Commissioners approve $2.78M contract for geopolymer lining of three large culverts

Douglas County commissioners on Sept. 9 approved a $2,778,770 construction contract with American West Construction LLC for a geopolymer spray-on lining project covering three large-diameter culverts (Project SP2025-019).

Deborah Kula, special projects engineer for county engineering, told the board the county has mapped about 30,000 storm-sewer segments, of which the county owns and maintains roughly 15,000 segments (described in the presentation as approximately 1,500,000 linear feet, or about 284 miles). Staff said inspections and prioritization continue and that the county’s normal storm-sewer maintenance budget of about $4.5–$5 million per year supports a limited number of replacements and lining projects.

Kula said research with suppliers and partners, including information verified via CDOT resources, showed geopolymer spray-on lining would allow the county to complete the three large culvert repairs for approximately the cost of slip-lining a single location. The three locations presented were: Rampart Range Road at Village Circle (near Roxborough Elementary School), a dual 126-inch culvert under Broadway adjacent to North Bridle Recreation Center, and a 90-inch culvert under University (running from Wildcat Reserve Parkway to an outfall near Fallbrook Drive/East Ridge Rec Center). Staff recommended approval of the contract and said the approach extends the number of large culverts that can be maintained within existing budgets.

Commissioners voted to approve the award by voice vote; the motion passed unanimously with one commissioner excused. After the contract approval the board returned to and approved its consent agenda (items a–z) by motion and voice vote.

Ending: Engineering staff will proceed with contract execution, scheduling and traffic/neighbor notifications as required by the project plan.