Evaluating the Effect of Climate Change on the Design Parameters of Embankment Dams: Case Studies Using Remote Sensing Data

In climate change conditions, warmer temperature accompanied by greater precipitation could lead to the formation of larger snowpack and earlier spring melting of the snowpack, which in turn could increase the magnitude of runoff in a cold region basin. Conversely, lower temperatures accompanied by lesser precipitation could lead to a decrease in runoff within the basin. Both scenarios, along with other climate change scenarios, could alter the basin runoff in a confounding manner and challenge the validity of parameters used in the designs of embankment dams. Spillways, stilling basins, and outlet structures will be impacted most as compared with other appurtenances of the dams. Rivers emptying into reservoirs deposit sediments on the bottom of reservoirs, and the built up over the productive years could decrease the water storage volume. In the scenario with greater precipitation and surface runoff, the frequency of having flooding and overtopping events increases. The above climate change impact factors were investigated for Renwick Dam in North Dakota by having the upper basin areas modeled by HEC-HMS and SWAT. After both models were calibrated, the behaviors of the reservoir during the future time periods were simulated using downscaled climate change data as the inputs. The results provided by both models are compared. There are interesting differences observed. A sensitivity analysis scheme is also used to derive some rational inferences on the uncertainties of the model calibration results and the implications of the design parameters.