Siebring Pump Station & Slurry Wall

Project Location: Greeley, Colorado

Project Description:

The Siebring soil-bentonite cutoff (also referred to as a slurry wall) wall and pump station was one of the first projects where a soil-bentonite cutoff wall was used to line a gravel mine along the Colorado Front Range. With this design-build project, Hall-Irwin Corporation utilized technology known and utilized in Florida. This technology in Florida was designed to keep ground water outside project limits; however, we utilized this same technology in reverse. This allowed existing gravel mines to be mined in the dry by keeping water out and served as future “buckets” for storing water after mining was complete.

At this project site, there were two different cells that were lined with the soil-bentonite cutoff wall to an average depth of 30 FT plus 3 FT into competent bedrock. Additionally, we built an interconnect between the two cells with a 5 CFS (cubic feet per second) pump station to convey water to the river and a diversion structure to allow water to be conveyed into the reservoir(s). After construction was completed, the overall capacity of this reservoir was 2200 AF (acre feet) of water storage.