Chapitre 12 : Setting sustainable abstraction limits in confined aquifers: example from deep con-fined aquifers in the Bordeaux region, France
Résumé
This chapter describes the management of the deep aquifers in the Gironde De-partment of south-western France, which supply drinking water to the City of Bor-deaux and almost all the1.5 million inhabitants of the Department from about 400 wells. These deep aquifers are a strategic resource for the Gironde area because of their accessibility and excellent water quality. Already in the 1950s, the risk of over-exploitation of these resources was recognised (Schoeller, 1956), in particular for the Eocene aquifer whose groundwater levels showed a clear decline. The resulting awareness of this risk led to the implementation of specific regulations, before im-plementation of management policies as set down in the Law on Water of 1992. Major investigations were carried out to improve knowledge of the aquifers, moni-tor the groundwater levels, and develop ground-water flow models. The local stake-holders involved in aquifer management employed these modelling tools to create the principles and policies for controlling groundwater-abstraction. The current wa-ter management regime in the Gironde Department is the result of a long scientific and technical policy evolution, which has led to an operating process that supports consultation and regulation within the legal framework of a Water Development and Management Plan (SAGE in French).