Stormwater discharges in unincorporated Napa County are regulated through the Napa Countywide Stormwater Pollution Prevention Program, the State Construction General Permit, and Napa County Construction Site Runoff Control Requirements adopted by the Board of Supervisors on December 12, 2006. Permit Sonoma equivalents do not apply; Napa County Public Works Engineering Division administers locally.
Napa County is a permittee under the State Water Resources Control Board's Phase II MS4 Small Municipal Separate Storm Sewer System General Permit (Order 2013-0001-DWQ) and implements compliance through the Napa Countywide Stormwater Pollution Prevention Program (NCSPPP), a joint effort with the cities of American Canyon, Calistoga, Napa, St. Helena, Yountville, and the Napa County Flood Control and Water Conservation District. The Napa County Construction Site Runoff Control Requirements, adopted by the Board of Supervisors on December 12, 2006, require Best Management Practices for all earthmoving activity. Sites of one acre or more must obtain coverage under the State Construction General Permit (Order 2009-0009-DWQ as amended) and file a Storm Water Pollution Prevention Plan. Smaller projects must follow the NCSPPP Erosion and Sediment Control Plan (ESCP) Guidance Document. Illicit non-stormwater discharges to the MS4 are prohibited year-round.
Discharge of pollutants or sediment to the storm drain system, gutters, or waters of the state violates Clean Water Act Section 402 and the County's MS4 permit. State Water Board civil liability under California Water Code 13385 can reach $10,000 per day plus $10 per gallon. The county can require corrective Best Management Practices, withhold final inspection, and recover costs of cleanup. Violations of the Construction Site Runoff Control Requirements are enforceable as code violations.
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Napa County, CA
The Napa County Airport Land Use Commission (ALUC) administers the Airport Land Use Compatibility Plan (ALUCP), which uses a 65 dB CNEL noise contour around ...
Napa County, CA
Napa County has not adopted a county-wide 2 a.m.-6 a.m. overnight parking ban under California Vehicle Code Section 22507.5; the controlling rule is Napa Cou...
Napa County, CA
Napa County prohibits parking any vehicle on a county road for more than 120 consecutive hours under Napa County Code Section 10.08.150, and the California V...
Napa County, CA
Napa County has not adopted a stand-alone weight-based ordinance restricting commercial vehicle parking in residential districts; the controlling rules are C...
Napa County, CA
Driveways in unincorporated Napa County are regulated through Napa County Code Title 12 (Streets, Sidewalks, and Public Places) for encroachment permits at t...
Napa County, CA
Abandoned vehicles in unincorporated Napa County are addressed under California Vehicle Code Sections 22650-22711 (Removal of Parked and Abandoned Vehicles) ...
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