San Jose study session outlines multibillion-dollar overhaul at Regional Wastewater Facility and new nitrogen limits

San Jose officials on Jan. 31 received a briefing on the San Jose–Santa Clara Regional Wastewater Facility’s decade‑long capital improvement program, the facility’s operational capacity and recent regulatory changes that staff say will require additional treatment investment over the next decade.

The study session, led by Laurie Mitchell, acting director of the Environmental Services Department, and a team that included the RWF general manager, deputy directors for capital programs and regulatory affairs, and the city’s real‑estate lead, reviewed completed projects, ongoing work, anticipated costs and new nutrient discharge limits adopted by Bay regulators in July 2024.

The update matters because the RWF treats sewage for San Jose, Santa Clara and multiple tributary districts, discharging treated effluent to the Lower South San Francisco Bay; regulators have imposed regionwide reductions in nitrogen loads after large algal blooms in 2022 and 2023 prompted concern about fish kills and toxins. Those limits will drive additional capital projects and financing decisions affecting ratepayers and regional planning.

Staff said the city has delivered a large portion of the plant master plan adopted in 2013 and highlighted several major completed projects, including a new headworks facility and a cogeneration plant. "The capital improvement program is a multi billion, multi decade long program intended to renovate and modernize the regional wastewater facility," Mariana, the plant general manager, told the council. The cogeneration project, completed using progressive design‑build, was described in the presentation as an award‑winning, $115,000,000 project that produces roughly 80% of the plant’s energy needs and provides resilience during external power losses.

City staff described program delivery changes since adoption of the…