A. The provisions of this Section contain requirements for construction activities and facility operations of development and redevelopment projects to comply with the current Municipal NPDES Permit, lessen the water quality impacts of development by using smart growth practices, and integrate LID design principles to mimic predevelopment hydrology through infiltration, evapotranspiration and rainfall harvest and use.
B. This Section contains requirements for stormwater pollution control measures in development and redevelopment projects and authorizes the City of Culver City to further define and adopt stormwater pollution control measures, to develop LID principles and requirements, including but not limited to the objectives and specifications for integration of LID strategies, and to grant alternative compliance as allowed by the Municipal NPDES Permit.
C. The following development and redevelopment projects, termed "Planning Priority Projects," shall comply with the requirements of the most recent Municipal NPDES Permit:
1. All development projects equal to one (1) acre or greater of disturbed area that add more than ten thousand (10,000) square feet of impervious surface area.
2. Industrial parks with ten thousand (10,000) square feet or more of surface area.
3. Commercial malls with ten thousand (10,000) square feet or more of surface area.
4. Retail gasoline outlets with five thousand (5,000) square feet or more of surface area.
5. Commercial car washes with five thousand (5,000) square feet or more of surface area.
6. Restaurants (SIC of 5812) with five thousand (5,000) square feet or more of surface area.
7. Parking lots with five thousand (5,000) square feet or more of impervious surface area, or with twenty-five (25) or more parking spaces.
8. Street and road construction of ten thousand (10,000) square feet or more of impervious surface area.
9. Automotive service facilities (SIC of 5013, 5014, 5511, 5541, 7532-7534 and 7536-7539) with five thousand (5,000) square feet or more of surface area.
10. Projects located in or directly adjacent to, or discharging directly to an Significant Ecological Area, where the development will:
a. Discharge stormwater runoff that is likely to impact a sensitive biological species or habitat; and
b. Create two thousand five hundred (2,500) square feet or more of impervious surface area.
11. Single-family hillside homes.
12. Redevelopment of any Planning Priority Project. Provided, further, that:
a. Where redevelopment results in alteration to more than fifty percent (50%) of the impervious surface of a previously existing Planning Priority Project and the existing Planning Priority Project was not subject to post-construction stormwater quality control requirements, the entire project must be brought into compliance with the most recent Municipal NPDES Permit.
b. Where redevelopment results in alteration of less than fifty percent (50%) of the impervious surface of a previously existing Planning Priority Project and the existing Planning Priority Project was not subject to post-construction stormwater quality control requirements, only the alteration must be brought into compliance with the most recent Municipal NPDES Permit.
13. Any other project as deemed appropriate by the Director of Public Works/City Engineer.
D. Stormwater Pollution Control Requirements. The site for every Planning Priority Project shall be designed to control pollutants, pollutant loads, and runoff volume to the maximum extent practicable by minimizing impervious surface area and controlling runoff from impervious surfaces through infiltration, evapotranspiration, bioretention and/or rainfall harvest and use. More specifically:
1. A single-family hillside home development shall include mitigation measures to:
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; and
e. Direct surface flow to vegetated areas before discharge, unless the diversion would result in slope instability.
2. Street and road construction of ten thousand (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-833-F-08-009) to the maximum extent practicable.
3. The remainder of Planning Priority Projects shall prepare a LID Plan to comply with the following requirements of the most recent Municipal NPDES Permit:
a. (1) Retain stormwater runoff onsite for the Stormwater Quality Design Volume (SWQDv), defined as the runoff from:
(2) The eighty-fifth (85th) percentile twenty- four (24)-hour runoff event as determined from the Los Angeles County eighty-fifth (85th) percentile precipitation isohyetal map.
b. Minimize hydromodification impacts to natural drainage systems as defined in the Municipal NPDES Permit. Hydromodification requirements are further specified in Southern California Coastal Water Research Project's Hydromodification Assessment and Management in California and California Stormwater Quality Association's Municipal BMP Handbook.
c. When, as determined by the City of Culver City and/or the Los Angeles Regional Water Quality Control Board, one hundred percent (100%) onsite retention of the SWQDv is technically infeasible, partially or fully, the infeasibility shall be demonstrated in the submitted LID Plan. The technical infeasibility may result from conditions that may include, but are not limited to:
(1) The infiltration rate of saturated in-situ soils is less than three-tenths (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 onsite.
(2) Locations where seasonal high groundwater is within five (5) to ten (10) feet of surface grade;
(3) Locations within one hundred (100) feet of a groundwater well used for drinking water;
(4) Brownfield development sites or other locations where pollutant mobilization is a documented concern;
(5) Locations with potential geotechnical hazards;
(6) 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.
d. If partial or complete onsite retention is technically infeasible, the project site may biofiltrate one and a half (1.5) times the portion of the remaining SWQDv that is not reliably retained onsite. Biofiltration BMPs must adhere to the design specifications provided in the Municipal NPDES Permit and/or the LID Manual.
(1) The remaining SWQDv that cannot be retained or biofiltered onsite must be treated onsite to reduce pollutant loading. BMPs must be selected and designed to meet pollutant-specific benchmarks as required per the Municipal NPDES Permit. Flow-through BMPs may be used to treat the remaining SWQDv and must be sized based on a rainfall intensity of two-tenths (0.2) inches per hour or the one (1)-year, one (1)-hour rainfall intensity as determined from the most recent Los Angeles County isohyetal map, whichever is greater.
(2) BMPs must be maintained according to their submitted Maintenance Covenant and Agreement.
e. A Multi-Phased Project may comply with the standards and requirements of this Section for all of its phases by: (a) designing a system acceptable to the City of Culver City to satisfy these standards and requirements for the entire site during the first phase, and (b) implementing these standards and requirements for each phase of development or redevelopment of the site during the first phase or prior to commencement of construction of a later phase, to the extent necessary to treat the stormwater from such later phase. For purposes of this Section, MULTI-PHASED PROJECT shall mean any Planning Priority Project implemented over more than one phase and the site of a Multi-Phased Project shall include any land and water area designed and used to store, treat or manage stormwater runoff in connection with the development or redevelopment, including any tracts, lots, or parcels of real property, whether Developed or not, associated with, functionally connected to, or under common ownership or control with such development or redevelopment.
E. Post-development stormwater mitigation. A site-specific plan to mitigate post-development stormwater pollution for new development and redevelopment projects not requiring a SUSMP, but which may potentially have adverse impacts on post-development stormwater quality shall be required where one (1) or more of the following project characteristics exist:
1. Vehicle or equipment fueling areas;
2. Vehicle or equipment maintenance areas, including washing and repair;
3. Commercial or industrial waste handling or storage;
4. Outdoor handling or storage of hazardous materials;
5. Outdoor manufacturing areas;
6. Outdoor food handling or processing;
7. Outdoor animal care, confinement, or slaughter; or
8. Outdoor horticulture activities.
F. Issuance of permits. No permit may be issued for any new development or redevelopment project until the Director confirms that the project plans comply with the applicable stormwater mitigation and numerical design criteria requirements.
G. Final Inspection or Occupancy Permit. As a condition for conducting a Final Inspection or issuing any Occupancy Permit, whichever is applicable, for a project subject to this Section, the Director shall require facility operators and/or owners to construct all the stormwater pollution control BMPs and structural and/or treatment control BMPs that are shown on the approved project plans, and to submit a signed certification statement stating that the site and all structural and/or treatment control BMPs shall be maintained in compliance with the SUSMP and other applicable regulatory requirements.
H. Transfer of properties subject to requirements for maintenance of structural and treatment control BMPs.
1. The transfer of ownership, sale or lease of a property subject to requirements for maintenance of structural and/or treatment control BMPs shall include provisions requiring the new owner and his or her successors to:
a. Assume responsibility for maintenance of any existing structural or treatment control BMP; or
b. Replace any existing structural or treatment control BMP with new control measures or BMPs meeting the most current standards of the City and the SUSMP.
2. Such requirements shall be included in any sale, lease agreement or deed for the property. The condition of transfer shall include a provision that the new owner and his or her successors conduct routine maintenance inspections of all structural and/or treatment control BMPs to ensure they are in good working order at all times, and retain proof of inspection.
3. For residential properties where the structural and/or treatment control BMPs are located within a common area that will be maintained by a homeowner's association, language regarding the responsibility for maintenance shall be included in the project's conditions, covenants and restrictions (CC&Rs).
a. Printed educational materials will be required to accompany the first deed transfer to highlight the existence of the requirement and to provide information on: what stormwater management facilities are present, signs that maintenance is needed, and how the necessary maintenance can be performed.
b. The transfer of this information shall also be required with any subsequent sale of the property.
4. If structural and/or treatment control BMPs are located within an area proposed for dedication as an easement or fee title to the City or Redevelopment Agency, the BMPs shall remain the property and responsibility of the developer/owner until the dedication is accepted by the City Council and recorded with the Los Angeles County Recorder's Office.
I. California Environmental Quality Act (CEQA). Provisions of this Section shall be complimentary to, and shall not replace, any applicable requirements for stormwater mitigation required under CEQA.
(Ord. 2014-008 § 1 (part))