What is the Clearwater Project?

The Sanitation Districts operate and maintain the Joint Outfall System (JOS), the main sewer system that collects and treats the wastewater (sewage) from over 5 million people in the Los Angeles basin. The largest wastewater treatment facility in the JOS, the Joint Water Pollution Control Plant (JWPCP) in Carson, uses two large tunnels to convey water to the ocean. The tunnels are 60 and 80 years old.

In 2012, the Sanitation Districts’ Board of Directors approved the Clearwater Project Master Facilities Plan, which will protect local waterways by addressing aging infrastructure. A major component of this project is a new 7-mile long tunnel that will be constructed almost entirely underneath public right-of-way (streets). The figure below shows the alignment of the new and existing tunnels.