Fresh-water Modeling for Saudi Arabia

Transcription

1 For office use only T1 Team Control Number For office use only F1 1 T2 T3 T4 Problem Chosen B F2 F3 F Mathematical Contest in Modeling (MCM/ICM) Summary Sheet Fresh-water Modeling for Saudi Arabia Water is the most important natural resource on earth. Life on earth would not have been possible without water. It is used for all the domestic purposes as well as industrial purposes. The industrial development of a country depends on its water supply. Saudi Arabia, being an arid country, faces acute water shortage. The ground water resources available there are very less. Most of the water supply comes from desalination plants which purify sea water to get pure water. These desalination plants are located near the sea shores and huge transportation infrastructure is required to feed the water requirements. The current usage of water in Saudi Arabia includes agriculture sector, industries and domestic chores. Our model discusses the current usage of water in Saudi Arabia and proposes amendments to currents water usage. New methods to feed the water requirements have also been discussed in the study. In this paper, we analyze the acute shortage of water being faced by Saudi Arabia and developed a model to describe the same and propose new policies to meet the projected water needs of Saudi Arabia in This paper also discusses the present water consumption of the country. The cost of present policies in the country and the policies proposed has also been discussed in this paper.

2 Introduction 2 Saudi Arabia, officially known as the kingdom of Saudi Arabia, is the largest Arab state in Western Asia by land area. Over recent years, the Kingdom of Saudi Arabia has been confronted with what many consider its greatest challenge: achieving modernity without surrendering its heritage, faith, or culture. Seventy-five years ago, Saudi Arabia did not exist; today, it is a nation marked by sophisticated political, legal, and financial systems, with a culture rich in history and deep in faith. Wealth from oil revenues made it possible for the government to develop all sectors of the economy. The growth of cities, increase in the population and the rise in the standards of living caused domestic and industrial water consumption to increase many folds. The constant pressure on the country s water resources made it necessary to develop both the conventional (surface and ground water) and the unconventional water resources (desalination of sea water). In view of increasing the supply and improving the efficiency of water use in various sectors, more than 230 dams for different purposes were constructed to utilize surface water which is available in some regions of the country. Existing huge aquifers were also analyzed and utilized for different uses. With respect to the desalination of sea water, many stations were built on Red Sea and the Gulf, thereby making the Kingdom the largest producer of fresh water from sea water in the world. Despite the astounding efforts made by the government of Saudi Arabia, the consumption of water has reached an alarming level. The demand for water has grown substantially against a scarce and dwindling water supply. The critical issue is how to reconcile the rapidly rising demand with scarce and depletable resources. Consequently, it seems imperative to encourage the rational consumption of water and its management by all sectors on a scientific basis to ensure its continued availability and future conservation. Furthermore, there is a need to develop appropriate water quality standards and to enforce rules and regulations relating to these standards. The advanced technologies are needed to develop water resources of the country and possibly tailor the measures to be adopted to consume them efficiently and conserve this precious resource with the national spirit.

3 Water Demand (million cubic metres) Team # Water Demand in Saudi Arabia 3 The figure 1 demonstrates the distribution of the water demand among various practices in Saudi Arabia over last 30 years and predictions up to Total Municipal water use in Saudi Arabia has been estimated at 2.1 billion cubic meters per year in (2004) or 9%, Agriculture accounts for 88% and industry for only 3%. Demand has been growing at the rate of 4.3% per annum ( ). Household water consumption is around 260 litres per capita per day. Composition of Water Demand in Saudi Arabia Industrial Demand Domestic Demand Agricultural Demand Total Demand Fig.1

4 Available water resources 4 Water resources in Saudi Arabia can be classified into four types: surface water, desalinized water, ground water and treated waste water. Surface water Saudi Arabia has no reliable and adequate surface-water sources. It has no perennial rivers and precipitation is extremely low. The average rainfall is about 90 mm per year. This average, however, hides wide regional fluctuations. The rainfall varies from 20 mm per year in the north to 500 mm in the south. Rainfall is also extremely variable in time. For instance, the Riyadh area received 13.5 mm of rainfall in 1966, but in 1967 it received mm (Kalthem 1978). Nearly all precipitation occurs between the months of November and April, while the rest of the year is dry and hot. During summer months the average daily temperature exceeds 100 F (38 C) and often reaches 120 F (49 C) in the central, western, and eastern parts of the country. Due to the desert climate, a large percentage of rainfall evaporates. According to one estimate, 20% of rainfall evaporates immediately and another 50% is evaporated through water runoff in wadis (dry water courses), (Kelly and Schnadelbach 1976). In Saudi Arabia, surface runoff occasionally occurs during the rainy seasons when there are rain storms. Estimates of the amount of runoff water range between 2,000 million and 2,400 million m3 (mcm) per year. Most of the runoff occurs in the coastal areas and highlands of the southwest, where rainfall is relatively abundant and regular. Surface water is available with an estimate of about 2045 million cubic meters per year comes from rainfall and is found pre-dominantly in the west and south-west of the country. Dams are used to capture surface water after frequent flash floods. More than 200 dams collect an estimated 16 billion cubic feet of runoff annually in their reservoirs. Some of the largest of these dams are located in the Wadi Jizan, Wadi Fatima, Wadi Bisha and Najran. This water is used primarily for agriculture and is distributed through thousands of miles of irrigation canals and ditches to vast tracts of fertile land that were previously fallow. Ground Water Ground water is the most important source of water in Saudi Arabia. It comes from two types of aquifer: renewable and nonrenewable. The first type, shallow aquifers, contains a renewable water supply charged by infiltration from rainfall and surface-runoff water that flows over wadis. The renewable ground water is estimated at around 950 mcm/year. The other type, deep aquifers, contains a reservoir of water formed thousands of years ago when water was

5 trapped in sedimentary rocks such as limestone and sandstone. These deep aquifers receive negligible or no recharge and therefore store nonrenewable and depletable ground-water resources. The depth of these aquifers ranges between 100 and 500 m and may exceed 1,000m in some areas. Nonrenewable ground-water reserves were estimated at 500,000 million m3, of which 67% is stored in seven major aquifers, while a series of secondary aquifers holds the rest. 5 The quality of ground-water resources in Saudi Arabia varies from area to area, and only in a few areas is it of an acceptable drinking quality [contains less than 1,000 parts per million (ppm) of total dissolved solids (TDS)]. Most ground water in Saudi Arabia is classified as brackish, which contains over 1,000 ppm (Wojcik and Maadhah 1981). This water is unsuitable for human consumption or for irrigating non-salt-resistent crops. Some desalination methods are required to remove most of its salt content before it can be used. Usually, desalinated seawater is blended with brackish water to produce potable water in major cities. Desalinated seawater Desalination is the process that produces potable water from brackish sea water. The Saline Water Conversion Corporation (SWCC) operates 27 desalination stations that produce more than three million cubic meters a day of potable water. These plants provide more than 70 percent of the water used in cities, as well as a sizeable portion of the needs of industry. With 30 seawater desalination plants producing 45% of its water for household and urban use, Saudi Arabia is the largest water producer using desalination in the world since the 2000 s. Its involvement in the global production of desalinated water has reached 17.4%, placing the Kingdom before the United States (16.2%) and before another main player of the Gulf, the United Arab Emirates (14.66%). In a smaller area, concerning the Gulf Cooperation Council (GCC), the involvement of Saudi Arabia has reached 45.5% of the regional production of desalinated water, also placing the country before the United Arab Emirates (38.15%). Seawater desalination is an expensive operation that requires a large amount of money to construct, operate, and maintain. For example, the Saudi government has spent 33.5 billion riyals (U.S. $1 = 3.75 Saudi riyals) operating desalination projects between 1970 and 1985 alone (Annual 1985). In addition, the TDS level in the Red Sea and Arabian Gulf (which varies between 40,000 and 60,000 ppm) is much higher than that of other seas and oceans (Wojcik and Maadhah 1981). For this reason, water desalination in Saudi Arabia is more expensive than in other countries using the same methods of desalination. Moreover, considering the fact that the operational life of a desalination plant is in the range of years, Saudi Arabia will require large amounts of expenditure to replace worn-out plants. This will impose a heavy burden on the country's financial resources, especially during a period of declining oil revenues.

6 Reclaimed Wastewater In an arid country where natural water resources are limited, reclaimed wastewater can be an important potential source of water supply. In addition, the treated wastewater has several advantages over other sources of water: It is cheaper than seawater desalination; it minimizes pollution; and it is a good nutrient source for landscape and farm irrigation. 6 There are 33 wastewater treatment plants with a capacity of 748 million cubic meters per year, and 15 more are under construction. Much of the treated wastewater is being reused to water green spaces in the cities (landscaping), for irrigation in agriculture and other uses. Water Sources Water supply (in mcm) as per 2003 Surface Water 5,000-8,000 (only 2,230 is available for use) Groundwater Resources Groundwater Recharge Desalination 1,050 Treated wastewater 240 2,269,000 (84,000 renewable groundwater in shallow aquifers) 3,598 (1,196 to shallow aquifers and 2,762 to deep aquifers in the Arabian Shelf) The variation in the water supply to satiate the demand of water resources is shown in the table below: Water Source Treated Wastewater Effluents Desalination Surface Water and Renewable Groundwater Non-renewable Groundwater Total

7 The Model 7 Our model for an efficient and feasible water strategy proposes some new and alternative ways of sourcing fresh water resources. Along with them, the model also emphasizes different ways to utilize the available water resources in the optimum way. Proposed modifications: (1) Mining fresh water icebergs from Antarctica to Saudi Arabia For the thirsty areas of the world, using Antarctic icebergs is a very attractive possibility. The abundance of icebergs has long been recognized (annual yield of about 1,000,000 million cubic meters). If, let s say, even 10 percent of the annual yield is used as a fresh water source economically, it is enough to satisfy the water demands of an urban population of 500 million (with a usage of 200 m 3 per person). The potential direct economic impact of fully exploiting 10 percent of the annual yield is estimated to be as much as 10 billion USD annually. Past exploration of the Antarctic has indicated that by March of every year, most of the tabular icebergs naturally formed from the ice-shelf discharges are accessible for acquisition and export operations. The total area of sea ice formed and thawed each year is so huge that even the complete removal of the total annual iceberg yield will have little climatic effects. The estimated total continuous yield of icebergs from the Antarctic is 1.2x kg per year, which could be harvested beneficially and without depletion or environmental damage in the Antarctic. The total yield is equivalent of 1.2x of high quality fresh water, which would be adequate to satisfy the needs of an urban population of 4 to 6 billion people at 200 to 300 of water per capita per year. This total annual water resource might alternatively be used to irrigate 0.6 to 1.0x or more of agriculture. If the total potential iceberg resources were exploited (1.2x kg per year), the transporting of the icebergs would ultimately involve an annual business of about $10 billion per year (at about $10 per k. or acre-ft). The total cost of delivery for wholesale distribution of high quality fresh water would be about $30 billion to $50 billion per year. The savings over desalting or long-distance interbasin transfer could ultimately amount to $50 billion to $70 billion per year ($50 to $70 per acre-ft). The

8 complete efficient harvesting and full exploitation of the Antarctic iceberg resources should not be expected for many years. 8 There does not appear to be anything in the harvesting of ice from the Antarctic that is basically in conflict with the Antarctic Treaty, as long as the environment is properly protected. However, before large scale operations are taken, it would seem appropriate to organize a planning conference for all concerned nations on order to arrive at an agreement about rules of harvesting that would ensure protection of the environment and opportunities for all to share in the benefits. (2) Conservation of water resources The costs of developing new sources or expanding existing sources are getting higher and higher. Therefore, saving water rather than the development of new sources is often the best source of water. Water demand management is seen to be the preferred alternative to meet increasing water demand in Saudi Arabia; this will improve efficiency and sustainability. The following guidelines can reduce the water wastage by a substantial ratio. 1. Reducing the subsidies by the Government on water resources and changing the price of water to the level that consider the environmental conditions of Saudi Arabia, the real cost of the production of each cubic meter of water by the Government, the high living standard of people, the price of other commodities and the price of water of some world cities. The new proposed prices will help along with allocated money by the Government to reduce water loss rate from the network. 2. Introduce effective and efficient national water campaign to rationalize water use by consumers, based on the previous results of the previous campaign, taking into account, the women, children and house mates. Introduce educational curriculum to raise the awareness of the school students. 3. Apply effective policies, monitoring measures, penalties in order to control the miss use of water. 4. The use of modern devices that minimize the wastage of water. Water conservation methods like leak detection and reduction of illegal connections. 5. Installation of two separate distribution systems of Municipal water: One is potable and other is not, but destined to irrigate parks, gardens, and other tourisms facilities.

9 (3) Improvements in Desalination Plants Up until recently, 90 percent of all the water desalination plants in Saudi Arabia ran on oil or natural gas as the source of energy, which is economically unsound. A cubic meter of water costs between 40 and 90 US cents to produce, depending on the price of fuel; it would be more profitable to simply sell the oil to foreign trade partners. Currently, the Kingdom uses a tremendous amount of energy 1.5 million barrels of oil per day to provide power to the country s 30 government-operated water desalination plants. As oil price have risen, the cost of desalinated water has increased as well, making this water production method even more economically unsound. 9 Hence, the Kingdom s new reliance on the best alternative to fossil water: desalinated water, powered by the sun, not by oil. The country could consider nuclear power as another option, but this option would entail the political problem of introducing nuclear technology to the unstable Middle East. Reliance on nuclear power would also make Saudi Arabia dependent on uranium imports. Solar power, by contrast, is harmless, both politically and environmentally. Fortunately, the Saudis can afford to build many solarpowered desalination plants, enough even to completely support self-sufficiency in food production. To build and the plants requires money and energy, and the Kingdom has plenty of both. In terms of the construction costs, Saudi Arabia would need to build enough plants to increase its water output by a factor of five to keep up with their annual two percent population growth. The cost for such an endeavor would be approximately US $200 billion. Producing the planned 15 billion cubic meters of water per year will require about 60 terawatts of energy annually, which means that about US $300 billion of 1 kilowatt-rated power photovoltaic panels are necessary. Considering that Saudi Arabia has been reaping a surplus of US $100 billion in oil trades every year, it can definitely afford to build and run enough new water desalination plants. Furthermore, this cost estimate reflects the most expensive technology available as of 2008; as technology becomes more advanced with time, the cost could decrease. Building new solar power water desalination plants is strategically smart because it stops the bleeding of oil from the natural reserves while enabling the country to keep up with the needs of a growing population and increasing urbanization. With enough water production, Saudi Arabia will not have to be at foreign countries mercy for food imports. Furthermore, the Kingdom could benefit from pursuing this green technology by earning international recognition as one of the environmentally friendly developed

10 countries, exporting water throughout the Middle East, selling desalination technology, and guaranteeing water security to citizens in rural areas who rely on the whims of unreliable trucked water sellers. With a sustained push for the development of hightech water desalination plants, Saudi Arabia may well become not only an oil power, but a water power as well. 10 (4) Optimum use of resources The major use of water in Saudi Arabia is in agriculture sector. Agriculture sector in Saudi Arabia constitute the production of wheat which require huge amount of water. Instead of promoting wheat production and buying wheat from the farmers (and therefore wasting valuable water), a preferable method would be to import wheat from other countries, indirectly saving a lot of money which would otherwise have been used to produce fresh water. The same process can also be applied to all other agricultural activities which consume a lot of water. Fig.3 Seeing the large amount of water usage in the wheat production, similar measures have recently been taken by the Government to reduce the wheat production (Fig.3). The government is reducing its subsidy on wheat by 12.5% each year. This measure had a positive effect on the water demand, and instead of increasing with the increasing population, the water demand by the agricultural sector reduced a little.

11 Although the total food dependence may sound extreme, it is very rational. Since the introduction of government subsidies, food production has relied almost entirely on fossil water, or deep groundwater extracted from ancient aquifers in an energyintense process. Unfortunately, using fossil water for any longer makes no business sense for multiple reasons. First, Saudi Arabia is capable of importing all of its wheat necessities using oil money. As long as food-exporting countries will trade for Saudi oil, the richest Arab nation has no reason to lose money by making its own wheat. Second, the kingdom can sell the very oil used to run the water plants to other countries and bring in more money. Finally, fossil water is realistically nonrenewable in the span of our human lives, so Saudi Arabia would do well not to entirely deplete its ancient fossil aquifers. According to estimates, about 70 percent of these aquifers, more than what is considered naturally recoverable, have been depleted already from the increased water production in the past decades. Though simply buying water directly with oil money would seem to be an obvious solution, even the oil-rich Saudi Arabia cannot count on its oil reserves forever. This means that reliance on oil for water and food itself, albeit convenient, is shortsighted. Even Saudi Arabia should look for alternative sources for water and food. 11 Conclusion: The management of water resources is an important issue for the well-being of the society. As the population of the country continues to grow, a greater quantity and diversity of water will vex water resource managers. In order to adequately tackle with such problems, water resource managers must understand the specific characteristics of places in their management plans. Saudi Arabia has been facing a serious water problem due to rapidly growing demand and limited supply. This problem has been aggravated by the existence of wasteful, inefficient consumption patterns induced by too much emphasis on water-supply development and a nearly total neglect of efficiency and management of water use. Unless drastic and immediate conservation measures are taken, water demand will increase rapidly, creating an accelerated use of and depletion of ground-water resources. For an arid country such as Saudi Arabia, ground water is the most important water resource. Its fast depletion may create an acute water shortage with serious social, economic, and environmental implications.

12 What is urgently needed is the formulation and implementation of an integrated watermanagement and water-development program that emphasizes conservation and efficient use of the existing water supply. Such a program must seek the achievement of three goals: (1) Using less water; (2) Using water more efficiently; and (3) Developing new and less expensive water sources. 12 References: [1] J. L. Hult, N. C. Ostrander. Antarctic Icebergs as a global fresh water resource [2] Walid A. Abderrahman. Groundwater Resources Management in Saudi Arabia [3] Franck Galland. Saudi Arabia: when water means opportunity [4] Khodran Hamdan Al-Zahrani. Water Demand Management in the Kingdom of Saudi Arabia [5] Abdulla Ali Al-Ibrahim. WATER USE IN SAUDI ARABIA; PROBLEMS AND POLICY IMPLICATIONS [6] Erika Lee. Saudi Arabia and Desalination <