Geography and Population
Iraq, with a total area of 438,320 square kilometers (km2) including 924 km2 of inland waters, is surrounded by Iran to the east, Turkey to the north, Syria and Jordan to the west, Saudi Arabia and Kuwait to the south, and the Persian Gulf to the south-east. Topographically Iraq is shaped like a basin, consisting of the Great Mesopotamian alluvial plain of the Tigris and the Euphrates rivers. (Mesopotamia means, literally, the land between two rivers). This plain is surrounded by mountains in the north and the east, which can reach altitudes of 3,550 meters (m) above sea level, and by desert areas in the south and west, which account for over 40% of the land area. For administrative purposes, the country is divided into 18 governorates, of which three are gathered in an autonomous region.
It is estimated that 11.48 million hectares (ha) are cultivable, or 26% of the total area of the country. The total area estimated to be used for agriculture is 8 million ha, which is almost 70% of the cultivable area. However. due to soil salinity, fallow practices and the unstable political situation it is estimated that only 3 to 5 million ha are actually cultivated annually. In 1993, the area actually cultivated was estimated at about 3.73 million ha, of which 3.46 million ha consisted of annual crops and 0.27 million ha consisted of permanent crops.
The total population is about 20.4 million (1995), of which 25% is rural. Average population density is estimated at 47 inhabitants/km2, but ranges from 5 inhabitants/km2 in the Anwar province, in the desert in the western part of the country, to more than 170 inhabitants/km2 in the Babylon province, in the center of the country. The average population growth was estimated at 3.6% during 1980-90, but emigration of foreign workers and severe economic hardship have reduced this growth rate since 1990. In 1989, the agriculture sector contributed only 5% to gross domestic product (GDP), which was dominated by oil (61%). About 20% of the labor force is engaged in agriculture.
Climate and Water Resources
The climate is mainly of the continental, subtropical semi-arid type, with the north and northeastern mountainous regions having a Mediterranean climate. Rainfall occurs from December to February (or November to April in the mountains) during cool to cold winters, with a day temperature of about 16°C dropping at night to 2°C with a possibility of frost. Summers are dry and hot to extremely hot, with a shade temperature of over 43°C during July and August, yet dropping at night to 26°C.
Rainfall is very seasonal and occurs mainly between December and February, except in the north and north-east of the country where the rainy season is longer, from November to April. Average annual rainfall is estimated at 154 millimeters (mm), but ranges from less than 100 mm over 60% of the country in the south up to 1,200 mm in the north-east.
There is only one river basin in Iraq, the Shatt Al-Arab basin. The Shatt Al-Arab is the river formed by the confluence downstream of the Euphrates and the Tigris and flows into the Persian Gulf after a course of only 190 kilometers (km). Before their confluence, the Euphrates flows for about 1,000 km and the Tigris for about 1,300 km respectively within the Iraqi territory. Nevertheless, due to the importance of the Euphrates and the Tigris, the country is generally divided into three river basins: the Tigris, the Euphrates, and the Shatt Al-Arab (referring to the part downstream of the confluence of the two rivers).
Surface Water Resources
Both the Tigris and the Euphrates are international rivers originating in Turkey. The Tigris river basin in Iraq has a total area of 253,000 km2, or 54% of the total river basin area.
The average annual flow of the Euphrates as it enters Iraq is estimated at 30 cubic kilometers (km3), with a fluctuating annual value ranging from 10 to 40 km3. Unlike the Tigris, the Euphrates receives no tributaries during its passage in Iraq. About 10 km3 per year are drained into the Hawr al Harnmar (a marsh in the south of the country).
- the Greater Zab, which originates in Turkey and is partly regulated by the Bakhma dam. It generates 13.18 km3 at its confluence with the Tigris; 62% of the 25,810 km2 of river basin is in Iraq;
- the Lesser Zab, which originates in Iran and is equipped with the Dokan dam (6.8 km ). The river basin of 21,475 km2 (of which 74% is in Iraqi territory) generates about 7.17 km, of which 5.07 km3 of annual safe yield after the Dokan construction;
- the Al-Adhaim (or Nahr Al Uzaym), which drains about 13,000 km2 entirely in Iraq. It generates about 0.79 km3 at its confluence with the Tigris. It is an intermittent stream subject to flash floods;
- the Diyala, which originates in Iran and drains about 31,896 km2, of which 75% in Iraqi territory. It is equipped with the Darbandikhan dam and generates about 5.74 km3 at its confluence with the Tigris;
- the Nahr at Tib, Dewarege (Doveyrich), and Shehabi rivers, draining together more than 8,000 km2. They originate in Iran, and bring together in the Tigris about 1 km3 of highly saline waters;
- the Al-Karkha, whose course is mainly in Iran and, from a drainage area of 46,000 km2, brings about 6.3 km3 yearly into Iraq, namely into the Hawr Al Hawiza during the flood season, and into the Tigris river during the dry season.
The Karun river, originating in Iran flows with its mean annual flow of 24.7 km3 into the Shatt Al-Arab. It brings a large amount of fresh water into the Shatt Al-Arab, just before it reaches the sea.
The Euphrates and the Tigris are subject to large and possibly disastrous floods. The level of water in the Tigris can rise at the rate of over 30 centimeters per hour (cm/hour). In the southern part of the country, immense areas are regularly inundated, levees often collapse, and villages and roads must be built on high embankments. The Tharthar reservoir was planned inter alia in the 1950s to protect Baghdad from the ravages of the periodic flooding of the Tigris by storing extra water discharge upstream of the Samarra barrage.
In 1980, a Joint Technical Committee on Regional Waters was created by Turkey and Iraq, on the basis of a former protocol (1946) concerning the control and management of the Euphrates and the Tigris. Syria joined the committee afterwards.
The Euphrates represents the most critical issue for Iraq's water strategy as more than 90% of its water comes from outside the country (against only 50% for the Tigris). According to an agreement between Syria and Iraq, Iraq shares the Euphrates' waters with Syria on a 58% (Iraq) and 42% (Syria) basis, based on the flow received by Syria at its border with Turkey. Since Turkey has unilaterally promised to secure a minimum flow of 15.8 km3/year at its border, this agreement would de facto represent 9 km3/year for Iraq. Up to now, there has been no global agreement between the three countries concerning the Euphrates' waters.
Good quality subterranean water has been found in the foothills of the mountains in the northeast of the country and in the area along the right bank of the Euphrates:
- the aquifer in the north-east of the country has an estimated sustainable discharge of between 10 and 40 m3/second, at depths of five to fifty meters. Its salinity increases towards the south-east of the area, where it reaches 1 milligrams (mg)/1;
- the aquifers on the right bank of the Euphrates river are found at depths up to 300 m, and have an estimated discharge of 13 m3/s. Salinity varies between 0.3 and 0.5 mg/l.
In other areas of the country, groundwater is also found, but always with a salinity level higher than 1 mg/l.
In 1977, the on-river dams, all of which are located in the Tigris river basin, had a total capacity of 13.7 km3. There was an important program of dam construction in Iraq in the 1980s. The program consisted of the construction of the Saddam dam on the Tigris (11.1 km3), the Kadisiyya (Qadisia) multipurpose dam on the Euphrates (8.2 km3), the Bakhma dam on the upper Zab, one of the Tigris tributaries (17.1 km3), the Badush dam on the Tigris river (0.5 km3), and several other desert dams totalling about 0.5 km3. The total on-river storage capacities for the Tigris will thus amount to 42 km3, and 8.2 km3 for the Euphrates river, i.e. a total of 50.2 km3. However, the Bakhma dam was completely destroyed. At present, the Al-Adom dam on the Tigris river, with a capacity of 3.8 km, is under construction.
Two off-river storage lakes have been created with the construction of the Tharthar dam (85 km3) in the Tigris river basin, filled with the Wadi Tharthar waters and, since 1985, with Euphrates waters, and the Habbaniya dam (3.3 km3), which can be filled from upstream Euphrates waters and which drains into the Euphrates downstream.
In order to increase water transport efficiency, minimize losses, and waterlogging, and improve water quality, a number of new watercourses were constructed, especially in the southern part of the country. The Saddam river (or Third river) functions as a main out-fall drain collecting drainage waters of more than 1.5 million hectares of agricultural land from north of Baghdad to the Gulf, between the two main rivers (the Euphrates and the Tigris). The length of the watercourse, completed in December 1992, is 565 km, with a total discharge of 210 m3/s. Other watercourses were also constructed to reclaim new lands or to reduce waterlogging.
Total water withdrawal is estimated at 42.8 km3 in 1990, of which 92% is used for for agricultural purposes (3% is used for domestic supplies and 5% for industrial use). According to the most recent estimates, 85% of river water withdrawal is used for agricultural purposes.
In 1991, safe water supplies reached 100% of urban areas but only 54% of rural areas. The situation has deteriorated as a result of the Gulf War as regards the water supply and sanitation sector, due inter alia to shortages in chlorine imports for water treatment.
Irrigation and Drainage Development
The history of irrigation started 7,500 years ago in the land between the Tigris and the Euphrates when the Sumerians built a canal to irrigate wheat and barley.
Irrigation potential was estimated in 1990 at over 5.5 million ha, of which 63% are in the Tigris basin, 35% are in the Euphrates basin, and 2% are in the Shatt Al-Arab basin. Considering the soil resources, it is estimated that about 6 million hectares are classified as excellent, good or moderately suitable for flood irrigation. With the development of water storage facilities, the regulated flow has increased and changed the irrigation potential significantly, since it was estimated at 4.25 million hectares only in 1976. However, irrigation development depends to a large extent on the volume of water released by the upstream countries.
The total water managed area was estimated at 3.5 million ha in 1990, all of it being equipped for full or partial control irrigation.
The areas irrigated by surface water are estimated at 3,305,000 ha, of which 105,000 ha (3%) are in the Shatt Al-Arab river basin, 2,200,000 ha (67%) are in the Tigris river basin, and 1,000,000 ha (30%) are in the Euphrates river basin. However, it should be noted that all these areas are not actually irrigated, since a large part has been abandoned due to waterlogging and salinity. Only 1,936,000 ha were estimated to be actually irrigated in 1993.
The areas irrigated from groundwater were estimated at 220,000 ha in 1990, with some 18,000 wells. About 8,000 ha were reported equipped for micro-irrigation, but these techniques were not used.
Salinity has always been a major issue in this area and it was already recorded as a cause of crop yield reductions some 3,800 years ago.
It is estimated that in 1970 half the irrigated areas in central and southern Iraq were degraded due to waterlogging and salinity. The absence of drainage facilities and, to a lesser extent, the irrigation practices used (flooding) were the major causes of these problems. In 1978, a land rehabilitation program was undertaken, comprising concrete lining for irrigation canals, installation of field drains and collector drains. By 1989, a total of 700,000 ha had been reclaimed at a cost of around $US 2,000/ha.
Recent estimations have nevertheless shown that 4% of the irrigated areas were severely saline, 50% medium saline, and 20% slightly saline, i.e. a total of 74% of the irrigated areas suffered from some degree of salinity. The Ministry of Irrigation estimated at 17 million tons the amount of salt transported to the Gulf by the Saddam river in 1995. Irrigation with highly saline waters (more than 1500 ppm) has been practiced for date palm trees since 1977. The use of brackish groundwater is also reported for tomato irrigation in the south of the country.
In 1991, there were 224,490 ha of irrigated wheat, with an average yield of 2.7 tons/ha, while the rainfed wheat area was estimated at 508,620 ha, with an average yield of 1.7 tons/ha. There were 200,770 ha of irrigated barley, with an average yield of 1.8 tons/ha, while the rainfed barley area was estimated at 323,730 ha, with an average yield of 1.3 tons/ha. The other main irrigated crops are rice, maize, vegetables, but also date trees which are important for the economy of the southern part of the country.
The Ministry of Agriculture is responsible for organizing the ownership of agricultural lands, contracts with farmers, cooperatives, and agricultural companies in addition to enhancing agricultural investment activities. In particular, the Ministry is responsible for providing agricultural inputs to all farmers, and for marketing the agricultural commodities.
The Ministry of Irrigation is in charge of water resources development, irrigation, and drainage development, as well as its operation and maintenance. Its major functions are to assess water requirements and resources, control running water, reservoirs, wetland and marshes, underground water, the construction of dams, canals and drainage systems, soil conservation, classification, land evaluation and use, and research and studies on land and water. The Ministry is executing most of the water resources development projects with the assistance of a number of State companies.
The State Company for Water Wells Drilling (SCWWD) has launched a program of well drilling, mainly for irrigation purposes.
Trends in Water Resources Management
Two main sprinkler irrigation projects were planned in 1990: the Saddam irrigation project, supplied by waters from the Third river, was designed for a total area of 250,000 ha, and the El Jazira irrigation project which should cover an area of 325,000 ha. The Um Almaarik river in the south west region has recently been excavated in order to irrigate 20,000 ha upon completion.
However, the development of irrigation as it is planned in the upstream countries, particularly the South-east Anatolian (GAP) project in Turkey, and the irrigation projects in Syria will reduce Iraqi irrigation potential unless an agreement is reached on the sharing of waters between the riparian countries. Since water shortages are forecast to occur with the development of irrigation, solutions have to be found for an integrated basin-level planning of water resources development.
Another main issue in water resources management is protection of water quality. The level of salinity in the Euphrates river is high and is expected to increase with the development of irrigation in the basin and, as a consequence, the diminution of the water flow, particularly in the dry' season.
Treatment of municipal and industrial wastewater is considered as one way to preserve river water quality. Reuse of treated wastewater for irrigation was also envisaged before 1990. Some industries are already obliged to desalinate the Euphrates waters before using it.
Other measures which could be undertaken would need regional cooperation, for a better management of the flood waters and the dams. But the regulation capacities on the Euphrates river are already greater than the entire average flow, because of the lack of coordination between the riparian countries.
- Water profile of Iraq, Food and Agriculture Organization.
- World Factbook: Iraq, Central Intelligence Agency.
- Badry M. M., Mehdi M. S. and Khawar J. M., 1979. Water resources in Iraq. In: Irrigation and agricultural development, a joint publication of ECWA, FAO and the Foundation for Scientific Research of Iraq, edited by S.S. Johl. Pergamon Press.
- ECWA. FAO. 1984. Agricultural resources management and desertification control in Iraq. Report EIECWAIAGR/83/8. Baghdad, Iraq.
- ESCWA. 1992. Water resources database in the ECSWA region. Report E/ECSWA/ENR/1992/6.
- FAO. 1994. Country information brief, Iraq. FAO-Representation in Iraq.
- Fisher W. 1994. Iraq: Physical and social geography in the Middle East and North Africa". Europe publications limited.
- UNDTCD. 1990. Progress in the implementation of the Mar del Plata Action plan in the region of Near east and North Africa. Report prepared by Minther J. Haddadin. Amman, Jordan.
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