Lakes / Idaho / Elmore County / Big Trinity Lake
Big Trinity Lake, Idaho
25.95 acres
Surface Area
Where It Sits, and How Deep It Goes
Locator - Idaho
43.62 degrees N, 115.43 degrees W - Elmore 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 Big Trinity Lake Stacks Up
- Larger than 2% of the 316 lakes counted in Idaho.
- About 39 miles from Boise, as the crow flies.
Lakes Nearby
| Lake | County | Distance | Surface Area |
|---|---|---|---|
| Anderson Ranch Reservoir | Elmore | 15 mi | 4,515.55 acres |
| Little Camas Reservoir | Elmore | 20 mi | 1,048.34 acres |
| Arrowrock Reservoir | Elmore | 21 mi | 2,287.75 acres |
| Long Tom Reservoir | Elmore | 24 mi | 100.89 acres |
| Cow Creek Reservoir | Elmore | 26 mi | 44.23 acres |
| Lucky Peak Lake | Ada | 29 mi | 2,761.51 acres |
Straight-line distance between lake centers.
Facts and Figures
Questions About Big Trinity Lake
How Big Is Big Trinity Lake?
Big Trinity Lake covers 25.95 acres in Elmore County, Idaho.
What Is the Largest Lake in Elmore County?
Anderson Ranch Reservoir is the largest lake in Elmore County, at 4,515.55 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 55021735). Verified October 30, 2026.