In 1972, the Clean Water Act (CWA) was amended to provide that the discharge of pollutants to waters of the United States from any point source is effectively prohibited, unless the discharge is in compliance with a NPDES permit. The 1987 amendments to the CWA added Section 402(p), which establishes a framework for regulating municipal and industrial stormwater discharges under the NPDES program.
Federal law requires that industrial stormwater discharges meet all provisions of Section 301 and 402 of the CWA in order to control pollutant discharges. These provisions require the use of best available technology (BAT) economically available and best conventional pollution control technology (BCT) to reduce pollutants and any more stringent controls necessary to meet water quality standards.
In California, the State Water Resources Control Board (SWRCB), through the nine Regional Water Quality Control Boards (RWQCB), administers the NPDES stormwater permitting program. For industrial facilities and construction activities, the SWRCB elected to issue statewide general permits that apply to all stormwater discharges requiring an NPDES permit. A copy of the General Permit for industrial facilities may be obtained from the SWRCB's website.
In addition to the stormwater industrial General Permit, the RWQCB may, at their discretion, issue an industry-specific General Permit. For this reason, the readers are advised to contact their local RWQCB (San Francisco Bay, Central Valley). Industries may also request an individual NPDES permit instead of the general permit. The process, however, is expensive and time consuming and the RWQCB may eventually choose not to issue an individual permit. RWQCBs are only expected to consider individual permits where an individual facility has unique characteristics or poses a significant threat to water quality. The General Permit generally requires facility operators to:
The Stormwater Best Management Practice Industrial and Commercial Handbook has many examples of BMPs that may be used to prevent pollution and also includes guidance on how to prepare a SWPPP.