AECOM, a leading infrastructure consulting firm, has been appointed by the City of Austin as the prime consultant for the expansion of the Walnut Creek Wastewater Treatment Plant (WWTP) in Texas. This project aims to modernize the aging facility and increase its capacity from 75 million gallons per day (MGD) to 100 MGD, addressing Austin’s growing population and bolstering the city’s wastewater infrastructure.
Originally built in 1977 with an initial capacity of 18 MGD, the Walnut Creek WWTP has seen several expansions to reach its current 75 MGD. AECOM’s involvement will ensure that the plant can meet future demand while improving operational efficiency and environmental sustainability. The upgrades will include replacing outdated equipment, adding a new 25 MGD treatment train, and constructing a 120-inch outfall line. The plant will also feature advanced wet weather treatment systems, including 100 MGD cloth filters, and a flood wall to safeguard against 100-year flood events, based on updated flood risk data from the National Weather Service’s Atlas 14 study.
AECOM’s scope encompasses process, mechanical, civil, electrical, and structural engineering services. By leveraging its global expertise, the firm aims to enhance water quality, protect the local ecosystem, and maintain the plant’s operations throughout the upgrade.
The Austin City Council recently approved over $1 billion for the project, which includes $270 million for renewing essential components, $440 million for expanding capacity by 25 MGD, $220 million for upgrading to nutrient removal and UV disinfection, and $120 million for wet weather facilities and flood protection infrastructure.