Lakes / Arizona / Coconino County / Grass Flat Tank
Grass Flat Tank, Arizona
106 acres
Surface Area
Where It Sits, and How Deep It Goes
Locator - Arizona
34.98 degrees N, 111.46 degrees W - Coconino 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 Grass Flat Tank Stacks Up
- Larger than 59% of the 198 lakes counted in Arizona.
- About 18 miles from Flagstaff, as the crow flies.
Lakes Nearby
| Lake | County | Distance | Surface Area |
|---|---|---|---|
| Perry Lake | Coconino | 1.4 mi | 27 acres |
| Mormon Lake | Coconino | 2.7 mi | 4,904 acres |
| Ducksnest Lake | Coconino | 3.7 mi | 63 acres |
| Post Lake | Coconino | 3.7 mi | 59 acres |
| Ashurst Lake | Coconino | 4.4 mi | 180 acres |
| Als Lake | Coconino | 4.6 mi | 28 acres |
Straight-line distance between lake centers.
Facts and Figures
Questions About Grass Flat Tank
How Big Is Grass Flat Tank?
Grass Flat Tank covers 106 acres in Coconino County, Arizona.
What Is the Largest Lake in Coconino County?
Mormon Lake is the largest lake in Coconino County, at 4,904 acres.
Largest Lakes in Arizona
| # | Lake | County | Surface Area | Max Depth |
|---|---|---|---|---|
| 1 | Lake Mohave | Mohave | 27,571 acres | - |
| 2 | Lake Havasu | Mohave | 18,560 acres | - |
| 3 | San Carlos Reservoir | Gila | 13,059 acres | - |
| 4 | Lake Pleasant | Yavapai | 9,186 acres | - |
| 5 | Theodore Roosevelt Lake | Gila | 9,075 acres | - |
All 198 Arizona 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 130877292). Verified October 30, 2026.