| Abstract: | This paper studies the effect of drought and pumping discharge on groundwater supplies and marine intrusion. The investigation concerns the Mamora coastal aquifer, northwest of Morocco. A large‐scale groundwater model was established to model (a) the amount of freshwater discharge towards the ocean and the sea water volumes flowing inland as a consequence of the inverse hydraulic gradient, (b) the impact of drought and pumping discharge on the water table level and, as a consequence, on marine water intrusion. In fact, the simulated submarine groundwater discharge (SGWD) would decrease from 864 m3/d/km in 1987 to 425 m3/d/km in 2000. The simulated volumes of sea water intruding the aquifer as a result of inverse hydraulic gradient would increase from 0·25 Mm3/y in 1987 to 0·3 Mm3/y in 2000. As a consequence of a negative rainfall gradient of ?5 mm/y, the simulated SGWD would decline to 9 m3/d/km and the sea water intrusion (SWI) would increase to 0·35 Mm3/y since the year 2010. Due to insufficient data on the trend of pumping discharge, a hypothetical increase of this latter from 38·3 Mm3/y to 53·2 Mm3/y is simulated to induce an increase of marine water intrusion from 0·25 Mm3/y to 0·9 Mm3/y. Consequently, to optimally exploit this seemingly fragile coastal aquifer, a plan of future actions to implement is proposed. Copyright © 2005 John Wiley & Sons, Ltd. |
