Stormwater home page City of Los Angeles home page
      Department of Public Works Bureau of Sanitation

What is the state of Santa Monica Bay?

Santa Monica Bay is a tremendous resource for Southern California. Its world-renowned beaches and rich marine waters beckon millions of us to its shores year after year. Socially and economically, we depend upon a healthy Bay.

Yet, since the 1800’s our community has discharged pollutants into the Bay and we have allowed this natural resource to absorb our wastes. The Santa Monica Bay has responded by diminishing the diversity and vitality of its marine life. When the overall health of our environment diminishes, the long-term character of our entire region becomes threatened.

The City of Los Angeles has embarked upon an unprecedented program of sewage treatment improvements, and has begun to reverse the trend of Bay pollution. The return to natural, balanced marine conditions is underway, yet much remains to be completed to reduce the rate of pollutant discharge.

It is time to finish the job.

What will it take to clean up Santa Monica Bay?

The Bay will clean itself naturally as the flow of pollutants is reduced. Construction of new treatment systems at the Hyperion Plant is the most significant project in the City ‘s program to reduce pollution. These new systems will remove over 95% of the solids from 450 million gallons of wastewater each day.

Discharges from other agencies, cities, and private companies, and stormwater drains must also be properly treated. Cleaning up wastes to protect Santa Monica Bay must be a regional effort.

Where does sewage come from?

Each one of us produces 100 to 120 gallons of wastewater per day. The vast majority of this flow originates in homes: from sinks, toilets, showers, laundries, dishwashers, and garbage disposals. Nearly four million people and over 100, 000 businesses and industries in Los Angeles use the sewer system.

Several cities and agencies contract with Los Angeles for sewer service. These include West Hollywood, Beverly Hills, Santa Monica, San Fernando, Culver City, El Segundo, Burbank, Glendale, and Los Angeles County.

How is sewage treated today?

Incoming sewage is screened in the headworks of each treatment plant to remove grit and large objects.

At the City of Los Angeles’ Hyperion Treatment Plant, most of the solids in wastewater settle out in primary tanks. Nearly two-thirds of the daily flow is then pumped into Santa Monica Bay. The remaining one-third is treated further, using biological processes to further purify prior to ocean discharge. This is referred to as secondary treatment.

Wastewater treated at the Los Angeles – Glendale and Donald C. Tillman Water Reclamation Plants is filtered after secondary treatment to produce reclaimable water. The Terminal Island Treatment Plant treats all wastewater with primary and secondary processes.