Much interest has centred on the development of the fossil water resources at Kufrah in the central Sahara of Libya. The remote location and extremely arid climate presented unusual problems to irrigation engineers, agriculturists and stock specialists. The favourable estimates made by consultants indicated that the high quality of the water together with the larger quantities available would easily support 10,000 hectares of irrigated alfalfa for steep breeding and the groundwater resource would only be drawn down by 35 metres after 40 years of pumping (Tipton and Kalmbach — 1971). This optimistic phase was at its height in 1973 when the political leadership of the country was pressing the managers of the Kufrah scheme to envisage not just 10,000 hectares of irrigated cropping, but extensions to 50,000 hectares, preferably including settlement schemes.

In the event, however, faced with the decision of how far to extend the scheme, those responsible approved designs for the limited expansion of the project in the form of a 5500 hectare settlement scheme accommodating about 850 farmers. This sharp reduction in the target area for irrigated farming at Kufrah arose because of the results of the first effective year of operation of the scheme, results of which became available during late 1973 and early 1974. The most important indicator of the long term viability of the project was of course the drawdown in the level of the groundwater. Uneasy predictions were being circulated as the result of some important work completed by a Libyan hydrologist (Adib 1974) who had applied a different model from that used by Tipton and Kalmbach in their feasibility study. These new predictions proved to be very close to the measured rates of decline after a year of pumping, a year incidentally in which the scheme had worked at only about 70 per cent or less of its anticipated levels of water use for full fodder and livestock production. Instead of declines of a few metres which would in the early years have been consistent with a 35 metres decline over 40 years of pumping, it was discovered that in parts of the well field drawdowns of as much as 15 metres had been recorded after only one year. Critical conclusions were reached by Pallas and Fadel (1974) on the basis of these data, especially regarding the risks involved in investing heavily on the basis of contested assumptions concerning an aquifer, and they urged that important groundwater developments should be preceded by at least two years of pilot experimentation.