Regulatory Information

The Clean Water Act prohibits the discharge of pollutants into a water body without an NPDES permit.

Industrial & Manufacturing Regulations

The Industrial General Permit is an NPDES permit that regulates discharges associated with nine broad categories of industrial activities, including manufacturing plants, mining operations, disposal sites, recycling centers and transportation facilities. The permit requires the development of a Stormwater Pollution Prevention Plan that identifies sources of pollution and describes the measures the facility has taken to reduce stormwater pollution.


The General Construction Activities Stormwater Permit may be required for any business that engages in construction or demolition, including clearing, grading, grubbing or excavation. Any activities that result in a disturbance of land of one acre or more may also need to apply and adhere to the General Construction permit.

Rules and Regulations

Created in 1972 by the Clean Water Act, the NPDES permit program addresses water pollution by regulating point sources that discharge pollutants into US waterways. Point sources are natural or manmade conveyances like pipes or ditches.

The regional board that oversees your jurisdiction determines your specific NPDES permit. Riverside County Watershed Protection includes three different water quality control boards that govern the Santa Ana, Santa Margarita and Whitewater watersheds. These boards are responsible for managing the County’s MS4 NPDES permit and ensuring compliance.

Access NPDES permits, compliance documents, monitoring plans and all other regulatory documents from the Riverside County Flood Control and Water Conservation District.

Not sure which watershed you’re in? Use our map to find out.

Riverside County Watershed Protection