Rapidan Dam

Facts about the Rapidan Dam


Structure


  • Amburson type hollow reinforced concrete
  • Constructed: 1908 - 1910
  • One fatality
  • Height from top of dam to stream bed: 87 feet
  • Length: 475 feet
  • Spillways: 5 steel tainter gaits and 2 timber gates

Generators


  • Two turbines powered by falling water
    • 600 cubic feet per second each
  • Two generators, three million watts each
  • Power for 2,000 to 3,000 residences with both generators running at capacity

Blue Earth River at Dam Partnership


  • Drainage area above dam: 2,430 square miles
  • Blue Earth County owns the dam and reservoir
  • Mean flow: 827 cubic feet per second
  • 100 year flood: 34,600 cubic feet per second
  • North American Hydro owns turbines, generators, electrical equipment, and operates dam
  • Flood of record: 43,100 cubic feet per second
See the current flow.

Reservoir Principal Regulators


  • Extent: 318 acres, 6.3 miles long - Federal Energy Regulatory Agency (FERC)
  • Estimated sediment: 11,000,000 cubic yards - Minnesota Department of Natural Resources (MNDNR)