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Exploitation of Groundwater Resources
In Yemen and Sudan, eight (013-YA, 060-YD, 068-YD, 156-YD, 202-YD, 228-YD, 253-YD, 046-YD) and three projects (134-SU, 155-SU, 181-SU) respectively, sought to improve supplies of potable or irrigation water from underground sources. While the sustainability of groundwater resources varied, it is evident that current rates of abstraction, particularly in many areas of Yemen, are not sustainable. Thus projects need to exercise extreme care before promoting interventions involving the harvesting of groundwater.
Enormous expansions in the number of wells have occurred in Yemen. Estimates indicate that water levels in the main aquifers are receding at between one and seven metres annually. Declining watertables, aside from necessitating the deepening of wells, an expensive process, create conditions of uncertainty and scarcity as well as increasing the risk of salt intrusion.
In Sudan, one project (134-SU) has contributed to the proliferation of wells (mataras) both in the Nile flood plain areas and the slightly elevated land (upper terrace) adjoining the flood plains. While it is unlikely that mataras near the Nile will, as such, harm the agricultural land in their vicinity, the sustainability of mataras in some high terrace areas is questionable. Problems with salinity have occurred in some matara areas and substantial drops in groundwater levels have been noted in others. The longer term effects on underground water reserves utilised by the wateryards (155-SU, 181-SU) is unclear.
The injection of capital aimed at increasing supplies of underground water for irrigation or domestic consumption, by projects is potentially harmful unless it is based on reliable hydro-geological data and the relevant authorities have the capability to effectively monitor and police groundwater exploitation.
The availability of reliable hydro-geological data should be mandatory before project support to exploitation of groundwater resources is considered.
In some situations, the over-exploitation of groundwater requires immediate and decisive action. Projects should support authorities (both national and regional) in addressing the issues of water resources scarcity, the question of traditional water rights and equity and competition for water between different users. In this context, where regulatory authorities are inadequate, projects should support government in strengthening them.
In addition to regulatory measures, projects should consider support for the design and implementation of master plans for the development of groundwater resources and the rationalization of their exploitation.
As water resources are scarce in some areas, support for more efficient irrigation techniques is a sensible inclusion in future developments.
References:
1. Sudan - Country Portfolio Evaluation, CPE94 CESSU94E IFAD 1992.
2. Sudan - Northern Province Irrigation Rehabilitation Project, SRS 005-SU, Interim Evaluation, 1991.
3. Sudan - Northern Region Agricultural Rehabilitation Project, 134-SU R134SUBE,Interim Evaluation, 1991.
4. Sudan - Stock Route, 155-SU, IFAD, 1984.
5. Sudan - Western Savannah Project - phase II, 181-SU R181SUAE,Mid Term Evaluation, 1988.
6. Yemen - Country Portfolio Evaluation, CPE92 CESYE92E IFAD 1992.
7. Yemen, A.R. - Tihama Development III (Wadi Mawr), 013-YA, IFAD, 1979
8. Yemen, A.R. - Southern Uplands Rural Development Phase II, 046-YA, IFAD, 1980
9. Yemen, A.R. - Central Highlands Agricultural Development, 156-YA, IFAD, 1984
10. Yemen, A.R. - Southern Regional Agricultural Development, 202-YA, IFAD, 1987
11. Yemen, A.R. - Agricultural Credit, 253-YE, IFAD, 1989
12. Yemen, P.D.R. - Agricultural Support Services Project, 060-YD, Mid Term Evaluation, 1984.
13. Yemen, P.D.R. - Cooperative Development of Rainfed Agriculture, 068-YD, IFAD, 1981
14. Yemen, P.D.R. - Eastern Regional Agricultural Development, 228-YD, IFAD, 1988
