Vacaville, CA Environmental Rules: Stormwater Management (2026)

Vacaville Municipal Code Chapter 14.26, with Section 14.26.020 (Discharge Prohibitions) as the operative provision, makes it unlawful for any person to discharge, or cause to be discharged, into the municipal storm drain system or watercourses any materials - including pollutants or waters containing pollutants - that cause or contribute to a violation of applicable water-quality standards, other than uncontaminated storm water. Illicit connections to the storm drain are also prohibited; the chapter explicitly addresses both physical illicit connections and operational illicit discharges. Common prohibited discharges include vehicle washwater, pressure-wash effluent, paint, concrete slurry, soapy water, oil, sediment from grading sites, and chlorinated pool water. Permitted exceptions include firefighting flows and discharges authorized by NPDES permit or waste discharge order. Construction projects disturbing one or more acres of soil must enroll in the California State Water Resources Control Board's Construction General Permit (Order 2022-0057-DWQ) and prepare a Storm Water Pollution Prevention Plan (SWPPP). Vacaville is a co-permittee under the Phase II MS4 General Permit (Order 2013-0001-DWQ as amended). The city's storm drains discharge to Alamo Creek, Ulatis Creek, Putah Creek tributaries, and ultimately the Sacramento-San Joaquin Delta. Report illicit discharges to Vacaville Utilities or the Public Works Director.