Draft Permit Could Require Changes at Sacramento Regional Wastewater Treatment Plant
The Central Valley Regional Water Quality Control Board has released a draft discharge permit that could require the Sacramento metropolitan area to reduce the amount of ammonia it discharges into the Sacramento River from its wastewater treatment plant.
The Sacramento Regional County Sanitation District is seeking renewal of its permit to discharge secondary-level treated wastewater from its regional treatment plant near Freeport. The treatment plant, which utilizes several sedimentation processes, chlorination, dechlorination, and the dilution power of the river, does not remove ammonia from the wastewater stream.
Recent studies have suggested that ammonia and other nutrients may be disrupting the food web in the environmentally troubled Delta, contributing to the decline in native fish populations such as Delta smelt.
Effluent from the treatment plant has been identified as the largest single source of ammonia in the Delta watershed. The Sacramento Regional County Sanitation District has said upgrading the treatment plant to remove ammonia would cost approximately $800 million. The district has also said there is not enough scientific evidence to justify requiring the district to remove ammonia.
The draft discharge permit could also require the district to remove pathogens through tertiary filtration and disinfection, which the district estimates would cost an additional $1.3 billion. The draft permit proposes a 10-year timeframe for the district to comply with the new requirements.
Laura King Moon, assistant general manager of the State Water Contractors, said all factors affecting the Delta’s health must be addressed, including significant sources of ammonia.
“As public water agencies, we’ve been working to find a balanced solution to this crisis, and we believe that this is an element that needs to be addressed. Sanitation districts throughout California have taken the necessary steps to upgrade their systems, Sacramento should do the same,” she said. “We’re pleased to see that the California Regional Water Quality Control Board has found – based on solid research and science – that the amount of ammonia flowing into the Delta must be significantly reduced.”
ACWA Executive Director Timothy Quinn applauded the regional board for attempting to address a complex issue.
“The board’s action is illustrative of the need to pursue the co-equal goals of water supply reliability and ecosystem health in a broad, comprehensive manner that aggressively addresses all environmental stressors,” Quinn said. “We would urge the regional board to effectively solve the underlying ecological problems expeditiously, but also with the flexibility to help keep costs down for Sacramento Regional and its ratepayers.”
The regional board is tentatively set to consider approval of the permit in December. It will accept comments on the draft permit through Oct. 8. Details can be found on the board's website.
