Article 3

An owner or occupant of any property shall comply with the following good housekeeping requirements:

• A. 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.

• B. Runoff from landscape irrigation, air conditioning condensate, water line flushing, foundation/footing drains, individual residential car washing, dechlorinated swimming pool discharges and sidewalk washing shall be conducted in a manner not in violation of other provisions of this Code.

• C. 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 Code. Runoff from authorized washing of paved areas shall be minimized to the extent practicable.

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

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

• F. All motor vehicle parking lots located in areas exposed to storm water or otherwise susceptible to runoff shall have debris and litter removed by regular sweeping or other equally effective measures. All parking lots shall be completely swept and maintained free of debris and litter at least weekly and additionally as determined by the City Manager or designee to prevent further accumulation and spread of litter. Parking lots serving restaurants and swap meets shall be completely swept and maintained free of debris and litter on each day a restaurant or swap meet is open for business to the public. Areas adjacent to a parking lot, including, but not limited to, planters, loading and unloading areas, and surrounding public rights-of-way shall be maintained free of debris and litter by sweeping and other equally effective measures. Such debris and litter shall be collected and properly disposed of in compliance with all applicable local, State, and Federal regulations.

• (Prior code § 48-4; Ord. 1141 § 2, 2020)

All BMPs required as a condition of any permit for construction activity granted pursuant to Title 15 of this Code shall be maintained in full force and effect during the term of the project, unless otherwise authorized by the Director.

(Prior code § 48-4.1)

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City of Paramount, CA § 8.20.180

HEALTH AND SAFETY

§ 8.20.210

All industrial and commercial facilities shall implement BMPs to the maximum extent practicable. Minimum BMPs applicable to all industrial and commercial facilities include, but are not limited to:

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

• B. Exercising general good housekeeping practices;

• C. Incorporating regular scheduled preventive maintenance into operations;

• D. Maintaining spill prevention and control procedures;

• E. Implementing soil erosion control;

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

• G. Implementing regular cleaning of the on-site private storm drain system; and

• H. Insuring that stormwater runoff is directed away from operating, processing, fueling, cleaning and storage areas.

(Prior code § 48-4.2)

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 Director. Such facilities may be subject to plan review, application and issuance of operating permits pursuant to Chapter 13.08 of this Code.

(Prior code § 48-4.3)

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

(Prior code § 48-4.4)

• A. Objective. The provisions of this section establish requirements for construction activities and facility operations of development and redevelopment projects to comply with the current "Order No. R4-205.44.00175," to lessen the water quality impacts of development by using smart growth practices, and integrate LID practices and standards for stormwater pollution mitigation through means of infiltration, evapotranspiration, biofiltration, and rainfall harvest and use. LID shall be inclusive of new development and/or redevelopment requirements.

• B. Scope. This section contains requirements for stormwater pollution control measures in

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City of Paramount, CA § 8.20.210

PARAMOUNT CODE

§ 8.20.210

development and redevelopment projects and authorizes the City to further define and adopt stormwater pollution control measures, and to develop LID principles and requirements, including, but not limited to, the objectives and specifications for integration of LID strategies, grant waivers from the LID requirements, and collect funds for projects that are granted waivers. Except as otherwise provided herein, the City shall administer, implement, and enforce the provisions of this section.

• C. Applicability. 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), are:

  1. All development projects equal to one acre or greater of disturbed area that adds more than 10,000 square feet of impervious surface area.

  2. Industrial parks 10,000 square feet or more of impervious surface area.

  3. Commercial malls 10,000 square feet or more of impervious surface area.

  4. Retail gasoline outlets with 5,000 square feet or more of impervious surface area.

  5. Restaurants (Standard Industrial Classification (SIC) of 5812) with 5,000 square feet or more of impervious surface area.

  6. Parking lots with 5,000 square feet or more of impervious surface area, or with 25 or more parking spaces.

  7. Streets and roads construction of 10,000 square feet or more of impervious surface area. Street and road construction applies to standalone streets, roads, highways, and freeway projects, and also applies to streets within larger projects.

  8. Automotive service facilities (Standard Industrial Classification (SIC) of 5013, 5014, 5511, 5541, 7515.12.07534 and 7512.40.07539) 5,000 square feet or more of impervious surface area.

  9. Redevelopment Projects.

     • a. Land disturbing activity that results in the creation or addition or replacement of 5,000 square feet or more of impervious surface area on an already developed site of planning priority project categories.

• b. Where redevelopment results in an alteration to more than 50% of impervious surfaces of a previously existing development, and the existing development was not subject to post-construction stormwater quality control requirements, the entire project must be mitigated.

  - c. Where redevelopment results in an alteration of less than 50% of impervious surfaces of a previously existing development, and the existing development was not subject to post-construction stormwater quality control requirements, only the alteration must be mitigated, and not the entire development. 
  
  - d. 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
  

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City of Paramount, CA § 8.20.210

HEALTH AND SAFETY

§ 8.20.210

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

  - e. Existing single-family dwelling and accessory structures are exempt from the redevelopment requirements unless such projects create, add, or replace 10,000 square feet of impervious surface area. 

• D. Effective Date. The planning and land development requirements contained in Section 7 of Order No. R4-205.44.00175 shall become effective 30 days from the adoption of the Order. This includes planning priority projects that are discretionary permit projects or project phases that have not been deemed complete for processing, or discretionary permit projects without vesting tentative maps that have not requested and received an extension of previously granted approvals within 90 days of adoption of the Order. Projects that have been deemed complete within 90 days of adoption of the Order are not subject to the requirements of Section 7.

• E. Specific Requirements. The site for every planning priority project shall be designed to control pollutants, pollutant loads, and runoff volume to the maximum extent feasible by minimizing impervious surface area and controlling runoff from impervious surfaces through infiltration, evapotranspiration, bioretention and/or rainfall harvest and use.

  1. Street and road construction of 10,000 square feet or more of impervious surface shall follow USEPA guidance regarding Managing Wet Weather with Green Infrastructure: Green Streets (December 2008 EPA-813.20.0F-08-009) to the maximum extent practicable.

  2. The remainder of planning priority projects shall prepare a LID Plan to comply with the following:

     • a. Retain stormwater runoff on site for the Stormwater Quality Design Volume (SWQDv) defined as the runoff from:

       • i. The 85th percentile 24-hour runoff event as determined from the Los Angeles County 85th percentile precipitation isohyetal map; or

• ii. The volume of runoff produced from a 0.75 inch, 24-hour rain event, whichever is greater.

iii. (2,722.5 ft3/acre)[(AI)(0.9)+(AP+AU)(CU)] SWQDv = (I85%/I0.75)

• AI = Area of impervious coverage in acres

• AP = Area of pervious coverage in acres

• AU = Area of undeveloped area in acres

• CU = Undeveloped runoff coefficient

• I85% = Intensity of the storm for the 85th percentile 24-hour storm

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City of Paramount, CA

PARAMOUNT CODE

§ 8.20.210

§ 8.20.210

  - I0.75 = Intensity of the storm for the 0.75 inch, 24-hour rain event 

• b. To demonstrate technical infeasibility, the project applicant must demonstrate that the project cannot reliably retain 100% of the SWQDv on site, even with the maximum application of green roofs and rainwater harvest and use, and that compliance with the applicable post-construction requirements would be technically infeasible by submitting a site-specific hydrologic and/or design analysis conducted and endorsed by a registered professional engineer, geologist, architect, and/or landscape architect. Technical infeasibility may result from conditions including the following:

  • i. The infiltration rate of saturated in-situ soils is less than 0.3-inch per hour and it is not technically feasible to amend the in-situ soils to attain an infiltration rate necessary to achieve reliable performance of infiltration or bioretention BMPs in retaining the SWQDv on site;

  • ii. Locations where seasonal high groundwater is within five to 10 feet of surface grade;

  • iii. Locations within 100 feet of a groundwater well used for drinking water;

  • iv. Brownfield development sites or other locations where pollutant mobilization is a documented concern;

  • v. Smart growth and infill or redevelopment locations where the density and/ or nature of the project would create significant difficulty for compliance with the onsite volume retention requirement.

• c. If partial or complete onsite retention is technically infeasible, the project site may biofiltrate one and one-half times the portion of the remaining SWQDv that is not reliably retained onsite. Biofiltration BMPs must adhere to the design specifications provided in Attachment H of Order No. R4-205.44.00175.

Additional alternative compliance options such as offsite infiltration and groundwater replenishment projects may be available to the project site. The project site should contact the City of Paramount to determine eligibility.

• d. The remaining SWQDv that cannot be retained or bioretained onsite must be treated onsite to reduce pollutant loading. BMPs must be selected and designed to meet pollutant-specific benchmarks as required per Table 11 of Order No. R4-205.44.00175. Flow-through BMPs may be used to treat the remaining SWQDv and must be sized based on a rainfall intensity of:

  • i. Two-tenths of an inch per hour; or

  • ii. The one-year, one-hour rainfall intensity as determined from the most recent Los Angeles County isohyetal map, whichever is greater.

• F. Content of the LID Plan. The LID plan required by this section shall be prepared by a registered civil engineer, licensed architect, landscape architect or any other professional knowledgeable about stormwater quality issues and shall document in detail the requirements established above. The plan shall identify the treatment BMPs that are required to reduce the pollutant load from the discharges of the SWQDv that cannot be

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City of Paramount, CA § 8.20.210

HEALTH AND SAFETY

§ 8.20.210

infiltrated, bioretained or captured and used on the development and redevelopment site and the BMPs that are proposed to treat the discharge from the property above the SWQDv. The LID plan shall also identify the following:

1. Provide Storm Drain System Stenciling and Signage. All storm drain inlets from a project shall be clearly labeled to indicate that "No Dumping, Drains to Ocean." Label shall be maintained at least annually as needed.

2. Proper Design of Trash Storage Areas. Trash enclosure areas shall not be designed in the path of drainage nor shall roof drainage downspouts discharge to the trash enclosure.

3. Vehicle/Equipment Wash Areas. If a project is designed with a vehicle/equipment wash area the design shall include a roof to prevent rainwater from entering the area along with a berm to prevent site drainage from entering the area. The wash area shall be connected to the sanitary sewer.

4. Proof of Ongoing Maintenance. The plan shall incorporate record keeping standards to document maintenance of structural BMPs to assure ongoing operation of the system. Records shall be kept for three years. The records shall be made available for inspection upon the request of the City Engineer, the Regional Water Quality Control Board or the USEPA or their designated agent during normal business hours.

• G. Project Specific Issues to Be Addressed by the LID Plan. In addition to the items identified above the LID plan shall also consider issues unique to the occupancy:

  1. Automotive Repair Shops.

     • a. Proper Design of Fueling Areas. If provided at an automotive repair shop fueling facilities shall be designed as required for retail gasoline outlets below.

     • b. Proper Design of Outside Material Storage Areas. Areas used for storage of vehicles under repair or for storage of spare parts or the storage of used oil products shall be designed to minimize the exposure of stored cars, parts or fluids to rainfall.

     • c. Proper Design of Maintenance Bays. Repair/maintenance bays shall be within a building or under a roof to eliminate the exposure of vehicles being repaired to rainfall. The bays shall also be designed to allow for the collection of all fluid spills and floor wash down runoff. Fluid spills and floor wash down runoff shall either be collected and discharged to the Sanitary sewer or shall be collected by other means and disposed of as required by State law or USEPA regulations. Automotive fluids and greases shall not be discharged to areas exposed to rainfall.

all. The bays shall also be designed to allow for the collection of all fluid spills and floor wash down runoff. Fluid spills and floor wash down runoff shall either be collected and discharged to the Sanitary sewer or shall be collected by other means and disposed of as required by State law or USEPA regulations. Automotive fluids and greases shall not be discharged to areas exposed to rainfall.

  - d. Spill Prevention and Cleanup. Spill prevention and cleanup materials shall be maintained on site and staff shall be trained in its proper use. 

2. Industrial/Commercial Developments with More Than 10,000 Square Feet of Impervious Area.

   • a. Proper Design of Outside Material Storage Areas. Areas used for storage of storage of raw materials, finished products or merchandise shall be designed to

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City of Paramount, CA § 8.20.210

PARAMOUNT CODE

§ 8.20.210

minimize the exposure of stored materials to rainfall.

• b. Proper Design of Maintenance Bays. Repair/maintenance bays shall be within a building or under a roof to eliminate the maintenance of vehicles from rainfall. The bays shall also be designed to allow for the collection of all fluid spills and floor wash down runoff. Fluid spills and floor wash down runoff shall either be collected and discharged to the sanitary sewer or shall be collected by other means and disposed of as required by State law or US EPA regulations. Automotive fluids and greases shall not be discharged to areas exposed to rainfall.

• c. Proper Design of Loading and Unloading Areas. Loading and unloading areas shall be roofed where practical to limit the exposure of materials to rainfall. Spill prevention and cleanup materials shall be maintained on site and staff shall be trained in its proper use.

3. Restaurants.

   • a. Properly Designed Equipment/Accessory Wash Areas. Projects in this classification shall be designed with an area for the washing of floor mats and other large equipment that is connected to the sanitary sewer system. The area shall be roofed to prevent the entrance of rainwater or shall be designed to activate a valve to transfer the discharge from the storm drain to the sanitary sewer when mats or equipment are being washed. The operator may, upon submission of substantial proof, eliminate the wash area if no floor mats or equipment will be washed outside.

   • b. Proper Design of Outside Storage Areas. Projects shall be designed to limit the exposure to rainfall or rainwater runoff for materials stored outside. This provision shall apply to, but not be limited to, the storage of fryer fat stored for recycling, cardboard or paper storage intended for recycling, and waste food products stored for recycling or disposal. The storage of these materials shall be under a roof whenever possible.

4. Retail Gasoline Outlets.

   • a. Proper Design of Fueling Areas. Fueling facilities for a new retail gasoline outlet project shall be constructed in compliance with the Service Station Managers Association guidelines.

• b. Proper Design of Outside Material Storage Areas. Areas used for storage of vehicles under repair or for storage of spare parts or the storage of used oil products shall be designed to minimize the exposure of stored cars, parts or fluids to rainfall.

  • c. Proper Design of Maintenance Bays. Repair/maintenance bays shall be within a building or under a roof to eliminate the exposure of vehicles being repaired to rainfall. The bays shall also be designed to allow for the collection of all fluid spills and floor wash down runoff. Fluid spills and floor wash down runoff shall either be collected and discharged to the Sanitary sewer or shall be collected by other means and disposed of as required by State law or US EPA regulations. Automotive fluids and greases shall not be discharged to areas exposed to

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City of Paramount, CA § 8.20.210

HEALTH AND SAFETY

§ 8.20.210

rainfall.

5. Parking Lots.

   • a. As required above the SWQDv shall be retained on site for infiltration.

   • b. Sweep lot regularly to limit the accumulation of trash and debris. Also inspect the lot once per month for the accumulation of oil on the parking lot pavement. The inspection shall be documented with an inspection report and any accumulated oil or grease shall be removed to limit the exposure of oil and grease to rainfall.

• H. Review of the LID Plan by the City. The City shall review the LID plan to assure that all elements of the plan have been addressed and that the applicant has identified the areas to be set aside for the infiltration of the SWQDv and for the BMPs necessary to protect the storm drain system. If the plan is found to comply with the provisions of this section the grading and building permits may be issued for the project. If during construction, the plan is found to be deficient by the City or any other interested party the applicant shall amend the plan to address the deficiencies.

• I. Filing of LID Plan with the County Recorder. Upon acceptance of the LID plan by the City the applicant shall file a signed original of the plan with the County Recorder. The document shall be binding on the applicant and all successors in interest to the property. The form shall be provided by the City and shall only be amended or deleted from title with the consent of the City.

• J. Other Agencies of the City of Paramount. All Paramount departments, offices, entities and agencies, shall establish administrative procedures necessary to implement the provisions of this chapter on the development and redevelopment projects and report their activities to the Public Works Department.

• K. Validity. If any provision of this chapter is found to be unconstitutional or otherwise invalid by any court of competent jurisdiction, such invalidity shall not affect remaining provisions of this chapter are declared to be severable.

• (Prior code § 48-4.5)

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City of Paramount, CA

HEALTH AND SAFETY

§ 8.20.220

§ 8.20.260