Newest reservoirs in Montana
The year that a reservoir was first filled to the reservoir’s normal elevation – or the year that a natural lake was first dammed – is the determining factor in the age of the body of water. A large reservoir can take more than a year to fill after its dam is first closed. You can find many of the the world’s newest reservoirs on LakeLubbers in the comparison table below. Many of the world’s oldest reservoirs appear on the last page of that list. Note: For some lakes, the completion year data is unknown, so you may see fewer lakes than the total 30 articles we have published for Montana lakes.Thinking about booking a Montana lake vacation home rental, cabin or hotel?
Use our free interactive vacation rental map to search and compare multiple vacation properties at a glance. Enter a lake name, a state or city and then simply click on a listing to compare all similar properties, best rates and availability for your dates.Search results: Sort lakes by completion year
Below are lakes within USA > US West Region > Montana > Compared by newest (youngest) reservoirs and the year it was completed. This list does not represent all lakes in Montana, only the 30 Montana lake articles we have published on the LakeLubbers website.
Lake name  |
Completion year |
Lake description |
|---|---|---|
| Lake Koocanusa, MT / Canada (British Columbia, Canada, Canada, Glacier Country, MT, Montana, US West Region, USA) |
1973 | Also known as Koocanusa Lake, Koocanusa Reservoir In the far north of the United States, tucked into the northwestern end of Montana, is the long, narrow Lake Koocanusa. This lake is actually a man-ma… |
| Canyon Ferry Lake, MT (Gold West Country, MT, Montana, US West Region, USA) |
1955 | For lake lovers who relish the beauty of nature and the wonder of wildlife, there’s no better place to relax and have fun than at Canyon Ferry Lake. A… |
| Hungry Horse Reservoir (Glacier Country, MT, Montana, US West Region, USA) |
1954 | Hungry Horse Reservoir in Montana’s Glacier Country offers a wealth of recreational opportunities to northwestern Montana visitors. The nearly 24,000-… |
| Fort Peck Lake, MT (Missouri River Country, MT, Montana, US West Region, USA) |
1940 | Fort Peck Lake, located 20 miles southeast of Glasgow, Montana on Montana Highway 24, is the 5th-largest man-made reservoir by volume in the United St… |
| Mystic Lake (Montana, US West Region, USA, Yellowstone Country, MT) |
1925 | One of the prettiest lakes in Montana’s Yellowstone Country is Mystic Lake. This beautiful lake sits at 7,637 feet above sea level in the Absaroka-Bea… |
| Hebgen Lake (Gold West Country, MT, Montana, US West Region, USA, Yellowstone Country, MT) |
1914 | Anglers will find some of Montana’s best stillwater trout fishing at Hebgen Lake. The 12,500-acre reservoir lies conveniently just outside the western… |
| Ennis Lake (Gold West Country, MT, Montana, US West Region, USA) |
1906 | In 1905 the Montana Power Company built a dam on the Madison River, creating Ennis Lake. The two and a half mile long lake stretches across Montana’s… |