Lakes / California / Sonoma County / Lake Ilsanjo
Lake Ilsanjo, California
32 acres
Surface Area
Where It Sits, and How Deep It Goes
Locator - California
38.43 degrees N, 122.63 degrees W - Sonoma 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 Lake Ilsanjo Stacks Up
- Larger than 13% of the 1,147 lakes counted in California.
- About 47 miles from San Francisco, as the crow flies.
Lakes Nearby
| Lake | County | Distance | Surface Area |
|---|---|---|---|
| Santa Rosa Creek Reservoir | Sonoma | 2.2 mi | 59 acres |
| Bell Canyon Reservoir | Napa | 12 mi | 74 acres |
| Lake Hennessey | Napa | 15 mi | 763 acres |
| Rector Reservoir | Napa | 16 mi | 81 acres |
| Laguna Lake | Marin | 16 mi | 173 acres |
| Weeks Lake | Napa | 20 mi | 124 acres |
Straight-line distance between lake centers.
Facts and Figures
Questions About Lake Ilsanjo
How Big Is Lake Ilsanjo?
Lake Ilsanjo covers 32 acres in Sonoma County, California.
What Is the Largest Lake in Sonoma County?
Lake Sonoma is the largest lake in Sonoma County, at 2,235 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 109413665). Verified October 30, 2026.