The water table aquifer on Dauphin Island, Alabama, is made up of sand and clay layers and has low chloride content, except near the coast. Groundwater on the island has high iron concentrations in some areas. A groundwater flow model was used to study the aquifer's behavior, showing that it can sustain pumping of 0.6 million gallons/day without seawater intrusion. The model was calibrated using data from test wells, aquifer tests, and rainfall measurements. The study found that the aquifer can handle withdrawals without harming the environment.