This image shows the dam and associated locks on the Mississippi River described here at U. S. Government Dam and Locks.
The description states:
GOVERNMENT DAM AND LOCKS AND FORD BRIDGE, MINNEAPOLIS MINN.
Through these locks pass the Mississippi river boats and barges laden with coal, oil and industrial machinery. The head of navigation is at Minneapolis Municipal Dock at Washington Ave. South.
CITY OF LAKES AND PARKS
–The dam was originally built and owned by the Ford Motor Company and are now known as Lock and Dam Number 1. The Ford Bridge in the background is now known as the Intercity Bridge and carried 46th Street between Minneapolis and St. Paul.
This image likely dates from the 1940s.