By: Jorge Lopez, P.E., Vice President, Engineering

The California Public Utilities Commission (CPUC) authorized Suburban to construct the PFAS removal plant at Plant 201 in December 2024. It will be the largest individual project, most expensive and most complex in Suburban’s long history. PFAS is a group of synthetic chemicals resistant to heat, water, and oils. It is known as a forever chemical because it doesn’t break down easily in the environment.

The CPUC authorized Suburban’s request of $21 million in 2025 to build the project. We estimate the total cost of the treatment plant will be more than $40 million and take more than two years to complete. The project must be completed before the Environmental Protection Agency (EPA) starts enforcement of the Maximum Contaminant Levels (MCL) for Per-and polyfluoroalkyl substances (PFAS) in 2029.

The treatment plant will remove PFAS from the groundwater produced by wells at Plant 201 that serve the Whittier-La Mirada (WLM) customers. The treatment plant’s capacity is 15 Million Gallons Per Day (MGD) and will serve as the primary source for the WLM system. 

Suburban’s Engineering Department engaged consulting engineers Carollo Engineering to design the treatment plant starting in 2020 in anticipation of EPAs MCL. Carollo is a leading global engineering firm that has extensive experience working on similar projects. The treatment plant’s design has been completed, and Ion Exchange (IX) technology was selected because it has the lowest life cycle cost for our application compared to other technology. The treatment plant will have seven sand separators, three cartridge filters, 16 media vessels (17 feet high and 12 feet in diameter), and a sophisticated Supervisory Control and Data Acquisition (SCADA) system to operate and monitor the treatment plant. 

Engineering is working with the City of Pico Rivera to obtain all necessary permits to start project construction as early as the second quarter of 2025. The first sequence of the project involves building an earthen mound to raise the treatment plant above flooding levels behind the Whittier Narrows Dam, and new piping to collect water from the wells and deliver it to the treatment plant.

We will update you on this critical project during major milestones until the treatment plant is operational. The Plant 201 Treatment Plant demonstrates Suburban’s constant commitment to ensuring a safe and reliable water supply to our community of over 120,000 people who rely on this water.