WASHINGTON RESERVOIR REPORT

Last Updated: January 28, 2026

In Washington State, observations of dam and reservoir levels are essential for monitoring water resources. Data indicates that some reservoirs are currently experiencing abnormal conditions. For instance, Wynoochee Lake near Grisdale is slightly below its average level, sitting at 774 feet compared to the average 776.34 feet. Mud Mountain Lake near Buckley is notably lower, as its current level is 908 feet against an average of 931.51 feet. Howard A. Hanson Reservoir near Palmer is also below average, measured at 1081 feet compared to the usual 1125 feet. These discrepancies could be linked to a combination of factors, including regional weather patterns affecting snowpack and river flows, which influence reservoir levels.

Further analysis reveals that while some reservoirs like Chester Morse Lake at Cedar Falls and South Fork Tolt Reservoir near Carnation are close to average levels, others like Lake Tapps near Sumner and Baker Lake at Upper Baker Dam near Concrete are below their typical measurements for this time of year. Franklin Roosevelt Lake at Grand Coulee Dam, however, is over its average at 1284 feet, higher than the 1275.62 feet expected. These abnormal conditions may be attributed to "exceedingly grim" drought forecasts and shifting weather patterns, as reported by regional news sources. Such conditions have the potential to impact water supplies, as well as infrastructure and ecosystems. Missing data for Lake Scanewa and Castle Lake prevents analysis of their conditions. Overall, the variability in reservoir levels across Washington highlights the complex interplay of environmental factors and underscores the importance of continual monitoring and adaptive water management strategies.

Washington state has over 700 dams and reservoirs, many of which provide hydroelectric power and irrigation for agriculture. The Columbia River is the largest source of water for the state, with many major reservoirs located along its length. These include Grand Coulee, Banks Lake, and Lake Roosevelt. The Yakima River basin also has several important reservoirs, including Cle Elum Lake, Kachess Lake, and Bumping Lake. Snowpack in the Cascades and Olympics is critical for water supply, particularly for irrigation during the dry summer months. In recent years, drought conditions have affected much of the state, with record low snowpack levels in 2015 leading to restrictions on water use. Seasonal trends generally see peak water levels in the spring as snowmelt increases streamflow, followed by a gradual decline throughout the summer and fall. Overall, the hydrology of Washington is complex, with a mix of natural and human factors affecting the availability and use of water resources.

Washington state has over 700 dams and reservoirs, many of which provide hydroelectric power and irrigation for agriculture. The Columbia River is the largest source of water for the state, with many major reservoirs located along its length. These include Grand Coulee, Banks Lake, and Lake Roosevelt. The Yakima River basin also has several important reservoirs, including Cle Elum Lake, Kachess Lake, and Bumping Lake. Snowpack in the Cascades and Olympics is critical for water supply, particularly for irrigation during the dry summer months. In recent years, drought conditions have affected much of the state, with record low snowpack levels in 2015 leading to restrictions on water use. Seasonal trends generally see peak water levels in the spring as snowmelt increases streamflow, followed by a gradual decline throughout the summer and fall. Overall, the hydrology of Washington is complex, with a mix of natural and human factors affecting the availability and use of water resources.