Santa Clara County Municipal Code Ch. V Post Construction Stormwater Pollution Prevention Requirements

Sec. B11.5-17. - Purpose of chapter.

The purpose of this chapter is to provide minimum requirements designed to control, reduce, and prevent the discharge of pollutants into the stormwater system of Santa Clara County from public and private land development projects, in compliance with applicable provisions of the Federal Clean Water Act and the most recently adopted version of the NPDES Municipal Stormwater Discharge Phase I and II Permit (NPDES permit) issued to the County of Santa Clara by the San Francisco Bay and Central Coast Regional Water Quality Control Board, based on which watershed the project is located in. The provisions of the applicable permits are hereby incorporated by reference.

It is unlawful for any person or persons to develop or redevelop property, or construct, remodel, rebuild, alter, modify or expand any structure within the unincorporated areas of Santa Clara County in any manner which fails to comply with the requirements of this chapter and the County's NPDES stormwater discharge permit.

(Ord. No. NS-517.84, 6-25-13)

Sec. B11.5-18. - Project application or building permit expiration.

When a project application or building permit has expired, even when previously deemed complete, any re-application or new application must conform to the provisions of this chapter which are in effect at the time of re-application. This section shall not apply to applications that are extended under the provisions of a county ordinance, prior to the land use application expiration date.

(Ord. No. NS-517.84, 6-25-13)

Sec. B11.5-19. - Stormwater project criteria.

Stormwater requirements are determined based on which watershed the project drains into (See Watershed Map, on file with the Department of Planning and Development) and the most recently adopted NPDES permit for the applicable watershed. In addition, the type of development and/or redevelopment project and the amount of new and/or replaced impervious surface area planned for the project are also used to determine stormwater requirements.

(Ord. No. NS-517.84, 6-25-13)

Sec. B11.5-20. - Project requirements for new development or redevelopment projects.

A. Clean Water Questionnaire (a copy of the questionnaire is available from the Department of Planning and Development) shall be submitted and approved by the Office of Land Development Engineering or Building Inspection as part of the following:

1. Land Use Approval Application Submittal: or

2. Building Permit Applications (unless the project was previously submitted and approved by the Office of Land Development Engineering).

B. Projects subject to stormwater requirements shall not receive a grading, drainage, building, stormwater or other permit until the new or redevelopment project has demonstrated compliance with the applicable NPDES Permit and received approval from the Office of Land Development Engineering or Building Inspection. Compliance shall be demonstrated by including the following as part of the plans and other related documentation, as applicable and determined by the Office of Land Development Engineering or Building Inspection:

1. Site design measures;

2. Source control measures;

3. Permanent stormwater treatment measures/LID treatment measures;

4. Hydromodification management measures;

5. Sizing calculations for stormwater treatment and/or hydromodification modification measures;

6. Operation and Maintenance Agreement:

a. Including maintenance plans for stormwater treatment and/or hydromodification management measures and responsible party.

b. Map showing the location of stormwater treatment and/or hydromodification management measures.

7. Stormwater Pollution Prevention Plan or an erosion/pollution control plan showing the BMPs set forth in section B11.5-16.A; and

8. Other information as may be required.

C. Stormwater permit process shall follow the permitting process of the Drainage Permit as outlined in Division C12 of the County Ordinance Code.

D. Construction of the approved plans shall be inspected and approved by the County.

(Ord. No. NS-517.84, 6-25-13)

Sec. B11.5-21. - Limitations on use of infiltration devices.

Any permanent stormwater pollution prevention measure, which functions primarily as an infiltration device, shall not cause or contribute to the degradation of groundwater quality at the project site and shall comply with the requirements in the most recently adopted version of the NPDES permit.

(Ord. No. NS-517.84, 6-25-13)

Sec. B11.5-22. - Alternative compliance.

Following approval from the Director of Planning and Development or designee, a project may use alternative compliance options allowed under the most recently adopted NPDES permit to comply with stormwater requirements. All projects using alternative compliance shall demonstrate compliance with the NPDES permit as part of the plans and other related documentation as required in [Section] B11.5-20.

(Ord. No. NS-517.84, 6-25-13)

Sec. B11.5-23. - Operation and maintenance responsibility for stormwater quality BMPs and HMP measures for all regulated projects.

A. For the life of the project, all stormwater treatment, LID and/or HMP measures shall be operated and maintained in good condition and promptly repaired by the property owner(s), a Homeowners' Association, or other legal entity approved by the County. Any repairs or restoration and maintenance shall be in accordance with the original County-approved plans.

B. Prior to the issuance of any building or grading permit for a Regulated project, the owner(s) of the site shall enter into a formal written stormwater BMP operation and maintenance agreement with the County. The County shall record this agreement with reference to the property or properties involved with the Clerk-Recorder of the County of Santa Clara, and it shall be binding on all subsequent owners of land served by the required stormwater treatment BMPs. The agreement shall require the following:

1. That the BMPs not be modified without the permission of the Development Services Office of the County Department of Planning and Development, and that BMP maintenance activities not alter the design or function of the facility from the original approved plan, unless approved by the Development Services Office prior to the commencement of the proposed modification or maintenance activity.

2. That the County shall perform operation and maintenance inspections of installed stormwater quality BMPs and hydromodification management BMPs, as specified in the most recent adopted version of the NPDES Permit.

Property owners, Homeowners' Association or other legal entity approved by the County shall be responsible for inspecting, at least once a year prior to the rainy season unless otherwise directed by the County, all permanent stormwater quality BMP measures and Hydromodification Management BMP measures to ensure all systems are properly working.

C. The property owner shall allow the County to inspect facilities to verify maintenance and to require maintenance/repair when necessary.

D. Failure to allow inspection of permanent stormwater pollution prevention measures shall be subject to enforcement actions as described in [Division] B11.5, Chapter III.

(Ord. No. NS-517.84, 6-25-13)

Sec. B11.5-24. - Failure to maintain stormwater treatment and HMP facilities.

Failure to maintain permanent stormwater pollution prevention measures shall be subject to enforcement actions as described in [Division] B11.5, Chapter III: Enforcement. In addition, if the property owner fails or refuses to meet the requirements of the stormwater BMP operation and maintenance agreement. The County will invoice the owner(s) of the property for the cost of repair work and any administrative costs, pursuant to Section B11.5-12.

(Ord. No. NS-517.84, 6-25-13)