Lakes / Idaho / Washington County / Brownlee Reservoir
Brownlee Reservoir, Idaho
12,535.1 acres
Surface Area
Where It Sits, and How Deep It Goes
Locator - Idaho
44.58 degrees N, 117.11 degrees W - Washington 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 Brownlee Reservoir Stacks Up
- Ranks #9 for surface area among the Idaho lakes counted so far - 12,535.1 acres.
- The largest lake in Washington County among those counted.
- About 80 miles from Boise, as the crow flies.
Lakes Nearby
| Lake | County | Distance | Surface Area |
|---|---|---|---|
| Fairchild Reservoir | Washington | 12 mi | 96.62 acres |
| Mann Creek Reservoir | Washington | 16 mi | 230.3 acres |
| Barton Reservoir | Washington | 20 mi | 56.09 acres |
| Hornet Reservoir | Washington | 24 mi | 31.52 acres |
| Little Crane Creek Reservoir | Washington | 26 mi | 35.58 acres |
| Buttermilk Slough | Washington | 29 mi | 59.8 acres |
Straight-line distance between lake centers.
Facts and Figures
Questions About Brownlee Reservoir
How Big Is Brownlee Reservoir?
Brownlee Reservoir covers 12,535.1 acres in Washington County, Idaho.
What Is the Largest Lake in Washington County?
Brownlee Reservoir is the largest lake in Washington County, at 12,535.1 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 127034637). Verified October 30, 2026.