Wastewater System Improvements: Phase 3 & 4

Project Area
As part of the ongoing wastewater system improvements, the sewer system is being expanded on the Hill from Greenwood Street to the eastern edge of the City. The project includes the installation of gravity sewer mains, new force main piping, and connecting new users to the sewer system. The piping includes of 31,000 feet of gravity mains, over 15,000 feet of force main, and almost 41,000 feet of sewer service piping.
No wastewater treatment upgrades are planned; however, three new lift stations will be constructed through the eastern edge of the City. Other components of the project include upgrades to the existing Main Lift Station on Maiden Lane and extending sewer service to properties at and near the Rimrock Lodge.
The project was award to S&L Underground in August of 2025. S&L began construction on September 22, 2025, the completion date is estimated to be January 15, 2027 but will be updated as the project progresses. We do expect for winter shutdown on construction work for the winter of 2025/2026.
| Task | Month/Year |
|---|---|
| Bidding | Summer 2025 |
| Construction Begins | September 22, 2025 |
| Construction Completion | January 2027 |
- S&L underground is continuing to install sewer mainline throughout the community. They have completed the extension into the Solid Rock Estates Subdivision. The current focus of the project is to install sewer main around East Haley Ave., Golf St., Boulder St., and connecting streets in the area. The Contractor is currently finishing work at the new lift stations near the East Ramp and southwest of the High School.
- Please note that sewer service connections are currently planned to begin in late spring (May) or early summer (June). Please watch the City of Thompson Fall’s primary website for weekly road closures and expected working areas.
If there are any questions regarding this project, please reach out directly to City Hall at (406) 827-3557, tfl3557@blackfoot.net, or click here.