ABSTRACT
By using field tests, Watermaatschappij Zuid-Holland Oost (WZHO) investigated the possibility of recharging pretreated water from the Rhine, in deep sand layers in the adjacent polder area. The study focused on well clogging and the effects of aquifer passage on the quality of the recharged water. The purpose was to obtain information for the design of a deep well recharge system in practice, and for the sizing of pre-and posttreatment. This paper describes the tests and results from July 1996 to March 1998. The conclusion is that deep well recharge of pretreated Rhine water in the polder area is very promising indeed. Pretreatment of water from the Rhine with rapid sand filtration, coagulation and filtration over activated carbon is needed however, to obtain water with a negligible clogging potential and satisfying EU-regulations. Posttreatment could be as simple as aeration followed by a single rapid sand filtration.
