City Commissioners approved final payment during their Sept.16 meeting to Sletten Construction for the water treatment plant solids mitigation project.

That’s $299,870.22 to Sletten and $3,028.99 to the state Miscellaneous Tax Fund.

Commissioners awarded the contract in January 2023 through the general contractor construction manager procurement method allowable under state law.

City Commission to consider $11 million water treatment plant project contract [2023]

The city contracted with Sletten and Advanced Engineering and Environmental Services, AE2S, for the project.

The Great Falls Water Treatment Plant “treats surface water from the Missouri River via conventional flocculation, sedimentation and filtration treatment processes. Residual solids, generally referred to as sludge, are generated from the primary/secondary clarification basins and clarification of filter backwash during the water treatment process,” according to the staff report.

In 2015-2016, the city retained AE2S to evaluate the existing WTP residuals management procedures and perform an alternative analysis that evaluated and recommended potential improvements.

City approves contract for lift station project [2023]

The evaluation recommended an overhaul of the existing storage pond system and construction of a screw press dewatering system, a new building to house the equipment, and site improvements to provide truck access to haul extracted solids off site, according to city staff.

The project has an estimated payback period of 25-30 years.

Commissioners voted in January 2023 to award the construction contract to Sletten with a maximum guaranteed price of $11,110,162, which is the final cost now that the project has been completed, according to staff.

When commissioners approved the contract, staff said completion was anticipated for March 2024.

City adjusting plan for Lift Station No. 1 project due to cost increases [2024]

The final checklist documents submitted to the city for completion are dated late August 2025.

In September 2021, the commission approved a professional services agreement to AE2S for design for the project.

AE2S recommended that the city’s project would be a good candidate for an alternative project delivery contract, as allowed under state law. The method allows for a more aggressive project completion schedule, early procurement of construction materials, managing project risk and negotiating project price, according to staff.

City Commission approves updated version of lift station repair contract

During their Jan. 4, 2022 meeting, commissioners approved a resolution to allow the use of the general contractor construction management method.

The city has since used the GCCM procurement method for other infrastructure projects, such as the Lift Station No. 1 improvement project.

The solids mitigation project was included in public works’ capital improvement plan and was funded through the water and sewer utility funds.