At that point in history, Minneapolis was on the west bank of the Mississippi River, which was the south side of the river in the falls area. The north side of the river was occupied by the City of Saint Anthony. In 1872, the two cities agreed to merge, with the unified city keeping the name Minneapolis. As part of the merger deal, the city of Minneapolis agreed to rebuild the Upper Bridge and the Lower Bridge. Previous bridges were privately owned and charged tolls for users. The new bridges would be paid for by $230,000 in public bonds.
The new Lower Bridge was built by the King Bridge Company of Topeka, Kansas. The bridge featured masonry piers and a long iron truss to support a narrow two lane wagon path across the river. The new lower bridge opened in 1874 after 15 years of the First Bridge being the only road bridge to cross the Mississippi River in Minneapolis. Street cars became popular in the 1890s, and a street car line was built across the Lower Bridge prior to the turn of the century.
The Lower Bridge was lightly built by current standards. The iron structure was not as strong as an equivalent steel structure. The bridge was not built for the weight of the street cars, and it was not designed to withstand the pounding from automobile traffic that developed in the 20th century. As a result, the Lower Bridge was closed in 1934. It stood until 1943, when it was demolished as part of a World War II scrap iron drive.
The lower bridge connected to 6th Avenue SE on the north side of the river. The present day location of the bridge abutment would be just a few feet downriver from the traffic cul-du-sac at the entrance of the Stone Arch Bridge. The south end of the bridge connected to 10th Avenue S. That location would be just downriver from the location of the new Guthrie Theater. As a result its connection to 10th Avenue S, the Lower Bridge was often referred to as the 10th Avenue Bridge. This may be a bit confusing since the current 10th Avenue Bridge is the bridge once known as the Cedar Avenue Bridge. Even more confusing is the current Cedar Avenue Bridge is the structure on MN-77 that crosses the Minnesota River near the Mall of America.
There appears to be no evidence of the lower bridge on the south side of the river. Two bridge piers remain on the north side of the river. One pier is in the water near the University Steam Plant, while the other pier is in the weeds on shore next to the steam plant. The photo above shows the two remaining piers. The photo below is a public domain image of the Lower Bridge from early in the 1900s.