In the context of European Water Framework Directive (2000/60/CE), EU member countries are recently putting their efforts in improving the quality of water resources in order to enhance its durable consumption, the environmental protection and to improve water ecosystem state. This case regards a historical chloride contamination which affects drinkable groundwater, in a Belgian hydrogeological context. A hydraulic system consisting of pumping wells was implemented to contain the contaminant source; the water collected by this system is discharged into a river nearby, which constitutes an important water way for commerce and tourism for the entire region. The discharge is submitted to some regulatory conditions by regional Authorities: water ecosystem state should not be altered in the respect of some quality parameters. In order to attain quality parameters, in agreement with regional Authorities, a management plan was developed, involving model implementations and several field experiences. The whole studied area is extended to about 200 km². This study constitutes a complex case of water resource management, regarding groundwater and surface water, two environmental contexts that are closely related. Solutions given could be extended to other different cases of responsible and sustainable water resource management projects.