Lakes / Idaho / Caribou County / Blackfoot Reservoir
Blackfoot Reservoir, Idaho
16,913.5 acres
Surface Area
Where It Sits, and How Deep It Goes
Locator - Idaho
42.91 degrees N, 111.61 degrees W - Caribou County. State and county outlines drawn from Census boundary data; the lake marker is placed by its USGS National Hydrography Dataset coordinates, not by eye. Schematic - not a survey map.
How Blackfoot Reservoir Stacks Up
- Ranks #6 for surface area among the Idaho lakes counted so far - 16,913.5 acres.
- The largest lake in Caribou County among those counted.
- About 45 miles from Idaho Falls, as the crow flies.
Lakes Nearby
| Lake | County | Distance | Surface Area |
|---|---|---|---|
| Hole in the Rock | Caribou | 5.7 mi | 146.29 acres |
| Little Valley Reservoir | Bonneville | 13 mi | 166.29 acres |
| Twentyfour Mile Reservoir | Caribou | 14 mi | 37.31 acres |
| Grays Lake | Bonneville | 17 mi | 337.33 acres |
| Chesterfield Reservoir | Caribou | 18 mi | 1,264.44 acres |
| Alexander Reservoir | Caribou | 18 mi | 1,007.26 acres |
Straight-line distance between lake centers.
Facts and Figures
Questions About Blackfoot Reservoir
How Big Is Blackfoot Reservoir?
Blackfoot Reservoir covers 16,913.5 acres in Caribou County, Idaho.
What Is the Largest Lake in Caribou County?
Blackfoot Reservoir is the largest lake in Caribou County, at 16,913.5 acres.
Largest Lakes in Idaho
| # | Lake | County | Surface Area | Max Depth |
|---|---|---|---|---|
| 1 | Lake Pend Oreille | Bonner | 92,764.44 acres | - |
| 2 | American Falls Reservoir | Power | 55,319.78 acres | - |
| 3 | Coeur d'Alene Lake | Kootenai | 26,891.64 acres | - |
| 4 | Lake Cascade | Valley | 25,043.4 acres | - |
| 5 | Priest Lake | Bonner | 23,425.59 acres | - |
All 316 Idaho lakes ranked by surface area
Sources: USGS National Hydrography Dataset (The National Map) lake data (ID 55438848). Verified October 30, 2026.