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.
Napa County, CA
Unincorporated Napa County does not have a stand-alone leaf-blower ban. Powered garden tools (leaf blowers, mowers, chainsaws) are regulated under the genera...
Napa County, CA
Napa County Code §8.16.080 prohibits operating any loudspeaker or amplified-sound device when the sound creates a noise disturbance or violates the exterior ...
Napa County, CA
Napa County Code §8.16.080 prohibits keeping or maintaining any animal that causes annoyance or discomfort to two or more reasonable persons of normal sensit...
Napa County, CA
Napa County Code §8.16.080 prohibits the operation of construction or demolition tools or equipment between 7:00 p.m. and 7:00 a.m. when the sound creates a ...
Napa County, CA
Unincorporated Napa County regulates noise under County Code Chapter 8.16 (Noise Control Regulations). Sections 8.16.060 and 8.16.070 set interior and exteri...
Napa County, CA
Commercial vehicle parking in unincorporated Napa County is regulated through Napa County Code Title 10 (Vehicles and Traffic), Title 18 (Zoning), and Califo...
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