Historic Name: Seventh Street Improvement Arches
Mn/DOT Bridge Number: Bridge No. 90386
Bridge Type: Masonry arch
City/Township: St. Paul
Crossing: 7th St. E. over railroad tracks
Engineer: William A. Truesdell
Contractor: Michael O’Brien; McArthur Brothers, Chicago
Year Built: 1883-1884
Span Length: west arch, 41 feet; east arch, 30 feet
Length of Arch Barrel: 124 feet
Adapted from the National Register of Historic Places nomination form prepared by Jeffrey A. Hess. The Seventh Street Improvement Arches were listed on the National Register of Historic Places in 1989.
Summary of Historic Significance
The Seventh Street Improvement Arches are a skewed, double-arched, masonry highway bridge constructed according to the helicoidal or spiral method. The Seventh Street Improvement Arches are historically significant for its rarity and the technically demanding nature of its skewed, helicoidal, stone-arch design. At the time of its construction in 1884, the bridge was thought to be one of the few of its type in the United States and today it is the only known example in Minnesota.