Survival, transport and dissemination of Escherichia coli and enterococci in a fissured environment. Study of a flood in a karstic aquifer.

In fissured aquifers, hydrodynamic phenomena combined with a network of permeable fissures imparts varying degrees of vulnerability depending on the type of contaminant. The study presented here examines the impact on a karst aquifer of a river which receives effluents from a sewage treatment plant just upstream from the point of recharge. This recharge constitutes a source of bacteriological and chemical pollution.