The Wadi Samail is located on the southeast Batinah coast of Oman and is underlain by an unconfined aquifer which is a major source of water supply for Muscat, the capital of Oman, and surrounding areas. Historically, the aquifer has been exploited through dug wells, and the development of several new well fields for municipal supplies have considerably increased the rate of exploitation of the aquifer. The increased pumping rates have resulted in salt-water intrusion, and consequently, in the deterioration of the water quality in many wells near the coast. SSP&A studied the hydrologic effects of alternative-development schemes for the Wadi Samail aquifer using a groundwater simulation model.
The model used to determine the behavior of the groundwater system was a vertically-averaged finite difference model that simulates the areal flow of fresh water and salt water separated by an interface. The alternatives studied included the installation of galleries at two distances from the coast, the development of spreading basins to increase aquifer recharge and groundwater production from galleries, and the elimination of garden pumpage near the coast to increase fresh-water levels and prevent salt-water intrusion.