Lakes / Montana / Nelson Reservoir
Nelson Reservoir, Phillips County, Montana
4,115 acres
Surface Area
2,217.28 ft
Surface Elevation
Where It Sits, and How Deep It Goes
Locator - Montana
48.50 degrees N, 107.56 degrees W - Phillips 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 Nelson Reservoir Stacks Up
- The largest lake in Phillips County among those counted.
- About 184 miles from Great Falls, as the crow flies.
- 23 fish species on the FWP list for this lake.
Fish Species
Bigmouth BuffaloBlack CrappieBluegillBurbotChannel CatfishCommon CarpEmerald ShinerFathead MinnowGoldeyeLake ChubLake WhitefishLongnose DaceLongnose SuckerNorthern PikeRiver CarpsuckerShorthead RedhorseSmallmouth BassSmallmouth BuffaloSpottail ShinerStonecatWalleyeWhite SuckerYellow Perch
Species recorded for this lake. Presence only - no abundance ratings.
Facts and Figures
Waterbody ID137854390
CountyPhillips
Coordinates48.4988, -107.5649
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 137854390). Verified October 30, 2026.