PROCEEDINGS OF THE 3RD INTERNATIONAL CONFERENCE ON ENERGY AND DEVELOPMENT - ENVIRONMENT - BIOMEDICINE Water Resources Management in Karkheh Basin-Iran AMIR HAMZEH HAGHIABI1 , NIKOS E. MASTORAKIS2 1-Department of water engineering Lorestan University Khorramabad, Lorestan Province IRAN [email protected] 2- Technical University of Sofia, BULGARIA– also with the WSEAS Research Department, WSEAS, A.I.Theologou 17-23, Zografou, 15773, Athens, GREECE Abstract: - Karkheh basin is located in the semiarid and arid regions of Western Iran, an area with severe water scarcity. 70% of rainfall is directly evaporated. The potential annual evaporation of the southern and northern regions is 3,600 mm 1,800 mm, respectively. Agriculture plays an important role in the economy of the basin. In the present situation, 3.9 bm3 of water are used for irrigating 378,164 ha of irrigated agriculture (horticulture and field crops), and surface water and groundwater resources provide 63 percent and 37 percent, respectively, of this volume. Of the irrigated area, 76.5% is under cereals (wheat and barely), 23% under pulses, and 0.5% under cultivation of forage, orchards, melons and vegetables, and oil seeds. The area is particularly low in terms of yields, productivity and incomes. Irrigation efficiency in the basin is 28-36 percent and the overall Crop Water Productivity in the basin is about 0.55 kg/m3. In this paper, the specifications of the Karkheh Reservoir Dam & Hydroelectric Power Plant as the biggest dam in history of Iran with total volume of reservoir 7.3 Bm3 and Karkheh irrigation and drainage network project are illustrated. Also the situation of water availability in the basin, surface and groundwater potential and some aspects of water resources management in the basin are considered. Key-Words: - Karkheh-Water Resources-Zagros - Iran-Basin- Management 1 Introduction operations in Iran, which is used to protect water Water resource management is of global and soil, dates back to some 50 years ago. significance as it plays a key role in the The country's population growth is continuous. socioeconomic development of all nations. People are increasingly in need of more and more Attention to water supplies for the agricultural and water either for drinking purpose, or for farming, industrial sectors through construction of numerous industry or other means of their food security, or for dams and development of the water and sewage social welfare and health matters. Therefore, while sectors point towards this sector's growing the amount of the produced water is almost usually importance. The water sector is closely connected the same, the consumption is gradually increased not only to production and technology, but to the and the production-consumption ratio has always preservation of the general health and hygiene of had a declining trend. society and environment as well. A useful index is proposed in the world to estimate On account of the fact that Iran is situated in a the conditions of a country's water resources. In this highly pressurized belt in the world, precipitation is index the volume of renewable waters of a country limited, so that the average annual precipitation in is divided by its total population at any stage and by the country is about 250 mm, only about one third to this method they announce the approximate water one quarter of the world average for rainfall. reserves of that country. According to world statistics, Iran with more than Consequently, regardless of rainfall declines in ten million hectares of cultivated land under various years and in view of our global, irrigation ranks seventh in the world. At the same geographical and climatic conditions which have put time, more than 8 million hectares of agricultural us in a dry area, we have a country suffering from lands in Iran is subjected to dry farming. Watershed water inadequacy and meanwhile are moving toward a chronic water shortage. This totally differs ISBN: 978-960-474-148-9 114 ISSN: 1790-5095 PROCEEDINGS OF THE 3RD INTERNATIONAL CONFERENCE ON ENERGY AND DEVELOPMENT - ENVIRONMENT - BIOMEDICINE from the question of drought. This is what in my 5.08 million ha (Mha), out of which only 1.07 Mha opinion could only be called a serious crisis we are is irrigable and 0.9 Mha is suitable for rain fed to face, while it's getting worse day by day. agriculture. Out of total cultivated area, about 72.5 In most parts of Iran, this limited precipitation is % are under cereals (wheat and Barley), 17.5 % confined mainly to cold and winter seasons, and under pulses, and rest 10 % is used for the cannot be directly used by plants especially for cultivation of forage, orchards, vegetables and oil farming and agriculture. On the other hand, most of seeds. KRB is located in 25-32 to 00-35 northern the rainfall is of the hard and short variety and when latitudes and 00-46 to 00-49 eastern longitudes there is not enough vegetation along the route of the including some parts of Hamedan, Kermanshahan, rainfall, it provokes and leads not only to high flood Lorestan, Ilam, Hamedan, Markazi, Kordestan and water but washes away and carries a large quantity Khuzestan provinces. of water too, some of which precipitate behind the dams, which have been or are being built with colossal amounts of money, leading to the gradual dwindling of their reservoirs. Some examples are the Latian, Sefidrud and Dez dams, which will be filled in a not too distant future. Of the country's 612 plains, about 150 plains are classified as restricted zones under critical conditions, in which, the amount of extracted water is beyond that which they receive. Each year the level of water in these plains declines and in some places even fall by 1.5 meters a year. Currently, under normal circumstances and not during the draught years, we have calculatingly been using 5 billion cu.m of underground waters over the permitted limit. Such further extraction, whether Figure 1- Location map of the Karkheh River Basin illegally or by old permits, occurs in our restricted areas. On the other hand, we have the capacity of Karkheh River has the highest amount of water in increasing underground resources by 5 billion cu.m Iran, after Karoun and Dez Rivers. The water basin in no restricted regions. This means that we have 5 of this river is 42620 square kilometer up to the billion cu.m of over limit water use in restricted bridge and is about 50000 sq. km. up to Hourolazim zones and meanwhile have to the same amount an (swamp), which is its final destination. exploitative water capacity in no restricted areas. The main sub-basins of Karkheh are Gamasiab, Therefore what should be done in our water Gharesou, Saymareh, Kashkan and South Karkheh management system at best is to adjust the negative (as shown in Fig. 2) which themselves include some balance of the restricted zones by a practicable other branches. replacement of the exploitative alternatives of the no restricted regions. Considering the expansion of the basin, the basin divides into 5 sub-basins, which depend on the 2 Karkheh basin rivers located there, themselves divide into under The Karkhe River Basin is located in the middle and sub-basins. southwestern of Zagros Mountain in the west of country. This area is extended about of 50764- 2.2 Hydrographical Network and it is a part of Persian Gulf watershed area. This The general slope of the land and the direction of area is bounded; on north by Sirvan, Ghazel-Ouzan water flow in KRB is from north to south. KR is and Ghare Chay rivers area , on the west by frontier formed from the joint of two main branches called rivers area of Iran and Iraq , on the east by Dez river Gamasiab and Saymareh, which initiated by several , on the south by part of western frontier of country . sub-branches from northeastern and north western of the basin, respectively. They join to each other at 2.1 Location and Area the end of Kermansha plain (10 km from southeastern of Bakhtaran). From here it is called Karkheh River Basin (KRB) is located in the Saymareh and it joins with a river called kashkan western Iran and represents semi-arid and arid areas of the region (Figure 1). The total area of KRB is (another main branch of the western parts of the basin) at a junction and after this junction it is called ISBN: 978-960-474-148-9 115 ISSN: 1790-5095 PROCEEDINGS OF THE 3RD INTERNATIONAL CONFERENCE ON ENERGY AND DEVELOPMENT - ENVIRONMENT - BIOMEDICINE Karkheh. Hydrographical network of the basin is springs with their sub-branches measurement and shown in Figure 2. from Sarabe Gamasiab springs with measurement After Kashkan and Saymareh attachment, KR goes from Sangesourakh station. toward southeast and then after receiving the two It should be mentioned that water resources of sub-branches called Molab and Abzolal, changes its Ravansar springs come from the combined way to south. In Khuzestan plain, the slopes resources of left and right Taghe-Bostan springs. reduction make a change in river bed as Miandar The discharges of these springs are changes from and depend on the rate of speed reduction, cross some 10 liters to few cubic meters in different section and width of the river increase. From where months and years. Water resources of Gamasiab Saymareh and Kashkan join it to Hamidiyeh springs are determined using data from deviational dam, the river length is 250 km, then it Sangesourakh station, which is installed in changes its direction to west and northwest. After its Gamasiab River.