DGS issues report on groundwater modeling in southern New Castle County

The Delaware Geological Survey (DGS) released a new technical report entitled Simulation of Groundwater Flow in Southern New Castle County, Delaware, which was prepared by Changming He and A. Scott Andres of the DGS.

DGS Report of Investigations No. 77 is a preliminary step in developing a detailed understanding of the subsurface hydrology and evaluating groundwater availability in major aquifer systems beneath southern New Castle County and parts of northern Kent County, which are expected to have greater demands for groundwater in the next 20 years due to population growth.

With increases in computational speed and power, numerical models have been increasingly used in aquifer characterization, water-resources management, and resource optimization. This report documents the results of a study in which a three-dimensional numerical model was used to simulate groundwater flow in the Columbia (water table), Rancocas, Mt. Laurel, combined Magothy/Potomac A, Potomac B, and Potomac C aquifers and intervening confining beds.

In addition to providing a focus for compilation of existing hydrogeologic information, the model simulates, using limited data, the current groundwater levels due to pumping, and predicts changes in flow and groundwater levels due to changes in pumping.

Compilation and review of data used for model input revealed major gaps in hydraulic properties, pumping, aquifer and confining bed geometry, and water-level data and indicated a critical need for additional information required to support planning of future water supplies and wastewater disposal, and management of water-dependent environmental resources.

Recommendations for improving our understanding of groundwater availability are presented in the report. In addition, model results indicate that new monitoring wells should be installed in deep aquifers in this area prior to the advent of increased groundwater use.

The report fulfills part of the DGS's mission to understand hydrologic systems and to advise, inform, and educate Delawareans about the results of such investigations for use in such topics as water resources, agriculture, public health, economic development, land-use planning, geologic hazards, environmental protection, energy and mineral resources, emergency management, and recreation.

Report of Investigations No. 77 is available in PDF format from the DGS website. For additional information, contact the DGS at 302-831-2833 or via email at [delgeosurvey@udel.edu].

For questions and information, contact DGS at
delgeosurvey@udel.edu, 302-831-2833