Lakes / Wyoming / Johnson County / Purdy Reservoir
Purdy Reservoir, Wyoming
42.5 acres
Surface Area
Where It Sits, and How Deep It Goes
Locator - Wyoming
44.02 degrees N, 106.66 degrees W - Johnson County. State and county outlines drawn from Census boundary data; the lake marker is placed by its Wyoming Game and Fish Department coordinates, not by eye. Schematic - not a survey map.
How Purdy Reservoir Stacks Up
- Larger than 45% of the 783 lakes counted in Wyoming.
- About 83 miles from Casper, as the crow flies.
Lakes Nearby
| Lake | County | Distance | Surface Area |
|---|---|---|---|
| Pole Creek Irrigation Reservoir | Johnson | 4.0 mi | 27.92 acres |
| Willow Glen Reservoir | Johnson | 5.1 mi | 25.88 acres |
| Baker Number 1 Reservoir | Johnson | 5.8 mi | 53.75 acres |
| Horn Creek Reservoir | Johnson | 6.7 mi | 32.63 acres |
| Muddy Guard Reservoir Number 2 | Johnson | 12 mi | 36.55 acres |
| Pass Reservoir | Johnson | 18 mi | 27.18 acres |
Straight-line distance between lake centers.
Facts and Figures
Questions About Purdy Reservoir
How Big Is Purdy Reservoir?
Purdy Reservoir covers 42.5 acres in Johnson County, Wyoming.
What Is the Largest Lake in Johnson County?
Lake De Smet is the largest lake in Johnson County, at 3,331.88 acres.
Deepest Natural Lakes in Wyoming
| # | Lake | County | Surface Area | Max Depth |
|---|---|---|---|---|
| 1 | Deep Lake | Park | 285 acres | 472 ft |
| 2 | Lake Reno | Park | 107 acres | 222 ft |
| 3 | Snowdrift Lake | Teton | 57 acres | 174 ft |
| 4 | Crater Lake | Big Horn | 39 acres | 166 ft |
| 5 | Beauty Lake | Park | 94 acres | 165 ft |
All 120 Wyoming lakes ranked by depth
Largest Lakes in Wyoming
| # | Lake | County | Surface Area | Max Depth |
|---|---|---|---|---|
| 1 | Yellowstone Lake | Teton | 84,442 acres | - |
| 2 | Flaming Gorge Reservoir | Sweetwater | 38,888.36 acres | 440 ft |
| 3 | Jackson Lake | Teton | 26,853.22 acres | - |
| 4 | Pathfinder Reservoir | Carbon | 22,000 acres | 192 ft |
| 5 | Seminoe Reservoir | Carbon | 20,000 acres | 200 ft |
All 783 Wyoming lakes ranked by surface area
Sources: USGS National Hydrography Dataset (The National Map) lake data (ID 75346815). Verified October 30, 2026.