ABSTRACT
The Snowmelt Runoff Model (SRM) was used to simulate timing and magnitude of runoff for six climate scenarios (2030 and 2080 ‘Wet’, ‘Middle’, and ‘Dry’). The water supply results from SRM were run through a Southern Idaho reservoir operation and water rights allocation model (MODSIM). The 2030-Dry and 2080-Dry scenarios produce supply deficits relative to the current climate of 5.4%, and 1.9%, respectively, for which the corresponding irrigation water delivery reductions were 1.7% and 2.7%. In contrast, the 2030-Wet, 2030-Mid, 2080-Wet, and 2080-Mid climate change scenarios increased water supply by 13.4%, 0.5%, 19.5%, and 5%, respectively, for which water deliveries increased by 0.41%, 0.04%, 0.34% and 0.14%, respectively. Idaho’s irrigation delivery and storage system can ameliorate the risk of dry climate change, but is incapable of storing and delivering the increased water supplied by the wet climate change scenarios. This is an opportunity worth exploring.
