| Byllesby Dam | |
| Location Map: | Minnesota |
| Coordinates: | 44.5118°N -92.9401°W |
| Country: | United States |
| Location: | Dakota County and Goodhue County, Minnesota |
| Status: | O |
| Opening: | 1910 |
| Owner: | Dakota County, Minnesota |
| Dam Type: | Concrete gravity dam |
| Dam Height: | 75feet |
| Dam Crosses: | Cannon River |
| Res Name: | Lake Byllesby |
| Res Surface: | 1432acres |
Lake Byllesby Dam is a concrete gravity dam located in Randolph Township, Dakota County and Stanton Township, Goodhue County, Minnesota, just west of the city of Cannon Falls. It is approximately southeast of the Twin Cities.
The 75feet-high dam was built in 1910 by H.M. Byllesby & Company to impound the Cannon River for hydroelectric power. Its nameplate capacity is 1.8 MW.[1] [2] Byllesby, a former employee of both Edison and Westinghouse, formed what would become Northern States Power in 1909.[3]
The dam created Lake Byllesby, with a surface area of and a capacity of .
The facility is owned and operated by Dakota County.