Mississippi River Hydro Survey

KC District Lakes Hydro Survey

Missouri River Hydro Survey

Ohio River Harbor Dredge Survey

Red River of the North

Standing Bear Bridge

Vermillion-Newcastle Bridge

Weatherby Lake

U.S. Army Corps of Engineers

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Harlan County Lake Hydrographic Survey and Bathymetric Mapping

Harlan County, Nebraska

Harlan County Lake is located near the Kansas border in central Nebraska near the community of Alma. A dam on the Republican River created this large reservoir that not only provides flood control and a source for a wide-scale irrigation projects, but also a lucrative recreational market in the area. The lake has a surface area of 23,100 acres at the flood control pool with a drainage area of 7,164 square miles. There are 75 miles of shoreline on Harlan County Lake. The Kansas City District of the Army Corps of Engineers wished to have a sedimentation survey completed and a bathymetric map developed of the entire lake. Eisenbraun and Associates was commissioned to provide all of the hydrographic surveying, GPS control, and edited data for the development of the bathymetric map. The extreme variations of shoreline features and the weather conditions of the area at the time of the survey created challenges for E/A crews to complete the project in the aggressive 45 days allowed for the field survey. Eisenbraun and Associates used their breadth of hydrographic equipment to competently survey Harlan County Lake. Approximately 10 percent of the hydrographic survey on the west end of the lake was accomplished by a crew member in chest waders pushing a 14-foot jon boat through the swampy delta region, while a second crew member operated survey equipment in the boat. An 18-foot boat with a jet motor was used for surveying the shallow bays, and E/A’s 26-foot hydrographic survey vessel was used on the remaining open areas that reached depths of up to 80 feet. On calm days, crews worked double shifts to take advantage of favorable conditions. The entire lake was surveyed with ranges on a 100 foot spacing and data captured every 25 feet in order to create the DTM and bathymetric map. To complete the project, Eisenbraun and Associates had Torres Engineering of Kansas City assist with land surveying aspects of the project and MJ Harden Associates of Kansas City assist with the final map production. The project was completed on schedule and within budget.