Agricultural threats to groundwater. The Egyptian situation
1998
Attia, F.A.R. (National Water Research Center, Kanater (Egypt). Research Institute for Groundwater)
Groundwater is gaining increasing importance in the National water policy of Egypt due to the limited surface water available from the Nile. Groundwater is a major source for domestic water supply in the Nile Valley and Delta, being the only source of water in the Egyptian deserts. The total area under irrigation in Egypt amounts about 30,240 km2, 95 per cent of which is confined to the Nile Valley and Delta. The Nile Delta itself encompasses 63 per cent of the irrigated area. The major threats to groundwater from agriculture in areas irrigated with fresh water include: (i) large drawdowns and increasing salinity where groundwater is the major irrigation source; (ii) increased concentration of nitrogen, and pesticide residues, especially at shallow depths; and (iii) inland movement of the sea water wedge due to extensive groundwater withdrawals for irrigation. On the other hand, in sewage-based irrigated areas, pathogenic pollution is pronounced. Groundwater protection has recently become a National policy. The National programs related to groundwater protection include: (i) regional and problem specific monitoring of the resource; (ii) preparation of hydrogeological, vulnerability and groundwater potential maps; (iii) development of legislation with respect to the use of groundwater and agricultural chemicals; (iv) undertaking research programs and studies related to groundwater environmental management and protection; and (v) conduction of public awareness programs.
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