The Los Angeles Regional Water Quality Control Board on July 23 adopted a regional permit for stormwater and urban runoff to control bacteria, trash and other pollution that flows from municipal storm drains into surface waters.
The permit sets limits on the amount of pollution discharged to the region’s waters to protect human health and the environment.
Under the previous MS4 permits first issued in the 1990s, Los Angeles County, Ventura County and the City of Long Beach were regulated by three separate board orders. This action consolidates the permits while reflecting the region’s diverse land uses and water quality characteristics by allowing customized approaches to meet requirements on a watershed basis.
Additionally, with its encouragement of stormwater capture and groundwater infiltration as an effective way to improve water quality, the permit increases local water supply resilience to climate change impacts.
The permit gives cities and counties the time and flexibility to choose, plan and construct stormwater projects that are appropriate for local conditions and generate other social, economic and water resource benefits such as creation of more parks and green spaces, clean streets, improved wildlife habitat and jobs.
“This is a very comprehensive, forward-thinking action to protect the health of our waters and our people,” said Lawrence Yee, chair of the Los Angeles Water Board. “The board worked hard to ensure equity for all communities and to require a level of transparency the public can understand.”
As one of the most heavily urbanized areas in the country, the rivers, lakes and beaches are significantly impacted by stormwater runoff that flows over land, collects pollutants and transports them to these water bodies via the region’s complex storm drain system. Urban runoff during dry periods from landscape irrigation, construction projects and car washing also carries pollutants through the storm drains to surface waters.
The board reached its decision following four days of hearings that included testimony from the cities and counties subject to the permit, environmental organizations and other interested stakeholders.
The National Pollutant Discharge Elimination System permit for the municipal separate storm sewer system (or “MS4”) covers discharges from 95 cities, Los Angeles County, Ventura County and their two respective flood control districts.