WISCONSIN RESERVOIR REPORT

Last Updated: December 24, 2025

In Wisconsin, a state renowned for its picturesque lakes and waterways, the latest reservoir and dam observations indicate that water levels in several major water bodies are experiencing lower than average gage heights for this time of year. Typically, Wisconsin's snowmelts and seasonal rains replenish these water sources, maintaining their levels within a standard range. However, as of December 24, 2025, prominent lakes such as Lake Winnebago, Lac Vieux Desert, Devils Lake, Lake Mendota, Lake Monona, and Lake Waubesa are reporting gage heights below their averages, suggesting potential concerns for water management and local ecosystems. Lake Winnebago, for instance, has observed a decrease to 2 feet in gage height at Oshkosh and near Stockbridge, from its average of 2.61 and 2.57 feet, respectively. This indicates a trend of lower water levels that may affect local water supplies and recreational activities.

Delving into details, Lac Vieux Desert near Land O'Lakes also shows a slight drop from its average of 80.11 feet to a current 80 feet. More conspicuously, Devils Lake near Baraboo has fallen from an average of 8.13 feet to just 7 feet, and Lake Mendota at Madison is down from an average of 9.8 feet to 8 feet, both of which could hint at potential impacts on wildlife habitats and boating conditions. Similarly, Lake Monona at Madison and Lake Waubesa at McFarland are experiencing declines to 4 feet and 3 feet from their respective averages of 5.12 feet and 4.94 feet. These abnormal conditions may be related to lower than average snowpacks or diminished river flows, which typically feed these reservoirs. This trend could have implications for water resource management, requiring vigilant monitoring and potentially adaptive measures to mitigate any negative effects on water supply, flood control, and environmental health. While cross-referencing with additional data sources is necessary for a comprehensive analysis, these preliminary observations highlight the importance of ongoing monitoring and assessment in the face of changing environmental conditions.

Wisconsin has multiple reservoirs and dams that play a crucial role in providing water for irrigation, hydroelectric power generation, and recreational activities. The major reservoirs and dams in the state include Lake Winnebago, Lake Wisconsin, Castle Rock Lake, and Petenwell Lake. These reservoirs are fed by several rivers and creeks, such as the Wisconsin River, Fox River, Rock River, and Black River. The hydrology in the area is influenced by the snowpack in the northern mountains, particularly during the spring and summer months when snowmelt contributes to the streamflow. In recent years, Wisconsin has experienced both record high and low water levels due to changing climate patterns and extreme weather events. In 2021, drought conditions in the state led to lower than average water levels in some reservoirs and creeks. However, seasonal trends also play a role in water levels, with typically higher levels in the spring and early summer months. Overall, reservoirs and dams remain an important component of the state's water infrastructure, and their management is critical in ensuring sustainable water use and management.

Wisconsin has multiple reservoirs and dams that play a crucial role in providing water for irrigation, hydroelectric power generation, and recreational activities. The major reservoirs and dams in the state include Lake Winnebago, Lake Wisconsin, Castle Rock Lake, and Petenwell Lake. These reservoirs are fed by several rivers and creeks, such as the Wisconsin River, Fox River, Rock River, and Black River. The hydrology in the area is influenced by the snowpack in the northern mountains, particularly during the spring and summer months when snowmelt contributes to the streamflow.

In recent years, Wisconsin has experienced both record high and low water levels due to changing climate patterns and extreme weather events. In 2021, drought conditions in the state led to lower than average water levels in some reservoirs and creeks. However, seasonal trends also play a role in water levels, with typically higher levels in the spring and early summer months. Overall, reservoirs and dams remain an important component of the state's water infrastructure, and their management is critical in ensuring sustainable water use and management.