Lakes / Oregon / Polk County / Aaron Mercer Reservoir
Aaron Mercer Reservoir, Oregon
55 acres
Surface Area
Where It Sits, and How Deep It Goes
Locator - Oregon
44.90 degrees N, 123.48 degrees W - Polk 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 Aaron Mercer Reservoir Stacks Up
- Larger than 39% of the 642 lakes counted in Oregon.
- The largest lake in Polk County among those counted.
- About 22 miles from Salem, as the crow flies.
Lakes Nearby
| Lake | County | Distance | Surface Area |
|---|---|---|---|
| Morgan Lake | Polk | 12 mi | 50 acres |
| Lillie Walker Irrigation Pond | Polk | 15 mi | 29 acres |
| Willamette Slough | Marion | 21 mi | 55 acres |
| Stone Quarry Lake | Marion | 23 mi | 42 acres |
| Clear Lake | Marion | 24 mi | 37 acres |
| Mission Lake | Marion | 24 mi | 29 acres |
Straight-line distance between lake centers.
Facts and Figures
Waterbody ID{27E0CCE9-DDBC-4067-B74B-8DF5EFC953C1}
CountyPolk
Lake TypeLake
Coordinates44.9049, -123.4784
Questions About Aaron Mercer Reservoir
How Big Is Aaron Mercer Reservoir?
Aaron Mercer Reservoir covers 55 acres in Polk County, Oregon.
What Is the Largest Lake in Polk County?
Aaron Mercer Reservoir is the largest lake in Polk County, at 55 acres.
Largest Lakes in Oregon
| # | Lake | County | Surface Area | Max Depth |
|---|---|---|---|---|
| 1 | Upper Klamath Lake | Klamath | 62,095 acres | - |
| 2 | Lake Umatilla | Morrow | 50,042 acres | - |
| 3 | Lake Abert | Lake | 37,137 acres | - |
| 4 | Summer Lake | Lake | 31,602 acres | - |
| 5 | Harney Lake | Harney | 31,290 acres | - |
All 642 Oregon lakes ranked by surface area
Sources: USGS NHD (The National Map NHD MapServer layer 12) named waterbodies FTYPE 390/436; counties via Census point-in-polygon lake data (ID {27E0CCE9-DDBC-4067-B74B-8DF5EFC953C1}). Verified October 30, 2026.