Lakes / Montana / Ruby River Reservoir
Ruby River Reservoir, Montana
941 acres
Surface Area
5,389.04 ft
Surface Elevation
Where It Sits, and How Deep It Goes
Locator - Montana
45.22 degrees N, 112.13 degrees W - Madison County. State and county outlines drawn from Census boundary data; the lake marker is placed by its Montana Fish, Wildlife & Parks coordinates, not by eye. Schematic - not a survey map.
How Ruby River Reservoir Stacks Up
- About 61 miles from Bozeman, as the crow flies.
- 9 fish species on the FWP list for this lake.
Fish Species
Arctic GraylingBrook TroutBrown TroutLongnose SuckerMountain WhitefishRainbow TroutWestslope Cutthroat TroutWhite SuckerYellowstone Cutthroat Trout X Westslope Cutth.
Species recorded for this lake. Presence only - no abundance ratings.
Facts and Figures
Waterbody ID51933903
CountyMadison
Coordinates45.2210, -112.1266
Largest Lakes in Montana
| # | Lake | County | Surface Area | Max Depth |
|---|---|---|---|---|
| 1 | Fort Peck Lake | Valley | 233,053 acres | - |
| 2 | Flathead Lake | Lake | 122,132 acres | About 380 ft |
| 3 | Canyon Ferry Lake | Broadwater | 32,773 acres | About 170 ft |
| 4 | Lake Koocanusa | Lincoln | 28,723 acres | - |
| 5 | Hungry Horse Reservoir | Flathead | 23,577 acres | - |
Sources: Montana Fish, Wildlife & Parks lake data (ID 51933903). Verified October 30, 2026.