GROUNDWATER VULNERABILITY AND THE REUSE OF WATER, WITH REFERENCE TO SAUDI ARABIA (pp. 179-184)
Abstract: It is noted that an integrated water supply system incorporating surface water, groundwater and recycled water is essential and that in the denition of groundwater resources consideration should be given to the inclusion of some brackish and saline waters. The abstraction of groundwater in Saudi Arabia, irrespective of quality, is a mining operation so that increasing emphasis will need to be placed on desalinization and the recycling of sewage and industrial waste waters. Aspects of the reuse of such waters are discussed with respect to aquifer protection and aquifer value as a storage medium.
MANAGEMENT OF GROUNDWATER RESOURCES IN EASTERN SAUDI ARABIA (pp. 185-210)
aWater Section, Center for Environment and Water, Research Institute, King Fahd University of Petroleum and Minerals, Saudi Arabia; bHydrogeology Research Group, School of Geological Sciences, University of Birmingham, Edgbaston, UK
Abstract: Effective management of groundwater in arid countries, such as Saudi Arabia, is an important factor in sustainable development. A regional numerical simulation model of a multi-aquifer system including the Dammam and Umm Er Radhuma (UER) aquifers was developed to assess the behaviour of the aquifer system under long-term water stresses. The model was utilized to predict the responses of the aquifer system under three alternative pumping schemes over a planning horizon of 31 years (1995–2025). Model results postulate that dewatering of the Dammam aquifer will occur at low productivity sites and along the outcrop with the current trend towards increasing abstraction. The UER will exhibit signicant cones of depression at large irrigation projects. Aquifer dewatering and drawdowns will be minimal with the conservation alternative. This management scheme should be adopted for the future development and protection of groundwater in the province.
UPCONING AND SALINE WATER INTRUSION AND THE NEED FOR WATER CONSERVATION IN THE LOWER PART OF WADI FATIMAH, WESTERN SAUDI ARABIA (pp. 211-226)
aFaculty of Earth Sciences, King Abdulaziz University, Saudi Arabia; bDepartment of Geology, College of Science, King Saud University, Saudi Arabia
Abstract: Shallow aquifers were exploited in western Saudi Arabia a long time ago in history. In the last ve decades, and under the conditions of an increasing supply of water, many new wells were drilled at relatively deeper intervals than the hand-dug wells of the time. In the downstream part of Wadi Fatimah, and over time, more saline water has been brought up in a number of wells. Overexploitation of groundwater for industrial and agricultural purposes has led to the appearance of two phenomena responsible for the salinization—upconing and saline water intrusion. Upconing occurs in separate pockets while saline water encroachment affects the lower part of Wadi Fatimah and the area towards the Red Sea coast. This article deals with the identication and delineation of areas affected by each of the two phenomena. The methodologies used in this work are mainly hydrogeological and hydrochemical. Resistivity surveys helped in delineating the fresh water–saline water interface. Methods to control upconing and saline water intrusion are suggested to safeguard the aquifer from further contamination. Effective conservation measures are recommended for the protection of groundwater resources in Wadi Fatimah.
GROUNDWATER RIGHTS AND LEGISLATION FOR SUSTAINABLE DEVELOPMENT IN ARID REGIONS: THE CASE OF SAUDI ARABIA (pp. 227-235)
Abstract: The main objective of this article is to shed light on an important issue of water conservation—groundwater rights and legislation. Principles of groundwater rights are detailed and their applications to major aquifer systems, groundwater basins and wadis are discussed. Legislation and the clarication of water rights are vital for the sustainable development of groundwater. They are urgently needed in Saudi Arabia in particular and in all areas where demand exceeds supply. Legislation is one of the main pillars upon which any conservation policy is built. In this article a model is suggested for groundwater allocation in aquifers shared by more than one state.
HYDCOND: A COMPUTER PROGRAM TO CALCULATE HYDRAULIC CONDUCTIVITY FROM GRAIN SIZE DATA IN SAUDI ARABIA (pp. 237-246)
Abstract: Hydrogeologists always look for reliable techniques to determine the hydraulic conductivity of the aquifers with which they are concerned, for better groundwater management and conservation. The use of grain size distribution for unconsolidated aquifer materials is considered feasible and sound. Several empirical equations to calculate hydraulic conductivity using grain size distribution are well established in the literature. The present paper describes a computer program, HYDCOND, which is designed to calculate hydraulic conductivity using grain size data. In addition, the program calculates grain size statistics and classies the aquifer materials in terms of their main size percentage. HYDCOND is menu-driven, interactive and user friendly program. It was tested extensively and successfully using materials from Minjur aquifer in central Saudi Arabia. The results were found to be reliable and comparable to those obtained using other, costly techniques. HYDCOND can be implemented successfully to calculate hydraulic conductivity in all types of aquifers in Saudi Arabia and other regions of the world.
ENERGY AND WATER IN ARID DEVELOPING COUNTRIES: SAUDI ARABIA, A CASE-STUDY (pp. 247-255)
Abstract: In Saudi Arabia, where water resources are limited, the availability of energy resources, including petroleum, natural gas and electricity, helped in solving the challenge of satisfying rapid and substantial increases in water demand for drinking and industrial and agricultural purposes. Thirty-ve major dual-purpose multi-stage ash distillation (MSF) and reverse osmosis (RO) desalination plants were constructed on the Red Sea and Gulf coast to produce drinking water. The process energy requirements for MSF and RO range between 19.5 and 38 kWh/m3, and 0.5 and 9 kWh/m3, respectively. The MSF plants produce about 20% of the total national electricity production. About 85 000 wells were drilled to satisfy the increasing irrigation water demands. The energy requirements to pump 1 m3 from wells range between 0.4 and 0.8 kWh. The adoption of advanced technologies is continuing to reduce power consumption and water demand to conserve energy and water, and to minimize negative impacts on the environment.
INVESTMENT NEEDS AND PRIVATIZATION OF WATER SERVICES IN SAUDI ARABIA (pp. 257-260)
Abstract: The article outlines the dynamics of the privatization of water supply and sanitation services in Saudi Arabia. It also gives a summary of the projected requirements of desalination plants’ capacity and the estimated capital investment needed for water supply and sanitation services. It gives a summary of public and private initiatives to privatize water services in Saudi Arabia.
COMPUTERIZED AND DYNAMIC MODEL FOR IRRIGATION WATER MANAGEMENT OF LARGE IRRIGATION SCHEMES IN SAUDI ARABIA (pp. 261-270)
Abstract: Irrigation water consumption in Saudi Arabia represents about 90% of the national water use, and the limited groundwater resources are the major water supply for irrigation. Improper irrigation water operation accounts for signicant water losses in some large irrigation schemes. Consequently, the use of advanced techniques in irrigation operation and scheduling is essential for the reduction of irrigation water demands. A new and original Computerized and Dynamic Irrigation Water Management System (CDIWMS) was developed for automatic and/or manual irrigation operation and scheduling of irrigation schemes containing a large number of elds. The CDIWMS is supported by a comprehensive and dynamic database management system. The system performs several functions, including the dynamic modication of eld information and operation conditions such as the delaying or suspension of irrigation, and the setting of elds for cutting or harvesting. The model was tested and implemented successfully in several large irrigation schemes in the Kingdom of Saudi Arabia using full automation and manual operation. The implementation of the CDIWMS has resulted in a saving of more than 25% of the water, energy and costs of operation and maintenance, and in an increase in agricultural production.