Completed in 2020, Oro Loma’s Nutrient Optimization Project (NOP) has received an Award of Excellence  for Outstanding Capital Project from the California Association of Sanitation Agencies (CASA).  This award recognizes exemplary wastewater capital projects.  The projects were judged on their unique or innovative design and construction applications, engineering applications, technical advancements, and/or difficult challenges of the project.

NOP LOGOInnovative Nutrient Optimization Project Reduces Nitrogen Levels in the San Francisco Bay and Protects the Environment 

Started in 2018, completed in August 2020, and operational since then, the Nutrient Optimization Project was a major upgrade to the District’s treatment plant. The project converts the wastewater treatment process from how it has been running for decades to a new process that removes half the nitrogen loading from the influent. This project was one of the first to provide both nitrification and denitrification processes within the San Francisco Bay area. This effectively reduces the nitrogen loading to the Bay by converting ammonia into nitrogen gas. The reduction of nitrogen to the Bay can reduce the potential for algal blooms, which can lead to fish kills.

The goal was to remove half of the nitrogen from the influent flow. Through this proactive effort to get ahead of any nutrient limits, Oro Loma was able to improve the water quality and obtain an additional discharge permit to reinstate its local outfall for wet weather discharges.

The first of its kind in the Bay Area, the Nutrient Optimization Project was completed on time and under budget. The new discharge permit requires an annual ammonia removal rate of 70%. The new biological nutrient removal of the treatment plant expansion far exceeds the removal rate. The treatment plant is removing closer to 95% of the ammonia from the influent flow.

NOP wastewater plant