Reclaimed Wastewater Storage in Ground‐water Basins

In the absence of an alternative means of wastewater disposal, wastewater reclamation projects involving the use of reclaimed water for irrigation require facilities for seasonally storing the reclaimed water. Surface reservoirs represent one means of providing this seasonal storage. Constructing surface reservoirs, though, can be economically prohibitive. A second option for reclaimed water seasonal storage is the use of ground‐water aquifers. Regulatory restrictions and public health concerns are significant constraints to the recharge of treated wastewater into domestically used ground‐water aquifers. Where basins not subject to these constraints are available, however, ground‐water aquifers offer the potential for providing an economical means of seasonally storing reclaimed wastewater. An example reclaimed water irrigation project in southern California is presented for which the use of a small, isolated ground‐water basin for seasonally storing reclaimed water has been approved. For this southern California project, the use of a ground‐water basin for storing reclaimed water during times of minimal irrigation demand is resulting in a significant reduction in the overall capital costs of required wastewater reclamation facilities.