A city steeped in history—where the Lewis and Clark Expedition once camped—is forging a modern legacy in sustainability. Pasco, Washington, is advancing an ambitious plan to transform its wastewater infrastructure by converting process water from local food processors into renewable natural gas (RNG) and other environmentally beneficial byproducts.
The City of Pasco is collaborating with a consortium of industry leaders—Burnham RNG, Biogas Engineering, Cascade Natural Gas, Gross-Wen Technologies, Sustainable Energy Ventures, Swinerton Energy, and Xylem—to expand its Process Water Reuse Facility (PWRF) and the Pasco Resource Recovery Center (PRRC).
The PRRC processes wastewater from seven local food processing plants. Through innovative technologies and biological processes, the facility not only generates pipeline-quality RNG, but also produces soil amendments and algae for bioproducts. The system returns clean, treated water for agricultural irrigation, creating a circular, low-impact model for industrial water management.
“By repurposing water from food processing plants, we’re improving our environmental impact, meeting state and federal environmental standards, and harnessing valuable resources like renewable natural gas, all while sharing costs with industry partners,” said Maria Serra, Public Works Director for the City of Pasco.
The need for expanded wastewater treatment is growing alongside regional industrial development, including the construction of Darigold’s $600 million milk processing facility. As one of the newest system users, Darigold’s operations will further increase demand for advanced water treatment solutions.
The PWRF upgrade—part of a 30-year public-private partnership with Burnham RNG—will significantly boost treatment capacity and maximize environmental and economic benefits. “This project does much more than treat wastewater; it unlocks long-term value for the city of Pasco and its industries,” said Chris Tynan, CEO of Burnham RNG.
Once fully operational, the upgraded system will be capable of recycling more than one billion gallons of wastewater annually. The facility will treat water to a higher standard suitable for agricultural reuse. Two 34-million-gallon anaerobic digesters, supplied by Xylem, will break down organic material in the process water, producing raw biogas in the process.
Biogas Engineering will provide the gas upgrading technology to purify the biogas into high-quality RNG, which will be distributed locally by Cascade Natural Gas. Meanwhile, Gross-Wen Technologies’ algae-based greenhouse filtration system will recover nitrogen and sequester carbon dioxide, enhancing both water and air quality.
Treated water will be stored in expanded holding ponds until needed for irrigation, ensuring seasonal flexibility and resource optimization. Swinerton Energy served as the engineering, procurement, and construction (EPC) contractor for the PRRC.
Pasco, the seat of Franklin County in southern Washington, continues to make history—this time by setting new standards in industrial water reuse, sustainability, and renewable energy.