Hennepin County closed the Lowry Avenue Bridge, effective 10 a.m. April 25, due to known structural issues with one of the bridge’s piers.
In 2004, bridge engineers discovered Pier 3 had rotated 11 inches out of vertical alignment. Further rotation of the pier has introduced an unreasonable risk to the traveling public. The rotation of the pier, coupled with the normal temperature expansion of the superstructure, has created a situation that prevents an accurate determination of the stresses the bridge is experiencing.
The structure, we believe, is not in any imminent danger of collapse, but as the air temperature increases, the situation could change without notice – that is our primary concern, said Hennepin County Transportation Department Director Jim Grube.
County engineers, in consultation with Wiss, Janney, Elstner Associates, determined the bridge should be closed until it can be replaced.
The county has monitored the Lowry Avenue Bridge on a regular basis since engineers discovered foundation problems at Pier 3 on the east side of the Mississippi River navigational channel in fall 2004. The bridge was closed for a year while transportation department engineers and a bridge consultant determined the extent of the problems and installed a new bearing system.
On average, one of the county’s bridge engineers has inspected the bearing assembly once each day for the past two weeks. The bridge is also inspected by certified bridge inspectors once each year, and underwent an in-depth fracture critical inspection in September 2007.
The Lowry Avenue Bridge carries Hennepin County State Aid Highway 153 over the Mississippi River between North and Northeast Minneapolis. The bridge was built in 1905 and substantially renovated in 1958.
Construction of a replacement for the current Lowry Avenue Bridge is scheduled to begin in 2009 with completion in 2011. The county is actively investigating opportunities to speed up the construction start date.
The County Board approved the Lowry Avenue Bridge replacement project as its No. 1 state bonding request in summer 2006. The total estimated cost for the replacement project is approximately $109 million. Funding sources for the project include Hennepin County State Aid and State of Minnesota local bridge bonds. Federal funding is also being pursued.
Images of Pier 3 and more information on the Lowry Avenue Bridge Replacement Project can be found at http://www.lowryavenuebridge.com/