Computer modelling of groundwater overexploitation: case study from the plain of Sidi Bel Abbès (northwestern Algeria)

Abstract

In the plain of Sidi Bel Abbès, the Plio-Quaternary aquifer is the most important groundwater reservoir. Its computer modelling shows that it resembles a toboggan, formed by a succession of connected underground pools. The simulation conducted between 1971 and 2014 reproduced well the average water-table drop of about 11m across the entire aquifer, emphasizing its clear overexploitation, resulting mainly from withdrawals increase parallel to considerable precipitation diminution, especially between 1982 and 2006. The prediction phase simulated between 2015 and 2030 translated significant aquifer drawdowns, especially for scenarios 2 and 3, particularly East and South of the plain. The computer modelling of the aquifer illustrated its continual destocking and reflected its dangerous overexploitation, which if maintained at this rate, could have devastating consequences (complete drying of boreholes,
subsidence, water and soil salinization, etc) on the plain of Sidi Bel Abbès.