Montebello Municipal Code Ch. 8.36 Storm Water and Urban Runoff Pollution Prevention

The purpose of this chapter is to protect and improve water quality of receiving waters by:

A. Reducing illicit discharges to the municipal storm water system to the maximum extent practicable.

B. Eliminating illicit connections to the municipal storm water system.

C. Eliminating spillage, dumping, and disposal of pollutant materials into the municipal storm water system.

D. Reducing pollutant loads in storm water and urban runoff, from land uses and activities identified in the municipal NPDES permit.

The provisions of this chapter are adopted pursuant to the Federal Water Pollution Control Act, also known as the "Clean Water Act," codified and amended at 33 U.S.C. 1251 et seq. The intent of this chapter is to enhance and protect the water quality of the receiving waters of the United States in a manner that is consistent with the Clean Water Act and acts amendatory thereof or supplementary thereto; applicable implementing regulations; the municipal NPDES permit, and any amendment, revision, or re-issuance thereof.

(Ord. 2245 § 1 (part), 2002)

For purposes of the provisions of this chapter concerning water quality hereinafter set forth, the following words and phrases shall be construed to have the meanings set forth, unless it is apparent from the context that a different meaning is intended. If the definition of any term contained in this chapter conflicts with the definition of the same term in Order No. R4-2012-0175, issued by the California Regional Water Quality Control Board Los Angeles Region on November 8, 2012, then the definition contained in Order No. R4-2012-0175 shall govern:

"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 (NAICS) codes. For inspection purposes, permittees need not inspect facilities with SIC codes 5013, 5014, 5511, 5541, 7532-7534, and 7536-7539 provided that these facilities have no outside activities or materials that may be exposed to stormwater.

"Basin plan" means the Water Quality Control Plan, Los Angeles Region, Basin Plan for the Coastal Watersheds of Los Angeles and Ventura Counties, adopted by the Regional Water Board on June 13, 1994 and subsequent amendments.

"Best management practice" or "BMP" means practices or physical devices or systems designed to prevent or reduce pollutant loading from stormwater or non-stormwater discharges to receiving waters, or designed to reduce the volume of stormwater or non-stormwater discharged to the receiving water.

"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. As used in this chapter, "biofiltration" includes only systems designed to facilitate incidental infiltration or achieve the equivalent pollutant reduction as biofiltration BMPs with an underdrain (subject to approval by the Regional Board's Executive Officer). Biofiltration BMPs include bioretention systems with an underdrain and bioswales.

"Bioretention" means a LID BMP that reduces stormwater runoff by intercepting rainfall on vegetative canopy, and through evapotranspiration and infiltration. A bioretention system may include, but is not limited to, a minimum two-foot top layer of a specified soil and compost mixture underlain by a gravel-filled temporary storage pit dug into the in-situ soil. A bioretention BMP may be designed with an overflow drain, but may not include an underdrain. If a bioretention BMP is designed or constructed with an underdrain, then it is regulated by Order No. R4-2012-0175 as a biofiltration BMP.

"Bioswale" means a LID BMP consisting of a shallow channel lined with grass or other dense, low-growing vegetation. Bioswales are designed to collect stormwater runoff and to achieve a uniform sheet flow through the dense vegetation for a period of several minutes.

"Clean Water Act" or "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: 1) emergency construction activities required to immediately protect public health and safety; or 2) routine maintenance activities (as defined below). 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.

"Control" means to minimize, reduce or eliminate by technological, legal, contractual, or other means, the discharge of pollutants from an activity or activities.

"Development" means construction, rehabilitation, redevelopment or reconstruction of: 1) any public or private residential project (whether single-family, multi-unit or planned unit development); 2) industrial, commercial, retail, and other non-residential projects, including public agency projects; or 3) 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 two hundred feet of the contiguous zone required for the continued maintenance, function, and structural stability of the environmentally sensitive area.

"Discharge" means any release, spill, leak, pump, flow, escape, dumping, or disposal of any liquid, semi-solid, or solid substance.

"Disturbed area" means an area that is altered as a result of clearing, grading, and/or excavation.

"Executive officer" means Executive Officer of the California Regional Water Quality Control Board, Los Angeles.

"Flow-through treatment BMPs" means a 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" or "GCASP" means the general NPDES permit adopted by the state board which authorizes the discharge of stormwater from construction activities under certain conditions.

"General industrial activities storm water permit" or "GIASP" means the general NPDES permit adopted by the state board which authorizes the discharge of stormwater from certain industrial 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. A bioretention BMP's 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 shall not be designed or constructed with an underdrain.

"Hillside" means a property located in an area with known erosive soil conditions, where the development contemplates grading on any natural slope that is 25 percent or greater and where grading contemplates cut or fill slopes.

"Illicit connection" means any manmade 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 or from the MS4 into a receiving water that is prohibited under local, state, or federal statutes, ordinances, codes, or regulations. The term illicit discharge includes any non-storm water discharge, except authorized non-storm water discharges; conditionally exempt non-storm water discharges; and non-storm water discharges resulting from natural flows specifically identified in Part III.A.1.d. of the Municipal NPDES permit.

"Industrial activity" means any of the ten classifications of industrial facilities specified in 40 Code of Federal Regulations Section 122.26(b)(14), defined by Standard Industrial Classification (SIC) and which is required to obtain a NPDES permit, not including construction activities.

"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). Facility ownership (federal, state, municipal, private) and profit motive of the facility are not factors in this definition.

"Industrial park" means land development that is set aside for industrial development. Industrial parks may include 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 onsite soils. Examples of infiltration BMPs include infiltration basins, dry wells, and pervious pavement.

"Low impact development" or "LID" consists of building and landscape features designed to retain or filter stormwater runoff.

"Maximum extent practical" (MEP) means the extent to which the city can reduce the discharge of pollutants in stormwater runoff. MEP requires selecting and implementing effective BMPs, and rejecting applicable BMPs only where: (i) other effective BMPs will service the same purpose; (ii) the BMPs would not be technically feasible; or (iii) the cost would be prohibitive. Factors considered include, but are not limited to:

(i) Effectiveness: Whether the BMP addresses a pollutant of concern.

(ii) Compliance: Whether the BMP complies with stormwater regulations, as well as other environmental regulations.

(iii) Public acceptance: Whether the BMP has public support.

(iv) Cost: Whether the cost of implementing the BMP has a reasonable relationship to the pollution control benefits achieved.

(v) Technical feasibility: Whether the BMP is technically feasible, considering soils, geography, and water resources.

"Municipal NPDES permit" means California Regional Water Quality Control Board, Los Angeles Region, Order No. 01-182, NPDES Permit No. CAS004001, Waste Discharge Requirements for Municipal Storm Water and Urban Runoff Discharges Within the County of Los Angeles, and the Incorporated Cities Therein, Except the City of Long Beach, and any amendment thereto or re-issuance thereof.

"Municipal separate storm sewer system" (referred to herein as "MS4"), means a conveyance or system of conveyances (including roads with drainage systems, municipal streets, catch basins, curbs, gutters, ditches, manmade channels, or storm drains):

(i) 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;

(ii) Designed or used for collecting or conveying stormwater;

(iii) Which is not a combined sewer; and

(iv) Which is not part of a publicly owned treatment works (POTW) as defined in 40 CFR Section 122.2. (40 CFR Section 122.26(b)(8)).

"National Pollutant Discharge Elimination System" or "NPDES" means the national permitting program for issuing, modifying, revoking and reissuing, terminating, monitoring and enforcing permits, and imposing and enforcing pretreatment requirements, under Clean Water Act (CWA) Sections 307, 402, 318, and 405. The term includes an "approved program."

"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 an improved drainage system.

"New development" means land disturbing activities; structural development, including construction or installation of a building or structure, creation of impervious surfaces; and land subdivision.

"Non-stormwater discharge" means any discharge to a municipal storm drain system that is not composed entirely of stormwater.

"Outfall" means a point source as defined by 40 CFR 122.2 at the point where a municipal separate storm sewer discharges to waters of the United States and does not include open conveyances connecting two municipal separate storm sewers, or pipes, tunnels or other conveyances with connect segments of the same stream or other waters of the United Sates and are used to convey waters of the United States.

"Owner" as applied to a building or real property, means any part owner, joint owner, tenant in common, tenant in partnership, joint tenant or tenant by the entirety of the whole or of a part of such building or real property.

"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 five thousand square feet or more of surface area, or with twenty-five or more parking spaces.

"Person" means, within the context of this chapter, any natural person, firm, association, organization, partnership, business trust, corporation or company.

"Pollutant" means any "pollutant" defined in Section 502(6) of the Federal Clean Water Act and incorporated by reference into the California Water Code Section 13373.

"Planning priority projects" means the following, which shall comply with this chapter:

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

2. Industrial parks ten thousand square feet or more of surface area.

3. Commercial malls ten thousand square feet or more of surface area.

4. Retail gasoline outlets with five thousand square feet or more of surface area.

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

6. Parking lots with five thousand square feet or more of impervious surface area or with twenty-five or more parking spaces.

7. Streets and road construction of ten thousand square feet or more of impervious surface area.

8. Automotive service facilities (SIC of 5013, 5014, 5511, 5541, 7532-7534 and 7536-7539) with five thousand square feet or more of surface area.

9. Projects in, near or discharging to environmentally sensitive areas.

10. Single-family hillside homes.

11. Redevelopment projects.

Single-family homes are not deemed planning priority projects unless they create, add or replace at least ten thousand square feet of impervious surface area.

"Project" means all development, redevelopment, and land disturbing activities. The term is not limited to "project" as defined under CEQA.

"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" (as defined in the municipal NPDES permit) into which waste or pollutants are or might be discharged.

"Redevelopment" means land disturbing activity that results in the creation, addition, or replacement of five thousand square feet or more of impervious surface area on an already developed site. Redevelopment includes, but is not limited to: the expansion of a building footprint; addition or replacement of a structure; replacement of impervious surface area that is not part of routine maintenance activity; and land disturbing activity 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.

"Regional board" means the appointed members of the California Regional Water Quality Control Board, Los Angeles Region.

"Restaurant" means a facility that sells prepared foods and drinks for consumption, including stationary lunch counters and refreshment stands selling prepared foods and drinks for immediate consumption.

"Retail gasoline outlet" means any facility engaged in selling gasoline and lubricating oils.

"Routine maintenance" includes, but is not limited to, projects conducted to:

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

2. Perform as needed 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. Update existing lines and facilities to comply with applicable codes, standards, and regulations regardless if such projects result in increased capacity; and/or

5. Repair leaks.

Routine maintenance does not include construction of new lines (those that are not associated with existing facilities and are not part of a project to update or replace existing lines) or facilities resulting from compliance with applicable codes, standards and regulations.

"Runoff" means the portion of rainfall or irrigation water or other water activities also known as dry-weather flows that flow across the ground surface arid eventually to receiving waters. Runoff can pick up pollutants from the air or the land and carry them to receiving waters.

"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.

"State board" or "SWRCB" means the State Water Resources Control Board of the California Environmental Protection Agency.

"Storm drain system" means any facility or any parts of the facility, including streets, gutters, conduits, natural or artificial drains, channels and watercourse that are used for the purpose of collecting, storing, transporting or disposing of stormwater and are located within the city.

"Storm water" or "stormwater" means runoff and drainage related to precipitation events.

"Storm water quality management program" means the Los Angeles countywide storm water quality management program, which includes descriptions of programs, collectively developed by the permittees in accordance with provisions of the NPDES permit, to comply with applicable federal land state law, as the same is amended from time to time.

"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.

(Ord. 2245 § 1 (part), 2002)

(Ord. No. 2361, § 2, 6-25-2014)

A. No person shall cause or allow an illicit discharge to enter the municipal storm water system.

B. No person shall place, dump, dispose, litter, accumulate, maintain, discharge, or cause to enter into the MS4 any pollutant or any foreign object such as batteries, tires, waste receptacles, yard debris, refuse, rubbish, food waste, chemicals, animal waste or oil cans—which are also considered illicit discharges.

C. Any person causing an illicit discharge to the MS4 may be required to pay for the cost of clean-up and remediation.

D. Any owner of any private property from which a non-storm water discharge is observed may be required to pay for the cost of collecting and analyzing the discharge to determine if it is an illicit discharge.

E. Discharges identified in Part III.A of the municipal NPDES permit are considered exempt or conditionally exempt illicit discharges.

(Ord. 2245 § 1 (part), 2002)

(Ord. No. 2361, § 3, 6-25-2014)

A. No person shall maintain or intentionally use a connection that operates to convey an illicit discharge to the municipal storm water system.

B. Upon discovery of an illicit connection, the person owning or operating such connection shall either remove it or render it incapable of conveying an illicit discharge.

C. If any person fails to eliminate an illicit connection after being called upon by the city to do so, the city manager or the director of public works or his/her designee(s), shall impose appropriate measures to remove or disable the illicit connection and may recover the costs from the owner of such illicit connection.

(Ord. 2245 § 1 (part), 2002)

A. No person shall cause or threaten to cause the discharge of pollutants to the MS4 by exposing such pollutants to storm water runoff.

(Ord. 2245 § 1 (part), 2002)

A. Subject commercial facilities shall implement BMPs prescribed by the regional board or its Executive Officer, through programs or actions made pursuant to the municipal NPDES permit, as called for more particularly in the city's storm water quality management program, or any revisions made thereto.

(Ord. 2245 § 1 (part), 2002)

A. It shall be a violation of this chapter for any industry in the city that is subject to waste discharge requirements specified in the SWRCB Water Quality Order No. 97-03-DWQ, Permit No. CAS00001, any revision or a re-issuance thereof, to operate without a general industrial activities storm water NPDES permit.

B. Industries that require a general industrial activities storm water NPDES permit shall retain on-site the following documents: (i) a copy of the notice of intent for general permit to discharge storm water associated with industrial activity; (ii) a waste discharge identification number issued by the SWRCB; and/or (iii) a storm water pollution prevention plan and monitoring program plan.

C. Any industry in the city requiring a general industrial activities storm water NPDES permit shall, upon reasonable request from a duly authorized officer of the city, provide any of the documents described in subsection B of this section.

(Ord. 2245 § 1 (part), 2002)

A. Industrial facilities not subject to the general industrial activities storm water NPDES permit but are subject to pollution control requirements under the municipal NPDES permit, shall implement BMPs prescribed by the regional board or its Executive Officer, through programs or actions made pursuant to the municipal NPDES permit.

(Ord. 2245 § 1 (part), 2002)

A. No person shall be granted a grading permit or shall commence or continue any construction activity that is subject to an general construction activity storm water NPDES permit without showing proof of having applied for such permit.

B. Any person engaged in a construction activity requiring a general construction activity storm water NPDES permit construction permit shall retain at the construction site the following documents: (i) a copy of the notice of intent to comply with terms of the general permit to discharge water associated with construction activity; (ii) a waste discharge identification number issued by the SWRCB; (iii) a storm water pollution prevention plan and monitoring program plan for the construction activity requiring the construction permit; and (iv) records of all inspections, compliance and non-compliance reports, evidence of self-inspection and good housekeeping practices.

C. Any person engaged in a construction activity in the city requiring an NPDES general construction storm water activity permit shall, upon reasonable request from a duly authorized officer of the city, provide any of the documents specified in subsection B of this section and shall retain said documents for at least three years after completion of construction.

(Ord. 2245 § 1 (part), 2002)

A. Any person engaged in a construction activity that is not subject to the general construction storm water activity NPDES permit, but is subject to the municipal NPDES permit, shall comply with all requirements specified in the storm water management quality program, including any revisions made thereto.

(Ord. 2245 § 1 (part), 2002)

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 municipal NPDES permit, 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 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 ten thousand square feet of impervious surface area.

(2) Industrial parks ten thousand square feet or more of surface area.

(3) Commercial malls ten thousand square feet or more of surface area.

(4) Retail gasoline outlets with five thousand square feet or more of surface area.

(5) Restaurants (Standard Industrial Classification (SIC) of 5812) with five thousand square feet or more of surface area.

(6) Parking lots with five thousand square feet or more of impervious surface area, or with twenty-five or more parking spaces.

(7) Streets and roads construction projects with construction costs greater than five hundred thousand dollars and add at least ten thousand 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, 7532-7534 and 7536-7539) 5,000 square feet or more of surface area.

(9) Projects located in or directly adjacent to, or discharging directly to an environmentally sensitive area (ESA) (as defined in California Public Resources Code Section 30107.5), 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 square feet or more of impervious surface area

(10) Single-family hillside homes.

(11) Redevelopment projects.

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

b. Where redevelopment results in an alteration to more than fifty percent 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 fifty percent 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 (as defined in Section 8.36.020) 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 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 ten thousand square feet of impervious surface area.

D. Effective Date. The planning and land development requirements contained in Section 7 of Part VI.D of the municipal NPDES permit shall become effective ninety days from the adoption of the order (February 6, 2013). 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 ninety days of adoption of the order. Projects that have been deemed complete within ninety days of adoption of the order are not subject to the requirements [in] 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) A new 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 projects with construction costs greater than five hundred thousand and add at least ten thousand 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:

a. Retain stormwater runoff onsite for the stormwater quality design volume (SWQDv) defined as the runoff from:

i. The eighty-fifth percentile twenty-four-hour runoff event as determined from the Los Angeles County 85th percentile precipitation isohyetal map; or

ii. The volume of runoff produced from a three-quarter-inch, twenty-four-hour rain event, whichever is greater.

b. Minimize hydromodification impacts to natural drainage systems as defined in Order No. R4-2012-0175.

c. To demonstrate technical infeasibility, the project applicant must demonstrate 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 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 onsite.

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

iii. Locations within one hundred feet of a groundwater well used for drinking water;

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

v. Locations with potential geotechnical hazards;

vi. Smart growth, infill, specific plans, 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 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 Order No. R4-2012-0175. 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 Montebello to determine eligibility.

e. 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 Order No. R4-2012-0175. Flow-through BMPs may be used to treat the remaining SWQDv and must be sized based on a rainfall intensity of:

i. 0.2 inches 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. 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 and satisfying the standards and requirements of this chapter for the entire site during the first phase, and (b) implementing the standards and requirements of this chapter 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. 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 of 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.

G. Additional Requirements. The site for projects not classified with general applicability listed in paragraph C of this section, but resulting in the creation or addition or replacement of five hundred square feet or more of impervious surface area shall be designed to control pollutants, pollutant loads, and runoff volume per requirements listed herein.

(Ord. 2245 § 1 (part), 2002)

(Ord. No. 2361, § 4, 6-25-2014)

A. The director of public works, the city engineer and duly authorized representatives thereof, are hereby authorized and directed to enforce all provisions of this chapter.

B. Nothing in this chapter precludes a local authority from using regular full-time employees to enforce this chapter. This authority shall be in addition to the authority granted to police and code enforcement officers.

C. Fees to be charged for plan checking, inspection, enforcement and any other activities carried out by the city shall be specified by resolution of the city council.

(Ord. 2245 § 1 (part), 2002)

A. The director of public works, city engineer or duly authorized designee thereof, may, on twenty-four hour oral or written notice, unless exigent circumstances justify a shorter time period, enter upon and inspect any private premises for the purposes of verifying compliance with the terms of this chapter and perform any duty imposed upon the officer by this chapter, provided that:

1. If such building or premises be occupied, he or she shall first present proper credentials and request entry.

2. If such building or premises be unoccupied, he or she shall first make a reasonable effort to locate the owner or occupant of the building or premises and request entry. In the event that a request for entry is refused, the officer is hereby empowered to seek assistance from any court of competent jurisdiction in obtaining such entry.

B. Such inspection may include, but is not limited to:

1. Identifying products produced, processes conducted, chemicals and materials used, stored or maintained on the subject premises;

2. Identifying points of discharge of all waste water, non-storm water, processed water system and pollutants;

3. Investigating the natural slope of the premises, including drainage patterns and man-made conveyance systems;

4. Establishing location of all points of discharge from the premises, whether by surface runoff or through a storm drain system;

5. Locating any illicit connection or illicit discharge;

6. Inspecting a vehicle, truck, trailer, tank or other mobile equipment;

7. Inspecting all records of the owner or occupant of public or private property relating to chemicals or processes presently or previously stored or occurring on the property, including material and/or chemical inventories, facilities maps or schematics and diagrams, material safety data sheets, hazardous waste manifests, business plans, pollution prevention plans, state general permits, and any and all records relating to illicit connections, illicit discharges, or any other source of contribution or potential contribution of pollutants to the municipal storm drain system;

8. Inspecting, sampling and testing any area runoff, soils area (including groundwater testing), process discharge, materials with any waste storage area (including any container contents), and/or treatment system discharges for the purpose of determining the potential for contribution of pollutants into the municipal storm drain system;

9. Inspecting the integrity of all storm drain and sanitary sewer systems and any connection to other pipelines on the property, including the use of dye and smoke tests, video surveys, photographs or videotapes, and the taking of measurements, drawings, or any other records reasonably necessary to document conditions as they exist on the premises;

10. Installing and maintaining of monitoring devices for the purpose of measuring any discharge, or potential source of discharge, to the municipal storm drain system;

11. Evaluating compliance with this chapter or the Clean Water Act.

(Ord. 2245 § 1 (part), 2002)

A. The director of public works, city engineer or duly authorized representatives may serve notice of violation upon a person owning or occupying a premises, describing the violations and requiring prompt correction thereof, when:

1. Pollutants or potential pollutants are being maintained, discharged or deposited in such a manner as to create, or if allowed to continue will create, any one or more of the following conditions, (a) a public nuisance, (b) a menace to the public safety, (c) pollution of underground or surface waters, (d) damage to any public sewer, municipal storm sewer system, or public or private property.

2. The person has failed to respond or comply with a previous notice of violation within the time period specified in the notice.

B. Failure to comply with a duly served notice of violation shall constitute a willful violation of this chapter.

C. The city manager, director of public works, or duly authorized representatives may serve a cease and desist order upon a person owning or occupying a premises, requiring the person to immediately:

1. Discontinue any illicit discharge, including process water, wastewater or pollutant discharge to the MS4.

2. Block or divert any flow of water from the property where the flow is occurring in violation of any provision of this chapter.

3. Discontinue any other violation of this chapter.

The cease and desist order may contain terms and conditions or other provisions to ensure compliance with this chapter.

D. Any person violating any provision of this chapter is guilty of a misdemeanor, and upon conviction is punishable by fine not exceeding one thousand dollars or by imprisonment in the county jail for a period not exceeding six months, or by both such fine and imprisonment. As a part of any sentence or other penalty imposed or the award of any damage, the court may also order that restitution be paid to the city or any injured person, or, in the case of a violator who is a minor, by the minor's parent or lawfully designated guardian or custodian. Restitution may include the amount of any reward.

E. The city attorney is also authorized to file in a court of competent jurisdiction a civil action seeking an injunction against any violation or threatened or continuing violation of this chapter. Any temporary, preliminary or permanent injunction issued pursuant hereto may include an order for reimbursement to the city for all costs incurred in enforcing this chapter, including costs of inspection, investigation, monitoring, treatment, abatement, removal or remediation undertaken by or at the expense of the city, and may include all legal expenses and fees and any or all costs incurred relating to the restoration or remediation of the environment.

F. Each separate discharge in violation of this chapter and each day a violation described in this chapter exists without correction, shall constitute a new and separate violation punishable as a separate criminal offense and/or civil violation.

G. Any person who violates any provision of this chapter, any provision of any permit issued pursuant to this chapter, or who discharges waste or wastewater which causes pollution, or who violates any cease and desist order, prohibition, or effluent limitation, also may be in violation of the Federal Clean Water Act and/or Porter-Cologne Act and may be subject to the sanctions of those acts including civil and criminal penalties. In addition, the city attorney is authorized to file a citizen's suit pursuant to the Clean Water Act, seeking penalties, damages and orders compelling compliance and appropriate relief.

H. The penalties and remedies established by this chapter shall be cumulative.

I. Any person violating the provisions of this chapter shall reimburse the city for any and all costs incurred by the city in responding to, investigating, assessing, monitoring, treating, cleaning, removing, or remediating any illicit discharge or pollutant from the municipal storm drain system; rectifying any illicit connection; or remediating any violation of this chapter. Such costs to be paid to the city include all administrative expenses and all legal expenses, including costs and attorneys' fees, in obtaining compliance, and in litigation including all costs and attorneys' fees on any appeal. The costs to be recovered pursuant to this section shall be recoverable from any and all persons violating this chapter.

J. The city shall have full power and authority to take any necessary precautions including, but not limited to, decontamination, storm drain closure, packaging, diking, and transportation of materials, in order to protect life, protect property, or prevent an imminent hazard to the public's health, safety or welfare. In the event any violation of this chapter constitutes an imminent danger to public health, safety, or the environment, the director of public works, city engineer or any authorized agent thereof, may enter upon the premises from which the violation emanates, abate the violation and danger created to the public safety or the environment, and restore any premises affected by the alleged violation, without notice to or consent from the owner or occupant of the premises. An imminent danger shall include but is not limited to exigent circumstances created by the discharge of pollutants, where such discharge presents a significant and immediate threat to the public health or safety, or the environment.

K. Notwithstanding any other provisions herein, violations of this chapter may further be deemed to be a public nuisance that may be abated by administrative or civil or criminal action in accordance with the terms and provisions of this code and state law. All costs and fees incurred by the city as a result of any violation of this chapter which constitute a nuisance, including all administrative fees and expenses and legal fees and expenses, shall become a lien against the subject premises from which the nuisance emanated and a personal obligation against the owner, in accordance with Government Code Sections 38773.1 and 38773.5. The owner of record of the premises subject to any lien shall receive notice of the lien prior to recording, as required by Government Code Section 38773.1. The city attorney is authorized to collect nuisance abatement costs and enforce a nuisance lien in an action brought for money judgment, or by delivery to the county assessor of a special assessment against the premises in accordance with the conditions and requirements of Government Code Section 38773.5.

L. Any remedies provided to the city in this chapter are not exclusive, and the city may utilize any and all other remedies as otherwise provided by law.

M. Compliance by any person or entity with the provision of this chapter shall not relieve any such person or entity from complying with other applicable local, state or federal statutory or regulatory requirements.

(Ord. 2245 § 1 (part), 2002)