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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.
  • Brochure

2015 lockage service hours

Lock & Dam 1

Open daily
3 a.m.-10 p.m.

Recreation Opportunities

The observation deck is open daily from 7 a.m. to 8 p.m.

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