Sacramento to expand wastewater treatment plant

California water authorities will invest between $1.5bn and $2bn to expand and upgrade the Sacramento Regional Wastewater Treatment Plant located near Elk Grove.

The plant has been releasing numerous pollutants into the Sacramento river, harming public health and aquatic life in the Sacramento-San Joaquin Delta.

The Central Valley Regional Water Quality Control Board found high volumes of ammonia in the water which the district plans to break down using bacteria in open-air tanks.

The board has also ordered a clean-up of the plant’s effluent by adding additional layers of filtering and disinfection to reduce pollutants that disrupt the food chain and endanger fish such as salmon and Delta smelt.

Sacramento Regional County Sanitation District engineer and treatment plant head Prabhakar Somavarapu told sacbee.com: "When we upgrade the plant in seven or eight years, our entire output is available for recycling."

The plant, built in the late 1970s, already has a small, outdated unit in place that has the capability to produce about three million gallons of recycled water daily.