Cache Valley Principal Aquifer Storage and Recovery State Assessment: Phase I, Cache Valley, Cache County, Utah, USA

Aquifer storage and recovery (ASR) is the artificial recharge of water into an aquifer, where it is stored for later withdrawal. Artificial recharge is generally achieved either by ponding water in surface basins, where it can seep into the soil and infiltrate into the aquifer (surface spreading), or by injecting the water directly into the aquifer through a well (injection) (Bouwer, 2002). Aquifer storage and recovery allows for the storage of water in the subsurface, while preventing losses from evaporation that occur with surface reservoirs. Using ASR projects in Cache Valley may provide water planners and managers with increased flexibility in managing groundwater resources. A clay confining layer above the principal aquifer, coupled with the distribution of the Salt Lake Formation, a less transmissive formation, limits potential surface-spreading sites to a narrow band along the eastern mountain front of Cache Valley between Green Canyon and Millville Canyon. We identified two potential surface-spreading sites within this target area, one near the mouth of Green Canyon in North Logan, and one east of Providence. Both sites are gravel pits on private property. Since injection wells can penetrate clay layers to reach the aquifer, potential injection sites are limited only by the lateral extent of the principal aquifer, which is roughly a triangle between Smithfield, Wellsville, and Hyrum. We identified an unused well near River Park Drive in the Island area of Logan that penetrates the principal aquifer and would be suitable for use as an injection well. Logan City currently owns the well. Injection of water using the River Park well is an advantageous recharge method over the surface-spreading sites. The principal advantages of this injection well are (1) the sediments underlying the surface-spreading sites are uncertain and would require drilling exploration wells to verify the absence of the clay confining layer or other strata that would prevent water from infiltrating into the principal aquifer, whereas the injection well is completed within the target aquifer zone; (2) the well has already been drilled and has been constructed in a manner that will allow injecting water; and (3) aquifer tests have been conducted on the well and consequently, the hydrogeologic properties surrounding the well are known.