Non-renewable groundwater resources: a ... - unesdoc - Unesco

Case studiesDevelopment and managementof groundwater: regional casesSaudi Arabia aquifersWalid A. AbderrahmanIntroductionMost of Kingdom of Saudi Arabia (Figure 1) is arid. The average annual rainfall ranges from25 mm to 150 mm (MAW 1988) compared to the average annual evaporation that ranges from2,500 mm to about 4,500 mm. The country’s socio-economic development has been supportedin large measure by its intensive use of groundwater including non-renewable fossil water.This paper focuses on the country’s management and use of non-renewable groundwaterfor satisfying its national water demands and the tools it uses to minimize negative impacts onthe aquifers. Also discussed are issues of sustainability and the possible impacts of climatechange on water demands and thus on the continued development of the country.Water resources in Saudi ArabiaGroundwater in Saudi Arabia is found almost entirely in the many thick, highly permeableaquifers of large sedimentary basins of the Arabian Shield (Figure. 1), (Burdon 1982; MAW 1984).The estimated groundwater reserves down to a depth of 300 meters below ground surface areabout 2,185 billion cubic meters (BCM). The average annual recharge is about three orders ofmagnitude less than that, or about 2,762 million cubic meters (MCM).Groundwater is supplemented by desalinated water and treated wastewater. Saudi Arabiahas become the largest desalinated water producer in the world. The total annual waterproduction from desalination plants has increased from about 200 MCM in 1980 to over1,000 MCM today (Al-Husayyen 2002). The present production represents about 50% of thetotal current domestic and industrial demands, and most of the rest is met from groundwaterresources.63