San Antonio Water System (SAWS) and private company Ameresco Inc., have opened a biogas facility at the Dos Rios Water Recycling Center — the first sustainable project of its kind in the nation, capturing biogas generated during the sewage treatment process and selling it through a commercial gas pipeline.
Methane gas is generated by biosolids during the sewage treatment process. Previously, SAWS burned off the gas using flares. With this 20-year partnership, Ameresco will treat and transfer at least 900,000 cubic feet of gas to a nearby commercial gas pipeline, where it will be sold on the open market. In return, SAWS ratepayers will receive a royalty on the sale of the gas, estimated at $200,000/ year, reducing the cost of SAWS operations and keeping rates affordable.
With the addition of the biogas facility, SAWS is recycling and reusing almost all of the waste coming into Dos Rios through its “recycling trifecta,” which also includes the reuse of bio-solids to generate compost and water recycling. About 115 million gallons a day of high-quality recycled water are used for the Riverwalk, golf courses, parks, and commercial and industrial customers as well as in the upper San Antonio River and Salado Creek.