Climate Change, Fish, Agriculture, and Power: Impacts and Implications for Future Snake River Water Resources Management

This paper describes the approach taken in a study exploring water resources impacts associated with climate change scenarios in the Snake River basin in the Pacific Northwest. The Snake River is an extremely important river within the Columbia River basin that supports significant agricultural activity. Recently, a series of dams on this river have been targeted for removal because of their impact on salmon. Transient climate ensembles are used as inputs to the Variable Infiltration Capacity (VIC) macroscale hydrologic model to predict daily transient streamflow scenarios throughout the basin to 2050. Water resource simulation models are used to predict, on a monthly time-step, the implications of the altered climates on changes in streamflow timing and volume in approximately 91.5 % of the basin’s 17.9 BCM of total storage. Preliminary results from these models indicate that both short and long-term climate change will have important implications for future policy and operational decisions in the region. Of particular interest are the effects of increasingly stringent river outflow regulation on irrigation deliveries, fish endangerment, hydropower generation, and flood control. Early analysis indicates that the predicted changes in magnitude and timing of future streamflows under climate change conditions will impact reliability in these areas. To address these concerns, a series of operational alternatives and optimizations are developed that mitigate future agricultural, economic, hydropower, and environmental impacts on the system