Lakes / California / Marin County / Nicasio Reservoir
Nicasio Reservoir, California
677 acres
Surface Area
Where It Sits, and How Deep It Goes
Locator - California
38.08 degrees N, 122.74 degrees W - Marin 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 Nicasio Reservoir Stacks Up
- Larger than 85% of the 1,147 lakes counted in California.
- The largest lake in Marin County among those counted.
- About 27 miles from San Francisco, as the crow flies.
Lakes Nearby
| Lake | County | Distance | Surface Area |
|---|---|---|---|
| Soulajule Reservoir | Marin | 5.2 mi | 166 acres |
| Stafford Lake | Marin | 5.6 mi | 105 acres |
| Kent Lake | Marin | 7.3 mi | 459 acres |
| Laguna Lake | Marin | 9.1 mi | 173 acres |
| Alpine Lake | Marin | 11 mi | 200 acres |
| Bon Tempe Lake | Marin | 11 mi | 121 acres |
Straight-line distance between lake centers.
Facts and Figures
Waterbody ID{6411FDC2-D0DC-4638-973B-B50CEBCE0C46}
CountyMarin
Lake TypeLake
Coordinates38.0813, -122.7361
Questions About Nicasio Reservoir
How Big Is Nicasio Reservoir?
Nicasio Reservoir covers 677 acres in Marin County, California.
What Is the Largest Lake in Marin County?
Nicasio Reservoir is the largest lake in Marin County, at 677 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 {6411FDC2-D0DC-4638-973B-B50CEBCE0C46}). Verified October 30, 2026.