Stormwater Management

About the Program

The County's Clean Water Program is a function of the County government that exists to maintain compliance with a National Pollutant Discharge Elimination System (NPDES) Storm Water Discharge Permit and to promote storm water pollution prevention within that context. County compliance with the NPDES Permit is mandated by state and federal laws.
 

What Is Nonpoint Source Pollution?

"Nonpoint source pollution" is water pollution which occurs from many diverse areas of human activity within watersheds. These sources include illegal discharges, illegal dumping of solid or liquid waste, hazardous waste spills, chemical spills, agricultural operations, fertilizer application, soil sediment from construction projects, construction debris, improper grading, improper quarrying, sewage system and septic tank system discharges, vehicle and equipment washing, pesticide application, improper storage of solid waste, discharge of chemical substances, motor oil, antifreeze, paint, solvents, detergents, etc.

Nonpoint Source Pollution is transported by the storm water system or other surface water flows to local streams and bays. In contrast, a particular ongoing discharge from a wastewater plant or industrial facility is considered a "point source" of water pollution.

Nonpoint source pollution of streams and surface water is growing in importance as a national environmental issue. Unlike water pollutants that come from a single-point source (such as factories or wastewater treatment plants) nonpoint source pollutants originate from a variety of locations and are carried into storm drainage systems and creeks by storm water and other runoff. There are no treatment plants to manage nonpoint source pollution in our creeks, streams and bays. Prevention is the most effective way to reduce, minimize, and eliminate storm water pollution.

Where Does Nonpoint Source Pollution Go?

In northern Santa Clara County, nonpoint source pollutants flow into local creeks and streams, and eventually flow into south San Francisco Bay. Pollutants entering creeks and streams in the southern portion of the county ultimately flow to the Pajaro River and to Monterey Bay. Some of these pollutants, such as heavy metals and organic compounds, can concentrate to levels that are toxic to aquatic life, and contribute to significant environmental stress on streams and bays. These pollutants pose a serious problem for fish and wildlife dependent on Santa Clara County waterways, and for people who live and work near polluted streams or baylands. Nonpoint source pollutants may also infiltrate into the ground and contaminate the groundwater basin, which provides about half of the County's water supply. Pollutants can also contaminate the sediments that accumulate in flood control facilities, thus increasing maintenance and disposal costs.

A Brief History of Clean Water Program Government Regulation

In 1972 Congress adopted the federal Clean Water Act which requires pollutant discharges to navigable waters to be authorized by a National Pollutant Discharge Elimination System (NPDES) permit. Amendments to the act in 1987 include a section which required regulation of municipal and industrial storm water dischargers. It also required that individual control strategies (ICS) be developed by the storm water dischargers, to impose controls on nonpoint sources of pollution. This was in order to achieve compliance with water quality standards for "impaired" bodies of water. In 1989 the State Water Resources Control Board listed the south San Francisco Bay as impaired because water quality standards for heavy metals were frequently exceeded.

The Basin Plan issued by the Regional Water Quality Control Board (Regional Board) in 1986 and its subsequent amendments, would later require the Program to submit proposals for determining pollutant loading, sources and control measures for nonpoint source pollution to the south San Francisco Bay.

Recognizing that the proposed federal and state regulations would affect them all, north Santa Clara Valley's 13 cities, Santa Clara County and the Santa Clara Valley Water District - all jurisdictions which contribute runoff to the South Bay - joined forces to apply for a joint NPDES municipal storm water permit, rather than 15 separate ones.

In June of 1990 the Environmental Protection Agency (EPA) conditionally ruled that the NPDES permit satisfied the Clean Water Act's requirement for an ICS. The NPDES Permit was reissued in 1996 by the State Water Resources Control Board, on behalf of the US/EPA. The 2000 re-issuance of the NPDES Permit occurred in 2001 by the RWQCB.