Lakes / California / Butte County / Thermalito Afterbay
Thermalito Afterbay, California
4,075 acres
Surface Area
Where It Sits, and How Deep It Goes
Locator - California
39.48 degrees N, 121.67 degrees W - Butte 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 Thermalito Afterbay Stacks Up
- Larger than 96% of the 1,147 lakes counted in California.
- About 62 miles from Sacramento, as the crow flies.
Lakes Nearby
| Lake | County | Distance | Surface Area |
|---|---|---|---|
| Thermalito Forebay | Butte | 4.5 mi | 576 acres |
| Thermalito Diversion Pool | Butte | 8.6 mi | 312 acres |
| Miners Ranch Reservoir | Butte | 11 mi | 49 acres |
| Lake Wyandotte | Butte | 14 mi | 37 acres |
| Lake Oroville | Butte | 14 mi | 10,612 acres |
| Eddy Lake | Butte | 17 mi | 91 acres |
Straight-line distance between lake centers.
Facts and Figures
Questions About Thermalito Afterbay
How Big Is Thermalito Afterbay?
Thermalito Afterbay covers 4,075 acres in Butte County, California.
What Is the Largest Lake in Butte County?
Lake Oroville is the largest lake in Butte County, at 10,612 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 129660125). Verified October 30, 2026.