Lakes / California / Los Angeles County / San Dimas Reservoir
San Dimas Reservoir, California
35 acres
Surface Area
Where It Sits, and How Deep It Goes
Locator - California
34.16 degrees N, 117.77 degrees W - Los Angeles 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 San Dimas Reservoir Stacks Up
- Larger than 18% of the 1,147 lakes counted in California.
- About 28 miles from Los Angeles, as the crow flies.
Lakes Nearby
| Lake | County | Distance | Surface Area |
|---|---|---|---|
| Puddingstone Reservoir | Los Angeles | 5.3 mi | 248 acres |
| Morris Reservoir | Los Angeles | 5.9 mi | 284 acres |
| San Gabriel Reservoir | Los Angeles | 6.3 mi | 525 acres |
| Arnold Reservoir | Los Angeles | 12 mi | 29 acres |
| Cogswell Reservoir | Los Angeles | 13 mi | 145 acres |
| Legg Lake | Los Angeles | 19 mi | 42 acres |
Straight-line distance between lake centers.
Facts and Figures
Questions About San Dimas Reservoir
How Big Is San Dimas Reservoir?
San Dimas Reservoir covers 35 acres in Los Angeles County, California.
What Is the Largest Lake in Los Angeles County?
Castaic Lake is the largest lake in Los Angeles County, at 2,008 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 27557349). Verified October 30, 2026.