Williamson Creek Wastewater Interceptor
Austin Water is strengthening wastewater infrastructure and protecting Williamson Creek with the Williamson Creek Wastewater Interceptor project.
The project will install approximately 19,000 feet of 72-inch diameter gravity interceptor pipeline along Williamson Creek from South First Street to Pleasant Valley Road using tunneling construction. It will also replace multiple existing 8-inch to 36-inch local wastewater pipelines to divert and reconnect flows to the new interceptor, removing as much of the existing 36-inch and 48-inch line from service as possible and increasing system capacity to safely convey wastewater to the South Austin Regional Wastewater Treatment Plant.
The project area runs through 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.
Project Benefits
Greenbelt expansion — Four acres of land will be conveyed to Austin Parks and Recreation stewardship, with an additional acre of trail easements purchased for future park use.
New odor control facility — A new facility along Onion Creek east of the intersection of South Pleasant Valley Road and William Cannon Drive will improve air quality and protect the interceptor from corrosion.
Expanded community access — Austin Water will build water quality ponds to serve a trail parking lot that Austin Parks and Recreation plans to construct in the future.
Timeline
| Phase | Dates |
|---|---|
| Design and permitting | Fall 2017–Spring 2025 |
| Advertisement | Spring 2025–2026 |
| Construction | 2026–2030 |
Communications
Past Meetings
- June 20 and 25, 2024 — Presentation boards (PDF), Meeting invitation (PDF), Invitación en español (PDF)
- Nov. 13 and 15, 2017 — Meeting presentation (PDF)
Documents
- Project map (PDF)
- Project fact sheet (PDF)
- July 24, 2024 tunneling projects contractor open house — video recording (YouTube)
- Contractor open house attendance (PDF)
- Contractor open house questions (PDF)
- Williamson Creek wastewater improvements — drone footage playlist (YouTube)
- Williamson Creek wastewater improvements 2024 — drone footage playlist (YouTube)
Contacts
Craig McColloch, Project Manager
Austin Capital Delivery Services
512-749-3412
craig.mccolloch@austintexas.gov
Cynthia Miller, Public Information
Austin Water
512-972-0268
cynthia.miller@austintexas.gov