Clean Water SoCal and CASA Celebrate Major California Clean Water Achievement

Clean Water SoCal and the California Association of Sanitation Agencies celebrate the state's outstanding clean water performance on May 13th at the City of Corona's training facility.

According to California's Integrated Water Quality System (CIWQS), the total number of sewer spills is now at the lowest level since the state began recording data in 2007.

A remarkable example: Central Valley (Region 5) wastewater agencies and cities have reduced the number of spills from 2,607 incidents in 2008 to just 189 last year.

Well maintained and functioning wastewater infrastructure = swimmable, fishable, and drinkable water for all Californians.

Last week, members of Clean Water SoCal and the California Association of Sanitation Agencies celebrated this major clean water milestone during a joint meeting in the City of Corona.

It's a remarkable achievement that took 20 years of hard work, investment, and collaboration between wastewater agencies, regulators, vendors, wastewater professionals, and their associations.

Here's to California's wastewater professionals - we are flush with success! The celebratory cake was very tasty as well.

Details are available at CaliforniaSewerSpills.com, a data analysis website developed by Lars Stenstedt.

 Significant Dates in California's Sewer System History

1860 - San Francisco built their first brick-lined sewers.

1870 - Santa Barbara builds their first sewers

1880 - Fresno designs their first sewer lines leading to a 40-acre sewer farm.

1887 - San Diego built a 40-mile network of vitrified clay pipe sewer lines designed by famed sanitary engineer Col. George E. Waring. The wastewater dumped directly into San Diego, a problem that would need to be solved decades later.

1887 - Fred Eaton, famous for the Los Angeles Aqueduct, designs and leads installation of the City of LA's first sewer system. 

1899 - The Ross Valley Sanitary District is formed in Marin County, one of the oldest sewer districts in the state.

1908 - the City of Los Angeles builds the Central Outfall Sewer (COS), a bricked lined pipeline from downtown LA to Play del Ray, and still in use today. It has been rehabilitated several times, including a major overhaul in the early 2000s.

1910 - Sacramento builds their first sewers in the downtown core.

1936 - Reuben Brown’s Fantastic Voyage in LA’s North Outfall Sewer Line

1949 - The State and Regional Water Pollution Control Boards are formed by the Dickey Act.

1967 - State Water Resources Control Board is created, merging the water rights and water quality control boards.

1969 - California's Porter-Cologne Act Water Quality Act is passed.

1972 - Federal Clean Water Act is passed.

1976 - CWEA's Collection System Maintenance certification was created.

2006 - State Water Board General Order for Sanitary Sewer Systems Waste Discharge Requirements

2007 - Agencies upload their Sanitary Sewer System Management Plants (SSMPs) and any spill reports to the  California Integrated Water Quality System (CIWQS)

2022 - Revision to the State Water Board General Order for Sanitary Sewer Systems Waste Discharge Requirements

2025 - The total number of sewer spills per year is at the lowest level ever since the state started recording spill data in 2007.