Caldwell Wastewater Treatment Plant Improvements

Project Summary

IMCO upgraded the industrial wastewater treatment plant at Darigold’s Caldwell butter plant. These improvements allow their discharged waste to remain compliant with environmental requirements.

IMCO crews demolished an existing storage building and constructed a new dissolved air flotation (DAF) treatment building, a second glass lined steel equalization tank, and pre-engineered metal building.

The DAF unit provides chemical and physical treatment of the industrial waste. Conventionally treatable waste is discharged into the sewer system while solids are removed and pumped into trucks that dispose of the solids generated by the development of Darigold’s adjacent butter facility.



Caldwell, Idaho



Contract Amount

Confidential at Owner's Request (< $5 Million)


August 2021 – June 2022

Project Highlights

The equalization tank was constructed from the top to bottom. Crews worked their way down using hydraulic jacks to lift the previously built ring above them, while installing the next ring in line. This activity required strategic planning and coordination by the crew to safely and successfully complete.