ABSTRACT
For the past twenty years, the town of Atlantis in the Western Cape has used artificial recharge to augment local groundwater supplies. Stormwater and high quality treated domestic wastewater are infiltrated into the primary aquifer, up gradient of a production wellfield used for potable supply. The attenuation capacity for infiltrated solutes is limited because of the thin unsaturated zone and low clay content of the silica sand aquifer. This means that recharge water quality has had to be managed, by separating sources of different salinity and nutrient content. The Atlantis scheme faces several water quality management challenges, ranging from the control of saline water encroachment to industrial pollution threats and biofouling of production boreholes. The success of the recharge scheme relies on hydrochemical monitoring and the ensuing adaptation of recharge practices to protect the quality of the groundwater resource.
