Prediction of the effect of pumping on al-wasia well field

Al-Wasia Aquifer is one of the major aquifers in Saudi Arabia which is found in the Central and Eastern regions of the country. Al-Wasia well field (62 wells) has been in operation since 1981 to supply water to Riyadh. It is located about 110 km north-east of Riyadh close to Riyadh-Dammam Highway. Amounts and rates of pumping from the well field have been changing during the last few years depending on water demand of Riyadh. The operation of the well field is examined under three different pumping stresses. The choice of a pumping pattern is according to the expected amount of pumped water from the well field to meet water demand of Riyadh. A two-dimensional regional ground water flow model (REGNLGW) is utilized to predict the expected water/piezometric levels in the well field due to the different pumping patterns up to the year 2010. The results of the simulation of the different pumping patterns show that piezometric level, in the year 2010, will not reach the critical depth of 300 m below ground surface. This depth is assumed critical because it is economically infeasible to extract water from depths greater than 300m.Corresponding Author: Dr. Saleh A. AlHassoun, Associate Professor Department of Civil Engineering, College of Engineering, King Saud University, P.O. Box 800, Riyadh-11421, Saudi Arabia. Email: shassoun@hotmail.co