The majority of people living in Idaho’s Wood River Valley rely on groundwater for drinking water and other uses. A scientifically thorough understanding of this valuable resource is helpful for managers of the groundwater. Today, the U.S. Geological Survey and the Idaho Department of Water Resources published a comprehensive groundwater-flow model for the valley’s aquifer system. Funding for the project was provided by the USGS and the Idaho Water Resources Board.
“The new model is a tool for understanding and conjunctively managing the valley’s surface and groundwater resources,” said IDWR Hydrology Section Manager Sean Vincent. “We anticipate that it will be useful for addressing a variety of water resource issues.”
The model can be used for water-rights administration and for resource planning and management. Resource managers can simulate how increased or decreased pumping from the aquifer system or changes in precipitation and climate would affect groundwater levels and area streams. Previous research conducted by the USGS and others has shown that the valley’s groundwater and surface-water resources are highly interconnected.
The model improves on previous modeling efforts by covering the full extent of the valley’s aquifer system to include the northern limit of land development at the outlet of the North Fork Big Wood River. Previously published models represented only the area south of Hailey.
The three-year effort to develop the model involved hydrologists from both the IDWR and the USGS. They incorporated 4,408 field observations spanning 12 years, including 931 stream-aquifer flow exchange estimates and 3,477 groundwater-level measurements. They also included a detailed representation of aquifer recharge from applied irrigation water.
From model planning through development, the scientists held regular meetings with area residents and a technical advisory committee.
“We took special care to construct a defensible and reproducible model using free, publicly available software,” said USGS hydrologist Jason Fisher. “Anyone can run, copy, distribute, study and change the model. Our goal is to make it easier to continually improve the model as new data are collected.”