Climate Change Impacts on Western Reservoir Operations: A Case Study of Bull Run Watershed, Portland, Oregon

Climate change has the potential to alter the quantity and timing of runoff, which may pose significant challenges for the reservoir management. This study evaluates the projected climate impact on the reservoir system of Portland, Oregon. Using sixteen climate models spanning four emission scenarios, the performance reservoir operating policies and their sensitivity to the choice of GCMs and time periods are assessed. Use of historical rule curves for reservoir operations results reduces forecast reliability for future periods. This general trend for decreasing forecast reliability for future periods is not sensitive to the choice of GCM. Regardless of the selected reservoir policy model, the results suggest a similar range of reliability (62%- 74%), implying that there is no optimal model for the operation of the reservoir