Glacier-fed Diablo Lake
Seattle City Light recently funded a study which researched and forecasted the recession patterns of glaciers in our region. The research article, titled “Glacier Recession and the Response of Summer Streamflow in the Pacific Northwest United States, 1960-2099,” explores the recent recession patterns of these glaciers whose melt and water flow will impact hydroelectric power generation, agricultural water supply, and the ecological health of the watersheds downstream. Along with funding a portion of the research, City Light advised on the scope of the project to provide insight into when streamflows were most important for power generation, recreation, and fish protection.
Through hydrological modeling, the study found that primarily temperature-induced shrinking of glaciers will increase throughout this century. The model showed that the glaciers in the North Cascades could nearly disappear by the year 2100 if greenhouse gas emissions are not curbed.
For Ronda Strauch, City Light’s climate change adaptation researcher and adviser, this research is vital to not only the health of the glaciers but shapes how utilities that generate power with hydroelectricity like City Light will continue their operations in the future.
“We look to research like this for future predictions of inflows into the reservoirs and how much hydroelectric power our utility will be able to produce,” explains Strauch. “We wanted to make sure that glacier activity was added to this hydrologic model used in this research to get a better picture of streamflow into our reservoirs. It could also guide our operational changes in the future, such as controlling water levels to reserve for the summer months. This will help us decipher the long-term consequences of these melting glaciers.”
One of the consequences is the potential lowering water levels along the Skagit River during late summer. In keeping with City Light’s commitment to environmental stewardship, such as supporting the salmon recovery plan that protects and restores the chinook, bull trout and other species listed under the Endangered Species Act in the Skagit Watershed, the utility is watching closely this kind of research to better understand the changes in climate the region will incur for decades to come.
“The future still has a lot of uncertainty to it,” said Strauch. “While it is not completely set, there are some aspects of the future that is clear. It’s our job as a utility to do what we can to ensure that future generations are prepared for the impacts. Our decisions help prepare for what the future will look like.”