The impact of aquifer intensive use on groundwater quality

Groundwater quality degradation owing to intensive aquifer exploitation is recorded in many countries. Recognition of the impact of intensive abstraction of aquifers is nearly almost based on hydraulic phenomena. However, subtle changes in the groundwater chemical composition caused by pumping may often be observed before becoming evident from groundwater level decline. Therefore, groundwater quality monitoring and vulnerability assessment should be implemented and targeted on the specific groundwater quality problem caused by intensive aquifer exploitation. Most often, groundwater quality is affected by saltwater intrusion into coastal aquifers, by the downward and upward influx of poor water quality from superposed and underlying aquifers into exploited aquifers or by the discharge of polluted surface water into phreatic aquifers. Presented case studies show the social, ecological and economic consequences of the uncontrolled intensive use of groundwater resources. The holistic concept reflecting a close connection between surface water and groundwater is emphasised in the policy and management of groundwater resource development, protection and quality conservation.