Chapter 1014-4 — APPLICATION

Sections:

1014-4.002 - Construction and application.

For the unincorporated area, this division shall be construed in a manner consistent with the requirements of the Federal Clean Water Act and the Porter-Cologne Water Quality Control Act and amendments thereto, applicable implementing regulations, and the county's NPDES permits.

(Ord. 2005-01 § 3, 96-21 § 3).

1014-4.004 - Stormwater control plan required.

(a)

Effective February 15, 2005, the following developments are subject to the requirements of provision C.3 of the county's NPDES permits:

(1)

Any development that creates one acre (forty-three thousand five hundred sixty square feet) or more of impervious surface, including roof areas, streets and sidewalks. Excluded from this category is the construction of one single-family home that is not part of a larger plan of development, provided that the home has appropriate pollutant source control and site design measures and uses landscaping to appropriately treat runoff from roof and house-associated impervious surfaces.

(2)

Streets, roads, highways and freeways under the county's jurisdiction that create one acre (forty-three thousand five hundred sixty square feet) or more of new impervious surface. Excluded from this category are sidewalks, bicycle lanes, trails, bridge accessories, guardrails and landscape features.

(3)

Developments on previously developed sites that result in the addition or replacement of a combined total of one acre (forty-three thousand five hundred sixty square feet) or more of impervious surfaces. Excluded from this category are interior remodels and routine maintenance or repair. Excluded routine maintenance or repair includes roof or exterior surface replacement, pavement resurfacing, repaving and road pavement structural section rehabilitation within the existing footprint, and any other reconstruction work within a public street or road right-of-way where both sides of that right-of-way are developed.

(b)

Effective August 15, 2006, the following developments are subject to the requirements of provision C.3 of the county's NPDES permits:

(1)

Any development that creates ten thousand square feet or more of impervious surface, including roof areas, streets and sidewalks. Excluded from this category is the construction of one single-family home that is not part of a larger plan of development.

(2)

Streets, roads, highways and freeways under the county's jurisdiction that create ten thousand square feet or more of new impervious surface. Excluded from this category are sidewalks, bicycle lanes, trails, bridge accessories, guardrails and landscape features.

(3)

Developments on previously developed sites that result in the addition or replacement of a combined total of ten thousand square feet or more of impervious surfaces. Excluded from this category are interior remodels and routine maintenance or repair. Excluded routine maintenance or repair includes roof or exterior surface replacement, pavement resurfacing, repaving and road pavement structural section rehabilitation within the existing footprint, and any other reconstruction work within a public street or road right-of-way where both sides of that right-of-way are developed.

(c)

Effective July 1, 2023, the following developments are subject to the requirements of provision C.3 of the county's NPDES permits:

(1)

Any new development project on a previously undeveloped site that creates five thousand square feet or more of impervious surface, including but not limited to roof areas, streets and sidewalks, except for single- family home projects that meet the following criteria:

(A)

Involve construction of only one single-family home or its appurtenances, (B) create or replace less than ten thousand square feet of impervious surface, and (C) are not part of a larger development or redevelopment plan regulated under this chapter.

(2)

Any development project on a previously developed site that creates or replaces five thousand square feet or more of impervious surface, except for the following:

(A)

Single-family home projects that (i) involve construction of only one single-family home or its appurtenances, (ii) create or replace less than ten thousand square feet of impervious surface, and (iii) are not part of a larger development or redevelopment plan regulated under this chapter;

(B)

Interior remodels;

(C)

Routine maintenance or repair such as roof or exterior wall surface replacement;

(D)

Public road and trail projects;

(E)

Public works projects that create or replace less than five thousand contiguous square feet of impervious surface; and

(F)

The following pavement maintenance practices: Pothole and square cut patching; overlaying existing asphalt or concrete pavement with asphalt or concrete without expanding the area of coverage; shoulder grading; reshaping or regrading drainage systems; crack sealing; pavement preservation activities that do not expand the road prism; upgrading from a bituminous surface treatment with an overlay of asphalt or

concrete without expanding the area of coverage; applying a bituminous surface treatment to existing asphalt or concrete pavement without expanding the area of coverage; layering gravel over an existing gravel road without expanding the area of coverage; and vegetation maintenance. If a project consists of any of a combination of any exempt pavement maintenance practices and non-exempt pavement maintenance practices, the part or parts of the project that are non-exempt will be evaluated as a regulated project.

(3)

Construction of new streets or roads (including sidewalks and bicycle lanes), widening of existing streets or roads with additional traffic lanes, and construction of impervious trails that are ten feet or more in width or located within fifty feet of the top of a creek bank, that are under the county's jurisdiction and create five thousand square feet or more of newly constructed contiguous impervious surface, except for the following:

(A)

Sidewalks built as part of new streets or roads and that direct stormwater runoff to adjacent vegetated areas;

(B)

Bicycle lanes built as part of, but that are not hydraulically connected to, new streets or roads and that direct stormwater to adjacent vegetated areas;

(C)

Impervious trails that direct stormwater to adjacent vegetated or other non- erodible permeable areas that are at least half as large as the contributing impervious surface area; and

(D)

Sidewalks, bicycle lanes, or trails constructed as pervious pavement systems;

(E)

State of California highway projects and associated facilities.

(4)

Public and other road projects under the county's jurisdiction that involve the reconstruction of streets or roads and that create or replace one contiguous acre or more of impervious surface, excluding the pavement maintenance practices described in subsection (c)(2)(F); and

(5)

Single-family home projects that involve construction of only one home or its appurtenances, including the addition of an accessory dwelling unit on a parcel with one single-family home, and that create or replace ten thousand square feet or more of impervious surface and are not part of a larger development or redevelopment plan.

(d)

Every application for a development, including but not limited to a rezoning, tentative map, vesting tentative map, parcel map, conditional use permit, variance, development plan, site development permit, design review, or building permit, that is subject to development runoff requirements in the county's NPDES permits, shall comply with all requirements of the county's NPDES permits and be accompanied by a stormwater control plan that meets the criteria in the guidebook. Applications will not be deemed complete for processing until after the stormwater control plan has been reviewed and approved for completeness.

(e)

For any development where a stormwater control plan is required, implementation of an approved stormwater control plan and submittal of an approved stormwater facilities operation and maintenance plan is a condition precedent to the issuance of a certificate of occupancy or final inspection permit.

(f)

All stormwater management facilities implemented pursuant to this subsection shall be designed, constructed, maintained, and operated according to all requirements of the county's NPDES permits, the guidebook, and the approved stormwater facilities operation and maintenance plan. The person(s) or organization(s) responsible for maintenance shall be designated in the plan. Unless a different time period is provided for in the plan, those responsible for maintenance shall inspect the stormwater management facility at least annually. The plan also shall describe how the maintenance costs will be funded. Upon the failure of a responsible person to maintain a stormwater management facility in accordance with this chapter or the plan, the county may use any of the remedies provided in Chapter 1014-6 or otherwise available in law or equity.

(g)

If a stormwater control plan requires the construction of stormwater management facilities (structural BMPs), the property owner must provide recorded covenants, easements, or offers of dedication allowing access for inspection and maintenance of those facilities by the county, the Contra Costa Mosquito and Vector Control District, the regional water quality control boards, the fire protection districts, the sanitary or sanitation districts, the municipal improvement districts, the reclamation districts, and other public agencies that have jurisdiction over the property.

(h)

Notwithstanding any other provision in this division, a development is exempt from a specific requirement in provision C.3 of the county's NPDES permits if the county's NPDES permits either:

(1)

Expressly exempt the development from the requirement; or

(2)

Authorize the county to grant an exemption from the requirement, and the director grants an exemption from the requirement to the development in accordance with that authority.

(Ord. No. 2025-01, § III, 2-4-25; Ord. 2005-01 § 3, 96-21 § 3).

1014-4.006 - Prohibited discharges.

(a)

The release of illicit discharges to the county stormwater system is prohibited.

(b)

The following unpolluted discharges are exempt from the prohibition set forth in subsection (a) of this section: Flows from riparian habitats or wetlands; diverted stream flows; flows from natural springs; rising ground waters; uncontaminated groundwater infiltration; single family home pumped groundwater; discharges from single family home foundation drains; water from single family home crawl space pumps or footing drains; pumped groundwater from drinking water aquifers (except for well development); and discharges conforming to individual or general NPDES permits.

(c)

The following discharges are exempt from the prohibition set forth in subsection (a) of this section to the extent that the discharges are exempt under the county's NPDES permits: Uncontaminated pumped groundwater; discharges from foundation drains; water from crawl space pumps or footing drains; air conditioning condensate; irrigation water; landscape irrigation; lawn or garden watering; individual residential car washing; discharges of water and foam from emergency firefighting activities; and dechlorinated discharges from swimming pool, hot tubs, spas and fountains.

(Ord. No. 2025-01, § IV, 2-4-25; Ord. 2005-01 § 3, 96-21 § 3).

1014-4.008 - Discharge in violation of NPDES permit.

Any discharge that would result in or contribute to a violation of the county's NPDES permits, either separately considered or when combined with other discharges, is prohibited. Liability for any such discharge is the responsibility of the person(s) causing or responsible for the discharge. To the extent allowed by law, such person(s) or permitee(s) shall defend, indemnify and hold harmless the county, its officers, employees, and agents in any administrative or judicial enforcement action.

(Ord. 2005-01 § 3, 96-21 § 3).

1014-4.010 - Unlawful discharge and unlawful connections.

(a)

It is unlawful to establish, use, maintain or continue unauthorized drainage connections to the county's stormwater system.

(b)

It is unlawful to commence or continue any unauthorized discharge to the county's stormwater system.

(Ord. 2005-01 § 3, 96-21 § 3).

1014-4.012 - Reduction of pollutants in stormwater.

(a)

Generally. Any person engaging in activities that may result in pollutants entering the county's stormwater system shall undertake all practicable measures to reduce such pollutants. Examples of such activities include the ownership and use of premises that may be a source of pollutants, such as parking lots, gasoline stations, industrial facilities, business enterprises and dwelling units.

(b)

Litter. No person shall throw, deposit, leave, keep or permit to be thrown, deposited, placed, left or maintained, any refuse, rubbish, garbage or other discarded or abandoned objects, articles or other litter in or upon any street, alley, sidewalk, business place, creek, stormwater system, fountain, pool, lake, stream, river or any other body of water, or upon any public or private parcel of land, except in containers or in lawfully established waste disposal facilities.

(c)

Sidewalks. The occupant or tenant, or in the absence of occupant or tenant, the owner or proprietor of any real property in front of which there is a paved sidewalk, shall maintain the sidewalk free of dirt or litter to the maximum extent practicable. Sweepings from the sidewalk shall not be swept or otherwise made or allowed to go into the gutter or roadway, but shall be disposed of in receptacles maintained as required for the disposal of solid waste.

(d)

Parking Lots, Paved Areas and Related Stormwater Systems. Persons owning, operating or maintaining a paved parking lot, a paved area of a gasoline station, a paved private street or road, or a related stormwater system shall clean those premises as frequently and thoroughly as practicable in a manner that does not result in the discharge of pollutants to the county's stormwater system.

(e)

Best Management Practices for New Developments and Redevelopments. All construction contractors performing work in the unincorporated area of the county shall conform to the requirements of the California Stormwater Quality Association (CASQA) Stormwater Best Management Practice Handbooks for Construction Activities and New Development and Redevelopment, the Association of Bay Area Governments (ABAG) Manual of Standards for Erosion and Sediment Control Measures, the county's grading ordinance (Division 716 of the ordinance code), the ordinance codified in this chapter, and other generally accepted engineering practices for erosion control as required by the director. The director may establish controls on the volume and rate of stormwater runoff from new developments and redevelopment as may be appropriate to minimize the discharge and transport of pollutants.

(f)

Notification of Intent and Compliance with General Permits. Each industrial discharger, 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 regional water quality control board (San Francisco Bay Region or Central Valley Region), shall provide the notice of intent, comply with, and undertake all other activities required by any general stormwater permit applicable to such dischargers. Each discharger identified in an individual NPDES permit relating to stormwater discharges shall comply with and undertake all activities required by the permit.

(g)

Compliance with Best Management Practices. Where best management practices, guidelines or requirements have been adopted by any federal, state, regional, city or county agency, for any activity or operation of premises that may cause or contribute to stormwater discharges prohibited pursuant to Section 1014-4.006, every person who undertakes such activity, or operation, or who owns or operates such premises, shall comply with such guidelines or requirements.

(h)

Stormwater Pollution Prevention Plan. The director may require any business or utility in unincorporated areas of the county that is engaged in activities that may result in runoff pollutants or discharges prohibited by Section 1014-4.006 to develop and implement a stormwater pollution prevention plan, which must include an employee training program. Business activities which may require a stormwater pollution prevention plan include maintenance, storage, manufacturing, assembly, equipment operations, vehicle loading, fueling, vehicle maintenance, food handling or processing, or cleanup procedures that are carried out partially or wholly out of doors.

(i)

Coordination with Hazardous Material Release Response and Inventory Plans. Any business required by Chapter 6.95 of Division 20 of the Health and Safety Code (commencing with Section 25500) to submit a business plan or a risk management and prevention program (RMPP), or both, or any owner or operator of a hazardous water facility required by Chapter 15 of Division 4.5 of Title 22 of the California Code of Regulations to maintain a contingency plan, shall include in that plan or program provision for compliance with this division, including discharges prohibited under Section 1014-4.006 and the requirement to reduce the release of pollutants to the maximum extent practicable.

(j)

Coordination with Vector Control Plan. All design, construction, operation and maintenance of stormwater management facilities shall conform to the requirements of the Contra Costa Clean Water Program's Vector Control Plan, as approved by a regional water quality control board.

(Ord. No. 2005-01 § 3).

1014-4.014 - Compliance certificates for stormwater management facilities.

Each year, the public works department will send notice to each person who owns premises containing stormwater management facilities. That person will be required to complete and submit a valid operation and maintenance certificate certifying to the inspection of and the proper operation and maintenance of the

treatment measures and other appropriate source control and site design measures at that time and during the preceding year.

(Ord. 2005-01 § 3).

1014-4.016 - Authority to inspect.

(a)

Generally. Routine or area inspections may be performed as deemed necessary to carry out the objectives of this division, including, but not limited to, random sampling, sampling in areas with evidence of stormwater contamination, evidence of the discharges prohibited under Section 1014-4.006 to the stormwater system, or similar factors. Inspections may also be conducted in conjunction with routine or scheduled inspections conducted by county departments, including Contra Costa Health Services, and other public agencies or special districts, including but not limited to sanitary districts, sanitation districts, fire protection districts, the Contra Costa Mosquito and Vector Control District, regional water quality control boards, reclamation districts and municipal improvement districts.

(b)

Authority to Sample and Establish Sampling Devices. With the consent of the owner or occupant, or pursuant to a search or inspection warrant, any authorized county employee may use on any property such devices as are necessary to conduct sampling or metering operations. During all authorized inspections, the authorized county employee may take any sample deemed necessary to aid in the pursuit of the inquiry or in the recordation of the activities on site.

(c)

Notification of Spills.

(1)

All persons in charge of a premises or responsible for emergency response for a premises have a responsibility to train premises personnel and maintain notification procedures to ensure that immediate notification is provided to the county of any suspected, confirmed or unconfirmed release of material, pollutants, or waste that creates a risk of discharges prohibited under Section 1014-4.006 into the county stormwater system.

(2)

As soon as any person in charge of a premises or responsible for emergency response for the premises has knowledge of any suspected, confirmed or unconfirmed release of discharges prohibited under Section 1014-4.006 entering the county stormwater system, such person shall take all necessary steps to ensure the discovery, containment, and clean up of such release, and shall promptly notify the director of the occurrences by telephone. This notification requirement is in addition to and not in lieu of other required notifications.

(d)

Requirement to Test or Monitor. Any authorized county employee may require that any person engaged in any activity that may cause or contribute to discharges prohibited under Section 1014-4.006, to undertake such monitoring activities or analysis, or both, and furnish such reports as the employee may specify. The burden of the requirements imposed, including costs, of these activities, analysis and reports shall bear a reasonable relationship to the need for the monitoring, analysis and reports and the benefits to be obtained. The recipient of such request shall undertake and provide the monitoring, analysis and reports required in a timely manner.

(e)

Right of Entry. Whenever necessary to make an inspection to enforce any of the provisions of this division, or whenever the director has reasonable cause to believe that there exists in any building or upon any premises any condition that makes such building or premises in violation of this division, the director may enter such building or premises at all reasonable times to inspect the same or to perform any duty authorized by this division, with consent of the owner or occupant. If consent is refused, or if the owner or occupant cannot be located, the director may proceed pursuant to a search or inspection warrant.

(Ord. 2005-01 § 3, 96-21 § 3).