MONTANA RESERVOIR REPORT

Last Updated: January 22, 2026

Montana hosts a number of significant dams and reservoirs critical for water supply, irrigation, flood control, and recreation. Among these, Flathead Lake at Polson, MT, is one of the largest natural freshwater lakes in the western United States. Recent observations indicate its water surface elevation stands at 2892 feet above datum as of January 22, 2026, which is slightly above the average of 2889.53 feet. This increase suggests a higher-than-normal water level for the time of year, which may be influenced by factors such as precipitation, snowpack conditions upstream, and river inflows. While a slight deviation from the average is not necessarily alarming, it can indicate changing watershed conditions that may need to be monitored for potential impacts on water management and downstream ecosystems.

Current conditions at Flathead Lake contrast with historic data and the broader context of Montana's water systems. The state's reservoirs and their management often reflect the balance between seasonally-driven snowmelt and the demands of agriculture, energy, and residential use. Abnormal conditions in one reservoir could point to broader hydrological changes, such as altered snowpack melt rates due to climate variability or changes in precipitation patterns. Stakeholders, including water managers and local communities, rely on the continuous monitoring of these water bodies to inform decisions and mitigate risks associated with water scarcity or flooding. While the slight elevation in Flathead Lake's water surface could be part of a natural fluctuation, it is essential to validate this data against other sources such as snowpack measurements, river flow data, and climate reports to determine the precise cause and prepare for any necessary actions.

Montana has many reservoirs and dams that provide water for irrigation, hydropower, and recreation. Some notable reservoirs include Fort Peck Lake on the Missouri River, Hungry Horse Reservoir on the Flathead River, and Lake Koocanusa on the Kootenai River. These reservoirs receive water from various streams, rivers, and creeks in the surrounding areas, with snowpack and mountain melt contributing significantly to the water supply. The general hydrology of Montana is influenced by its mountainous terrain, with the western part of the state having a wetter climate and the eastern part being more arid. Record levels have been observed in recent years due to heavy snowfall and precipitation, but the state has also experienced drought conditions in some areas. Seasonal trends show that spring and early summer are the wettest times of the year, while late summer and fall are typically drier. Overall, reservoirs and dams play an important role in managing Montana's water resources and supporting various industries and recreational activities.

Montana has many reservoirs and dams that provide water for irrigation, hydropower, and recreation. Some notable reservoirs include Fort Peck Lake on the Missouri River, Hungry Horse Reservoir on the Flathead River, and Lake Koocanusa on the Kootenai River. These reservoirs receive water from various streams, rivers, and creeks in the surrounding areas, with snowpack and mountain melt contributing significantly to the water supply. The general hydrology of Montana is influenced by its mountainous terrain, with the western part of the state having a wetter climate and the eastern part being more arid. Record levels have been observed in recent years due to heavy snowfall and precipitation, but the state has also experienced drought conditions in some areas. Seasonal trends show that spring and early summer are the wettest times of the year, while late summer and fall are typically drier. Overall, reservoirs and dams play an important role in managing Montana's water resources and supporting various industries and recreational activities.