The Southwest Fifth St. Bridge is an historic structure located in downtown Des Moines, Iowa, United States. Built in 1898 after a controversy surrounding the bidding process, it is one of the last Pratt through truss bridges left in an urban setting in Iowa. The bridge was listed on the National Register of Historic Places in 1998 as a part of the Highway Bridges of Iowa MPS.
The Southwest Fifth Street Bridge is one of a few pinned Pratt through truss bridges with three or more spans left in the state of Iowa.It is also one of only three left in an urban setting in the state. The structure is composed of three six-panel, pin-connected steel Pratt through trusses. Each span is 135 feet (41 m) for a total span length of 401 feet (122 m). The roadway is 30 feet (9 m) wide.The steel structure rests on top of stone abutments and steel cylinder piers filled with concrete.