Assessment and Management of a Desert Basin in Kuwait

ABSTRACT

The study area, Umm Gudair, is located in the southwest corner of Kuwait. It occupies an area of ≈ 4.84 × 10⁹ ft². The brackish ground water is derived from the two main aquifers within the Cenozoic sequence. These are: the Kuwait Group aquifer (Miopleistocene) and the Dammam aquifer (Eocene). In the study area, the two aquifers are treated as a single reservoir Forty-one production wells, locally called “dual completion wells” were finished in the aquifers. This research identifies the hydrogeologic properties and the water quality of the aquifers. In addition, the article discusses the application of the surface electrical method Schlumberger configuration to correlate and delineate the areal distribution of the apparent resistivity with the aquifer salinity, and the occurrence of a water-bearing formation. The results will be use for assessment and management of the groundwater reservoir The water quality of the two aquifers is relatively poor The T.D.S. ranges between 3,130-4,740 mg/L. The hydrochemical facies are calcium-sodium cation facies and chloride-sulphate anion facies. The ground water is classified as a NaCl water type, however two genetic water types are identified: the MgCl₂ and CaCl₂ are of marine origin and are old marine formations. The aquifer is semiconfined to confined The average transmissivity, which increases toward the N and N-E, is 20,965 Igpd/ft. The geophysical studies conducted along seven profiles with 19 vertical electrical soundings reveal three distinct layers. The first layer is composed of dry gravel and has a resistivity of 80–220 m. For the second layer, the resistivity ranges between 5–9 Ωm. It is assumed to be a clayey layer saturated with brackish water; whereas the third layer corresponding to a limestone formation, has a resistivity of 25–700Ωm. The apparent resistivity decreases in the direction of the increasing salinity From the flow-net analysis, the amount of ground water entering the aquifer along the border with the Saudi Arabia is 2.3 × 10⁶ Igpd, while the average daily production from the Umm Gudair field is 13.5 × 10⁶ Igpd, It is obvious that the daily abstraction rate is higher than the daily flow toward the aquifer Therefore, in the future, if the daily abstractions continue to exceed the daily water flow through the aquifer a serious decline in the water level will result.