Tri-S Environmental was contracted to evaluate the effects of groundwater pumping on drawing in seawater to the City of Punta Cana due to the large increase in population. Rapid economic growth and increased urbanization have also affected environmental quality and placed strains on the water resources base. The engagement entailed a basin-wide hydrologic assessment which included groundwater recharge, source determination, pumping, well inventory and future water use aspects. Punta Cana is located in the eastern most province of the Dominican Republic which has undergone vast development over the last ten years with large resorts and a dozen professional golf courses.