GROUNDWATER CHEMISTRY OF DOMESTIC WELLS IN THE SUNRISE ESTATES SUBDIVISION, LINCOLN, NE

The Sunrise Estates Subdivision is a residential area located east of Lincoln, Nebraska, immediately outside of city limits. The homeowners in this area are reliant on private, domestic groundwater wells for all their water needs. The area is underlain by the Dakota Formation, an aquifer known to contain highly saline groundwater at some locations around Lincoln. Two high capacity wells, with intentions of withdrawing groundwater to create lakefront property, have been installed in a new development a half mile east of the Sunrise Estates Subdivision. These higher capacity wells have caused concern for the possibility of saline groundwater migration upward as well as a lowering of the water table. The aquifer exists to a lesser extent in both thickness and proximity to the earth’s surface in the east and southeastern portions of the city, possibly decreasing the potential of salt water intrusion into the wells. Initial, baseline groundwater chemistry data has been obtained to identify present end members of the groundwater as well as assist with the determination of spatial and/or temporal variations in water quality should future assessment be desired. Seven private wells were sampled and analyzed for cations, anions, and stable ¹⁸O and Deuterium isotopes. Specific conductance values range from 428 µS/cm to 684 µS/cm. Average values for δ¹⁸O and δD are -7.9‰ and -53‰ respectively.