The Parker Water and Sanitation District constructed the 72,000-acre-foot Rueter-Hess Reservoir to serve the drinking water needs of Douglas County, one of the fastest growing US counties. Drexel, Barrell & Co. provided 1st order surveys of the elevations on the dam and inside the 78-inch diameter outlet works piping located beneath the dam. This required our surveyors to obtain precise elevations while over a quarter mile from the entrance, and where the only light available was from headlamps and flashlights. DBC continues to monitor the Rueter-Hess Reservoir and Dam annually.