Lakes / Colorado / Boulder County / Marshall Lake
Marshall Lake, Colorado
220 acres
Surface Area
Where It Sits, and How Deep It Goes
Locator - Colorado
39.95 degrees N, 105.21 degrees W - Boulder 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 Marshall Lake Stacks Up
- Larger than 82% of the 778 lakes counted in Colorado.
- About 6 miles from Boulder, as the crow flies.
Lakes Nearby
| Lake | County | Distance | Surface Area |
|---|---|---|---|
| Base Line Reservoir | Boulder | 3.5 mi | 261 acres |
| Harper Lake | Boulder | 3.5 mi | 27 acres |
| Great Western Reservoir | Jefferson | 4.7 mi | 142 acres |
| Rocky Flats Lake | Jefferson | 5.2 mi | 43 acres |
| Leggett and Hillcrest Reservoir | Boulder | 5.5 mi | 507 acres |
| Waneka Reservoir | Boulder | 6.3 mi | 48 acres |
Straight-line distance between lake centers.
Facts and Figures
Questions About Marshall Lake
How Big Is Marshall Lake?
Marshall Lake covers 220 acres in Boulder County, Colorado.
What Is the Largest Lake in Boulder County?
Boulder Reservoir is the largest lake in Boulder County, at 536 acres.
Largest Lakes in Colorado
| # | Lake | County | Surface Area | Max Depth |
|---|---|---|---|---|
| 1 | John Martin Reservoir | Bent | 11,686 acres | - |
| 2 | Blue Mesa Reservoir | Gunnison | 8,944 acres | - |
| 3 | Lake Granby | Grand | 7,075 acres | - |
| 4 | Lake Meredith | Crowley | 5,539 acres | - |
| 5 | Adobe Creek Reservoir | Bent | 4,770 acres | - |
All 778 Colorado 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 128059043). Verified October 30, 2026.