Big Lake, located in Missoula, Montana, is a significant earth dam constructed in 1915 primarily for water supply purposes.
Wind
Humidity
The dam stands at a height of 30 feet and has a storage capacity of 621 acre-feet, with a normal storage capacity of 143 acre-feet. The reservoir covers a surface area of 38 acres and drains a 4.1 square mile watershed, with a maximum discharge of 95 cubic feet per second.
Managed by the local government and regulated by the Montana Department of Natural Resources and Conservation (DNRC), Big Lake is classified as having a significant hazard potential and a moderate risk level. The dam features an uncontrolled spillway with a width of 25 feet and outlet gates that are also uncontrolled. The last inspection of the dam was conducted in August 2017, with its condition currently rated as "Not Rated" in terms of assessment.
Water resource and climate enthusiasts will find Big Lake an intriguing structure due to its historical significance, design, and operational details. Situated in a picturesque location in the Seattle District, the dam serves as a vital resource for water supply in the region. With its unique features and regulatory oversight, Big Lake presents an opportunity for further exploration and study in the realm of water resource management and climate resilience.
Year Completed |
1915 |
Dam Length |
440 |
Dam Height |
30 |
River Or Stream |
TR-LAKE CREEK |
Primary Dam Type |
Earth |
Surface Area |
38 |
Hydraulic Height |
18 |
Drainage Area |
4.1 |
Nid Storage |
621 |
Structural Height |
19 |
Outlet Gates |
Uncontrolled |
Hazard Potential |
Significant |
Nid Height |
30 |
South Fork Jocko River Near Arlee Mt
|
83cfs |
Clark Fork Above Missoula Mt
|
1140cfs |
Blackfoot River Near Bonner Mt
|
382cfs |
Clark Fork Below Missoula Mt
|
2310cfs |
Clark Fork At Turah Bridge Nr Bonner Mt
|
718cfs |
Bitterroot River Near Missoula Mt
|
1010cfs |
Wrangle Creek Headwaters, Sec. 18, T15N, R18W To Mainstem, Sec. 21, T15N, R18W
Lake Creek Headwaters, Sec. 30, T15N, R18W To Mainstem, Sec. 21, T15N, R18W
High Falls Creek Headwaters, Sec. 5, T14N, R18W To Mainstem, Sec. 2, T14N, R18W
East Fork Headwaters, Sec. 8, T14N, R17W To Mainstem, Sec. 14, T14N, R18W
Spring Gulch Headwaters, Sec. 12, T14N, R19W To Mainstem, Sec. 35, T14N, R19W
Mainstem Headwaters, Sec. 4, T15N, R18W To Boundary, Sec. 2, T13N, R18W