Approaches for Assessing Groundwater Availability Under Competing Demands and Climate Change
Abstract
The Yakima River Basin in eastern Washington, like many areas of the arid American West, struggles with issues of water allocation. The 1 billion dollar agricultural economy in the basin lowlands is one of the largest in the United States and is principally based on the diversion of about 6,000 ft3/s of surface water. The mountainous uplands generate the snowmelt runoff for irrigation and fish habitat, making riverine transport of surface water of paramount importance. Surface water in the basin is fully appropriated in average years and over-appropriated in dry years, but there are increasing demands for water for municipal, fisheries, agricultural, industrial, and recreational uses. These demands must be met through the use of groundwater, increased storage, greater conservation, and or purchasing water rights. In some areas, groundwater pumping has caused water level declines of more than 300 ft, potentially reducing streamflow in reaches with senior surface-water rights or instream flow requirements for endangered species. A variety of analytic tools have been developed to address the issues of water management under existing conditions, future growth scenarios, and potential regional climate change, including a comprehensive assessment of groundwater. The hydrologic and hydrogeologic framework that has been developed is integrated into an overlapping series of groundwater models. The models have been designed to evaluate 1) surface water impacts from existing pumpage and potential new pumpage, 2) effects of projected changes in climate on groundwater use, 3) potential improvements in irrigation efficiencies on water availability, 4) artificial recharge and aquifer storage systems, and 5) the relative utility of various aquifer management strategies. In combination, these approaches may lead to a way to accommodate municipal, agricultural and ecological needs of the basin within the physical limitations of the hydrologic system.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2008
- Bibcode:
- 2008AGUFM.H13G1015B
- Keywords:
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- 1807 Climate impacts;
- 1829 Groundwater hydrology;
- 1830 Groundwater/surface water interaction;
- 1831 Groundwater quality;
- 1880 Water management (6334)