Lakes / California / Tuolumne County / Rock Island Lake
Rock Island Lake, California
40 acres
Surface Area
Where It Sits, and How Deep It Goes
Locator - California
38.07 degrees N, 119.47 degrees W - Tuolumne 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 Rock Island Lake Stacks Up
- Larger than 23% of the 1,147 lakes counted in California.
- About 94 miles from Fresno, as the crow flies.
Lakes Nearby
| Lake | County | Distance | Surface Area |
|---|---|---|---|
| Peeler Lake | Tuolumne | 3.2 mi | 72 acres |
| Smedberg Lake | Tuolumne | 4.2 mi | 43 acres |
| Benson Lake | Tuolumne | 5.1 mi | 176 acres |
| Rodgers Lake | Tuolumne | 5.6 mi | 44 acres |
| Spiller Lake | Tuolumne | 5.9 mi | 27 acres |
| Mary Lake | Tuolumne | 6.8 mi | 66 acres |
Straight-line distance between lake centers.
Facts and Figures
Questions About Rock Island Lake
How Big Is Rock Island Lake?
Rock Island Lake covers 40 acres in Tuolumne County, California.
What Is the Largest Lake in Tuolumne County?
Don Pedro Reservoir is the largest lake in Tuolumne County, at 10,980 acres.
Largest Lakes in California
| # | Lake | County | Surface Area | Max Depth |
|---|---|---|---|---|
| 1 | Salton Sea | Imperial | 233,096 acres | - |
| 2 | Lake Tahoe | Placer | 122,975 acres | - |
| 3 | Goose Lake | Modoc | 93,048 acres | - |
| 4 | Honey Lake | Lassen | 59,917 acres | - |
| 5 | Mono Lake | Mono | 45,124 acres | - |
All 1,147 California 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 66758847). Verified October 30, 2026.