The Sanitation Districts of Los Angeles County (Sanitation Districts) has awarded a $630m construction contract of the Clearwater Project to Dragados USA.
Sanitation Districts said that the project will protect local waterways by strengthening the aging infrastructure and will build a new 11.2km long, 18ft diameter tunnel to supply treated water from the Joint Water Pollution Control Plant in Carson to existing ocean outfalls at Royal Palms Beach in San Pedro.
Project construction will begin this year and is expected to be completed by the end of 2026.
Approval for the project was given in 2012, after evaluating the Sanitation Districts’ main sewer system, which serves over 5 million people in Los Angeles County.
Planning and environmental review effort included more than 500 public meetings to solicit input and the need for a new tunnel was identified.
Sanitation Districts stated that this new tunnel will be build using a modern tunnel boring machine. It is claimed that the technology has been used across the world and extensively in Los Angeles’ Metro system.
The Sanitation Districts the chief engineer and general manager Grace Robinson Hyde said: “As part of a thorough review of our system, we determined that the existing 60‐ and 80‐year old tunnels are insufficient for our future needs.
“These tunnels are critical because the majority of our treated water flow must pass through these tunnels. A new tunnel designed to current earthquake standards and sized to handle future peak storm flows will make our system more reliable.”
The Sanitation Districts is a regional agency that manages the wastewater needs of over 5.6 million people in 78 cities and unincorporated county areas.
Dragados is expected to bring its extensive tunneling expertise for the project. The company has completed over 530 underground projects in 20 countries, totaling more than 1,287km of tunnels.
Dragados vice president Tom Robertson said: “We look forward to working on this important infrastructure project. Our vast experience in tunneling through a wide range of geological conditions will be an asset for the Clearwater Project.”