Title: Development of a Hydrologic Model to Explore Impacts of Climate Change on Water Resources in the Big Wood Basin, Idaho

of annual precipitation comes in the form of winter snowfall, water supplies may be particularly sensitive to a warming climate. We worked with a network of stakeholders in the Big Wood Basin, Idaho, to explore how climate change may affect water resources and identify strategies that may help mitigate the impacts. The 8,300 square kilometer region in central Idaho contains a mixture of public and private land ownership, a diversity of landcover ranging from steep forested headwaters to expansive desert shrublands to a concentrated area of urban development that has experienced a quadrupling of population since the 1970s. With nearly 60 % of precipitation falling as winter snow, stakeholders expressed concern regarding the vulnerability of the quantity and timing of seasonal snowpack as well as surface water supplies used primarily for agricultural irrigation under projected climate change. Here, we achieve two objectives. The first is the development of a hydrologic model to represent the dynamics of the surface water system in the Big Wood Basin. We use the semi-distributed model Envision-Flow to represent surface water hydrology