Williamson Creek Wastewater Interceptor

Austin Water is strengthening wastewater infrastructure and protecting Williamson Creek. Austin Water is currently in the final design and permitting phases for the Williamson Creek Wastewater Interceptor project. Construction is projected to begin in 2025 and anticipated to be fully constructed by 2030. Staff from the City of Austin's Capital Delivery Services Department and Austin Water are continuing to meet with neighbors in the project vicinity to discuss the project purpose and scope, as well as potential local impacts.

Project Scope

Installation of approximately 19,000 feet of a 72-inch diameter gravity interceptor pipeline along Williamson Creek from South First St. to Pleasant Valley Rd via tunneling construction method.
Replacement of multiple existing 8-inch to 36-inch local wastewater pipelines to divert and reconnect the wastewater flows to the new 72-inch diameter interceptor pipeline.
The new interceptor will remove as much of the existing 36-inch and 48-inch line from service as possible and also increase capacity in the sewer system to convey wastewater flows safely to the South Austin Regional Wastewater Treatment Plant.

Project Benefits

Greenbelt Expansion: Four acres of land will be conveyed to Parks & Recreation (PARD) stewardship, and an additional acre of trail easements will be purchased for PARD.
New Odor Control Facility: The facility will improve air quality and protect the interceptor from corrosion. It will be located along Onion Creek east of the intersection of S. Pleasant Valley Rd. and William Cannon Drive.
Expanded Community Access: Austin Water will build water quality ponds to service a trail parking lot that PARD plans to build in the future

Project Area

The project area is located in south and southeast Austin near Onion Creek and William Cannon Drive and continues northwest along Williamson Creek to the existing interceptor at South First Street.