THE EASTERN NEBRASKA WATER RESOURCES ASSESSMENT (ENWRA)

The Eastern Nebraska Water Resources Assessment (ENWRA) is a cooperative effort involving ten local, state, and federal agencies to develop a three-dimensional geologic framework and water budget for the glaciated region, or eastern 1/5th of Nebraska. This region contains 70 percent of the state's population but is most limited in terms of the state's ground water supplies. Locally governed Natural Resources Districts (NRDs), charged with ground water management in Nebraska, seek to improve their management plans in response to growing populations, hydrologic drought, and new conjunctive management laws. Detailed mapping and characterization is necessary to delineate aquifers, assess their degree of hydrologic connection with streams and other aquifers, and better predict water quality and quantity.

Pilot studies at three different sites are being conducted to test the effectiveness of potential investigative tools. Sites are located near Firth, Ashland, and Oakland, Nebraska, each representing a different hydrogeologic setting. The pilot studies, initiated in 2006, are planned to continue for three years and will be used to assess the feasibility of applying the tools to broader areas. In year one, helicopter electromagnetic (HEM) surveys were completed over approximately one township at each pilot study site. Test hole drilling, borehole geophysics, and time domain electromagnetic (TDEM) surveys were conducted for ‘ground truth' data to support the HEM interpretations. In years 2 and 3, additional tools supporting water quality studies, ground water age dating, hydrologic monitoring, and estimation of recharge to aquifers will be tested at the sites. The long-term vision is to apply the suite of tools developed in the pilot studies to provide data, interpretations, and models for improved water resources management.

This is a large, multi-faceted study requiring successful coordination and planning between multiple levels of government. Public involvement and funding of water resources studies at the local, state, and federal levels have been and will continue to be vital to its long-term success.