Once irrigated and lush but now barren, the Mesopotamian plain circling the ruins of Gilgamesh’s Uruk makes present day calls for food security via vast new irrigation projects appear shortsighted. Irrigation today suffers the same problems as in ancient times — salt buildup in the soil, collapsing dams, irrigation channels narrowed and blocked by silt buildup — plus some new ones, such as pesticide runoff. But irrigation planners figure they have learned a few things since Gilgamesh’s time. We can expect Egypt, Iraq, Saudi Arabia and others to go on building new, expensive irrigation projects until they finally reach the limits of their water supplies. Reaching these limits should take only two or three more decades.
Irrigation development dangles too great a promise as a technical solution to meeting food needs. Transforming deserts into something green and fertile is a powerful vision. Irrigation covers only a fraction of the total cropped land (Table I), but irrigated output per acre is much higher than rainfed.  Except for a few places such as North Yemen, Middle Eastern rainfed lands are semi-arid, planted mainly in wheat and barley. Middle East rainfed yields for wheat are as little as one-fourth those possible with irrigation. And with irrigation, two or more crops may be reaped per year.
By reusing agricultural drainage and urban wastewater flows, and by exploiting yet untapped surface and groundwater, Middle Eastern countries can increase their irrigated areas by at least 50 percent over the next two decades.  Egypt and Iraq, with their major river systems, account for over half the total. Vast Sudan bears even more raw potential, but its irrigation dreams will stay on hold until well into the next century.
The most basic obstacle is that few states enjoy unfettered sovereignty over their water resources. Even Bahrain, an island, shares its aquifer with Saudi Arabia, and must worry about overpumping on the mainland. Water conflicts have contributed to, if not instigated, broader tensions between Israel and its neighbors (over the Jordan River), and Iraq and Syria (the Euphrates), to mention only the best known examples.  Nile politics have long shaped relations between Egypt and Sudan. Continued irrigation development may induce new water-sharing agreements between the region’s co-riparians. More likely, countries will build redundant, poorly located but sovereign dams, and develop irrigation competitively rather than cooperatively, hoping to establish “prior use” water claims. 
Mobilizing investment sums of $1,000-$5,000 per hectare is the next hurdle countries must surmount to achieve their irrigation goals. Rough estimates are that Sudan could add a whopping 2.5 million hectares irrigated and 20 million hectares rainfed to its cropped area; but the cost is well beyond the present bankrupt government. Iraq proposes to increase its irrigated area from the present 1.75 million hectares to about 3 million. Poorer Egypt has a long-stated goal of adding 1.5 million hectares to its present 2.5 million. It now hopes to finance this mainly by private capital and outside donors. Saudi Arabia and the richer Gulf states will keep indulging in expensive irrigation projects; but their cash is not matched by very much potential or large numbers of mouths to feed. New projects in North Africa should be smaller scale, with the grandiose exception of Libya’s $25 billion, 180,000 hectare Great Manmade River scheme. 
Against the political allure of large-scale irrigation projects, studies in Egypt and elsewhere have shown that returns look much higher to rehabilitating existing irrigation systems and promoting technical change among smaller farmers.  If Egypt had to choose between investing in its old lands or building new projects, it would be better off betting on the old.
That does not mean Egypt and Iraq should forego new lands projects. Middle East countries aim to be fully using ground and surface water still available within the next 20-30 years. The issue is making new projects succeed, not whether to do them at all. Egypt, and now Iraq as Baghdad sprawls, have to keep reclaiming some land just to keep up with losses to urban use.  Conflicts in Egypt over new lands versus old are really a symptom of too low a rate of investment in the agricultural sector as a whole. 
Key to making crops grow on poorer desert soils are modern drip and sprinkle irrigation technologies. They are more expensive than surface irrigation (though marginally so for new projects), and more complex. These methods are more water efficient compared to conventional surface methods.  New irrigation methods can have a positive interaction with established agricultural areas, rather than merely competing with them for resources, if modern irrigation technology spreads from the new areas to the old. It might seem implausible to imagine Egyptian fellahin, whose present irrigation methods echo those of the Pharaohs, doing this kind of “high tech” farming; but their role models can be found right now in Jordan, where drip and sprinkle irrigation have proven compatible with smallholder agriculture.
 Worldwide, irrigation now covers 20 percent of the harvested land, but receives 60 percent of all fertilizer, and produces 40 percent of all crops. IBRD, World Development Report 1981-82 (Baltimore: Johns Hopkins Press, 1982).
 Inefficient surface irrigation, with water delivered to the fields by leaky earthen canals, is the rule in most of the Middle East. Canal lining and converting to water-efficient drip and sprinkle irrigation methods can increase water use efficiency (i.e., the portion of water used that the crop actually transpires) from the present 40 percent or less to 80 percent or higher. For an overview on irrigation efficiency, see E.G. Kruse and D.F. Heermann, “Implications of Irrigation System Efficiencies,” Soil and Water Conservation, November/December 1977. For a review of water resources in the Middle East, see C.E. Gischler, Water Resources in the Arab Middle East and North Africa (Wisbech, UK: Middle East and North African Studies Press, 1979).
 T. Naff and R.C. Matson, eds., Water in the Middle East: Cooperation or Conflict? (Boulder, CO: Westview Press, 1984).
 Regarding dams, the Aswan Dam was only one of several of Egypt’s options for gaining control of the Nile; probably not even the best one. But foremost, it would be on Egyptian soil. J. Waterbury, Hydropolitics of the Nile Valley (Syracuse: Syracuse University Press, 1979).
 For more on Libya’s Great Manmade River scheme see: Middle East Economic Digest, December 9, 1983, pp. 25-28; September 7, 1984, pp. 10-11; July 20, 1985, pp. 14-16; and February 8, 1986, p. 22.
 See K.W. Easter, ed., Irrigation Investment, Technology, and Management Strategies for Development (Boulder, CO: Westview Press, 1985).
 Official estimates in the late 1970s were that 40-60,000 feddans per year of agricultural land were being converted to other use. If correct, this would amount to about one percent of the land base per year. The problem is especially critical in the overcrowded Nile Delta. National Urban Policy Study, Egypt: Urban Growth and Urban Data Report (Cairo: Prepared by PADCO Inc. for the Advisory Committee for Reconstruction, Ministry of Development, 1982).
 Agriculture received only 5-10 percent of gross fixed investment in the late 1970s and early 1980s, while its share of gross domestic product was 20 percent. See E.T. York, et.al., Egypt Strategies for Accelerating Agricultural Development (Cairo: Ministry of Agriculture of the Arab Republic of Egypt and the US Agency for International Development. 1982).
 Kruse and Heermann.