Walnut Creek WWTP Expansion To 100 Mgd and Enhancements Project (RFP)

Walnut Creek Wastewater Treatment Plant (WWTP) receives wastewater flow from Austin Water's wastewater collection system. The plant was originally built in 1977. Over the years, the treatment plant has undergone numerous improvements and upgrades to modernize treatment methods as well as expand treatment capacity to 75 million gallons per day (MGD) with a 2-hour peak flow of 165 MGD. Treated plant effluent is discharged into the Colorado River. A portion of the treated effluent is used for non-potable water (NPW) on the plant site and supplies much of the City’s Reclaimed Water program. This project will expand the plant to treat and discharge an annual average daily flow of 100 MGD and a 2-hour peak flow of 300 MGD. Th expansion is needed based on projected future flows of wastewater into the plant, in accordance with the Texas Commission on Environmental Quality (TCEQ) regulations and the requirements of Texas Administrative Code. Additionally, the project will implement Biological Nutrient Removal (BNR) in both the existing and proposed facilities to meet more stringent effluent quality limits in the plant’s discharge permit issued by TCEQ that will go into effect with the expansion. The project includes several distinct components: a new 25 MGD treatment train with BNR, upgrade of the existing treatment to BNR, new peak flow treatment, new influent siphons, new effluent pipe and outfall, and a flood wall around the site. See outside link.