OUR BLOG: INSIDE THE LIFT

23Feb 2014

Lift Station Slab Stabilization

By uretekhr

When two separate attempts to seal water infiltration into a lift station failed using other technologies, the Toho Water Authority called on URETEK Holdings to utilize its Deep Injection technology as a final solution.

The work site at the lift station.
The work site at the lift station.

Prior to installation of the injection tubes, the Toho staff and the crew at Ground Penetrating Radar Services (GPRS), assisted in identifying the location of buried service connections so they wouldn’t be impacted during the repair.  The URETEK Team then hydro-lanced through the first ten feet of soil using this “soft” driving technique to avoid damage to underground utilities within the injection zone.

The repair commenced with installation of injection tubes using surgical precision to apply URETEK’s 486STAR polymer directly to the problem zones, which were located at the pre-cast structure’s horizontal joints.

Injection points around the circular slab and discharge pipes
Injection points around the circular slab and discharge pipes

Injection points were spaced at pre-determined intervals and elevations to coincide with the lift station’s failed seals.  A total of eighteen locations were equally spaced around the circumference of the lift stations with the 486STAR polymer injected at three discrete elevations.  The injection process was closely monitored to prevent unintentional lift at the surface or damage to the buried service connections.

Working in close quarters.
Working in close quarters.

Steven Gibbs, URETEK’s project manager on the job, reported that the team successfully completed the project in one work shift, without impact to the buried service connections, all while working in tight quarters and keeping the lift station in continuous service.