Koehler has led some of Barnard’s largest heavy civil projects in the last decade. His expertise includes the construction of large-scale dams, including roller-compacted concrete and zoned earthen dams. His work on the Boone Dam Internal Erosion Remediation Project earned the 2022 CURT Construction Industry Project Excellence Award and his work on the Muskrat Falls North and South Dams earned the 2019 ENR Global Best Project Award in the Dam/Environment category. Currently, Koehler is overseeing the Chimney Hollow Reservoir Project, which involves constructing a 355-ft.-tall hydraulic asphalt concrete (HAC) core rockfill dam to ensure a water supply for over 400,000 Northern Colorado residents. Once completed, the reservoir will be the second and largest HAC rockfill dam of its kind in the United States.