Managed Underground Storage of Recoverable Water System: A Tool for Sustainable Development of Regional Water Resources

Managed underground storage (MUS) of recoverable water system is a tool for securing water supplies for sustainable development of a community.  A MUS system refers to the purposeful recharge of water into an aquifer system for intended recovery and use as component of long-term water resource management.  It has been used to augment municipal water supplies, sustain agricultural production, and enhance ecosystem restoration around world.  In this paper, the authors assess opportunity and challenges in development of a MUS system.  A MUS system usually includes following major components: sources water, recharge method, storage space, recovery approach and uses of the recovered water.  The intended uses of recovered water are controlling factors in design and operation of a MUS system.  The authors use the El Paso Reclamation Water Recharge System as an example to demonstrate components of a MUS system and discuss issues faced during design and operations of the system.  The initial intention of this project is to replenish the depleted aquifer and reuse the reclaimed water.  The recovered water will be used for municipal water supplies, which is required to meet safe drinking water standard.  The source water is the reclaimed water through tertiary treatment. Recharge facilities include recharge wells and one infiltration basin.  The recharged water is stored in the Hueco Bolson aquifer for at least two years as required by regulations.  The stored water is eventually recovered by neighboring production wells for municipal supplies.  The hydrological processes of water recharge through wells and the infiltration basin were analyzed in detail using numerical models. Challenges faced in design and during operation of the system were discussed, including hydrological conditions, residence time requirement, water quality compatibility as well as economic considerations.