Old & New Mississippi River Bridges, Minneapolis, Minnesota
Bridgepixing Mississippi River Bridges in the Twin Cities of Minneapolis and St. Paul, Minnesota. In the foreground, the newer green steel Interstate 35W Bridge; and in the background, the historic concrete arch Cedar Ave. Bridge (aka Tenth Ave. Bridge), completed in 1929. Additional Bridge Photos and a Bridge Blog at www.Bridgepix.com.
The I-35W Bridge was a deck-arch truss bridge that carried Interstate Highway 35W across the Mississippi River in Minneapolis in the U.S. State of Minnesota. Located in Hennepin County in the Minneapolis-Saint Paul metropolitan area, it connected the Minneapolis neighborhoods of Downtown East and the University of Minnesota West.
The bridge was built in 1967 by the Minnesota Department of Transportation. On August 1, 2007, it collapsed into the river and onto the adjacent riverbanks during the weekday rush hour, causing multiple injuries and deaths.
The I-35W bridge was notable for not having any piers in the water. Instead, the main support piers were located on the banks of the river, and were built of tubular-shaped concrete pillars. The main bridge deck was supported by a single 458 foot long steel arch over a 390 foot wide navigation channel. Two sets of locks and dams just upriver of the bridge were constructed a few years earlier to allow passage past Saint Anthony Falls. Although not very decorative, the bridge was one of the widest bridges in the Twin Cities area and provided an important link for Interstate 35W traffic. According to the Minnesota Department of Transportation, 141,000 cars used the bridge per day and was usually an eight-lane thoroughfare, carrying four lanes of traffic in each direction.
As the bridge was subjected to Minnesota's cold weather in the winter, it acquired another unique feature when an anti-icing system was installed in 1999. When sensors detected temperatures conducive to icing conditions, nozzles built into the bridge sprayed potassium acetate on the road surface. A similar system was later installed on the Brooklyn Bridge in New York. (Wikipedia)