USGS Grant Number:
Year Established: 2011 Start Date: 2011-09-01 End Date: 2013-08-31
Total Federal Funds: $177,336 Total Non-Federal Funds: $178,610
Principal Investigators: Gaisheng Liu, Andrea Brookfield, James Butler, Marios Sophocleous, Donald Whittemore, Andrew Ziegler
Abstract: Aquifer storage and recovery (ASR) is the artificial recharge and temporary storage of water in an aquifer during times when water is abundant, and recovery of all or a portion of the water during times when it is needed. In recent years, interest in ASR has increased due to various concerns such as declining groundwater resources, vulnerability of surface water supplies to contamination and reservoir sedimentation, and unfavorable projections of future climate change. Currently, many limiting factors still hinder the effectiveness of ASR as a new tool for water resources management. One of the major technical challenges has been how to design artificial recharge systems that can efficiently transfer source water into the aquifer. Typically aquifer recharge is achieved through various surface infiltration methods (such as basins and trenches) and/or large-diameter (greater than 40 cm) injection wells. Surface infiltration methods are only applicable for near-surface aquifers when subsurface soils are permeable and adequate land is available at reasonable cost. Large-diameter injection wells are equipped with high-power pumps so that water can be forcefully injected into the aquifer at a high rate. They are expensive, as they require a high level of logistical and infrastructure support for pump operation and maintenance. This proposed research is directed at developing a new artificial recharge method for near-surface aquifers using small-diameter, low-cost wells installed with direct-push (DP) technology. Unlike the large-diameter injection wells, the DP wells are typically small in diameter (less than 10 cm), low in construction and maintenance costs, and limited to depths less than 30 m. Water is allowed to move through the wells by gravity, so the required logistical and infrastructure support are modest. The DP wells can potentially be combined with surface methods to enhance the rate of aquifer recharge, which will shorten the residence time of water in basins/trenches and reduce the evaporative water loss of surface methods. On the other hand, when surface infiltration methods are not applicable due to the low permeability of near-surface materials, the DP wells can penetrate through the low-permeability materials and be screened in the more permeable zones. The DP wells, if proven practically useful as a supplemental or alternative recharge option to surface methods, could be utilized by water-resources managers to significantly increase the effectiveness of ASR in near-surface aquifers. In this project, numerical modeling will be combined with field recharge tests to rigorously investigate the utility of DP wells for artificially recharging near-surface aquifers. Field recharge tests will be conducted at a site in the Lower Republican River basin of north-central Kansas, and a small-scale infiltration basin, trench, and fourteen to eighteen 5.1 cm-diameter DP wells will be constructed. The results of this project are expected to be of significant interest to water resources managers throughout the United States and around the world, as ASR is increasingly utilized as one of the most practical approaches to combat future water-supply challenges. To maximize the impact of this project, the results of this work will be widely disseminated through presentations, reports, publications, short courses, webinars, public information circulars, and web-based products.