The Stormwater Program in the
Los Angeles Region


Stormwater is defined by US EPA as the runoff generated when precipitation from rain and snowmelt events flows over land or impervious surfaces without percolating into the ground. As it flows, stormwater runoff collects and transports pollutants to surface waters. Some of these pollutants are visible such as sediment, motor oil and trash, as well as pollutants that are not easily visible such as dissolved metals, nutrients, oxygen demanding substances, and organic chemicals.

Although the amount of pollutants from a single residential, commercial, industrial or construction site may seem unimportant, the combined concentrations of contaminants threaten our lakes, rivers, wetlands and other water bodies. Pollution conveyed by stormwater degrades the quality of drinking water, damages fisheries and habitat of plants and animals that depend on clean water for survival. Pollutants carried by stormwater can also affect recreational uses of water bodies by making them unsafe for wading, swimming, boating and fishing. In most cases, stormwater flows directly to water bodies through separate storm sewer systems, contributing a major source of pollution to rivers, lakes, and the ocean.

Stormwater discharges in California are regulated through National Pollutant Discharge Elimination System (NPDES) permits. However, stormwater may also act as a resource and recharge groundwater when properly managed. The Water Boards are actively involved in initiatives to improve the management of stormwater as a resource.

In the Los Angeles region, the stormwater program is a comprehensive program to manage the quality of discharges from the municipal separate storm sewer system in the incorporated and unincorporated areas in Los Angeles, and Ventura counties, the discharges from the 10 categories of industries listed in the Federal Regulations (40 CFR 122.26), and the discharges from construction sites with land disturbance of 1 acre or more.

Construction
General Permit
Industrial General
Permit
Municipal
Permits
Caltrans
Permit
CII
Permit

  • Nutrients such as phosphorus and nitrogen can promote the overgrowth of algae, deplete oxygen in the waterway and be harmful to other aquatic life.
  • Bacteria from animal wastes and illicit connections to storm sewer systems can make nearby lakes and bays unsafe for wading, swimming and the propagation of edible shellfish.
  • Oil and grease from automobiles causes sheen and odor and makes transfer of oxygen difficult for aquatic organisms.
  • Sediment from construction activities clouds waterways and interferes with the habitat of living things that depend upon those waters.
  • Careless application of pesticides, herbicides and fertilizers affect the health of living organisms and cause ecosystem imbalances.
  • Litter damages aquatic life, introduces chemical pollution, and diminishes the beauty of our waterways.
  • Heavy metals and organic chemicals from industrial facilities can cause toxicity in the aquatic life that use our waterways.
The best way to control contamination to stormwater is usually at the source, where the contaminants can be identified, reduced or contained before being conveyed to surface water. More often than not, it's more expensive and difficult to remove the combination of contaminants that are present at the end-of-pipe where stormwater is finally discharged directly to a receiving waterbody. Employing best management practices, or "BMPs" to prevent contamination of stormwater is key. Proper storage of chemicals, good housekeeping and just plain paying attention to what's happening during runoff events can lead to relatively inexpensive ways of preventing pollutants from getting into the runoff in the first place and then our waterways.
If you are required to obtain coverage under either the Industrial General Permit or the Construction General Permit and you have not obtained coverage, do so right away. Please visit the Industrial Stormwater Program page or the Construction Stormwater Program page for information on how to apply for coverage. Municipalities with questions about compliance, please visit the Municipal Stormwater Program page for information. If you already have coverage under either the Industrial General Permit or the Construction General Permit, it is your obligation to comply with the requirements in these permits. Please see the Industrial and Construction Stormwater Program pages for the details on the requirements. You can also report a facility or a construction site that does not have stormwater permit coverage. These non-filers have an undue financial advantage over the industrial facilities and construction sites that comply with the regulations.

Senate Bill 205 (2019) was signed by Governor Gavin Newsom on October 2, 2019 and became effective January 1, 2020. This Senate Bill added sections 16000.3 and 16100.3 to the Business and Professions Code and section 13383.10 to the Water Code, and requires a person applying to a city or county for a new or renewed business license to demonstrate enrollment in a National Pollutant Discharge Elimination System (NPDES) stormwater permit, if such a permit is required. Prior to the issuance or renewal of a business license, the city or county determines whether any of the primary Standard Industrial Classification (SIC) codes provided by the business are potentially regulated by the NPDES General Permit for Stormwater Discharges Associated with Industrial Activities (Industrial General Permit).

The Los Angeles Regional Board Stormwater Compliance and Enforcement Unit staff hosted SB 205 Workshops for the counties and municipalities in the Los Angeles Region. See workshop recording below.

Senate Bill 891 (2022) expanded the application of the current (SB 205) law provisions to ‘instruments or permits’ equivalent to business licenses and to the renewals of those equivalent ‘instruments or permits’.

Helpful Websites:

Workshops

Other Tools

Recent News:

STORMWATER PROGRAM CONTACTS: