Lock & Dam 1

  • Located on Mississippi River mile 847.9, in Minneapolis.
  • Construction completed in 1917, reconstructed in 1929. Main Lock completed May 1932. Last major rehabilitation 1978-1983.
  • Dam consists of Ambursen concrete overflow structure 574' long, hydro power station owned and operated by Brookfield Power Co.
  • Lock is 56' wide by 400' long. River Lock 56' wide by 400' long.
  • It is the only twin lock in the district.


Lockage Hours 
Tuesday - Thursday (appointment only)       7 a.m. - 3:30 p.m.
Mondays and Fridays                                       12 p.m. - 6 p.m.
Saturday - Sunday                                             8 a.m. - 6 p.m.

  • Recreators need to be at the lock at least 30 minute prior to the closure to ensure your lockage.
  • To schedule a lockage, please contact the lock staff by Channel 14 on a marine radio; call the lock staff at (651) 290-5919; or pull the recreation pull cord on the lock's guide wall.

‚ÄčMinneapolis locks disposition studies
The district is conducting disposition studies to examine the benefits and costs of continuing to operate federal projects which are no longer serving their authorized purpose.

Recreation Opportunities

In order to protect lock staff and the public from COVID-19 concerns, the Lock and Dam 1 visitor center is currently closed.

Lock and Dam 1
Lock & Dam 1, Minneapolis, Minn.

Contact information

U.S. Army Corps of Engineers
St. Paul District
Lock and Dam 1

5000 West River Parkway
Minneapolis, MN 55417-1609
(651) 290-5919