochure can be found at
http://rcflood.org/stormwater/
Refer to Outdoor Cleaning Activities
and Professional Mobile Service
Providers for many of the Potential
Sources of Runoff Pollutants
categories below. Brochure can be
found at http://rcflood.org/stormwater/
PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices Appendix 8

S T O R M W A T E R P O L L U T A N T S O U R C E S / S O U R C E C O N T R O L C H E C K L I S T 2014 SMR WQMP TEMPLATE Appendix 8 – Page 7 of 10

IF THESE SOURCES WILL BE
ON THE PROJECT SITE …

1.] The canopy [or
cover] shall not drain onto the
fueling area.
 The property owner shall dry sweep
the fueling area routinely.
 See the Fact Sheet SD-30 , “Fueling
Areas” in the CASQA Stormwater
Quality Handbooks at
www.cabmphandbooks.com

6 The fueling area shall be defined as the area extending a minimum of 6.5 feet from the corner of each fuel dispenser or the length at which the hose and nozzle assembly may be operated plus a minimum of one foot, whichever is greater.

PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices Appendix 8

S T O R M W A T E R P O L L U T A N T S O U R C E S / S O U R C E C O N T R O L C H E C K L I S T 2014 SMR WQMP TEMPLATE Appendix 8 – Page 8 of 10

IF THESE SOURCES WILL BE
ON THE PROJECT SITE …

… THEN YOUR WQMP SHOULD INCLUDE THESE SOURCE CONTROL BM Ps, AS APPLICABLE 1 Potential Sources of
Runoff Pollutants
2 Permanent Controls—Show on
WQMP Drawings
3 Permanent Controls—List in WQMP
Table and Narrative
4 Operational BMPs—Include in WQMP
Table and Narrative
 M. Loading Docks  Show a preliminary design for the
loading dock area, including
roofing and drainage. Loading
docks shall be covered and/or
graded to minimize run-on to and
runoff from the loading area. Roof
downspouts shall be positioned to
direct stormwater away from the
loading area. Water from loading
dock areas shall be drained to the
sanitary sewer, or diverted and
collected for ultimate discharge to
the sanitary sewer.
 Loading dock areas draining
directly to the sanitary sewer shall
be equipped with a spill control
valve or equivalent device, which
shall be kept closed during periods
of operation.
 Provide a roof overhang over the
loading area or install door skirts
(cowling) at each bay that enclose
the end of the trailer.
 Move loaded and unloaded items
indoors as soon as possible.
 See Fact Sheet SC-30, “Outdoor
Loading and Unloading,” in the
CASQA Stormwater Quality
Handbooks at
www.cabmphandbooks.com

PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices Appendix 8

S T O R M W A T E R P O L L U T A N T S O U R C E S / S O U R C E C O N T R O L C H E C K L I S T 2014 SMR WQMP TEMPLATE Appendix 8 – Page 9 of 10

IF THESE SOURCES WILL BE
ON THE PROJECT SITE …

 Condensate drain lines may
discharge to landscaped areas if the
flow is small enough that runoff will
not occur. Condensate drain lines
may not discharge to the storm
drain system.

 Rooftop equipment with potential
to produce pollutants shall be
roofed and/or have secondary
containment.

 Any drainage sumps on-site shall
feature a sediment sump to reduce
the quantity of sediment in pumped
water.

 Avoid roofing, gutters, and trim
made of copper or other
unprotected metals that may
leach into runoff.
 Include controls for other sources
as specified by local reviewer.

X
X
PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices Appendix 8

S T O R M W A T E R P O L L U T A N T S O U R C E S / S O U R C E C O N T R O L C H E C K L I S T 2014 SMR WQMP TEMPLATE Appendix 8 – Page 10 of 10

IF THESE SOURCES WILL BE
ON THE PROJECT SITE …

X
X
PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices - 27 -

Appendix 9: O&M
Operation and Maintenance Plan and Documentation of Finance, Maintenance and Recording Mechanisms The start-up date for maintenance activities will be at the close-out of construction.

HCA shall be responsible for maintenance:
4445 Magnolia Avenue
Riverside, CA 925001
Telephone: 951-788-3151

BMP Frequency Maintenance Activities
Catch Basin
Stenciling
Annually Inspect.

Drainage
System
Monthly Inspect catch basins for debris and clogging. Remove and dispose of contents as yard waste as necessary.

Litter Control Daily Empty trash receptacles and clean trash in plaza area.

Underground
Infiltration
Pipes

Quarterly

After Large
Storms (1”
or greater)

Inspect the top of the gravel layer. Remove lingering
sediments at the top of the gravel layer. Dispose contents as trash.

Inspect for stagnant ponding. If ponding is stagnant for more than 72 hours after the end of a storm event, test the unit infiltration rates once stagnant water is removed and replace the clogged portion of the underlying gravel. Replace areas with less than 0.5 inches per hour of hydraulic conductivity.

PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices January 2025 Page 1

WQMP
Operation & Maintenance (O&M) Plan

Project Name:

Riverside Community Hospital Garage
(Phase 1 Ultimate Buildout)
Southwest corner of Brockton Avenue and 14th Street
Riverside, CA 92501

Prepared for:

Zach Weidman
HCA/Riverside Community Hospital
4445 Magnolia Avenue
Riverside, CA 92501
(951) 788-3151

Prepared by:

Kimley-Horn and Associates
1100 W Town and Country Rd, Suite 700
Orange, CA 92868
(714) 939-1030

Prepared on:
01/14/2025

This O&M Plan describes the designated responsible party for implementation of this WQMP, including: operation and maintenance of all the structural BMP(s), conducting the training/educational program and duties, and any other necessary activities. The O&M Plan includes detailed inspection and maintenance requirements for all structural BMPs, including copies of any maintenance contract agreements, manufacturer’s maintenance requirements, permits, etc.

PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices January 2025 Page 2

9.1.1 Project Information

APN: 217-060-009, 217-060-020, 217-060-028, 217-060-027, 217-060-026, 217-060-024, 218-251-016
Address: Southwest corner of Brockton Avenue and 14th Street, Riverside, CA, 92501 Site Size: 3.28 ac
Proposed Structural BMPs: Infiltration CMP System (1), Pretreatment Unit (1), Storm Drain Inlets (19), Valley Gutter
Land use: Parking Garage
% Impervious of proposed site: 83%

Surface flow within each area drains towards inlets and is routed towards their respective BMPs. Overflows within the proposed systems connect into existing storm drain systems that lead to an existing 24” lateral along Tesquesquite Ave. Flow eventually drains into the Santa Ana River, Reach 3, continuing into Reach 2, Reach 1, and ultimately discharging into the Prado Basin Management Zone.

9.1.2 Responsible Party

The responsible party for implementation of this WQMP is:

HCA/Riverside Community Hospital
4445 Magnolia Avenue
Riverside, CA 92501

9.1.3 Record Keeping

Parties responsible for the O&M plan shall retain records for at least 5 years.

All training and educational activities and BMP operation and maintenance shall be documented to verify compliance with this O&M Plan. A sample Training Log and Inspection and Maintenance Log are included in Appendix 9.3 of this document.

The WQMP Verification Form (Appendix 9.4) shall be completed accurately and submitted, with associated documentation, to the City of Dana Point by September 30 of each year, or as requested by the City. Failure to complete and submit the verification form will result in a noncompliance and enforcement actions may be taken.

9.1.4 Electronic Data Submittal

This document along with the Site Plan and Attachments shall be provided in PDF format.

Autocad files and/or GIS coordinates of BMPs shall also be submitted to the City.

9.1.5 Vector Control

Standing water which exists for longer than 72 hours may contribute to mosquito breeding areas.

Best Management Practices (BMPs) shall be inspected for standing water on a regular basis.

PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices January 2025 Page 3

Standing water may indicate that the BMP is not functioning properly and proper action to remedy the situation shall be taken in a timely manner.

Elimination of standing water and managing garbage, lawn clippings, and pet droppings, can help decrease the presence of mosquitoes and flies in the area.

The Riverside County Flood Control District may be contacted for more information and support at 951-955-1200.

Required Permits

Permits are not required for the implementation, operation, and maintenance of the BMPs.

9.1.6 Inspections

The City may conduct a site inspection to evaluate compliance with the Project WQMP, at any time, in accordance with Dana Point Municipal Code Chapter 15.10, Storm Water/Surface Runoff Water Quality.

9.1.7 Monitoring Plan

The City or other agencies may require a monitoring plan. Details regarding monitoring plan, such as parameters to be tested, frequency, testing locations, laboratory, etc. shall be included as appropriate.

A monitoring plan is not required for the project.

9.1.8 Operation and Maintenance Requirements

The Table below addresses each BMP included in this project that requires regular implementation and/or operation & maintenance.

PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices January 2025 Page 4

BMP Implementation, Inspection and
Maintenance Requirements
Frequency
N1. Education for Property
Owners, Tenants and Occupants
RP will insure that all owners & tenants will be
given a copy of the recorded CC&R’s which will
contain a section outlining the environmental
awareness education materials at the close of
escrow.

RP shall distribute appropriate materials to owners,
tenants and/or occupants via contract language,
mailings, website or meeting.

Information to be initially
provided to owners &
tenants upon sale or lease
agreement.

Educational materials will
be provided to owners
and/or tenants annually,
thereafter.

Brochures can be requested or downloaded from
www.ocwatersheds.com.

Brochures and educational articles for RP
distribution can also be requested from City Water
Quality Engineer.

N2. Activity Restriction Within the CC&R’s or lease agreement, the following activity restrictions shall be enforced:

Continuous
N3. Common Area Landscape
Management & Efficient
Landscape Design
Landscape Management Includes:
• Mitigation of the potential dangers of fertilizer
and pesticide usage through the incorporation
of an Integrated Pest Management Program
(IPM).
• Monitor for runoff and efficiency regularly.
• Implementation of a water budget.
• Irrigation systems shall be automatically
controlled and designed, installed, and
maintained so as to minimize overspray and
runoff onto streets, sidewalks, driveways,
structures, windows, walls, and fences.
• Use of native and drought tolerant species
when replanting
Inspected once a wee k
N11. Common Area Litter Control Weekly sweeping and trash pickup as necessary within all project areas and common landscape
areas. Daily inspection of trash receptacles to
ensure that lids are closed and pick up any excess
trash on the ground, noting trash disposal
violations by homeowners and reporting the
violations to the HOA/RP for investigation.

Daily inspection and
weekly sweeping and
clean-up or as needed
N12. Contractor/Employee Training All contractors shall be trained and made aware of this WQMP and operation and maintenance
requirements of BMPs.

At first hire and annually
thereafter for HOA
personnel and employees,
to include the educational
materials contained in the
approved Water Quality
Management Plan.

PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices January 2025 Page 5

BMP Implementation, Inspection and
Maintenance Requirements
Frequency
N14. Common Area Catch Basin
Inspection
Catch basins will be owned, inspected and
maintained by the HOA/RP. Catch basins will be
inspected at a minimum on a yearly basis, and
prior to the storm season, no later than October 1st
of each year.

At a minimum, basins will
be inspected and cleaned
around October 1ST of
each year, prior to “first
flush” storm, or as
necessary after large
storm events to clear inlets
of trash, debris and silt.

N15. Street Sweeping Private
Streets and Parking Lots
Vacuum street sweeping will occur on a weekly
basis.

Streets will be vacuum
swept on a weekly basis.

SD-13 Provide Storm Drain System
Stenciling and Signage
All catch basins where applicable in paved areas,
will be marked or stenciled with “No Dumping -
Drains to Ocean, No Descargue Basura” language.

This will be done in a location that can be clearly
seen by all and will be routinely inspected and re-
labeled, as necessary. Thereafter, the
owner/operator shall routinely inspect and re-label
the catch basins, as necessary.

Catch basin labels will be
inspected once annually
and relabeled as
necessary to maintain
legibility.

SD-32 Design and Construct Trash
and Waste Storage Areas to
Reduce Pollutant Introduction
Trash will be removed by the local private solid
waste management contractor on a weekly basis
for proper disposal of the trash to landfill; with
recyclable materials and greenwastes to be
processed offsite.

Trash dumpster shall be
kept in a non-leaking
condition.

PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices January 2025 Page 6

BMP Implementation, Inspection and
Maintenance Requirements
Frequency
LID BMP # 1:

Contech CMP Infiltration System
Per manufacturer’s recommendations,
inspections should be performed annually at
a minimum, where more frequent inspections
may be required due to instances in which
one would expect higher sediment
accumulation. Record of inspection is to be
maintained for the life of the system.

Maintenance of CMP system shall be
performed when inspections reveal
accumulated sediment or trash clogging the
discharge orifice. It is recommended that
systems are designed with an
access/inspection manhole situated at or
near the inlet and outlet orifice.

For more details, see the refer to the CDS
Inspection and Maintenance Guide attached
in Appendix 9.3.

As recommended.

LID BMP # 2:

Pretreatment Unit
Per manufacturer’s recommendations,
inspections should be performed twice per
year at a minimum, where more frequent
inspections may be required due to
occurrences such as sanding operations or
equipment washdown. Visual inspection shall
ascertain that system is in working order and
that there are no blockages or obstructions
within the inlet and separation screen.

Maintenance of system shall be performed
during dry weather conditions when no flow is
entering the system. It is recommended to use a
vacuum truck as the most effective and
convenient approach. Remove the associated
manhole cover and and drain the sediment using
the vacuum hose.

For more details, see the refer to the
Inspection and Maintenance Guide attached in
Appendix 9.3.

As recommended.

PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices January 2025 Page 7

Appendix 9.1

BMP SITE PLAN

TO BE PROVIDED IN FINAL SUBMITTAL
PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices January 2025 Page 8

Appendix 9.2

EDUCATIONAL MATERIALS
The following is a selection of Educational Materials for Homeowners, Contractors and employees that address BMPS and water quality issues. Many are available in English and Spanish.

To meet the educational requirements of this O&M Plan, educational brochures can be downloaded or requested at no charge at https://rcwatershed.org/about/links -and-resources/outreach -materials -library/ for inclusion on a website, in a newsletter or mailed to property owners, tenants and/or contractors. Property owners, tenants, staff and/or contractors must receive education/training at least once per year.

Brochure Pollutant(s) Addressed Activities Addressed
Household hazardous Household maintenance and
"The Ocean Begins At Your Front
Door" – English, Spanish,
Vietnamese
waste, trash, motor oil,
chlorine, overwatering,
green waste, dirt,
pesticides/fertilizer, pet
activities (i.e. hosing driveway),
automotive maintenance and
washing, pool maintenance,
landscape and gardening, trash
waste disposal, pet care
Homeowners Guide for Household hazardous Preventing urban runoff through Sustainable Water Use Pamphlet waste, trash, motor oil, low impact development in chlorine, overwatering, residential properties, water
green waste, dirt, conservation, use of IPM
pesticides/fertilizer, pet techniques and California-friendly waste landscaping, general water
pollution prevention methods
"Help Prevent Ocean Pollution: Motor Oil Automotive Maintenance, Your Local Used Oil Collection Disposal of Used Motor Oil Center" - South– English, Spanish,
Vietnamese
“Help Prevent Ocean Pollution:

Tips for Pool Maintenance” –
English, Spanish
Chlorine, runoff Pool Drainage/Maintenance
“Help Prevent Ocean Pollution: Fertilizer, pesticide, dirt, overwatering, green
waste
Landscape maintenance,
pesticide/fertilizer application,
proper disposal of household
hazardous waste and green waste
Tips for Landscape and
Gardening” – English, Spanish
“Help Prevent Ocean Pollution:

Tips for Pet Care” – English,
Spanish
Surfactants, chemicals,
pet waste
Proper disposal of pet waste,
proper pet bathing techniques
Household hazardous Household maintenance and
“Help Prevent Ocean Pollution:

Household Tips” – English,
Spanish
waste, pet waste,
pesticides/fertilizers,
overwatering, green
waste, surfactants, motor
activities (i.e. hosing driveway),
automotive maintenance and
washing, pool maintenance,
landscape and gardening, trash
oil, trash disposal, pet care
“Help Prevent Ocean Pollution: Household hazardous Proper identification and disposal Proper Disposal of Household wastes of household hazardous wastes Hazardous Materials” – English,
Spanish, Vietnamese
PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices January 2025 Page 9

Brochure Pollutant(s) Addressed Activities Addressed
“Help Prevent Ocean Pollution:

Maintenance Practices for Your
Business” – English, Spanish
Fertilizer, pesticides,
green waste,
overwatering, trash,
toxic substances
Landscape maintenance, proper
application of pesticides and
fertilizers, trash management,
proper storage of materials
“Help Prevent Ocean Pollution:

Tips for Using Concrete and
Mortar” – English, Spanish
Concrete and mortar,
slurry
Proper preparation, use, clean up
and disposal of concrete and
mortar

“Responsible Pest Control”
Pesticides Proper identification of pests,
selection of least toxic chemical,
proper pesticide application, spill
prevention and proper storage and
disposal of pesticides (use of
Integrated Pest Management
(IPM) techniques)
Chlorine, chemicals, pet Pool maintenance, spill
“Help Prevent Ocean Pollution:

Residential Pool, Landscape and
Hardscape Drains” – English,
Spanish
waste, green waste,
overwatering, motor oil
and vehicle fluids
prevention, proper disposal of
household hazardous waste,
proper disposal of pet waste,
proper use of pesticides and
fertilizers, proper vehicle
maintenance
“Help Prevent Ocean Pollution:

Proper Use and Disposal of
Paint” – English, Spanish
Paint, chemicals Proper use, storage and disposal of
paint
Construction debris, Proper storage of construction
“Help Prevent Ocean Pollution: concrete, paint, materials, recycling of construction Tips for Home Improvement household hazardous materials, proper disposal of Projects” – English, Spanish waste, sediment household hazardous waste, proper erosion and spill control
“Help Prevent Ocean Pollution:

Children’s Coloring & Activity
Book”
Trash, pet waste, motor
oil, green waste
Litter control, proper disposal of
pet waste, proper spill clean up
(e.g. use of cat litter)
“Help Prevent Ocean Pollution:

Tips for the Automotive
Industry” – English, Spanish
Motor oil, metals,
surfactants, toxic
substances, dirt
Proper maintenance and washing
practices for automobiles, proper
storage and disposal of
automotive liquids and materials
Motor oil, metals, Proper maintenance and washing
surfactants, toxic practices for automobiles and
“Help Prevent Ocean Pollution: substances automotive detailing materials, Tips for the Home Mechanic” proper storage and disposal of automotive liquids and materials,
use of used oil collection centers
“Compliance Best Management Surfactants, toxic Mobile car washing and detailing, Practices for Mobile Businesses” substances, dirt, metals proper high pressure cleaning, proper storage and disposal of
washwater from mobile
automotive detailing, washing and
carpet and fabric cleaning
PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices January 2025 Page 10

Brochure Pollutant(s) Addressed Activities Addressed
“Help Prevent Ocean Pollution: A Grease, food waste, trash Proper food waste disposal, Guide for Food Service Facilities” proper grease and oil disposal, – English, Spanish, Vietnamese proper procedures for spill cleanup, proper maintenance of
trash dumpsters, proper floor mat
cleaning, proper wastewater
disposal

Regulatory Information

1. City of Riverside Municipal Code: Storm Water/Surface Runoff Water Quality

2. City of Riverside Municipal Code: Landscaping Standards and Requirements

Both of the above Code Chapters are available on the City’s website at:
https://library.municode.com/ca/riverside/codes/code_of_ordinances PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices January 2025 Page 11

Appendix 9.3

BMP OPERATION & MAINTENANCE AND TRAINING LOGS

PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices January 2025 Page 12

BMP OPERATION & MAINTENANCE LOG
Riverside Community Hospital Garage

Today’s Date:

Name of Person Performing Activity
(Printed):

Signature:

BMP Name
(As Shown in O&M Plan)
Brief Description of Implementation, Maintenance, and
Inspection Activity Performed

PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices January 2025 Page 13

TRAINING / EDUCATIONAL LOG

Date of Training/Educational Activity:

Name of Person Performing Activity
(Printed):

Signature:

Topic of Training/Educational Activity:

Name of Participant Signature of Participant

PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices January 2025 Page 14

Appendix 9.4

CITY OF RIVERSIDE

WATER QUALITY MANAGEMENT PLAN (WQMP) VERIFICATION SURVEY

Project Name/Site Address:

Responsible Party :

Contact Phone: Contact Email:

1. Have your contractors (landscape, maintenance, etc.) been educated regarding the applicable requirements to prevent pollution as outlined in the WQMP?

Yes No Name of Landscape/Maintenance Contractor:

Method of education (contract language, Copy of O&M, educational brochures, etc.):

2. Have the storm drains and inlets been inspected and maintained, at a minimum, annually prior to Oct 1?

Yes No Date of Last Inspection/Maintenance:

Maintenance conducted by:

3. Have you observed any runoff from the irrigation system?

Yes No If yes, how was the problem resolved?:

4. What type of Integrated Pest Management (IPM) practices are used on site?

5. Are native and/or drought tolerant plants established and considered for any new landscaping?

Yes No

6. Have the storm drain stencils been inspected annually for legibility prior to Oct. 1?

Yes No Total number of stencils on site:

How many inlets required restenciling / date of restenciling? /

7. Have education materials been distributed to the residents/tenants/contractors within the past year?
PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices January 2025 Page 15

Yes No Topic / Date of Distribution: /

Method of Distribution: newsletter, billing insert, etc.:

8. Is street sweeping conducted weekly?

Yes No Contractor:

9. Are trash areas in common area inspected daily?

Yes No

10. Have any vector concerns been observed (standing water, mosquito larvae, etc.). if yes, please contact Orange County Vector Control District at www.ocvcd.org.

Yes No

11. Have the LID BMPs been inspected and maintained per Manufacturer instructions? (attach invoices and inspection/maintenance forms).

Yes No

12. Have there been any issues with operation and maintenance of the LID BMPs units?

I certify that the above information is correct and that the BMPs for this project have been implemented and operated and maintained in accordance with the Operation and Maintenance (O&M) Plan on site and on file at the City.

Print Name of Responsible Party

_
Signatu
_
re (r
_
e
_
quire
_
d) Date
PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices Underground stormwater detention and infiltration systems must be inspected and maintained at regular intervals for purposes of performance and longevity.

Inspection
Inspection is the key to effective maintenance of CMP detention systems and is easily performed. Contech recommends ongoing, quarterly inspections. The rate at which the system collects pollutants will depend more on site specific activities rather than the size or configuration of the system.

Inspections should be performed more often in equipment washdown areas, in climates where sanding and/or salting operations take place, and in other various instances in which one would expect higher accumulations of sediment or abrasive/corrosive conditions. A record of each inspection is to be maintained for the life of the system.

Maintenance
CMP detention systems should be cleaned when an inspection reveals accumulated sediment or trash is clogging the discharge orifice.

Accumulated sediment and trash can typically be evacuated through the manhole over the outlet orifice. If maintenance is not performed as recommended, sediment and trash may accumulate in front of the outlet orifice. Manhole covers should be securely seated following cleaning activities. Contech suggests that all systems be designed with an access/inspection manhole situated at or near the inlet and the outlet orifice. Should it be necessary to get inside the system to perform maintenance activities, all appropriate precautions regarding confined space entry and OSHA regulations should be followed.

Systems are to be rinsed, including above the spring line, annually soon after the spring thaw, and after any additional use of salting agents, as part of the maintenance program for all systems where salting agents may accumulate inside the pipe.

Maintaining an underground detention or infiltration system is easiest when there is no flow entering the system. For this reason, it is a good idea to schedule the cleanout during dry weather.

The foregoing inspection and maintenance efforts help ensure underground pipe systems used for stormwater storage continue to function as intended by identifying recommended regular inspection and maintenance practices. Inspection and maintenance related to the structural integrity of the pipe or the soundness of pipe joint connections is beyond the scope of this guide.

ENGINEERED SOLUTIONS
NOTHING IN THIS CATALOG SHOULD BE CONSTRUED AS A WARRANTY. APPLICATIONS

SUGGESTED HEREIN ARE DESCRIBED ONLY TO HELP READERS MAKE THEIR OWN EVALUATIONS

AND DECISIONS, AND ARE NEITHER GUARANTEES NOR WARRANTIES OF SUITABILITY FOR ANY APPLICATION. CONTECH MAKES NO WARRANTY WHATSOEVER, EXPRESS OR IMPLIED, RELATED TO THE APPLICATIONS, MATERIALS, COATINGS, OR PRODUCTS DISCUSSED HEREIN. ALL IMPLIED

WARRANTIES OF MERCHANTABILITY AND ALL IMPLIED WARRANTIES OF FITNESS FOR ANY PARTICULAR PURPOSE ARE DISCLAIMED BY CONTECH. SEE CONTECH’S CONDITIONS OF SALE (AVAILABLE AT WWW.CONTECHES.COM/COS) FOR MORE INFORMATION

CMP DETENTION SYSTEMS
Underground stormwater detention and infiltration systems must be inspected and maintained at regular intervals for purposes of performance and longevity.

Inspection
Inspection is the key to effective maintenance of CMP detention systems and is easily performed. Contech recommends ongoing, annual inspections. Sites with high trash load or small outlet control orifices may need more frequent inspections. The rate at which the system collects pollutants will depend more on- site specific activities rather than the size or configuration of the system.

Inspections should be performed more often in equipment washdown areas, in climates where sanding and/or salting operations take place, and in other various instances in which one would expect higher accumulations of sediment or abrasive/ corrosive conditions. A record of each inspection is to be maintained for the life of the system.

NOTHING IN THIS CATALOG SHOULD BE CONSTRUED AS A WARRANTY. APPLICATIONS SUGGESTED HEREIN

ARE DESCRIBED ONLY TO HELP READERS MAKE THEIR OWN EVALUATIONS AND DECISIONS, AND ARE NEITHER GUARANTEES NOR WARRANTIES OF SUITABILITY FOR ANY APPLICATION. CONTECH MAKES NO WARRANTY

WHATSOEVER, EXPRESS OR IMPLIED, RELATED TO THE APPLICATIONS, MATERIALS, COATINGS, OR PRODUCTS DISCUSSED HEREIN. ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND ALL IMPLIED WARRANTIES OF FITNESS FOR ANY PARTICULAR PURPOSE ARE DISCLAIMED BY CONTECH. SEE CONTECH’S CONDITIONS OF SALE (AVAILABLE AT WWW.CONTECHES.COM/COS) FOR MORE INFORMATION.

Maintenance
CMP detention systems should be cleaned when an inspection reveals accumulated sediment or trash is clogging the discharge orifice.

Annual inspections are best practice for all underground systems.

During this inspection if evidence of salting/de-icing agents is observed within the system, it is best practice for the system to be rinsed, including above the spring line soon after the spring thaw as part of the maintenance program for the system.

Maintaining an underground detention or infiltration system is easiest when there is no flow entering the system. For this reason, it is a good idea to schedule the cleanout during dry weather.

Contech
®
CMP Detention Inspection and Maintenance Guide

ENGINEERED SOLUTIONS

CMP DETENTION SYSTEMS
PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices - 6 -

Appendix 10: Educational Materials
BMP Fact Sheets, Maintenance Guidelines, and Other End-User BMP Information

PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices Drainage System Maintenance SC-44
September 2014 California Stormwater BMP Handbook 1 of 7 Industrial and Commercial
www.casqa.org
Description
As a consequence of its function, the
stormwater drainage facilities on site convey
stormwater that may contain certain pollutants
either to the offsite conveyance system that
collects and transports urban runoff and
stormwater, or directly to receiving waters. The
protocols in this fact sheet are intended to
reduce pollutants leaving the site to the offsite
drainage infrastructure or to receiving waters
through proper on-site conveyance system
operation and maintenance. The targeted
constituents will vary depending on site
characteristics and operations.

Approach
Successful implementation depends on
effective training of employees on applicable
BMPs and general pollution prevention
strategies and objectives.

General Pollution Prevention Protocols
 Maintain catch basins, stormwater inlets,
and other stormwater conveyance
structures on a regular basis to remove
pollutants, reduce high pollutant
concentrations during the first flush of
storms, prevent clogging of the downstream
conveyance system, restore catch basins’
sediment trapping capacity, and ensure the
system functions properly hydraulically to
avoid flooding.
 Develop and follow a site specific drainage
system maintenance plan that describes
maintenance locations, methods, required
equipment, water sources, sediment
collection areas, disposal requirements, and
any other pertinent information.

Good Housekeeping
Illicit Connections and Discharges
 Look for evidence of illegal discharges or
illicit connections during routine
maintenance of conveyance system and
drainage structures:

Objectives

 Cover
 Contain
 Educate
 Reduce/Minimize
Targeted Constituents
Sediment 
Nutrients 
Trash 
Metals 
Bacteria 
Oil and Grease 
Organics 
Minimum BMPs Covered
Good Housekeeping 
Preventative
Maintenance 
Spill and Leak
Prevention and
Response

Material Handling &
Waste Management
Erosion and Sediment
Controls
Employee Training
Program 
Quality Assurance
Record Keeping 

PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices Drainage System Maintenance SC-44
September 2014 California Stormwater BMP Handbook 2 of 7 Industrial and Commercial
www.casqa.org
 Identify evidence of spills such as paints, discoloring, odors, etc.  Record locations of apparent illegal discharges/illicit connections.  Track flows back to potential discharges and conduct aboveground inspections.

This can be done through visual inspection of upgradient manholes or alternate techniques including zinc chloride smoke testing, fluorometric dye testing, physical inspection testing, or television camera inspection.  Eliminate the discharge once the origin of flow is established.  Stencil or demarcate storm drains, where applicable, to prevent illegal disposal of pollutants. Storm drain inlets should have messages such as “Dump No Waste Drains to Stream” or similar stenciled next to them to warn against ignorant or intentional dumping of pollutants into the storm drainage system.  Refer to fact sheet SC-10 Non-Stormwater Discharges for additional information.

Illegal Dumping
 Inspect and clean up hot spots and other storm drainage areas regularly where illegal dumping and disposal occurs.
 Establish a system for tracking incidents. The system should be designed to identify the following:
 Illegal dumping hot spots;
 Types and quantities (in some cases) of wastes;
 Patterns in time of occurrence (time of day/night, month, or year);  Mode of dumping (abandoned containers, “midnight dumping” from moving vehicles, direct dumping of materials, accidents/spills); and  Responsible parties.
 Post “No Dumping” signs in problem areas with a phone number for reporting dumping and disposal. Signs should also indicate fines and penalties for illegal dumping.
 Refer to fact sheet SC-10 Non-Stormwater Discharges for additional information.

Preventative Maintenance
Catch Basins/Inlet Structures
 Staff should regularly inspect facilities to ensure compliance with the following:
 Immediate repair of any deterioration threatening structural integrity.  Cleaning before the sump is 40% full. Catch basins should be cleaned as frequently as needed to meet this standard.

PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices Drainage System Maintenance SC-44
September 2014 California Stormwater BMP Handbook 3 of 7 Industrial and Commercial
www.casqa.org
 Clean catch basins, storm drain inlets, and other conveyance structures before the wet season to remove sediments and debris accumulated during the summer.  Conduct inspections more frequently during the wet season for problem areas where sediment or trash accumulates more often. Prioritize storm drain inlets; clean and repair as needed.
 Keep accurate logs of the number of catch basins cleaned.  Store wastes collected from cleaning activities of the drainage system in appropriate containers or temporary storage sites in a manner that prevents discharge to the storm drain.
 Dewater the wastes if necessary with outflow into the sanitary sewer if permitted.

Water should be treated with an appropriate filtering device prior to discharge to the sanitary sewer. If discharge to the sanitary sewer is not allowed, water should be pumped or vacuumed to a tank and properly disposed. Do not dewater near a storm drain or stream.

Storm Drain Conveyance System
 Locate reaches of storm drain with deposit problems and develop a flushing schedule that keeps the pipe clear of excessive buildup.
 Collect and pump flushed effluent to the sanitary sewer for treatment whenever possible.

Pump Stations
 Clean all storm drain pump stations prior to the wet season to remove silt and trash.  Do not allow discharge to reach the storm drain system when cleaning a storm drain pump station or other facility.
 Conduct routine maintenance at each pump station.
 Inspect, clean, and repair as necessary all outlet structures prior to the wet season.

Open Channel
 Modify storm channel characteristics to improve channel hydraulics, increase pollutant removals, and enhance channel/creek aesthetic and habitat value.  Conduct channel modification/improvement in accordance with existing laws. Any person, government agency, or public utility proposing an activity that will change the natural state of any river, stream, or lake in California, must enter into a Steam or Lake Alteration Agreement with the Department of Fish and Wildlife. The developer-applicant should also contact local governments (city, county, special districts), other state agencies (SWRCB, RWQCB, Department of Forestry, Department of Water Resources), and Army Corps of Engineers and USFWS.

Spill Response and Prevention Procedures
 Keep your spill prevention control plan up-to-date.

PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices Drainage System Maintenance SC-44
September 2014 California Stormwater BMP Handbook 4 of 7 Industrial and Commercial
www.casqa.org
 Investigate all reports of spills, leaks, and/or illegal dumping promptly.  Place a stockpile of spill cleanup materials where it will be readily accessible or at a central location.
 Clean up all spills and leaks using “dry” methods (with absorbent materials and/or rags) or dig up, remove, and properly dispose of contaminated soil.

Employee Training Program
 Educate employees about pollution prevention measures and goals.  Train employees how to properly handle and dispose of waste using the source control BMPs described above.
 Train employees and subcontractors in proper hazardous waste management.  Use a training log or similar method to document training.  Ensure that employees are familiar with the site’s spill control plan and/or proper spill cleanup procedures.
 Have staff involved in detection and removal of illicit connections trained in the following:
 OSHA-required Health and Safety Training (29 CFR 1910.120) plus annual refresher training (as needed).
 OSHA Confined Space Entry training (Cal-OSHA Confined Space, Title 8 and Federal OSHA 29 CFR 1910.146).
 Procedural training (field screening, sampling, smoke/dye testing, TV inspection).

Quality Assurance and Record Keeping
 Keep accurate maintenance logs that document minimum BMP activities performed for drainage system maintenance, types and quantities of waste disposed of, and any improvement actions.
 Keep accurate logs of spill response actions that document what was spilled, how it was cleaned up, and how the waste was disposed.
 Keep accurate logs of illicit connections, illicit discharges, and illegal dumping into the storm drain system including how wastes were cleaned up and disposed.  Establish procedures to complete logs and file them in the central office.

Potential Limitations and Work-Arounds
Provided below are typical limitations and recommended “work-arounds” for drainage system maintenance:

PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices Drainage System Maintenance SC-44
September 2014 California Stormwater BMP Handbook 5 of 7 Industrial and Commercial
www.casqa.org
 Clean-up activities may create a slight disturbance for local aquatic species. Access to items and material on private property may be limited. Trade-offs may exist between channel hydraulics and water quality/riparian habitat. If storm channels or basins are recognized as wetlands, many activities, including maintenance, may be subject to regulation and permitting.
 Perform all maintenance onsite and do not flush accumulated material downstream to private property or riparian habitats.
 Storm drain flushing is most effective in small diameter pipes (36-inch diameter pipe or less, depending on water supply and sediment collection capacity). Other considerations associated with storm drain flushing may include the availability of a water source, finding a downstream area to collect sediments, and liquid/sediment disposal.
 Develop and follow a site specific drainage system maintenance plan that describes maintenance locations, methods, required equipment, water sources, sediment collection areas, disposal requirements, and any other pertinent information.
 Regulations may include adoption of substantial penalties for illegal dumping and disposal.
 Do not dump illegal materials anywhere onsite.
 Identify illicit connections, illicit discharge, and illegal dumping.  Cleanup spills immediately and properly dispose of wastes.  Local municipal codes may include sections prohibiting discharge of soil, debris, refuse, hazardous wastes, and other pollutants into the sanitary sewer system.  Collect all materials and pollutants accumulated in drainage system and dispose of according to local regulations.
 Install debris excluders in areas with a trash TMDL.

Potential Capital Facility Costs and Operation & Maintenance Requirements
Facilities
 Capital costs will vary substantially depending on the size of the facility and characteristics of the drainage system. Significant capital costs may be associated with purchasing water trucks, vacuum trucks, and any other necessary cleaning equipment or improving the drainage infrastructure to reduce the potential .  Developing and implementing a site specific drainage system maintenance plan will require additional capital if a similar program is not already in place.

PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices Drainage System Maintenance SC-44
September 2014 California Stormwater BMP Handbook 6 of 7 Industrial and Commercial
www.casqa.org
Maintenance
 Two-person teams may be required to clean catch basins with vactor trucks.  Teams of at least two people plus administrative personnel are required to identify illicit discharges, depending on the complexity of the storm sewer system.  Arrangements must be made for proper disposal of collected wastes.  Technical staff are required to detect and investigate illegal dumping violations.  Methods used for illicit connection detection (smoke testing, dye testing, visual inspection, and flow monitoring) can be costly and time-consuming. Site-specific factors, such as the level of impervious area, the density and ages of buildings, and type of land use will determine the level of investigation necessary.

Supplemental Information
Storm Drain Flushing
Flushing is a common maintenance activity used to improve pipe hydraulics and to remove pollutants in storm drainage systems. Flushing may be designed to hydraulically convey accumulated material to strategic locations, such as an open channel, another point where flushing will be initiated, or the sanitary sewer and the treatment facilities, thus preventing re-suspension and overflow of a portion of the solids during storm events. Flushing prevents “plug flow” discharges of concentrated pollutant loadings and sediments. Deposits can hinder the designed conveyance capacity of the storm drain system and potentially cause backwater conditions in severe cases of clogging.

Storm drain flushing usually takes place along segments of pipe with grades that are too flat to maintain adequate velocity to keep particles in suspension. An upstream manhole is selected to place an inflatable device that temporarily plugs the pipe. Further upstream, water is pumped into the line to create a flushing wave. When the upstream reach of pipe is sufficiently full to cause a flushing wave, the inflated device is rapidly deflated with the assistance of a vacuum pump, thereby releasing the backed up water and resulting in the cleaning of the storm drain segment.

To further reduce impacts of stormwater pollution, a second inflatable device placed well downstream may be used to recollect the water after the force of the flushing wave has dissipated. A pump may then be used to transfer the water and accumulated material to the sanitary sewer for treatment. In some cases, an interceptor structure may be more practical or required to recollect the flushed waters.

It has been found that cleansing efficiency of periodic flush waves is dependent upon flush volume, flush discharge rate, sewer slope, sewer length, sewer flow rate, sewer diameter, and population density. As a rule of thumb, the length of line to be flushed should not exceed 700 feet. At this maximum recommended length, the percent removal efficiency ranges between 65-75% for organics and 55-65% for dry weather grit/inorganic material. The percent removal efficiency drops rapidly beyond that.

Water is commonly supplied by a water truck, but fire hydrants can also supply water.

To make the best use of water, it is recommended that reclaimed water be used if allowed or that fire hydrant line flushing coincide with storm sewer flushing.

PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices Drainage System Maintenance SC-44
September 2014 California Stormwater BMP Handbook 7 of 7 Industrial and Commercial
www.casqa.org
References and Resources
City of Seattle, Seattle Public Utilities Department of Planning and Development, 2009.

Stormwater Manual Vol. 1 Source Control Technical Requirements Manual.

Knox County Tennessee Stormwater Management Manual Chapter 5 Drainage System Maintenance, 2008. Available online at:
http://www.knoxcounty.org/stormwater/manual/Volume%201/knoxco_swmm_v1_cha p5_jan2008.pdf.

US EPA. Storm Drain System Cleaning, 2012. Available online at:
http://cfpub.epa.gov/npdes/stormwater/menuofbmps/index.cfm?action=browse&Rbut ton=detail&bmp=102.

PR-2024-001701 (GPA, SPA, RZ, DR) Exhibit 13 - EIR Addendum and appedices

Riverside City CouncilMay 20, 2025

Riverside City Council
May 20, 2025