Seawater problem in the alluvial coastal aquifer of Nador, Tipaza, Algeria

Abstract

This work focuses to the study of the coastal aquifer of Tipaza in the north of Algeria, for highlights mechanisms of potential seawater intrusion into groundwater. Tipaza aquifer has been overexploited for irrigation and water supply, which caused a negatively impacts on its water quality. To investigate these impacts, many tools have been carried out as: monitoring of piezometric level and physico-chemical analysis of 24 wells from 2008 to 2012 and pumping tests. The piezometric map shows the existence of zero meter level inside the plain; which making this area vulnerable to seawater intrusion, where isovalue curves of some chemical parameters are in increasing towards the sea. Results show also a high concentration gradient of some parameters in the first two kilometers, at 1 mS.cm-1.km-1 for EC and 600 to 900 mg.L-1.km-1 for sodium and chlorides respectively. The hydrochemical study confirmed the hypothesis of seawater intrusion in the coastal aquifer of Nador.