Agenda packet — San Dimas City Council, June 25, 2024 (part 2 of 2)

Introduce Ordinance 1306 Amending Chapter 14.11 (Stormwater Management and Discharge) & Chapter 14.13 (Low Impact Development) of the San Dimas Municipal Code to Implement Updates to the Los Angeles Regional Water Quality Control Board’s Municipal Separate Storm Sewer System (MS4) Permit Page 11
For the Meeting of June 25, 2024
Lauren Marshall
Sr. Management Analyst
Attachments:

1. Ordinance 1306 - Stormwater Ordinance Amendment

2. Redline of amendments made by Ordinance 1306

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ATTACHMENT 1
ORDINANCE 1306

AN ORDINANCE OF THE CITY COUNCIL OF THE CITY OF SAN DIMAS, CALIFORNIA, AMENDING SAN DIMAS MUNICIPAL CODE CHAPTER 14.11 AND CHAPTER 14.13 of TITLE 14 (WATER AND SEWERS) UPDATING THE

STORMWATER MANAGEMENT AND DISCHARGE AND LOW IMPACT

DEVELOPMENT (LID) REQUIREMENTS FOR NEW DEVELOPMENT AND

REDEVELOPMENT PROJECTS AND INCORPORATING THE REGIONAL
PHASE I MUNICIPAL SEPARATE STORM SEWER SYSTEM (MS4) PERMIT

REQUIREMENTS ASSOCIATED WITH DISCHARGE AND CONNECTION TO THE STORM DRAIN SYSTEM, AND CONTROL OF STORMWATER AND NONSTORMWATER RUNOFF WHEREAS, the City of San Dimas is authorized by Article XI, §5 and §7 of the State Constitution to exercise the police power of the State by adopting regulations to promote public health, public safety, and general prosperity.

WHEREAS, the City of San Dimas has authority under the California Water Code to adopt and enforce ordinances imposing conditions, restrictions, and limitations with respect to any activity which might degrade the quality of waters of the State.

WHEREAS, the City is a permittee under the " Waste Discharge Requirements for and National Pollutant Discharge Elimination System ( NPDES) Permit for Municipal Separate Storm Sewer System ( MS4) Discharges within the Coastal Watersheds of Los Angeles and Ventura Counties, issued by the California Regional Water Quality Control Board — Los Angeles Region" ( Order No. R4- 2021- 0105), and also serves as Waste Discharge Requirements pursuant to Article 4, Chapter 4, Division 7 of the California Water Code ( commencing with section 13260); and section 402 of the Federal Clean Water Act ( CWA) and implementing regulations adopted by the U. S. EPA and Chapter 5. 5, Division 7 of the Water Code (commencing with section 13370).

WHEREAS, the Regional Phase I MS4 Permit amends certain requirements regulating the discharge of stormwater and urban runoff into the City' s storm drain facilities and control of stormwater and non- stormwater runoff.

WHEREAS, LID practices are widely recognized as an effective and sustainable approach to managing the quantity and quality of stormwater and non -storm water runoff by establishing standards and practices to maintain or restore the natural hydrologic character of a development site, reduce off-site runoff, improve water quality, and provide groundwater recharge.

NOW, THEREFORE, the CITY COUNCIL of the CITY OF SAN DIMAS, California, does ordain as follows:

SECTION I. Chapter 14.11 of the San Dimas Municipal Code is hereby amended to read, in its entirety, as follows:

San Dimas, California Municipal Code Title 14 WATER AND SEWERS Chapter 14.11 STORMWATER MANAGEMENT AND DISCHARGE

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Ordinance 1306 Page 2
Municipal Code Text Amendment Section 14.11 and 14.13
June 25, 2024

14.11.010 Definitions.

14.11.020 Responsibility for Administration.

14.11.030 General Provisions.

14.11.040 Prohibited Discharges and Activities.

14.11.050 Prohibited Connections to the MS4.

14.11.060 Requirements for Existing Properties.

14.11.070 Requirements for Industrial and Commercial Facilities.

14.11.080 Low Impact Development Standards for New Development and Redevelopment.

14.11.090 Requirements for Construction Projects.

14.11.100 Municipal Facility Activities.

14.11.110 Public Information and Participation Program.

14.11.120 Inspections and Fees.

14.11.130 Enforcement and Penalties.

14.11.140 Disclaimer of Liability.

14.11.150 Taking.

14.11.010 Definitions.

In addition to the Glossary of Terms found in Attachment D to the Los Angeles County Municipal Storm Water Permit Order No. R4-2021-0105, the following words and phrases shall have the following specific meanings:
“Adverse Impact” means any detrimental effect upon water quality or beneficial uses caused by a discharge of loading of a pollutant or pollutants.
“Area susceptible to runoff” means any surface directly exposed to precipitation or in the path of runoff caused by precipitation that leads directly to neighboring properties or to the street. “Areas of Special Biological Significance” means all those areas designated by the State Water Board as ocean areas requiring protection of species or biological communities to the extent that maintenance of natural water quality is assured. All Areas of Special Biological Significance are also classified as a subset of State Water Quality Protection Areas. "Authorized enforcement officer'' means the City's code enforcement officer and the Director of Public Works, including any person so designated by the Director of Public Works.

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“Authorized Non-Stormwater Discharge” means discharges that are not composed entirely of stormwater and that are either: (1) separately regulated by an Industrial or General NPDES permit and allowed to be discharges into the MS4 when in compliance with all NPDES permit conditions; (2) separately regulated by a conditional waiver of water discharge requirements (WDRs) or WDRs for agricultural lands; (3) authorized by U.S. EPA pursuant to sections 104(a) or 104(b) of Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) that either (i) will comply with water quality standards as applicable or relevant and appropriate requirements (ARARs) under section 121(d)(2) of CERCLA; or (ii) are subject to (a) a written waiver of ARARs by U.S. EPA pursuant to section 121(d)(4) of CERCLA or (b) a written determination by U.S EPA that compliance with ARARs is not practicable considering the exigencies of the situation, pursuant to 40 CFR section 300.415(j); or (4) necessary for emergency response purposes, including discharges from emergency firefighting activities. “Automotive Service Facility” means a facility that is categorized by any one of the following Standard Industrial Classification (SIC) and North American Industry Classification System (NAICS) codes. For inspection purposes, facilities with SIC codes 5013, 5014, 5511, and 5541, will not be subject to inspection provided that these facilities have no outside activities or materials that may be exposed to stormwater.

SIC Code Corresponding NAICS Code
5013 425120, 441310, 425110, and 423120
5014 425120, 425110, 423130, and 441320
5511 441110
5541 447110 and 447190
7532 811121
7533 811112
7534 326212 and 811198
7536 811122
7537 811113
7538 811111
7539 811198 and 811118
"Best management practices" ("BMPs") means practices or physical devices or systems designed to prevent or reduce pollutant loading from stormwater or non-stormwater discharges to receiving waters.
"City" means the City of San Dimas.
"Code" means the San Dimas Municipal Code.
“Conditionally Exempt Non-Stormwater Discharge” means certain categories of discharges that are not composed entirely of stormwater and that are allowed by the Los Angeles Water Board to discharge into the MS4, if the discharge is in compliance with all specified requirements; are not otherwise regulated by an individual or general NPDES permit; and are essential public services that are directly or indirectly required by other State or federal statute and/or regulation. These include non-stormwater discharges such as from drinking water supplier distribution system releases. Conditionally exempt essential non-stormwater discharges may contain minimal amounts of pollutants, however, when in compliance with industry standard BMPs and control measures, do not result in significant environmental effects.

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“Construction Activity” means any construction or demolition activity, clearing, grading, grubbing, or excavation or any other activity that result in land disturbance. Construction does not include emergency construction activities required to immediately protect public health and safety or routine maintenance activities required to maintain the integrity of structures by performing minor repair and restoration work, maintain the original line and grade, hydraulic capacity, or original purposes of the facility. See “Routine Maintenance” definition for further explanation. Where clearing, grading, or excavating of underlying soil takes place during a repaving operation, State General Construction Permit coverage by the State of California General Permit for Storm Water Discharges Associated with Industrial Activities or for Stormwater Discharges Associated with Construction Activities is required if more than one acre is disturbed or the activities are part of a larger plan.
“Construction General Permit” means General Permit for Storm Water Discharges Associated with Construction and Land Disturbance Activities. General NPDES permit issued by the State Water Board, which authorizes the discharge of stormwater from construction activities under certain conditions.
“Control” means to minimize, reduce, eliminate, or prohibit by technological, legal, contractual or other means, the discharge of pollutants from an activity or activities. “Dechlorinated/Debrominated Swimming Pool Discharge” means swimming pool discharges with do not contain measurable quantities of chlorine or bromine and do not contain any detergents, wastes, or additional chemicals not typically found in swimming pool water. The term does not include swimming pool filter backwash.
"Discharge" means without qualification the release or a pollutant or pollutants to the MS4. "Disturbed area" means an area altered as a result of clearing, grading and/or excavation of earth. “Drinking Water Distribution System Discharges” means sources of flows from drinking water storage, supply, and distribution systems including flows from system failures, pressure releases, system maintenance, distribution line testing, fire hydrant flow testing; and flushing and dewatering of pipes, reservoirs, vaults, and minor non-invasive well maintenance activities not involving chemical addition(s). It does not include wastewater discharges from activities that occur at wellheads, such as well construction, well development (i.e., aquifer pumping tests, well purging, etc.), or major well maintenance.
“Emergency Situation” means any incident, whether natural, technological, or human-caused, that requires responsive action to protect life of property. "Gray water" means water that is discharged from sinks, showers, tubs, washing machines, dishwashers, and garbage disposals.
"Hazardous waste" means any material defined as hazardous by Chapter 6.95 of the California Health and Safety Code and any substance designated pursuant to 40 CFR 302. This includes unlisted hazardous substances that are solid wastes, as defined in 40 CFR 261.2, that are not excluded from regulation as hazardous wastes under 40 CFR 261.4(b) if they exhibit any of the characteristics identified in 40 CFR 261.20 through 261.24.

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"Illicit connection" means any man-made conveyance that is connected to the storm drain system without a permit, excluding roof drains and other similar type connections. Examples include channels, pipelines, conduits, inlets, or outlets that are connected directly to the storm drain system.
"Illicit discharge" means any discharge into the MS4 that is prohibited under local, state, or federal statues, ordinances, codes, or regulations. The term illicit discharge includes any non-stormwater discharge, except those authorized non-stormwater discharges; conditionally exempt nonstormwater discharges; and non-stormwater discharges resulting from natural flows specifically identified in this Chapter.
“Industrial General Permit” means a General Permit for Storm Water Discharges Associated with Industrial Activities. General NPDES permit issued by the State Water Board, which authorizes the discharge of stormwater from certain industrial activities under certain conditions. “Industrial/Commercial Facility” means any facility involved and/or used in the production, manufacture, storage, transportation, distribution, exchange or sale of goods and/or commodities, and any facility involved and/or used in providing professional and non-professional services. This category of facilities includes, but is not limited to, any facility defined by either the Standard Industrial Classifications (SIC) or the North American Industry Classification System (NAICS). “LID” means Low Impact Development. LID consists of building and landscape features designed to retain or filter stormwater runoff.
“Municipal Separate Storm Sewer System (MS4)” means a conveyance or system of conveyances (including roads with drainage systems, municipal streets, catch basins, curbs, gutter, ditches, man-made channels, or storm drains) (40 CFR § 122.26(b)(8)) that is the following:

1. Owned or operated by a state, city, town, borough, county, parish, district, association, or other public body (created by or pursuant to State law) having jurisdiction over disposal of sewage, industrial wastes, stormwater, or other wastes, including special districts under State law such as a sewer district, flood control district or drainage district, or similar entity, or an Indian tribe or an authorized Indian tribal organization, or a designated and approved management agency under section 208 of the CWA that discharges to waters of the United States;

2. Designed or used for collecting or conveying stormwater; and

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“Planning Priority Projects” means development projects subject to Permittee conditioning and approval for the design and implementation of post-construction controls to mitigate stormwater pollution, prior to completion of the project(s).
“Regional Board” means the California Regional Water Quality Control Board, Los Angeles Region.
“Sidewalk Rinsing” means low-volume pressure washing of paved pedestrian walkways with average water usage of 0.006 gallons per square foot, with no cleaning agents, and proper disposal of all debris collected.
"Storm Drain System" means those facilities that convey stormwater runoff and suspended solids to the waters of the United States, including streets, alleys, roads, ditches, curbs, gutters, catch basins, conduits, streams, channels, creeks, and rivers. "Stormwater'' means water that originates from atmospheric moisture (rainfall, hail, snow, or snowmelt) and that falls onto land, water, or other surfaces. "Stormwater Pollution Prevention Plan" ("SWPPP") means a plan, as required by a state general permit for discharges of stormwater (e.g., Construction General Permit or Industrial General Permit), identifying potential pollutant sources and describing the design, placement, and implementation of BMPs, to effectively prevent non-stormwater discharges and reduce pollutants in stormwater discharges from activities covered by the general permit. "Stormwater Runoff “means the part of precipitation (rainfall or snowmelt) that travels across a surface to the storm drain system or receiving waters.
"Urban Runoff” means surface water flow produced by storm and non-storm events. Non-storm events include flow from residential, commercial, or industrial activities involving the use of potable and non-potable water.

14.11.020 Responsibility for Administration.

This Chapter shall be administered by the office of the City Engineer. (Ord. 1064 4,1997)

14.11.030 General Provisions.

A. The purpose and intent of this chapter is to protect the health and safety of the residents of the City by protecting the beneficial uses, marine habitats, and ecosystems of receiving water from pollutants carried by stormwater and non-stormwater discharges. The intent of the chapter is to enhance and protect the water quality of receiving waters consistent with the Clean Water Act.

B. The provisions of this chapter shall apply to the discharge, deposit, addition, or disposal of any non-stormwater, stormwater and/or runoff to the storm drain system and/or receiving waters within the City.

C. The City Engineer shall establish and enforce uniform standards, guidelines, and/or criteria for specific discharges, connections and/or BMPs.14.11.040 Prohibited Discharges and Activities.

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14.11.040 Prohibited Discharges and Activities.

A. Except as otherwise conditionally authorized by the Permit or any other NPDES permit, waiver or waste discharge order issued by the U.S. EPA, the State Board, or a regional board, provided that the discharger is in full compliance with all requirements of the permit, waiver or order and other applicable laws and regulations, including the provisions of this chapter, and subject to any requirements specified by the Director, no person shall do the following:

1. Discharge non-stormwater to the City's storm drain system or to receiving waters except in compliance with the requirements of this Chapter;

2. Cause, allow, or facilitate any prohibited discharge; and

3. Discharge, cause, allow, or facilitate any discharge that may cause or threaten to cause a condition of pollution or nuisance as defined in Water Code section 13050, that may cause, threaten to cause or contribute to an exceedance of any water quality standard in any Statewide Water Quality Control Plan, California Toxics Rule, or Basin Plan, or that may cause or contribute to the violation of any receiving water limitation.

B. Pursuant to the Permit, discharges which may be conditionally authorized subject to best management practices and other restrictions or prohibitions, include but are not limited to the following types of discharges:

1. Authorized non-stormwater discharges separately regulated by an individual or general NPDES permit.

2. Authorized non-stormwater discharges separately regulated by a conditional waiver or WDRs for agricultural lands.

3. Temporary non-stormwater discharges authorized pursuant to sections 104(a) or 104(b) of the CERCLA that either: (i) will comply with water quality standards as applicable or relevant and appropriate requirements (“ARARs”) under section 121(d)(2) of CERCLA; or (ii) are subject to either (a) a written waiver of ARARs pursuant to section 121(d)(4) of CERCLA or (b) a written determination that compliance with ARARs is not practicable considering the exigencies of the situation pursuant to 40 CFR. Section 300.415(j).

4. Authorized non-stormwater discharges from emergency firefighting activities (i.e., discharges resulting from water use necessary for the protection of life or property from fire).

5. Natural flows to include the following:
a. Natural springs;
b. Flows from riparian habitats and wetlands;
c. Diverted stream flows, authorized by the State Water Board or Los Angeles Water Board;
d. Uncontaminated ground water infiltration; and
e. Rising ground waters, where ground water seepage is not otherwise covered by a NPDES permit.

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b. Conditionally Exempt Non-Essential Non-Stormwater Discharges to include the following:
i. Dewatering of lakes.
ii. Landscape irrigation.
iii. Dechlorinated/debrominated swimming pool/spa discharges not otherwise regulated by a separate NPDES permit.
iv. Dewatering of decorative fountains.
v. Non-commercial car washing by residents or by non-profit organizations.
vi. Street/sidewalk wash water.
vii. Short-term releases of potable water with no additives or dyes for filming purposes.
viii. Potable wash water used to clean reservoir covers. c. Non-Stormwater Discharges to an ASBS are allowed as follows:
i. One of the conditionally exempt non-stormwater discharge categories in part 6.a. above.
ii. Essential for emergency response purposes, structural stability, and slope stability, which may include but are not limited to the following discharges:
a. Discharges associated with emergency firefighting
operations (i.e., discharges resulting from water use
necessary for the protection of life or property from fire). b. Foundation and footing drains;
c. Water from crawl space or basement pumps; and
d. Hillside dewatering.
iii. Naturally occurring discharges as follows:
a. Naturally occurring groundwater seepage via the MS4; b. Non-anthropogenic flows from a naturally occurring stream via a culvert or MS4, if there are no contributions of anthropogenic runoff.

C. The City Engineer may limit or prohibit any discharge which is conditionally authorized by the Permit if the discharge is a source of pollutants or causes or contributes to an exceedance of applicable receiving water limitations or water quality-based effluent limitations, including but not limited to imposing conditions on such discharge, requiring control measures and other actions to reduce pollutants, requiring diversion of the discharge to the sanitary sewer, or requiring pretreatment.

D. The City Engineer may require any person to obtain a permit from the City before discharging or causing, allowing, or facilitating any discharge to the storm drain system. It is unlawful to discharge, cause, allow, or facilitate any discharge to the storm drain system in violation of any permit so required.

E. Littering and other discharge of polluting or damaging substances are prohibited.

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property so that the same may or does become a pollutant which may or does enter the storm drain system or receiving waters, except when such materials are placed in containers, bags, recycling bins, or other lawfully established waste disposal facilities protected from stormwater or runoff.

2. No person shall cause the disposal of hazardous materials or hazardous wastes into trash containers used for municipal trash disposal.

3. No person shall cause to be discharged to the storm drain system or to receiving waters any pesticide, fungicide, or herbicide prohibited by the U.S. EPA or the California Department of Pesticide Regulation.

4. No person shall cause the accumulation of pollutants, leaves, dirt, or other landscape debris into a street, alley, catch basin, culvert, curb, gutter, inlet, ditch, natural watercourse, flood control channel, canal, storm drain, or any fabricated or natural conveyance so that the same may or does become a pollutant which may or does enter the storm drain system or receiving waters.

5. No person shall cause the disposal of sanitary or septic waste or sewage into the storm drain system from any property or residence or any type of recreational vehicle, camper, bus, boat, holding tank, portable toilet, vacuum truck, or other mobile source of waste holding tank, container, or device.

6. No person shall discharge or cause to be discharged anything that would result in or contribute to a violation of the City's NPDES permit and any amendment, revision or re-issuance, thereof, either separately or when combined with other discharges.

F. No person shall conduct any industrial activity in the City without obtaining all the permits required by state or federal law, including a NPDES General Industrial Activity Storm Water Permit, when required.

14.11.050 Prohibited Connections to the MS4.

A. The installation or use of illicit connections prohibited. No person shall install, maintain, or use any connection to the storm drain system or act, cause, permit or suffer any non-stormwater to be discharged or conveyed through a connection to the storm drain system unless the connection has been permitted by the City Engineer This prohibition is retroactive and applies to connections made in the past, regardless of whether made under a permit or other authorization, or whether permissible under the laws or practices applicable or prevailing at the time of the connection.

B. Removal of illicit connection from the storm drain system. If any person fails to remove an illicit connection upon notification by the City Engineer, or upon revocation of a connection permit, the City Engineer may direct the removal of such connection from the storm drain system. Additionally, the City Engineer may pursue the recovery of costs for such removal pursuant to 14.11.130.
(Ord. 1112 § 1, 2000; Ord. 1064 § 4, 1997)

14.11.060 Requirements for Existing Properties.

Any owner or occupant of property within the City shall comply with the following best management practices:

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A. Any person engaged in activities which will or may result in pollutants entering the City storm drain system shall undertake all control measures and BMPs as the City Engineer may require to reduce such pollutants. Premises with a high potential threat of discharge may be required to implement a monitoring program meeting standards established by the City. Where best management practices guidelines or requirements have been adopted by any Federal, State, regional, and/or city agency, for any activity, operation, or facility which may cause or contribute to stormwater pollution or contamination, illicit discharges, and/or discharges of non-stormwater to the storm drain system, every person undertaking such activity or operation, or owning or operating such facility shall comply with such guidelines or requirements as may be identified by the City Engineer.

B. Installation of structural BMPs. No person shall install a structural BMP for the purpose of treating, neutralizing, disposing of monitoring or diverting to the sanitary sewer system any runoff without the approval of the City Engineer and of the Los Angeles County Sanitation District or any successor thereto. Such facilities may be subject to plan review, application, and issuance of operating permits.

C. BMPs to be consistent with environmental goals. No person shall install or implement a BMP that transfers pollutants to air, groundwater, surface soils, and/or other media in a manner inconsistent with applicable environmental laws and regulations.

D. The City Engineer may require any person responsible for any industrial or commercial facility of new or redevelopment project to submit documentation demonstrating coverage by and compliance with any applicable permit, including copies of any notice of intent, stormwater pollution prevention plans, inspection reports, monitoring results, and other information deemed necessary to assess compliance with this Chapter or any NPDES permit. Each discharger identified in an individual NPDES permit relating to stormwater discharges shall comply with and undertake all activities required by such permit.

E. The City Engineer may require any person responsible for any industrial or commercial facility or new development or redevelopment project to enter into an agreement for the operation and maintenance of any structural control measures and to record such agreement with the County Recorder’s office.

F. The following BMPs are required of every owner or occupant of any property:

1. No person shall leave, deposit, discharge, dump, or otherwise expose any chemical, fuel, animal waste, garbage, batteries, and/or septic waste in an area where actual or potential discharge to the City streets or the storm drain system may occur. Any spills, discharge, or residues shall be removed as soon as possible and disposed of properly.

2. Runoff from landscape irrigation, air conditioning condensate, water-line flushing, foundation/footing drains, individual residential car washing, dechlorinated/debrominated swimming pool/spa discharges, and sidewalk washing shall be conducted in a manner which minimizes or eliminates the possibility of pollutant discharges reaching the City storm drain system or receiving waters.

3. Runoff from washing paved areas, including but not limited to parking lots, on industrial or commercial property is prohibited unless specifically required by federal, state, or local health or safety codes and not in violation of any other provision of this

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code. Runoff from authorized washing of paved areas shall be minimized to the extent practicable.

4. Objects, such as motor vehicle parts containing grease, oil, or other hazardous materials, and unsealed receptacles containing hazardous materials, shall not be stored in area exposed to stormwater or otherwise susceptible to runoff.

5. Any machinery or equipment which is to be repaired or maintained in areas exposed to stormwater or otherwise susceptible to runoff shall be provided with containment areas to control leaks, spills, or discharges.

6. All motor vehicle parking lots with more than 25 parking spaces and located in areas exposed to stormwater or otherwise susceptible to runoff shall have debris removed by regular sweeping or other equally effective measures. Such debris shall be collected and properly disposed of.

7. Motor vehicle parking lots with a gravel/sediment base to implement BMPs to prevent the discharge of gravel and sediment to the MS4. (Ord. 1064 § 4, 1997) G. The discharge of gray water to street or storm drains is prohibited.

14.11.070 Industrial and Commercial Facilities
A. The following discharges from industrial or commercial activities are prohibited unless the discharge is in compliance with the provisions of this chapter:

1. Discharge of wash waters to the storm drain system from the cleaning of gas stations, auto repair garages, or other types of auto repair facilities;

2. Discharge of wastewater to the storm drain system from mobile auto washing, steam cleaning, mobile carpet cleaning, or other such mobile commercial and industrial operations;

3. Discharge to the storm drain system from areas where repair of machinery and equipment, including motor vehicles, which are visibly leaking oil, fluids, or coolants is undertaken;

4. Discharge to the storm drain system from storage areas for materials containing grease, oil, or hazardous materials, or from uncovered receptacles containing hazardous materials, grease, or oil;

5. Discharge of commercial/public swimming pool filter backwash to the storm drain system;

6. Discharge from the washing of toxic materials from paved or unpaved areas to the storm drain system;

7. Discharge from the washing out of concrete trucks to the storm drain system; and

8. Discharge from the washing or rinsing of restaurant mats, equipment, or garbage bins or cans in such a manner that causes non-stormwater to enter the storm drain system.

B. Industrial/commercial facility sources required to obtain a NPDES permit. Any industrial or commercial facility required to have a NPDES permit shall retain on-site and, upon request, make immediately available to the director the following documents as evidence of compliance with permit requirements, as applicable:

1. A copy of a NPDES permit or notice of intent to comply with a general permit to discharge stormwater associated with industrial or construction activity as

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submitted to the State Board or report of waste discharge as submitted to a Regional Board of jurisdiction;

2. A waste discharge identification number issues by the State Board or copy of the NPDES permit issued by a Regional Board;

3. A SWPPP and a monitoring program plan or group monitoring plan;

4. Stormwater quality data;

5. Evidence of facility self-inspection; or

6. Evidence that facilities has filed a Notice of Non-Applicability (NONA) or any applicable waiver issued by the Los Angeles Water Board or State Water Board pertaining to stormwater discharges.

C. Best management practices for industrial and commercial facilities. All industrial and commercial facilities shall implement BMPs which will effectively prevent the direct or indirect discharge of pollutants to the storm drain system or receiving waters to the maximum extent practicable. Minimum BMPs applicable to all industrial and commercial facilities include, but are not limited to the following:

1. Termination of all non-stormwater discharge to the storm drain system that is not specifically authorized by a NPDES permit;

2. Exercising general good housekeeping practices;

3. Incorporating regular scheduled preventative maintenance into operations;

4. Maintaining spill prevention and control procedures;

5. Implementing soil erosion control;

6. Posting on-site private storm drains to indicate that they are not to receive liquid, solid wastes, or pollutants;

7. Implementing regular cleaning of the on-site private storm drain system;

8. Ensuring that stormwater runoff is directed away from operating, processing, fueling, cleaning and storage areas;

9. Remove trash, debris, and free-standing oil/grease, spill/leaks from sidewalks and hard surfaces; and

10. Sidewalk washing should be performed using high pressure, low-volume spray washing using only potable water with no cleaning agents at an average usage of

0.006 gallons per square feet of sidewalk area.

14.11.080 Low Impact Development Standards for New Development and Redevelopment.

14.11.050 Low Impact Development Standards for New Development and Redevelopment.

A. All Priority Development project, i.e., new development/redevelopment projects shall comply with the provisions of the City’s Low Impact Development Ordinance, Chapter

14.13. B. Failure to comply with an approved urban stormwater mitigation plan after receiving any required planning approval shall be a misdemeanor. (Ord. 1064 § 4, 1997)

14.11.090 Requirements for Construction Projects.

A. No person shall commence any construction activity for which a permit is required by this Chapter or any law or regulation without implementing stormwater and runoff pollution

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mitigation measures required by such permit(s), law, regulation or this Chapter. In addition, prior to obtaining a grading or building permit, each operator of any construction activity shall submit evident to the City Engineer that all applicable permits have been obtained, including but not limited to the General Construction Activities Storm Water Permit and State Water Board 401 Water Quality Certification.

B. No grading permit shall be issued for developments with disturbed areas of one (1) acre or greater or which is part of a larger common plan of development unless the applicant can show that:

1. A notice of intent (NOI) to comply with the state construction activity stormwater permit has been filed;

2. A stormwater pollution prevention plan (SWPPP) has been prepared; and

3. A post-construction plan meeting the low-impact development standards in Chapter

14.13 has been submitted.

C. Prior to obtaining a grading or building permit, each operator of a construction site less than one (1) acre shall prepare and submit to the City Engineer, a plan to: control erosion and sediment; prevent erosion, sediment loss, and the discharge of construction wastes.

D. The following minimum set of BMPs shall apply to all construction sites (regardless of size):

1. Site Management – housekeeping.

2. Erosion Controls – scheduling and preservation of existing vegetation.

3. Sediment Controls – perimeter controls and stabilized construction site entrance and exit.

4. Non-Stormwater Management – Water conservation practices and dewatering operations.

5. Waste Management – Material delivery and storage; stockpile management; solid waste management; concrete waste management; and sanitary/septic waste management.

E. The following minimum BMPs are required for both private or public roadway paving or repair operations:

1. Restrict paving and repaving activities to exclude periods of rainfall or predicted rainfall unless required by emergency conditions.

2. Install gravel bags and filter fabric or other equivalent inlet protection at all susceptible storm drain inlets and at manholes to prevent spills of paving products and tack coat.

3. Prevent the discharge of release of agents including soybean oil, other oils, or diesel to the asphalt.

4. Minimize non-stormwater runoff from water use for roller equipment and for evaporative cooling of the asphalt.

5. Clean equipment over absorbent pads, drip pans, plastic sheeting or other materials to capture all spillage and dispose properly.

6. Collect liquid waste in a container, with a secure lid, for transport to a maintenance facility to be reused, recycled or disposed of properly.

7. Collect solid waste by vacuuming or sweeping and securing in an appropriate container for transport to a maintenance facility to be reused, recycled or disposed of properly.

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8. Cover “cold-mix” asphalt with protective sheeting during a rainstorm.

9. Cover loads with tarp before haul-off to a storage site, and do not overload trucks.

10. Minimize airborne dust by using water spray or other approved dust suppressant during grinding.

11. Avoid stockpiling soil, sand, sediment, asphalt material, and asphalt grindings materials or rubble in or near stormwater drainage systems or receiving waters.

12. Protect stockpiles with a cover or sediment barriers during rain.

F. Project plans must include a narrative discussion of the reasons used for selecting or rejecting BMPs. In lieu of a narrative, the project architect or engineer of record may sign a statement on the plan to the following effect:
"As the architect/engineer of record, I have selected appropriate BMPs to effectively minimize the negative impacts of this project's construction activities on stormwater quality. The project owner and contractor are aware that the selected BMPs must be installed, monitored, and maintained to ensure their effectiveness. The BMPs not selected for implementation are redundant or deemed not applicable to the proposed construction activities." G. The requirements set forth in this Chapter shall apply at the time of demolition of an existing structure or commencement of construction and until the project receives final occupancy/clearance from the City.

14.11.100 Municipal Facility Activities.

A. Any municipal activity/facility required to have a NPDES permit shall prepare the following documents as evidence of compliance with permit requirements, as applicable:

1. A copy of an NPDES permit or NOI to comply with a general permit to discharge stormwater associated with industrial or construction activities as submitted to the State Water Resources Control Board or report of waste discharge submitted to the Los Angeles Regional Board;

2. A waste discharge identification number issued by the State Water Resources Control Board or copy of the NPDES permit issued by the Los Angeles Regional Board;

3. A SWPPP and a monitoring program plan or group monitoring plan;

4. Stormwater quality data;

5. Evidence of facility self-inspection; or

6. Evidence that the facility has filed a Notice of Non-Applicability (NONA) or applicable wavier issued by the Los Angeles Regional Board or State Water Resources Control Board pertaining to stormwater discharges.

B. Additionally, the City will implement stormwater BMPs that will address the following public agency areas:

1. Sewage systems operations;

2. Public construction activities management;

3. Vehicle maintenance/material storage facilities management;

4. Landscape and recreational facilities management;

5. Storm drain operation and management;

6. Streets and roads maintenance;

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7. Parking facilities management;

8. Public industrial activities;

9. Emergency procedures.

14.11.110 Public Information and Participation Program.

The City will continue to collaboratively with the East San Gabriel Valley Watershed Group and with County-wide and Region-wide partners to do the following:

1. Increase caused understanding about the importance of stormwater management to public health/community health, environmental quality and local water resiliency, and;

2. Increase support for stormwater management program and stormwater projects among the City’s residents and businesses.

14.11.120 Inspection and Fees.

A. Routine or Area Inspections. Whenever necessary to make an inspection to enforce any of the provisions of this Chapter, inspections shall be based upon such reasonable selection process as may be deemed necessary to carry out the objectives of this Chapter, including but not limited to, random sampling and/or sampling in areas with evidence of stormwater contamination, discharges of non-stormwater to the City 's storm drain system, discharges which are not pursuant to a NPDES permit, or similar factors.

B. Inspection for Reasonable Cause. Whenever an authorized enforcement officer has reasonable cause to believe that there exists in any building or upon any premises any condition which constitutes a violation of the provisions of this chapter, the officer may, upon consent or upon obtaining an inspection warrant, enter such building or premises at all reasonable times to inspect the same or perform any duty imposed upon the officer by this Chapter. The following actions may be carried out during such inspection:

1. Inspect, sample, make flow measurements of any runoff, discharge, or threatened discharge;

2. Place on the premises devices for runoff or discharge sampling, monitoring, flow measurement, or metering;

3. Inspect, copy, or examine any records, reports, plans, test results, or other information required to carry out the provisions of this Chapter, to the extent allowed by law; and

4. Photograph any materials, storage area, waste, waste containers, BMP(s), vehicle(s), connection, discharge, runoff, and/or violation discovered during an inspection.

C. Interference with an inspector is prohibited. No person shall, during reasonable hours, refuse, restrict, resist, or attempt to resist the entrance of the City’s inspector into any building, factory, plant, yard, construction site or portions thereof in the performance of his/her duty within the powers conferred upon them by law.

D. A fee that shall reimburse the City for the costs of inspections of facilities undertaken pursuant to this Chapter or any federal, state, regional and/or local regulatory agency order or permit pertaining to stormwater pollution or discharges shall be collected concurrently

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at the time of payment of the business license fee. The amount of the fee shall be established by City Council resolution and is intended to reimburse the City for the costs of inspections, and shall be imposed on those facilities where inspections occur. (Ord. 1139 § 1, 2003; Ord. 1064 § 4, 1997)

14.11.130 Enforcement and Penalties.

A. Except as otherwise provided in this Chapter, for the first failure to comply with any provision of this Chapter, the Director of Public Works, or his or her designee, may issue to the affected party a written notice that includes the following information

1. A statement specifying the violation committed and order to comply;

2. A specified time period within which the affected person shall correct the failure or file a written notice disputing the notice of violation;

3. A statement of the penalty for continued noncompliance.

B. Each subsequent failure to comply with any provision of this Chapter following written notice issued pursuant to subsection A of this section shall constitute a misdemeanor or an infraction punishable as provided in Chapter 1.12 of the San Dimas Municipal Code.

Each day during which a person fails to comply with the provisions of this Chapter following written notice shall constitute a separate offense.

C. A violation of any provision of this Chapter is declared to be a public nuisance and the City is authorized to abate such violation by means of a civil action. Additionally, the Director may summarily abate such nuisance upon determination that the nuisance constitutes an immediate threat to public health or safety.

D. The penalties and remedies established by this section shall be cumulative and shall include costs incurred by the City for such abatement, including reasonable attorney’s fees and other costs of enforcement. (Ord. 1064 § 4, 1997)

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14.11.140 Disclaimer of Liability.

The degree of protection required by this Chapter is considered reasonable for regulatory purposes and is based on scientific, engineering and other relevant technical considerations. The standards set forth herein are minimum standards and this Chapter does not imply that compliance will ensure that there will be no unauthorized discharge of pollutants into the waters of the United States. This Chapter shall not create liability on the part of the City, any officer or employee thereof, for any damages that result from reliance on this Chapter or any administrative decision lawfully made thereunder. (Ord. 1064 § 4, 1997)

14.11.150 Taking.

The provisions of this Chapter shall not operate to deprive any property owner of any constitutionally protected right. If a property owner claims that application of this Chapter to a specific project would deprive the property owner of a constitutionally protected right, then such property owner shall make application to the City, and the City may allow additional land uses, but only to the extent necessary to avoid depriving the property owner of a proven constitutionally protected right. In any such application the burden shall be on the property owner to demonstrate that strict application of this Chapter would cause the deprivation of a constitutionally protected right. Such additional land uses shall be consistent with and carry out the purposes of this Chapter as set forth herein, and shall not be inconsistent with any other federal, state, or local laws, including but not limited to the City’s General Plan. (Ord. 1064 § 4, 1997)

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SECTION II. Chapter 14.13 of the San Dimas Municipal Code is hereby amended to read, in its entirety, as follows:

San Dimas, California Municipal Code Title 14 WATER AND SEWERS Chapter 14.13 LOW IMPACT DEVELOPMENT

14.13.010 Title.

14.13.020 Purpose.

14.13.030 Findings.

14.13.040 Definitions.

14.13.050 New development and redevelopment project provisions applicability.

14.13.060 Project performance criteria.

14.13.070 Alternative compliance for technical infeasibility.

14.13.080 Hydromodification Management Requirements

14.13.090 Plan review procedures.

14.13.100 Plan review fees.

14.13.110 Maintenance agreement.

14.13.120 Enforcement.

14.13.130 Stop work order.

14.13.140 Failure to comply-Completion

14.13.150 Emergency measures.

14.13.160 Cost recovery for damage to storm drain system.

This chapter shall be known as the "City of San Dimas Low Impact Development (LID) Ordinance" and may be so cited. (Ord. 1231 § 1, 2014)

14.13.020 Purpose.

It is the purpose of this chapter to establish minimum stormwater management requirements and controls to accomplish, among others, the following objectives:

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A. Lessen the water quality impacts of development by using smart growth practices and integrate Low Impact Development (LID) design principles to mimic predevelopment hydrology through infiltration, evapotranspiration, and rainfall harvest and use.

B. Minimize the adverse impacts from stormwater runoff on the biological integrity of natural drainage systems and the beneficial uses of waterbodies.

C. Minimize the percentage of impervious surfaces on land developments by minimizing soil compaction during construction, designing projects to minimize the impervious area footprint, and employing Low Impact Development (LID) design principles.

D. Maintain existing riparian buffers and enhance riparian buffers when possible.

E. Minimize pollutant loadings from impervious surfaces such as roof tops, parking lots, and roadways through the use of properly designed, technically appropriate Best Management Practices (BMPs), including source control BMPs Standard Urban Stormwater Mitigation Plan [SUSMP] design standards, and treatment control BMPs).

F. Properly select, design, and maintain LID and hydromodification control BMPs to address pollutants that are likely to be generated, reduce changes to pre-development hydrology, assure long-term function, and avoid the breeding of vectors.

G. Prioritize the selection of BMPs to remove stormwater pollutants, reduce stormwater runoff volume, and beneficially use stormwater to support an integrated approach to protecting water quality and managing water resources in the following order of preference:

1. On-site infiltration, bioretention and/or rainfall harvest and use.

2. On-site biofiltration, off-site ground water replenishment, and/or off-site retrofit.

14.13.030 Findings.

The City of San Dimas (hereinafter referred to as “City”) finds the following:

A. Waterbodies, roadways, structures, and other property within and downstream of the City are at times subject to flooding.

B. Land development alters the hydrologic response of watersheds, resulting in increased stormwater runoff rates and volumes, increased flooding, increased stream channel erosion, increased sediment transport and deposition, and increased nonpoint source pollutant loading to the receiving waterbodies and the beaches.

C. Stormwater runoff produced by land development contributes to increased quantities of water-borne pollutants.

1. Increases of stormwater runoff, soil erosion, and non-point source pollution have occurred as a result of land development and have impacted the water resources of the San Gabriel River Watershed.

2. Increased stormwater runoff rates and volumes and the sediments and pollutants associated with stormwater runoff from future development projects within the City

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will, absent proper regulation and control, adversely affect the City's waterbodies and water resources, and those of downstream municipalities.

3. Stormwater runoff, soil erosion, and non-point source pollution can be controlled and minimized by the regulation of stormwater runoff from development.

4. Adopting the standards, criteria, and procedures contained in this chapter and implementing the same will address many of the deleterious effects of stormwater runoff. (Ord. 1231 § 1, 2014)

14.13.040 Definitions.

For purposes of this chapter, any term used in this chapter shall be defined as the term in the Los Angeles Regional Phase I Municipal Storm Water Permit, Order No. R4-2021-0105 (Permit), and any amendments revisions or reissuance thereof. Terms not specifically defined in this chapter shall have the meaning customarily assigned to them. The following words and phrases shall have the following meanings when used in this chapter:
“85th Percentile, 24-Hour Storm Event” is a statistical design storm defined through a hydrologic analysis of long-term rainfall records for a particular geographic area. At the most basic level, the design storm represents the 85th percentile, 24-hour rainfall depth (typically measured in inches of rain) among all 24-hour rainfall depths evaluated in the historical record. Analyses that define this storm event often express the 85th percentile, 24-hour storm event as an “isohyetal” or “isopluvial” map with contour lines connecting areas with the same 85th percentile 24-hour rainfall depth. In some situations (e.g., in storm hydrographs), the temporal distribution of rainfall during the 85th percentile, 24-hour storm event may be assumed. “Act or Clean Water Act (CWA)” means the Federal Water Pollution Control Act, also known as the Clean Water Act as amended 33 U.S.C. 1251, et seq.
“Applicant” means any person proposing or implementing the development of land. “Areas of Special Biological Significance (ASBS)” as defined in the Water Quality Control Plan for Ocean Waters of California (California Ocean Plan), ASBS are all those areas designated by the State Water Board as ocean areas requiring protection of species or biological communities to the extent that maintenance of natural water quality is assured. All Areas of Special Biological Significance are also classifies as a subset of State Water Quality Protections Areas. ASBS are also referred to as State Water Quality Protection Areas – Areas of Special Biological Significance (SWQPA-ASBS).
“Automotive Service Facility” means a facility that is categorized in any one of the following Standard Industrial Classification (SIC) and North American Industry Classification System (NACIS) codes (5013, 5014, 5511, 5541, 7532 -7534and 7536-7539). “Best Management Practice (BMP)” means practices or physical devices or systems designed to prevent or reduce pollutant loading from stormwater or non-stormwater discharges to receiving waters.
“Biofiltration” means a LID BMP that reduces stormwater pollutant discharges by intercepting rainfall on vegetative canopy, and through incidental infiltration and/or evapotranspiration, and filtration. Incidental infiltration is an important factor in achieving the required pollutant load reduction. Therefore, the term “biofiltration” as used in achieving the required pollutant load

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reduction. Therefore, the term “biofiltration” as used is defined to include only systems designed to facilitate incidental or achieve the equivalent pollutant reduction as biofiltration BMPs with an underdrain. Biofiltration BMPs include bioretention systems with an underdrain and bioswales. “Bioretention” means a LIP BMP that reduces stormwater runoff by intercepting rainfall on vegetative canopy, and through evapotranspiration and infiltration. The bioretention system typically includes a minimum 2-foot top layer of a specified soil and compost mixture underlain by a gravel-filled temporary storage pit dug into the in-situ soil. As defined in the Permit, a bioretention BMP may be designed with an overflow drain, but may not include an underdrain.

When a bioretention BMP is designed or constructed with an underdrain, it is regulated by the Permit as biofiltration.
“City” means the City of San Dimas.
“Clean Water Act (CWA)” means the Federal Water Pollution Control Act enacted in 1972, by Public Law 92-500, and amended by the Water Quality Act of 1987. The Clean Water Act prohibits the discharge of pollutants to Waters of the United States unless the discharge is in accordance with an NPDES permit.
“Commercial Malls” means any development on private land comprised of one or more buildings forming a complex of stores which sells various merchandise, with interconnecting walkways enabling visitors to easily walk from store-to-store, along with parking area(s). A commercial mall includes but is not limited to mini-malls, strip malls, other retail complexes, and enclosed shopping malls or shopping centers.
“Construction Activity” means any construction or demolition activity, clearing, grading, grubbing, or excavation or any other activity that result in land disturbance. Construction does not include emergency construction activities required to immediately protect the public health and safety of routine maintenance activities required to maintain the integrity of structures by performing minor repair and restoration work, maintain the original line and grade, hydraulic capacity, or original purposes of the facility.
“Design Engineer” means the registered professional engineer responsible for the design of the stormwater management plan.
“Development” means construction, rehabilitation, redevelopment, or reconstruction of any public or private residential project (whether single-family, multi-unit, or planned unit development); industrial, commercial, retail, and other non-residential projects, including public agency projects; or mass grading for future construction. It does not include routine maintenance to maintain original line and grade, hydraulic capacity, or original purpose of facility, nor does it include emergency construction activities required to immediately protect public health and safety. “Directly Adjacent” means situated within 200 feet of the contiguous zone required for the continued maintenance, function, and structural stability of the environmentally sensitive area. “Effective Impervious Area (EIA)” is the portion of the surface area that is hydrologically connected to a drainage system via a hardened conveyance or impervious surface without any intervening pervious area to mitigate the runoff volume.

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“Emergency Situation” means any incident, whether natural, technological, or human-caused, that requires responsive action to protect life or property (as defined by the Federal Emergency Management Agency). The responsive action should implement measures, to the fullest extent possible, to reduce the threat to water quality.
“Flow-through BMPs” means modular, vault type “high flow biotreatment” devices contained within an impervious vault with an underdrain or designed with an impervious liner and an underdrain. “General Construction Activities Storm Water Permit (GCASP)” means the general NPDES permit adopted by the State Board which authorizes the discharge of stormwater from construction activities under certain conditions.
“Green Roof “means a LID BMP using planter boxes and vegetation to intercept rainfall on the roof surface. Rainfall is intercepted by vegetation leaves and through evapotranspiration. Green roofs may be designed as either a bioretention BMP or as a biofiltration BMP. To receive credit as a bioretention BMP, the green roof system planting medium shall be of sufficient depth to provide capacity within the pore space volume to contain the design storm depth and may not be designed or constructed with an underdrain.
“Hydrologic Unit Code (HUC)” is standardized watershed classification system in which each hydrologic unit is identified by a unique hydrologic unit code (HUC). The HUC may consist of an eight (8) to twelve (12) digit number. The 8-digit HUC identifies an area based on four levels of classification: region, sub-region, hydrologic basin, and hydrologic sub-basin. The Watershed Boundary Dataset includes the 12-digit HUC delineation, which further divides each hydrologic unit into watersheds and sub-watersheds based on scientific information and not administrative boundaries.
“Hydromodification” means the alteration away from a natural state of stream flows or the beds or banks of rivers, streams, or creeks, including ephemeral washes, which results in hydrogeomorphic changes.
“Impervious Surface” means any man-made or modified surface that prevents or significantly reduces the entry of water into the underlying soil, resulting in runoff from the surface in greater quantities and/or at an increased rate, when compared to natural conditions prior to development.

Examples of places that commonly exhibit impervious surfaces include parking lots, driveways, roadways, storage areas, and rooftops. The imperviousness of these areas commonly results from paving, compacted gravel, compacted earth, and oiled earth. “Industrial Park” means land development that is set aside for industrial development. Industrial parks are usually located close to transport facilities, especially where more than one transport modalities coincide: highways, railroads, airports, and navigable rivers. It includes office parks, which have offices and light industry.
“Infiltration BMP” means a LID BMP that reduces stormwater runoff by capturing and infiltrating the runoff into in-situ soils or amended on-site soils. Examples of infiltration BMPs include infiltration basins, dry wells, and pervious pavement.
“LID” means Low Impact Development. LID consists of building and landscape features designed to retain or filter stormwater runoff.

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“Maintenance Agreement” means a binding agreement that sets forth the terms, measures, and conditions for the maintenance of post-construction BMP requirements, with exception of simple LID BMP’s implemented on single family residences.
“Natural Drainage System” means a drainage system that has not been improved (e.g., channelized or armored). The clearing or dredging of a natural drainage system does not cause the system to be classified as modified as defined in Hydromodification. “New Development” means land disturbing activities; structural development, including construction or installation of a building or structure, creation of impervious surfaces; and land subdivision.
“Parking Lot” means land area or facility for the parking or storage of motor vehicles used for businesses, commerce, industry, or personal use, with a lot size of 5,000 square feet or more of surface area.
“Plan” means written narratives, specifications, drawings, sketches, written standards, operating procedures, or any combination of these which contain information pursuant to this Chapter. “Planning Priority Projects” means development projects subject to Permittee conditioning and approval for the design and implementation of post-construction controls to mitigate stormwater pollution, prior to completion of the project(s).
“Rainfall Harvest and Use” means a LID BMP system designed to capture runoff, typically from a roof but can also include runoff capture from elsewhere within the site, and to provide for temporary storage until the harvested water can be used for irrigation or non-potable uses. The harvested water may also be used for potable water uses if the system includes disinfection treatment and is approved for such use by the local building department. “Receiving Water” means “water of the United States” into which waste and/or pollutants are or may be discharged.
“Redevelopment” includes but is not limited to the following: the expansion of a building footprint; addition or replacement of a structure; replacement of impervious surface area that is not part of a routine maintenance activity; and land disturbing activities related to structural or impervious surfaces. It does not include routine maintenance to maintain original line and grade, hydraulic capacity, or original purpose of facility, nor does it include emergency construction activities required to immediately protect public health and safety. “Restaurant Establishments” means businesses primarily engaged in the retail sale of prepared food and drinks for on-premise or immediate consumption. Caterers and industrial and institutional food service establishments are also included in this industry (SIC Code 5812). “Retail Gasoline Outlet” means any facility engaged in selling gasoline and lubricating oils – SIC 5541 and NAICS 447110 and 447190.
“Retention” means a holding system for stormwater, either natural or man-made, which does not have an outlet to adjoining watercourses or wetlands and in which water is removed through infiltration and/or evaporation processes.

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“Routine Maintenance Projects” include, but are not limited to projects conducted to the following:

1. Maintain the original line and grade, hydraulic capacity, or original purpose of the facility.

2. Perform as needed the restoration work to preserve the original design grade, integrity, and hydraulic capacity of flood control facilities.

3. Includes road shoulder work, re-grading dirt or gravel roadways and shoulders and performing ditch cleanouts.

4. Upgrade existing lines* and facilities to comply with applicable codes, standards, and regulations regardless if such projects result in increased capacity.

5. Repair leaks.

6. Routine maintenance does not include construction of new** lines or facilities resulting from compliance with applicable codes, standards, and regulations.

Note: * Update existing lines includes replacing existing lines with new materials or pipes. ** New lines are those that are not associated with existing facilities and are not part of a project to update or replace existing lines.
“Runoff” means any runoff including stormwater and non-stormwater from a drainage area that reaches a receiving water body.
“Significant Ecological Area (SEA)” means an area that is determined to possess an example of biotic resources that cumulatively represent biological diversity for the purpose of protecting biotic diversity as part of the Los Angeles County General Plan.

Single-family hillside home means, one acre or greater property located in an area with known erosive soil conditions, where the development contemplates grading on any natural slope that is 25% or greater and where grading, contemplates cut or fill slopes. “Site” means land or water area where any “facility or activity” is physically located or conducted, including adjacent land used in connection with the facility or activity. “Source Control BMP” means any schedules of activities, prohibitions of practices, maintenance procedures, managerial practices, or operational practices that aim to prevent stormwater pollution by reducing the potential for contamination at the source of pollution. “Storm Drain System” means any facilities or any part of those facilities, including streets, gutters, conduits, natural or artificial drains, channels, and watercourses that are used for the purpose of collecting, storing, transporting, or disposing of stormwater and are located within the City of San Dimas.
“Storm Water or Stormwater” means water that originates from atmospheric moisture (rain or snow) and that falls onto land, water, or other surfaces. Without any change in its meaning, this term may be spelled or written as one word or two separate words. “Stormwater Quality Design Volume (SWQDv)” means the runoff from a. The 0.75-inch, 24-hour rain event; or
b. The 85th percentile, 24-hour rain event as determined from the Los Angeles County 85th percentile precipitation isohytal map, whichever is greater.

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“Stormwater Runoff” means that part of precipitation (rainfall or snowmelt) which travels across a surface to the storm drain system or receiving waters.
“SUSMP” means the Los Angeles Countywide Standard Urban Stormwater Mitigation Plan. The SUSMP was required as part of the previous Municipal NPDES Permit (Order No. 01-182, NPDES No. CAS004001) and required plans that designate best management practices (BMPs) that must be used in specified categories of development projects. “Treatment Control BMP” means any engineered system designed to remove pollutants by simple gravity settling of particulate pollutants, filtration, biological uptake, media absorption or any other physical, biological, or chemical process. (Ord. 1231 § 1, 2014)

14.13.050 Development and Redevelopment Project Provisions Applicability These procedures and standards set forth in this chapter apply to Priority Development Projects that fall under the City’s planning and building authority for which specific requirements, including the implementation of structural BMPs meeting the performance requirements of the Los Angeles Regional Phase I Municipal Storm Water Permit Order No, 2021-0105 (Order) and all amendment, revisions, or reissuance thereof. The standards set forth in Order minimum standards to be complied with by developers and in no way limit the authority of the City of San Dimas to adopt or publish and/or enforce higher standards as a condition of approval of developments.

A. Priority Development Projects include the following:

1. New Development Projects within any of the following categories or meeting the following criteria:
a. All development projects equal to one acre or greater of disturbed area and adding more than ten thousand (10,000) square feet of impervious surface area (collectively over the entire project site).
b. Industrial parks ten thousand (10,000) square feet or more of surface area. c. Commercial malls ten thousand (10,000) square feet or more of surface area.

2. Redevelopment projects that create and/or replace five thousand (5,000) square feet or more of impervious surface (collectively over the entire project site) on any of the following:
a. Existing site of ten thousand (10,000) square feet or more impervious surface area;
b. Industrial parks ten thousand (10,000) square feet or more impervious surface area; or
c. Commercial malls ten thousand (10,000) square feet or more impervious surface area.

3. New development and redevelopment projects that create and/or replace five thousand (5,000) square feet or more impervious surface (collectively) over the entire project site) and support one or more of the following uses:
a. Restaurants

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b. Parking lots
c. Automotive service facilities (standard industrial classifications [SIC] 5013, 5014, 5511, 7532-7534, and 7536-7539)
d. Retail gasoline outlets

4. New development and redevelopment projects that create and/or replace twentyfive (2,500_ square feet or more of impervious area that are likely to impact a sensitive biological species or habitat; and are located or directly adjacent to an Area of Special Biological Significance or Sensitive Ecological Area (SEA) such as San Dimas Canyon/San Antonio Wash.

5. Street and road construction of ten thousand (10,000) square feet or more of impervious surface area shall follow the City of San Dimas Green Streets Policy to the maximum extent practicable. Street and road construction applies to streets, roads, highways, and freeway projects, and streets within larger projects.

6. Redevelopment projects meeting the redevelopment thresholds that result in the alteration to more than fifty percent (50%) of impervious surfaces of a previously existing development, shall address the entire project.

7. Redevelopment projects meeting the redevelopment thresholds that result in the alteration to less than fifty percent (50%) of impervious surfaces of a previously existing development, only the alteration must be mitigated, not the entire project site.

8. Single-Family Hillside Homes. During the construction of a single-family hillside home, the following measures shall be considered to the maximum extent practicable:
a. Conserve natural areas.
b. Protect slopes and channels.
c. Provide storm drain system stenciling and signage.
d. Divert roof runoff to vegetated areas before discharge unless the diversion would result in slope instability.
e. Direct surface flow to vegetated areas before discharge unless the diversion would result in slope instability.

B. Redevelopment Projects. Redevelopment projects subject to conditioning and approval requirements outlined in this chapter for the design and implementation of postconstruction controls to mitigate stormwater pollution prior to completion of the project(s) include the following:

1. Redevelopment projects that result in an alteration to more than fifty percent (50%) of impervious surfaces of an existing development which had not been not subject to post-construction stormwater quality control requirements at the time of the previous development shall be required to mitigate the entire project site.

2. Redevelopment projects that result in an alteration to more than fifty percent (50%) of impervious surfaces of an existing development which had not been not subject to post-construction stormwater quality control requirements at the time of the previous development shall be required to mitigate the entire project site.

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3. Redevelopment does not include routine maintenance activities that are conducted to maintain original line and grade, hydraulic capacity, original purpose of facility or emergency redevelopment activity required to protect public health and safety.

Impervious surface replacement, such as the reconstruction of parking lots and roadways, which does not disturb additional area and maintains the original grade and alignment, is not considered a routine maintenance activity. Redevelopment does not include the repaving of existing roads to maintain original line and grade.

4. Existing single-family dwelling and accessory structures are exempt from the redevelopment requirements unless such projects create, add, or replace ten thousand square feet of impervious area. (Ord. 1231 §, 2014)

14.13.060 Project Performance Criteria.

All development projects that fit the project criteria listed in Section 14.13.050 of this chapter shall control pollutants, pollutant loads, and runoff volume by retaining the stormwater quality design (SWQDv) on-site through the following:

1. On-site infiltration, bioretention and/or rainfall harvest and use;

2. If subpart A above is infeasible, on-site biofiltration, offsite groundwater replenishment and/or off-site retrofit; or

3. If subpart B above is infeasible, on-site treatment is required, where all the above options are infeasible. Ord.1231 § 1, 2014)

14.13.070 Alternative Compliance for Technical Infeasibility.

To demonstrate technical infeasibility, the project applicant shall demonstrate to the City Engineer that the project cannot reliably retain one hundred percent of the SWQDv on-site, even with the maximum application of green roofs and rainwater harvest and use, and that compliance with the application post-construction requirements would be technically infeasible. This shall be demonstrated by submitting a site-specific hydrologic and/or design analysis conducted and endorsed by a registered professional engineer, geologist, architect, and/or landscape architect and shall be subject to review and approval by the City Engineer.

When evaluating the potential on-site retention, each applicant shall consider the maximum potential for evapotranspiration from green roofs and rainfall harvest and use.

If partial or complete on-site retention is technically infeasible, the project applicant shall consider the following alternative compliance measures.

A. On-Site Biofiltration. Biofiltration systems shall meet the design specifications provided in the Los Angeles County LID Manual (2014 and its revisions), or reissuance thereof equivalent LID manual. If using biofiltration due to demonstrated technical infeasibility, project must biofiltrate 1.5 times the portion of the SWQDv that is not reliably retained onsite, as calculated by Equation 1 below:

Equation 1:

Bv = 1.5 x [SWQDv - Rv]

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Where:

Bv = biofiltration volume.

SWQDv = the stormwater runoff from a 0.75 inch, twenty-four-hour storm or the eightyfifth percentile storm, whichever is greater.

Rv = volume reliably retained on-site.

Biofiltration systems discharging to a receiving water that is included on the Clean Water Act section 303(d) list of water quality impairments due to nitrogen compounds, shall be designed and maintained to achieve enhanced nitrogen removal capacity.

B. Off-Site Infiltration. An applicant may use infiltration or bioretention BMPs to intercept a volume of stormwater runoff equal to the SWQDv, less the volume of stormwater runoff reliably retained on-site, at an approved off-site project located within the same subwatershed (HUC-12) as the Priority Development Project, and shall provide pollutant reduction (i.e., treatment) of stormwater runoff from the project site. The required off-site mitigation volume shall be calculated by Equation 2 below:

Equation 2:

Mv = 1.0 x [SWQDv - Rv]
Where:

Mv = mitigation volume.

SWQDv = runoff from the 0.75-inch, twenty-four-hour storm event or the eighty-fifth percentile storm, whichever is greater.

Rv = the volume of stormwater runoff reliably retained on-site.

C. Onsite Flow-based BMPs. If onsite biofiltration and off-site alternative compliance measures are not technically feasible, the applicant may request authorization by the City Engineer to allow the use of onsite flow-based BMPs. The applicant shall document why none of the other alternative compliance measures are feasible. Approval will only be granted to areas where other alternative compliance measures are not feasible due to significant technical issues. If approved the Flow-based treatment control BMPs must be sized and designed to do the following:

A. Filter or treat either:

1. The maximum flow rate of runoff produced from a rainfall intensity if 0.2 inch of rainfall per hour, for each hour of a storm event; or

2. The maximum flow rate of runoff produced by the 85th percentile hourly rainfall intensity (for each hour of a storm event), as determined from the local historical rainfall record, multiplied by a factor of two.

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B. Be certified for Enhanced Treatment under the Washington State Department of Ecology’s TAPE Program; or an appropriate future BMP certification developed by the State of California.

D. Off-Site Project-Retrofit Existing Development. Use infiltration, bioretention, rainfall harvest and use and/or biofiltration BMPs to retrofit an existing development, with similar land uses as the new development or land uses associated with comparable or higher stormwater runoff event mean concentrations (EMCs) than the new development. The retrofit plan shall be designed and constructed as described in the Los Angeles County Municipal Regional Storm Water Permit Order No. R4-2021-0105, and any amendments, revisions, or reissuance thereof.

E. Groundwater Replenishment. Regional projects to replenish regional groundwater supplies at an off-site location, provided the groundwater supply has a designed beneficial use, in accordance with – compliance performance standards detailed in the Los Angeles Regional Storm Water Permit Order No. R4 2021- 0105, and any amendments, revisions, or reissuance thereof.

Projects approved for off-site mitigation or ground water replenishment shall also provide treatment of stormwater runoff from the project site. Project applicant shall design and implement post-construction stormwater BMPs and control measures to reduce pollutant loading as necessary to ensure that the controls implemented on the site are designed so that stormwater discharges do not cause or contribute to exceedances of receiving water standards. (Ord. 1231 § 1, 2014)

14.13.080 Hydromodification Management Requirements.

Planning Priority Projects located within natural drainage systems shall implement hydrological control measures to prevent accelerated downstream erosion and protect stream habitat.

A. Natural drainage systems that are subject to the hydromodification assessments and control include all drainages that have not been modified using engineering controls or drainages that are tributary to a natural drainage system. Examples of engineering modifications to drainage include channelization, armoring with concrete, and application of rip-rap.

B. At the City’s discretion the following New Development and Redevelopment projects may be exempted from implementation of hydromodification controls where it has been documented that adverse hydromodification effects to Natural Drainage Systems are unlikely:

1. Projects consisting of replacement, maintenance, or repair of an existing flood control facility, storm drain, or transportation network.

2. Redevelopment Projects in the urban core that do not increase the effective impervious area or decrease the infiltration capacity of previous areas compared to pre-project conditions.

3. Projects that have any increased discharge directly via a storm drain to a sump, lake, into a waterway that has a 100-year peak flow (Q100) of 25,000 cubic feet per second or more, or other receiving water that is not susceptible to hydromodification impacts.

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4. Projects that discharge directly or via a storm drain into concrete or otherwise engineered channels which in turn, discharge into a receiving water that is not susceptible to hydromodification impacts.

5. LID BMPs implemented on single-family homes are sufficient to comply with the hydromodification criteria.

C. Projects disturbing an area less than or equal to 1 acre shall implement the applicable LID performance standards in subchapters 14.13.060 and/or 14.13.070.

D. Projects disturbing an area greater than 1 acre, but less than 50 acres will be presumed to meet pre-development hydrology if one of the following demonstrations are made:

The project is designed to retain on-site the runoff of the 95th percentile 24-hour storm; or

1. The runoff flow rate, volume, velocity, and duration of the post-development condition does not exceed the pre-development condition for the 2-year, 24- hour storm event; or

2. The Erosion Potential (Ep) in the receiving water is approximately 1. Ep shall be determined in accordance with the NPDES permit.

E. Projects disturbing 50 acres or more will be presumed to meet pre-development hydrology based on the successful demonstration of one of the following conditions:

1. The project site infiltrates on-site runoff from a 2-year, 24-hour storm event; or

2. The runoff flow rate, volume, velocity, and duration for the post-development condition does not exceed the pre-development condition for the 2-year, 24- hour storm event. These conditions must be substantiated by hydrologic modeling.

14.13. 090 Plan Review Procedures.

All stormwater plans shall be subject to review and approval by the City Engineer.

A. If the proposed plan is not sufficient as originally submitted, the City Engineer, or designee, will notify the applicant in writing, setting forth the reasons for withholding and will state the changes necessary to obtain approval.

B. If staff determines that all the required information has not been received, the applicant may request that the matter be tabled to allow for the submittal of the required information.

C. If all the required information has been received, staff shall approve, approve with conditions, or recommend denial of the stormwater plan, including waiver submissions.

Recommendations for action on the stormwater plan can be part of the recommendation for action on the site plan or subdivision plat.

D. If the plan is approved, the City will require the following:

1. The applicant shall provide copies of all necessary state, federal, or local permits relating to stormwater management to the City.

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2. A satisfactory maintenance covenant agreement that assures long-term maintenance of all drainage improvements shall be submitted as part of the final plan. The maintenance covenant shall include a listing of the BMPs and their location; an operation and maintenance plan; monitoring plan (where required); and verification of ongoing maintenance provisions for LID BMPs. The property owner shall be required to document proper maintenance and operations and maintain such records for a period of two years. Maintenance agreements and records shall be provided upon request to the City inspector at any time for compliance verification. Failure to do so will result in enforcement actions per the City code. The approved covenant shall be recorded with the Los Angeles County recorder prior to issuance of occupancy.

3. A satisfactory maintenance covenant shall at a minimum include the developer's signed statement accepting responsibility for maintenance until the responsibility is legally transferred, and either:
a. A signed statement from the public entity assuming responsibility for BMP maintenance; or
b. Written conditions in the sales or lease agreement, which require the property owner or tenant to assume responsibility for BMP maintenance and conduct a maintenance inspection at least once a year; or c. Written text in project covenants, conditions, and restrictions (CCRs) for residential properties assigning BMP maintenance responsibilities to the homeowners’ association; or
d. The applicant shall post cash or a letter of credit in an amount not less than one hundred percent of the cost of the stormwater facilities. This deposit shall be held for two years after the date of completion of construction and final inspection of the stormwater facilities, until accepted by the City. The percentage cost for cash or letter of credit may be reduced to ten percent for projects longer than two years.

4. This deposit shall be returned to the applicant (in the case of cash) or allowed to expire (in the case of a letter of credit), as provided above, provided all stormwater facilities are clean, unobstructed, and in good working order, as determined by the City Engineer.

5. Reproducible mylars and electronic files (in AutoCAD format) of the as-built storm drains and stormwater BMPs shall be submitted by the applicant or his/her engineer to the City along with the final plan, or upon completion of system construction. The mylars are to be of quality material and three mils in thickness. Complete development agreements (including deed restrictions) must be submitted for the City’s review and approval prior to recording. (Ord. 1231 § 1, 2014)

14.13.100 Plan Review Fees.

Fees and escrow account payments shall be sufficient to cover administrative and technical review costs anticipated to be incurred by the City of San Dimas including the costs of on-site inspections, as set forth by resolution of the City council. (Ord. 1231 § 1, 2014)

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14.13.110 Maintenance Agreement.

A. Purpose of Maintenance Agreement. The purpose of the maintenance agreement is to provide the means and assurance that maintenance of stormwater BMPs shall be undertaken. As a condition for issuing a certificate of occupancy for a new development or redevelopment project, the applicant, facility operator(s), and/or owner(s), as appropriate, shall construct and/or employ all stormwater control BMPs identified in the approved LID Plan; and submit a signed certification statement that the project site and all BMPs will be employed and maintained in compliance with the City’s LID ordinance and other applicable regulatory requirements until the responsibility for such maintenance is legally transferred to another party.

B. Maintenance Agreement Required. A maintenance agreement shall be submitted to the City for review by the City Engineer and/or designee and, if necessary, City attorney. The designers may select any combination of stormwater BMPs which meet the performance standards provided this selection and identified in the Order and any amendment, revision, or reissuance thereof. A formal maintenance and inspection plan shall be included in the maintenance agreement.

C. Maintenance Agreement Provisions.

1. The maintenance agreement shall include a plan for routine, emergency, and long-term maintenance of all stormwater BMPs, with a detailed annual estimated budget for the initial two years, and a clear statement that only future maintenance activities in accordance with the maintenance agreement plan shall be permitted without the necessity of securing new permits. Written notice of the intent to proceed with maintenance shall be provided by the party responsible for maintenance to the City of San Dimas at least fourteen (14) days in advance of commencing work.

2. The maintenance agreement shall be binding on all subsequent owners of land served by the stormwater BMPs. A copy of the operation and maintenance plan shall be kept on-site for periodic review by the City’s inspectors.

3. If it has been found by the City, following notice and an opportunity to be heard by the property owner, that there has been a material failure or refusal to undertake maintenance as required under this chapter and/or as required in the approved maintenance agreement as required hereunder, the City shall abate such violations, as a public nuisance, pursuant to the procedures set forth in Chapter 8.16 of the San Dimas Municipal Code.

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b. Types of BMPs (i.e., site design, source control and/or treatment control) to ensure modifications to the site are not conducted without the property owner being aware of the ramifications to BMP implementation. c. Clear depiction of location of BMPs, especially those located below ground. d. A matrix depicting the types of BMPs, frequency of inspection, type of maintenance required, and if proprietary BMPs, the company information to perform the necessary maintenance.
e. Agreement to retain documentation of proper maintenance for a period of two years.
f. Understanding that documentation of proper maintenance must be presented to the City upon request. (Ord. 1231 § 1, 2014)

5. The owners of the land served by the stormwater BMPs shall certify annually that all BMPs identified in the approved LID Plan have been inspected and maintained in accordance with the approved BMP maintenance plan. This certification shall be submitted to the City Engineer by September 30th annually.

6. The City of San Dimas shall inspect new development/redevelopment projects once every two (2) years after the date of project completion, to assess operational conditions for LID and hydromodification control BMP repair, replacement, and/or revegetation.

14.13.120 Enforcement.

Any person violating any provision of this chapter shall be responsible for a municipal civil infraction and subject to the City’s enforcement policy as set forth in the provisions of Title 1 and/or Chapter 8.16 of the San Dimas Municipal Code. (Ord. 1231 § 1, 2014)

14.13.130 Stop Work Order.

Where there is work in progress that causes or constitutes, in whole or in part, a violation of any provision of this chapter, the City is authorized to issue a stop work order to prevent further or continuing violations or adverse effects. All persons to whom the stop work order is directed, or who are involved in any way with the work or matter described in the stop work order shall fully and promptly comply therewith. The City may also undertake or cause to be undertaken, any necessary or advisable protective measures to prevent violations of this chapter or to avoid or reduce the effects of noncompliance herewith. The cost of any such protective measures shall be the responsibility of the owner of the property upon which the work is being done and the responsibility of any person carrying out or participating in the work. (Ord. 1231 § 1, 2014)

14.13.140 Failure to comply.

In addition to any other remedies, should any property owner fail to comply with the provisions of this chapter, the City may, after the giving of reasonable notice and opportunity for compliance, have the necessary work done, and the owner shall be obligated to promptly reimburse the City for all costs of such work. (Ord. 1231 § 1, 2014)

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June 25, 2024

14.13.150 Emergency Measures.

When emergency measures are necessary to moderate a nuisance, to protect public safety, health and welfare, and/or to prevent loss of life, injury or damage to property, the City is authorized to carry out or arrange for all such emergency measures. Property owners shall be responsible for the cost of such measures made necessary as a result of a violation of this chapter, and shall promptly reimburse the City for all such costs. (Ord. 1231 § 1, 2014)

14.13.160 Cost Recovery for Damage to Storm Drain System.

A discharger shall be liable for all costs incurred by the City as the result of causing a discharge that produces a deposit or obstruction, or causes damage to, or impairs a storm drain, or violates any of the provisions of this chapter. Costs include, but are not limited to, those penalties levied by the Environmental Protection Agency or Los Angeles Regional Water Quality Control Board for violation of an NPDES permit, attorney fees, and other costs and expenses. (Ord. 1231 § 1, 2014)
SECTION III. SEVERABILITY. If any section, subsection, subdivision, sentence, clause, phrase, or portion of this Ordinance is, for any reason, held to be invalid or unconstitutional by the decision of any court of competent jurisdiction, such decision shall not affect the validity of the remaining portions of this Ordinance. The City Council hereby declares that it would have adopted this Ordinance and each section, subsection, subdivision, sentence, clause, phrase, or portion thereof, irrespective of the fact that any one or more section, subsection, subdivision, sentence, clause, phrase, or portion thereof be declared invalid or unconstitutional.

SECTION IV. CEQA DETERMINATION. The City Council finds that the adoption of this Ordinance amending the Municipal Code is exempt from the requirements of the California Environmental Quality Act ( CEQA) on the basis that ( 1) State CEQA Guidelines sections 15307 and 15308 each categorically exempt the proposed adoption of the Ordinance since it is an action taken to protect natural resources and/or the environment ( specifically, water quality within the watershed under the jurisdiction of the Los Angeles Regional Water Quality Control Board), and environmental considerations have been accounted for' insofar as the entirety of the proposed Ordinance is environmentally beneficial and would have no indirect adverse environmental effects; and ( 2) the proposed Ordinance is not a " project" pursuant to CEQA since it can be seen with certainty that no adverse effect on the physical environment would occur pursuant to the proposed Ordinance since the only effects on the environment would be to improve water quality in stormwater channel discharges, and these effects are beneficial, and not adverse ( see State CEQA Guidelines section 15061( b)( 3)). City staff is directed to file a Notice of Exemption with the County Clerk within five (5) working days of the adoption of this Ordinance.

SECTION V. EFFECTIVE DATE AND PUBLICATION. This Ordinance shall take effect 30 days after its final passage. The City Clerk shall certify to the adoption of this Ordinance and cause the same to be posted as may be required by law.

PASSED, APPROVED AND ADOPTED at a regular meeting of the City Council of the City of San Dimas this 9th day of July, 2024, by the following vote:

AYES:

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June 25, 2024
NOES:

ABSENT:

ABSTAIN:
__________________________________
Emmett G. Badar, Mayor
ATTEST: APPROVED AS TO FORM:
__________________________ ___________________________
Debra Black, City Clerk Jeff Malawy, City Attorney
I, DEBRA BLACK, CITY CLERK of the City of San Dimas, do hereby certify that Ordinance 1306 was introduced at a regular meeting of the City Council of the City of San Dimas on the 25th day of June, 2024, and thereafter passed, approved and adopted at a regular meeting of said City Council held on the 9th day of July, 2024.
___________________________
Debra Black, City Clerk

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ATTACHMENT 2
*New text changes are in Blue and Underlined
Replaced Text is Red and Strikethrough
SECTION I. Chapter 14.11 of the San Dimas Municipal Code is hereby amended to read, in its entirety, as follows:

San Dimas, California Municipal Code Title 14 WATER AND SEWERS Chapter 14.11 STORMWATER MANAGEMENT AND DISCHARGE

14.11.010 Definitions.

14.11.020 Responsibility for administrationAdministration.

14.11.030 General Provisions.

14.11.030040 Prohibited Discharges andactivitiesActivities.

14.11.040050 Requirements for Existing Properties.Prohibited Connections to the MS4.

14.11.050060 Urban stormwater mitigation plan for new developmentsRequirements for Existing Properties.

14.11.060070 Requirements for construction projects.Requirements for Industrial and Commercial Facilities.

14.11.070080 Public agency activities.Low Impact Development Standards for New Development and Redevelopment.

14.11.090 Requirements for Construction Projects.

14.11.080100 Public information and participation programMunicipal Facility Activities.

14.11.090110 Inspection and fees.Public Information and Participation Program.

14.11.100120 Penalties for failure to comply.Inspections and Fees.

14.11.110130 Disclaimerofliability.Enforcement and Penalties.

14.11.140 Disclaimer of Liability.

14.11.120150 Taking.

14.11.010 Definitions.

In addition to the Glossary of Terms found in Attachment D to the Los Angeles County Municipal Storm Water Permit Order No. 96-054R4-2021-0105, the following words and phrases shall have the following specific meanings:

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2 “Adverse Impact” means any detrimental effect upon water quality or beneficial uses caused by a discharge of loading of a pollutant or pollutants. “Area susceptible to runoff” means any surface directly exposed to precipitation or in the path of runoff caused by precipitation that leads directly to neighboring properties or to the street.
“Areas of Special Biological Significance” means all those areas designated by the State Water Board as ocean areas requiring protection of species or biological communities to the extent that maintenance of natural water quality is assured. All Areas of Special Biological Significance are also classified as a subset of State Water Quality Protection Areas.
"Authorized enforcement officer'' means the cCity's code enforcement officer and the directorDirector of publicPublic worksWorks, including any person so designated by the directorDirector of publicPublic worksWorks.
“Authorized Non-Stormwater Discharge” means discharges that are not composed entirely of stormwater and that are either: (1) separately regulated by an Industrial or General NPDES permit and allowed to be discharges into the MS4 when in compliance with all NPDES permit conditions; (2) separately regulated by a conditional waiver of water discharge requirements (WDRs) or WDRs for agricultural lands; (3) authorized by U.S. EPA pursuant to sections 104(a) or 104(b) of Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) that either (i) will comply with water quality standards as applicable or relevant and appropriate requirements (ARARs) under section 121(d)(2) of CERCLA; or (ii) are subject to (a) a written waiver of ARARs by U.S. EPA pursuant to section 121(d)(4) of CERCLA or (b) a written determination by U.S EPA that compliance with ARARs is not practicable considering the exigencies of the situation, pursuant to 40 CFR section 300.415(j); or (4) necessary for emergency response purposes, including discharges from emergency firefighting activities.
“Automotive Service Facility” means a facility that is categorized by any one of the following Standard Industrial Classification (SIC) and North American Industry Classification System (NAICS) codes. For inspection purposes, facilities with SIC codes 5013, 5014, 5511, and 5541, will not be subject to inspection provided that these facilities have no outside activities or materials that may be exposed to stormwater.

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3 7538 811111
7539 811198 and 811118
"Best management practices" ("BMPs") means stormwater pollution control practices applicable to existing properties that significantly reduce and control stormwater runoff and prevent nonstrormwater runoff pollution from entering the storm drain system and the Pacific Ocean.practices or physical devices or systems designed to prevent or reduce pollutant loading from stormwater or non-stormwater discharges to receiving waters.
"City" means the cityCity of San Dimas.
"Code" means the San Dimas Municipal Code.
“Conditionally Exempt Non-Stormwater Discharge” means certain categories of discharges that are not composed entirely of stormwater and that are allowed by the Los Angeles Water Board to discharge into the MS4, if the discharge is in compliance with all specified requirements; are not otherwise regulated by an individual or general NPDES permit; and are essential public services that are directly or indirectly required by other State or federal statute and/or regulation.

These include non-stormwater discharges such as from drinking water supplier distribution system releases. Conditionally exempt essential non-stormwater discharges may contain minimal amounts of pollutants, however, when in compliance with industry standard BMPs and control measures, do not result in significant environmental effects.
“Construction Activity” means any construction or demolition activity, clearing, grading, grubbing, or excavation or any other activity that result in land disturbance.

Construction does not include emergency construction activities required to immediately protect public health and safety or routine maintenance activities required to maintain the integrity of structures by performing minor repair and restoration work, maintain the original line and grade, hydraulic capacity, or original purposes of the facility. See “Routine Maintenance” definition for further explanation. Where clearing, grading, or excavating of underlying soil takes place during a repaving operation, State General Construction Permit coverage by the State of California General Permit for Storm Water Discharges Associated with Industrial Activities or for Stormwater Discharges Associated with Construction Activities is required if more than one acre is disturbed or the activities are part of a larger plan. “Construction General Permit” means General Permit for Storm Water Discharges Associated with Construction and Land Disturbance Activities. General NPDES permit issued by the State Water Board, which authorizes the discharge of stormwater from construction activities under certain conditions. “Control” means to minimize, reduce, eliminate, or prohibit by technological, legal, contractual or other means, the discharge of pollutants from an activity or activities.

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4 “Dechlorinated/Debrominated Swimming Pool Discharge” means swimming pool discharges with do not contain measurable quantities of chlorine or bromine and do not contain any detergents, wastes, or additional chemicals not typically found in swimming pool water. The term does not include swimming pool filter backwash.
"Discharge" means any release, spill, leak, pump, flow, escape, dumping, or disposal of any liquid, semi-solid, or solid substancewithout qualification the release or a pollutant or pollutants to the MS4.
"Disturbed area" means an area altered as a result of clearing, grading and/or excavation of earth.
“Drinking Water Distribution System Discharges” means sources of flows from drinking water storage, supply, and distribution systems including flows from system failures, pressure releases, system maintenance, distribution line testing, fire hydrant flow testing; and flushing and dewatering of pipes, reservoirs, vaults, and minor noninvasive well maintenance activities not involving chemical addition(s). It does not include wastewater discharges from activities that occur at wellheads, such as well construction, well development (i.e., aquifer pumping tests, well purging, etc.), or major well maintenance.
“Emergency Situation” means any incident, whether natural, technological, or humancaused, that requires responsive action to protect life of property. "Gray water" means water that is discharged from sinks, showers, tubs, washing machines, dishwashers, and garbage disposals.
"Hazardous waste" means any material defined as hazardous by Chapter 6.95 of the California Health and Safety Code and any substance designated pursuant to 40 CFR 302. This includes unlisted hazardous substances that are solid wastes, as defined in 40 CFR 261.2, that are not excluded from regulation as hazardous wastes under 40 CFR 261.4(b) if they exhibit any of the characteristics identified in 40 CFR 261.20 through 261.24.
"Illicit connection" means any device that is connected to the storm drain system that conveys an illicit discharge. man-made conveyance that is connected to the storm drain system without a permit, excluding roof drains and other similar type connections. Examples include channels, pipelines, conduits, inlets, or outlets that are connected directly to the storm drain system.
"Illicit discharge" means any discharge into the MS4 that is prohibited under local, state, or federal statues, ordinances, codes, or regulations. The term illicit discharge includes any non-stormwater discharge, except those authorized non-stormwater discharges; conditionally exempt non-stormwater discharges; and non-stormwater discharges resulting from natural flows specifically identified in this Chapter. discharge onto the storm drain system that is not composed entirely of stormwater, except for the following:

1. Any discharge in compliance with a separate NPDES construction or building permit issued to a discharger, provider that the discharger is in full compliance with all

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5 requirements of them permit and other applicable laws;

2. Any discharge granted a discharge exemption by the California Regional Water Quality Board, Los Angeles Region, the Executive Officer of the aforesaid Board or an authorized representative or the State Water Resources Control Board;

3. Discharges resulting from:
a. Flows from riparian habitats or wetlands;
b. Diverted stream flows;
c. Springs;
d. Rising ground waters;
e. Uncontaminated groundwater infiltration;
f. Discharges or flows from emergency firefighting activities, g. Landscape irrigation;
h. Water line flushing;
i. Potable water sources provided the discharges are managed in accordance with an approved industry-wide standard pollution prevention practices developed by the American Water Works Association, California Nevada Section, or equivalent document;
j. Fountain drains;
k. Footing drains;
l. Air conditioning condensation;
m. Irrigation water;
n. Lawn watering;
o. Water from crawl space pumps;
p. Dechlorinated swimming pool discharges;
q. Individual residential car washing;
r. Street or sidewalk washing, and;
s. Discharges specifically allowed by law.
“Industrial General Permit” means a General Permit for Storm Water Discharges Associated with Industrial Activities. General NPDES permit issued by the State Water Board, which authorizes the discharge of stormwater from certain industrial activities under certain conditions.
“Industrial/Commercial Facility” means any facility involved and/or used in the production, manufacture, storage, transportation, distribution, exchange or sale of goods and/or commodities, and any facility involved and/or used in providing professional and non-professional services. This category of facilities includes, but is not limited to, any facility defined by either the Standard Industrial Classifications (SIC) or the North American Industry Classification System (NAICS). “LID” means Low Impact Development. LID consists of building and landscape features designed to retain or filter stormwater runoff. “Municipal Separate Storm Sewer System (MS4)” means a conveyance or system of conveyances (including roads with drainage systems, municipal streets, catch basins, curbs, gutter, ditches, man-made channels, or storm drains) (40 CFR § 122.26(b)(8)) that is the following:

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6 wastes, including special districts under State law such as a sewer district, flood control district or drainage district, or similar entity, or an Indian tribe or an authorized Indian tribal organization, or a designated and approved management agency under section 208 of the CWA that discharges to waters of the United States;

2. Designed or used for collecting or conveying stormwater; and

3. Which is not part of a Publicly Owned Treatment Works (POTW) as defined at 40 CFR § 122.2.
“New Development” means land-disturbing activities; structural development, including construction or installation of a building or structure, creation of impervious surfaces; and land subdivision.means and includes all constructionon unimproved properties, as well as all construction on improved properties which will result in: (1) an increase of fifty percent or greater in the size of a single family home; (2) an addition of one or more dwelling units to a multifamily structure; or (3) improvements valued at fifty percent or more of the value of existing improvements on residential property. "Non-Stormwater runoffDischarge” means the flow of any fluid that is not entirely composed of stormwater.
"NPDES" means the National Pollutant Discharge Elimination System. “NPDES construction permit” means a permit issued by the regional water quality control board to owners/developers for construction activity for sites five acres in size or larger to control sediment and other pollutants from entering the storm drain system. “NPDES industrial permit” means a permit issued by the regional water quality control board to owners/developers of specific categories of industrial facilities identified in federal regulations to discharge stormwater into the storm drain system. “Planning Priority Projects” means development projects subject to Permittee conditioning and approval for the design and implementation of post-construction controls to mitigate stormwater pollution, prior to completion of the project(s). “Regional Board” means the California Regional Water Quality Control Board, Los Angeles Region.
“Sidewalk Rinsing” means low-volume pressure washing of paved pedestrian walkways with average water usage of 0.006 gallons per square foot, with no cleaning agents, and proper disposal of all debris collected.
"Storm Drain System" means those facilities that convey stormwater runoff and suspended solids to the waters of the United States, including streets, alleys, roads, ditches, curbs, gutters, catch basins, conduits, streams, channels, creeks, and rivers. "Stormwater'' means water that originates from atmospheric moisture (rainfall, hail, snow, or snowmelt) and that falls onto land, water, or other surfaces. "Stormwater pollutionPollution preventionPrevention planPlan" ("SWPPP") means a plan, as required by a state general permit for discharges of stormwater (e.g., Construction General Permit or Industrial General Permit), identifying potential pollutant sources and describing the design, placement, and implementation of BMPs, to effectively prevent non-stormwater discharges and reduce pollutants in stormwater discharges

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7 from activities covered by the general permit.means the operator/owner-prepared plan that identifies BMPs for implementation and monitors the effectiveness of the BMPs for a specific commercial/industrial facility.
"Stormwater runoffRunoff“ means the surface flow of stormwaterpart of precipitation (rainfall or snowmelt) that travels across a surface to the storm drain system or receiving waters.
"Urban Runoff” means surface water flow produced by storm and non-storm events.

Non-storm events include flow from residential, commercial, or industrial activities involving the use of potable and non-potable water.

14.11.020 Responsibility for administrationAdministration.

This chapterChapter shall be administered by the office of the cityCity engineerEngineer. (Ord.1064 4,1997)

14.11.030 General Provisions.

A. The purpose and intent of this chapter is to protect the health and safety of the residents of the City by protecting the beneficial uses, marine habitats, and ecosystems of receiving water from pollutants carried by stormwater and nonstormwater discharges. The intent of the chapter is to enhance and protect the water quality of receiving waters consistent with the Clean Water Act.

A. C. The City Engineer shall establish and enforce uniform standards, guidelines, and/or criteria for specific discharges, connections and/or BMPs.14.11.040 Prohibited DischargesandActivities.

14.11.030040 Prohibited Discharges and activitiesActivities A. Except as otherwise conditionally authorized by the Permit or any other NPDES permit, waiver or waste discharge order issued by the U.S. EPA, the State Board, or a regional board, provided that the discharger is in full compliance with all requirements of the permit, waiver or order and other applicable laws and regulations, including the provisions of this chapter, and subject to any requirements specified by the Director, no person shall do the following:

1. Discharge non-stormwater to the City's storm drain system or to receiving waters except in compliance with the requirements of this Chapter;

2. Cause, allow, or facilitate any prohibited discharge; and

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8 Control Plan, California Toxics Rule, or Basin Plan, or that may cause or contribute to the violation of any receiving water limitation.

1. Authorized non-stormwater discharges separately regulated by an individual or general NPDES permit.

2. Authorized non-stormwater discharges separately regulated by a conditional waiver or WDRs for agricultural lands.

3. Temporary non-stormwater discharges authorized pursuant to sections 104(a) or 104(b) of the CERCLAomprehensive Environmental Response, Compensation, and Liability Act (CERCLA) that either: (i) will comply with water quality standards as applicable or relevant and appropriate requirements (“ARARs”) under section 121(d)(2) of CERCLA; or (ii) are subject to either (a) a written waiver of ARARs pursuant to section 121(d)(4) of CERCLA or (b) a written determination that compliance with ARARs is not practicable considering the exigencies of the situation pursuant to 40 CFR. Section 300.415(j).

4. Authorized non-stormwater discharges from emergency firefighting activities (i.e., discharges resulting from water use necessary for the protection of life or property from fire).

6. Conditionally exempt non-stormwater discharges as follows:
a. Conditionally Exempt Essential Non-Stormwater Discharges to include the following:
i. Discharges from essential non-emergency firefighting activities.
ii. Discharges from drinking water systems that are not otherwise regulated by an NPDES permit.
b. Conditionally Exempt Non-Essential Non-Stormwater Discharges to include the following:
i. Dewatering of lakes.
ii. Landscape irrigation.
iii. Dechlorinated/debrominated swimming pool/spa discharges not otherwise regulated by a separate NPDES permit.
iv. Dewatering of decorative fountains.
v. Non-commercial car washing by residents or by non-profit organizations.
vi. Street/sidewalk wash water.

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9 vii. Short-term releases of potable water with no additives or dyes for filming purposes.; and
viii. Potable wash water used to clean reservoir covers. c. Non-Stormwater Discharges to an ASBS are allowed as follows:
i. One of the conditionally exempt non-stormwater discharge categories in part 6.a. above.
ii. Essential for emergency response purposes, structural stability, and slope stability, which may include but are not limited to the following discharges:
a. Discharges associated with emergency firefighting
operations (i.e., discharges resulting from water use
necessary for the protection of life or property from fire). b. Foundation and footing drains;
c. Water from crawl space or basement pumps; and
d. Hillside dewatering.
iii. Naturally occurring discharges as follows:
a. Naturally occurring groundwater seepage via the MS4; b. Non-anthropogenic flows from a naturally occurring
stream via a culvert or MS4, as long asif there are no
contributions of anthropogenic runoff.

E. Littering and other discharge of polluting or damaging substances are prohibited.

1. No person shall cause any refuse, rubbish, food waste, garbage, or any other discarded or abandoned objects to be littered, thrown, deposited, left, accumulated, maintained or kept in or upon any street, alley, sidewalk, storm drain, inlet, catch basin, conduit, drainage structure, place of business, or upon any public or private property so that the same may or does become a pollutant which may or does enter the storm drain system or receiving waters, except when such materials are placed in containers, bags, recycling bins, or other lawfully established waste disposal facilities protected from stormwater or runoff.

2. No person shall cause the disposal of hazardous materials or hazardous wastes into trash containers used for municipal trash disposal.

3. No person shall cause to be discharged to the storm drain system or to

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10 receiving waters any pesticide, fungicide, or herbicide prohibited by the U.S. EPA or the California Department of Pesticide Regulation.

14.11.050 Prohibited Connections to the MS4.

A. Illicit Discharges and Connections. No person shall cause or permit illicit discharges to be made into the city's storm drain system, nor shall any person establish, use, maintain or continue an illicit connection to the city's storm drain system.

All illicit connections shall be removed.

B. Littering. No person shall throw, deposit, place, leave, maintain, keep or permit to be thrown, deposited, placed, left or maintained or kept, any refuse, rubbish, garbage, leaves, dirt, landscape debris, or any other discarded or abandoned objects, articles or accumulations, in or upon any street, alley, sidewalk, storm drain, inlet, catch basin conduit

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11 or drainage structure, business place, or upon any public or private plot of land in the city, so that the same might be or become a pollutant, except in containers, recycling bags or other lawfully established waste disposal facilities. It is illegal to dump, discard, abandon or otherwise deposit any refuse where the natural flow of stormwater might carry the same to any such flood water channel or structure, or in any fountain, pond, lake, stream, or any other body of water in a park or elsewhere in the city.

C. Industrial Activities. No person shall conduct any industrial activity in the city without obtaining all permits required by state or federal law, including a NPDES general industrial activity stormwater permit, when required. Each industrial discharger associated with construction activity or other discharger described in any general stormwater permit addressing such discharges as may be adopted by the United States Environmental Protection Agency, the State Water Resources Control Board, or the California Regional Water Quality Control Board, Los Angeles Region shall provide notice of intent to comply with and undertake all other activities required by any general stormwater permit applicable to such discharges. Each discharger identified in an individual NPDES permit relating to stormwater discharges shall comply with and undertake all activities required by such permit.

D. Discharge in Violation of Permit. Any discharge, either separately considered or when combined with other discharges, that would result in, or contribute to a violation of NPDES Permit Order No. 96-054, (which is available for viewing at San Dimas City Hall, city engineer's office), and any amendment, revision or re-issuance thereof, is prohibited. Liability for any such discharge shall be the responsibility of the person(s) causing or responsible for the discharge and such person(s) shall defend, indemnify and hold harmless the city in any administrative or judicial enforcement action relating to such discharge.

E. The discharge of untreated wash waters to the MS4 when gas stations, auto repair garages, or other types of automotive service facilities are cleaned is prohibited.

F. The discharge of untreated wastewater to the MS4 from mobile auto washing, steam cleaning, mobile carpet cleaning, and other such mobile commercial and industrial operations is prohibited.

G. To the maximum extent practicable, discharges to the MS4 from areas where repairs of machinery and equipment, including motor vehicles, which are visibly leaking oil, fluid or antifreeze, are made, is prohibited.

H. The discharge of untreated runoff to the MS4 from storage areas of materials containing grease, oil, or other hazardous substances, and uncovered receptacles containing hazardous materials is prohibited.

I. The discharge of commercial/municipal swimming pool filter backwash to the MS4 is prohibited.

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12 J. The discharge of untreated runoff from the washing of toxic materials from paved or unpaved areas to the MS4 is prohibited.

K. The washing of impervious surfaces in industrial/commercial areas that results in a discharge of untreated runoff to the MS4, unless specifically required by state or local health and safety codes, is prohibited or must be controlled to the maximum extent practicable.

L. The discharge from washing out concrete trucks to the MS4 is prohibited.

M. Industrial/commercial motor vehicle parking lots with more than twenty-five parking spaces that are located in areas potentially exposed to stormwater shall be swept, or some other equally effective measure taken, to remove debris on a regular basis.

N. The placement of machinery/equipment that is to be repaired or maintained shall be such that leaks, spills and other maintenance-related pollutants are not discharged to the MS4.

0. Illicit discharges and illicit connections to the MS4 is prohibited.

P. In order to control spills, dumping, or disposal of materials to the MS4 the following are prohibited:

1. Littering;

2. The disposal of leaves, dirt, or other landscape debris into a storm drain;

3. The discharge to the MS4 of any pesticide, fungicide, or herbicide banned by either the USEPA or the California Department of Pesticide Regulation;

4. The improper disposal of food wastes;

5. The disposal of hazardous wastes into trash containers used for municipal trash disposal so as not to cause a discharge to the MS4.

Q. In areas exposed to stormwater, the removal and lawful disposal of all fuels, chemicals, fuel and chemical wastes, animal wastes, garbage, batteries, and other materials which have potential adverse impacts on water quality is required.

R. Where best management practices and/or standard urban stormwater mitigation plan requirements have been duly and legally adopted by any federal, state of California, regional and/or local regulatory agency pertaining to any activity, operation or facility that causes or contributes to stormwater pollution or illicit discharges to the stormwater system, every person undertaking such activity or operation or owning or

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13 operating such facility shall comply with such requirements, including obtaining all necessary permits. If the requirements set forth in this chapter are more stringent than the best management practices and/or standard urban stormwater mitigation plan requirements duly and legally adopted by a federal, state of California, regional and/or local regulatory agency, the director of public works may waive the requirements imposed by this chapter upon finding of good cause. (Ord. 1112 § 1, 2000; Ord. 1064 § 4, 1997)

14.11.040060 Requirements for Existing Properties.

Any owner or occupant of property within the cityCity shall comply with the following requirementsbest management practices:

A. Any person engaged in activities which will or may result in pollutants entering the City storm drain system shall undertake all control measures and BMPs as the City Engineer may require to reduce such pollutants. Premises with a high potential threat of discharge may be required to implement a monitoring program meeting standards established by the City. Where best management practices guidelines or requirements have been adopted by any Federal, State, regional, and/or city agency, for any activity, operation, or facility which may cause or contribute to stormwater pollution or contamination, illicit discharges, and/or discharges of non-stormwater to the storm drain system, every person undertaking such activity or operation, or owning or operating such facility shall comply with such guidelines or requirements as may be identified by the City Engineer.

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14 and to record such agreement with the County Recorder’s office.

F. The following BMPs are required of every owner or occupant of any property:

7. Motor vehicle parking lots with a gravel/sediment base to implement BMPs to prevent the discharge of gravel and sediment to the MS4.

A. Use of Water. Runoff of water used for irrigation purposes shall be minimized to the maximum extent practicable. In addition, washing down of paved areas is prohibited, unless necessary for health or safety purposes as determined by the director of public works, and is not in violation of any other provision of this code. Runoff of water from the permitted washing down of paved areas shall be minimized to the maximum extent practicable.

B. The storage of materials, machinery and equipment, such as motor vehicle parts, containing grease, oil, or other hazardous substances, and unsealed receptacles containing hazardous materials, shall not be in areas susceptible to runoff.

C. Any machinery or equipment which is to be repaired in areas susceptible to runoff shall be placed on a pad of absorbent material to contain leaks, spills or small discharges.

D. The discharge of gray water to street or storm drains is prohibited. (Ord. 1064 § 4, 1997) G. The discharge of gray water to street or storm drains is prohibited.

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15 14.11.070 Industrial and Commercial Facilities
A. The following discharges from industrial or commercial activities are prohibited unless the discharge is in compliance with the provisions of this chapter:

1. Discharge of wash waters to the storm drain system from the cleaning of gas stations, auto repair garages, or other types of auto repair facilities;

2. Discharge of wastewater to the storm drain system from mobile auto washing, steam cleaning, mobile carpet cleaning, or other such mobile commercial and industrial operations;

3. Discharge to the storm drain system from areas where repair of machinery and equipment, including motor vehicles, which are visibly leaking oil, fluids, or coolants is undertaken;

4. Discharge to the storm drain system from storage areas for materials containing grease, oil, or hazardous materials, or from uncovered receptacles containing hazardous materials, grease, or oil;

5. Discharge of commercial/public swimming pool filter backwash to the storm
drain system;

6. Discharge from the washing of toxic materials from paved or unpaved areas to the storm drain system;

7. Discharge from the washing out of concrete trucks to the storm drain system; and

8. Discharge from the washing or rinsing of restaurant mats, equipment, or garbage bins or cans in such a manner that causes non-stormwater to enter the storm drain system.

B. Industrial/commercial facility sources required to obtain a NPDES permit. Any industrial or commercial facility required to have a NPDES permit shall retain onsite and, upon request, make immediately available to the director the following documents as evidence of compliance with permit requirements, as applicable:

1. A copy of a NPDES permit or notice of intent to comply with a general permit to discharge stormwater associated with industrial or construction activity as submitted to the State Board or report of waste discharge as submitted to a Regional Board of jurisdiction;

2. A waste discharge identification number issues by the State Board or copy of the NPDES permit issued by a Regional Board;

3. A SWPPP and a monitoring program plan or group monitoring plan;

4. Stormwater quality data;

5. Evidence of facility self-inspection; or

6. Evidence that facilities has filed a Notice of Non-Applicability (NONA) or any applicable waiver issued by the Los Angeles Water Board or State Water Board pertaining to stormwater discharges.

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16 C. Best management practices for industrial and commercial facilities. All industrial and commercial facilities shall implement BMPs which will effectively prevent the direct or indirect discharge of pollutants to the storm drain system or receiving waters to the maximum extent practicable. Minimum BMPs applicable to all industrial and commercial facilities include, but are not limited to the following:

1. Termination of all non-stormwater discharge to the storm drain system that is not specifically authorized by a NPDES permit;

2. Exercising general good housekeeping practices;

3. Incorporating regular scheduled preventative maintenance into operations;

4. Maintaining spill prevention and control procedures;

5. Implementing soil erosion control;

6. Posting on-site private storm drains to indicate that they are not to receive liquid, solid wastes, or pollutants;

7. Implementing regular cleaning of the on-site private storm drain system;

8. Ensuring that stormwater runoff is directed away from operating, processing, fueling, cleaning and storage areas;

9. Remove trash, debris, and free-standing oil/grease, spill/leaks from sidewalks and hard surfaces; and

10. Sidewalk washing should be performed using high pressure, low-volume spray washing using only potable water with no cleaning agents at an average usage of 0.006 gallons per square feet of sidewalk area.

14.11.050080 Low Impact Development Standards for New Development and Redevelopment.

14.11.050 Urban stormwater mitigation Low Impact Development Standards for New Development and Redevelopment plan for new developments.

A. Prior to the submittal of an application for a All Priority Development project, i.e., new development/redevelopment projects shall comply with the provisions of the City’s Low Impact Development Ordinance, Chapter 14.13. an applicant shall submit to the director of public works an urban stormwater mitigation plan.

B. Failure to comply with an approved urban stormwater mitigation plan after receiving any required planning approval shall be a misdemeanor.

The urban stormwater mitigation plan shall be designed to reduce projected runoff for a project through incorporation of design elements or principles that address the following goals in connection with both construction and long-term operation of the site:

Implement to the maximum extent practicable, requirements established by appropriate government agencies under CEQA, Section 404 of the Clean Water Act, local ordinances

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17 and other legal authorities intended to minimize impacts from stormwater runoff on the biological integrity of natural drainage systems and water bodies.

Maximize, to the maximum extent practicable, the percentage of permeable surfaces to allow more percolation of stormwater into the ground.

Minimize, to the maximum extent practicable, the amount of stormwater directed to impermeable areas and to the MS4.

Minimize, to the maximum extent practicable, parking lot pollution through the use of appropriate BMPs such as retention, infiltration and good housekeeping.

Establish reasonable limits on the clearing of vegetation from the project site including, but not limited to, regulation of the length of time during which soil may be exposed and, in certain sensitive cases, the prohibition of bare soil.

Provide for appropriate permanent controls to reduce stormwater pollutant load produced by the development site to the maximum extent practicable.

The city's evaluation of each urban stormwater mitigation plan will ascertain how well the proposed plan meets the combined objectives set forth in subsection B of this section. In addition, the city will analyze watershed characteristics and land uses and monitor or estimate water quality for each project. Each plan will be evaluated on its own merits according to the particular characteristics of the project and the site to be developed.

The director of public works shall approve or disapprove the plan within fourteen business days of submittal, or within fourteen business days of approval of the development project by the planning commission, where such approval is required. If the plan is disapproved, the reasons for disapproval shall be given in writing to the developer.Any plan disapproved by the director of public works or his or her designee may be revised by the developer and resubmitted for approval. A resubmitted plan will be approved or disapproved within fourteen business days of submission.

Notwithstanding planning commission approval of a development project, no building permit shall be issued until an urban stormwater mitigation plan has been approved by the director of public works.

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18 Full or partial waivers of compliance with this section may be obtained by persons who apply on forms supplied by the city and show that incorporation of design elements that address the objectives set forth in subsection B of this section is an economic and physical impossibility due to the particular configuration of the site or due to irreconcilable conflicts with other city requirements. Requests for waivers must be approved, in writing, by the community development department, the public works department, and the division of building and safety.

Compliance with an approved urban stormwater mitigation plan shall be a condition of any required planning approval.

Failure to comply with an approved urban stormwater mitigation plan after receiving any required planning approval shall be a misdemeanor. (Ord. 1064 § 4, 1997)

14.11.060090 Requirements for constructionConstruction projectsProjects.

A. No person shall commence any construction activity for which a permit is required by this Chapter or any law or regulation without implementing stormwater and runoff pollution mitigation measures required by such permit(s), law, regulation or this Chapter. In addition, prior to obtaining a grading or building permit, each operator of any construction activity shall submit evident to the City Engineer that all applicable permits have been obtained, including but not limited to the General Construction Activities Storm Water Permit and State Water Board 401 Water Quality Certification.

B. No grading permit shall be issued for developments with disturbed areas of one (1) acre or greater or which is part of a larger common plan of development unless the applicant can show that:

1. A notice of intent (NOI) to comply with the state construction activity stormwater permit has been file;

2. A stormwater pollution prevention plan (SWPPP) has been prepared; and

3. A post-construction plan meeting the low-impact development standards in Chapter 14.13 has been submitted.

D. The following minimum set of BMPs shall apply to all construction sites (regardless of size):

1. Site Management – housekeeping.

2. Erosion Controls – scheduling and preservation of existing vegetation.

3. Sediment Controls – perimeter controls and stabilized construction site entrance and exit.

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