Some of the Largest and Oldest of the World's Irrigation Systems Have

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Some of the largest and oldest of the semi-arid regions of the Middle has a volume 17 times greater than the world’s irrigation systems have East and Africa. that of the Cheops pyramid) has caused waterlogging and leaching out Salination of land is the latest and cumulated almost every conceivable of salts from the soil. Studies covering perhaps the most severe side effect of side-effect in addition to the water- a period of 4,000 years (from 2600 one of the world’s largest water logging and salination of irrigated BC to AD 1400) of written records management undertakings, the High areas, which started manifesting itself in Mesopotamia indicate that such dam at Aswan and related develop- in the Nubaraya region, some 50 “side effects” are recurrent. Salinity ments. This year the dam is a major kilometers south-west of Alexandria. surveys were started there in about subject of public debate, and the When the Nubaraya irrigation proj- 2400 BC but nevertheless, the history target of a parliamentary investigation ect was initiated, a study of under- of the region is punctuated by the ordered by Sayed Marei, president of ground water tables was envisaged, rising of saline waters to plant root the National Assembly (who headed but it was not considered as urgent, level. Many historians believe that the World Food Conference in Rome since most aquifers were at depths of agricultural catastrophes, rather than last November). between 20 and 60 m&es. A network wars, invasions, or climatic changes, The Aswan dam has been the sub- of canals was dug and the water was have precipitated the fall of some of ject of violent criticism, some of it pumped step by step to a few metres the first great civilizations in the ignoring a major achievement: the (and occasionally as high as a few “fertile crescent.” In India likewise, Nile valley farmer is no longer sub- tens of m&es) above sea-level, to be 4,000 year-old surface salt traces, jected to the sometimes deadly vaga- distributed through secondary canals. signifying similar agricultural decline ries of the river. Year-round irrigation The desert started growing green over and fall, have been found. permits the growing of three or four an area of some 200,000 hectares, It may seem surprising that the crops a year on land where only one about 40 percent of all new land problem has not been solved by had been possible in the wake of the whose reclamation had been made modern science. In the 1950s and annual flooding of the past. The dam possible by the High dam. Cultures 6Os, thousands of hectares of irrigated stands in the way of disastrous floods, included one-third fodder (chiefly land in India were lost to salination. and provides water in periods of alfalfa), one-third fruit, and one- And today, Egypt faces the same drought. This was illustrated two third field crops and vegetables. situation, whose solution is essential years ago, when the natural flow of When, a few years ago, some trees not only to meet the agricultural needs the Nile was the lowest in about 100 and grape vines in limited areas of the country, but to the successful started dying, inadequate use of fer- carrying out of vast irrigation sche- Nevertheless, it is true that this tilizer was first suspected. But it soon mes, now underway or projected, in pharaonic project (masonry at Aswan became evident that abundant irriga-

Sick canal: intensive research Abandoned canal: the short-term is underway. solution. 11

tion had made water tables rise at a phic growth, can make the difference the inflow through the turbines. fantastic rate, sometimes exceeding between subsistance agriculture and The potential of the project, to be one centimetre a day, or four metres sufficiency, Egypt may be a key con- developed over 20 years, is enormous. a year. Saline groundwater percolated tributor to hydrological science, par- Floating platforms could be used to to the surface, overflowing into main ticularly concerning its applications drill for oil believed to exist under irrigation canals, some of which had in semi-arid tropics and on sandy soils. the depression (at present the oil is to be abandoned, and even threatening The High dam experience may of difficult access because of salty nearby low-lying fertile land in the have something to do with Egypt’s swamps on the surface). Petro- Nile delta that had been cultivated cautious approach to another spec- chemical industries would be created, for thousands of years. tacular project, the flooding with sea and part of the electrical power Now hundreds of hectares have to water of the Qattara depression in generated would be used for water be put out of cultivation every year the Western desert, a development desalination to cultivate the desert. and many farmers, complaining that that could produce five times as much Oil would be exported to Europe “the harvest burns,” leave the land electricity as the Aswan dam, and through the canal and the new har- that had been allocated them. lead to the creation of agricultural bow. The canal could also be used No long-term solution has yet been and industrial centres and a large for fishery and aquaculture, and a found. Drainage canals would have harbour near El Alamein, the site of network of roads would be built for to be so deep that their cost is pro- a crucial World War II battle. the area. hibitive, and digging wells to pump The project was, in fact, first sug- The Federal Republic of Germany underground water out to sea is, like- gested by Friedrich Bassler, a hydrau- has contributed funds for a prelim- wise, too costly. Short term solutions lic engineer and professor at Darm- inary study, and work on the Qattara include less abundant irrigation, con- stadt University, who was a young project could theoretically start in two stant monitoring of salinity, and officer in Rommel’s Africa Corps years. But the Ministry of Power has closing some of the canals. during World War II. In 1941 he had decided to form a council of experts, Intensive research is underway to made a cursory inspection of the both Egyptian and foreign, to study find an answer, and also methods to depression while studying various not only the technical, economic and foresee and prevent such potentially possible routes for the German army, social aspects of the project, but its catastrophic situations. But in many and he has returned to the site several possible side effects. These could also respects, the Aswan dam’s side effects times since. be spectacular. Evaporation combined point to the fact that water science, The depression starts about 70 with the constant inflow of sea water or hydrology, has remained largely kilometers south of El Alamein, would increase salt concentration to empirical, and has not benefited from curves west and then south for some turn the lake into a “dead sea”; salt sufficient research. 300 kilometers and, at its deepest water under pressure might leak, (The year 1975 brings to a dis- point, reaches 133 meters below sea through geological faults or fissures, appointing close the uluesco-sponsored level. to nearby agricultural areas; or else “Hydrological decade”; as is pointed The Qattara project involves the make existing water tables rise, either out in a recent FAO report (Man’s digging of a 40 kilometer-long canal to feed fresh water artesian wells, or Influence on the Hydrological Cycle) from the Mediterranean to the nor- provoke a salination effect similar to “resources being devoted [to it1 are thernmost tip of the depression. that occurring in the irrigated areas sadly inadequate, and in spite of the Water rushing from the sea would west of the Nile delta. efforts being made, progress is dis- generate electricity, and eventually There are many faces to a water appointingly small. The lack of fun- create a 14,000 square kilometer management project, and Egypt is in damental information on the part of artificial lake. Water would then a good position to realize the interest high-level decision-makers is often evaporate at a rate compensating for of knowing all of them. quite incredible.“) The decision of Egypt’s political leaders to open the High dam debate appears as a significant step toward unprejudiced understanding of a proj- ect that, sooner or later, had to be carried out (unless one took the posi- tion that because of the magnitude of the task, nothing should be yen- tured, nothing risked, but nothing gained either). Now a holistic ap- proach has been taken whereby agricultural, chemical, biological, geo- logical, hydrological and other con- sequences of the dam, as well as its social and public health implications, will be studied and integrated on computer models. As a technically and scientifically advanced developing country, and also one where good water manage- ment, in the face of rapid demogra- Fresh water on one side, (1 brackish lagoon on rhe other