Last month, one of the county’s most significant yet little-known infrastructure projects received a major boost.
On May 11, the U.S. Environmental Protection Agency announced a $441 million Water Infrastructure Finance and Innovation Act loan to the Los Angeles County Sanitation Districts to support the roughly $700 million Joint Water Pollution Control Plant Effluent Outfall Tunnel Project, also known as the “Clearwater Project.” The loan will lower interest payments for the project.
This tunnel project will combine two aging treated wastewater tunnels into one bigger replacement tunnel that meets current seismic safety standards and is less likely to result in unplanned sewage releases.
The existing tunnels carry water from the Los Angeles County Sanitation Districts’ largest wastewater treatment plant in Carson roughly seven miles to treated sewage outfalls off the coast of the Palos Verdes Peninsula. The system serves roughly 5 million people in 78 cities and unincorporated communities along a huge swath of the county from the foothills of the San Gabriel Mountains stretching southwest to Long Beach and the Palos Verdes Peninsula.
These tunnels were built in 1937 and 1958 and do not meet the latest seismic standards, a critical problem given that they cross the active Newport-Inglewood Fault Zone. In addition, with their diameters of eight and 12 feet, the tunnels’ capacities were nearly breached twice – most recently in January 2017. Major releases of partially treated or untreated wastewater were narrowly avoided.
The 7-mile-long replacement tunnel now under construction will have a diameter of 18 feet and is designed to current seismic standards. It’s expected to have sufficient capacity for the high-water flows experienced during major storms.
“Unfortunately, the tunnels that our community’s main sewer system relies on to prevent wastewater from flooding our waterways are nearly a century old and at risk of failure during severe storms and earthquakes,” U.S. Rep. Linda Sanchez, D-Norwalk, said in the EPA loan announcement. “This funding will be used to replace our aging infrastructure, preventing contamination of our drinking water while creating good-paying jobs right here in our region.”
The project began in 2019 and is expected to be completed in 2027. Last summer, the most crucial phase of the project began when a tunnel-boring machine was lowered into place.
The EPA loan, which is coming from a fund created through the 2014 Water Infrastructure Finance and Innovation Act, will allow the Sanitation Districts to save roughly $76 million in financing costs, which in turn will lower the surcharges imposed on ratepayers for the project. Those surcharges range between $5 and $7 per year for the owners of single-family homes.