Timeline
Aug. 1, 2007, 6:05 p.m. - I-35W Bridge over the Mississippi River in Minneapolis collapses. State and local emergency response is immediate. Roadwork on detours begins, including converting Hwy 280 to a freeway overnight and adding lanes and ramps to other highways to accommodate displaced traffic.
Aug. 2, 2007 - Minnesota Gov. Tim Pawlenty orders a review of state bridge inspection processes and protocols and an emergency inspection of similar bridges.
Aug. 3, 2007 – Mn/DOT forms a team to begin planning for a replacement bridge.
Aug. 4, 2007 – Roadwork on detours continues.
Aug. 6, 2007 – FBI and U.S. Navy divers arrive with special equipment to help with recovery efforts. Demolition begins to aid recovery operations.
Aug. 20, 2007 – Rescue and recovery efforts completed, Mn/DOT begins demolition of the bridge and debris removal.
Aug. 23, 2007 – Preliminary plans for a replacement bridge are made public for citizen comment.
Sept. 6, 2007 – Army Corps of Engineers opens the Lower St. Anthony Falls lock to limited commercial barge traffic.
Sept. 14 - Oct. 8, 2007 – Mn/DOT awards design-build contract to Flatiron/Manson for the design and construction of the new I-35W Bridge.
Nov. 1, 2007 – Major work on the new bridge begins.
Dec. 21, 2007 – Mn/DOT completes special inspections for more than 4,000 state and local bridges.
Jan. 15, 2008 – National Transportation Safety Board conducts a news conference and issues a letter citing inadequacy in the original design of gusset plates for the bridge. NTSB Letter
They further recommend that officials conduct load capacity calculations to verify all structural elements, including gusset plates, whenever modifications are planned to a bridge. Mn/DOT begins performing these load capacity calculations and makes field inspections on all 25 state steel truss bridges.
NTSB load capacity calculations news release
Feb. 25, 2008 – State Transportation Funding Bill authorizes $4.5 billion in revenue and $1.8 billion in bonds over the next 10 years.
March - June 2008 – Examination of gusset plates leads to the closure, repair or replacement of several Minnesota bridges.
June 16, 2008 – Mn/DOT announces a $2.5 billion Bridge Plan to replace or rehabilitate 120 bridges across the state within 10 years.
June 19, 2008 – Mn/DOT announces that the new I-35W bridge may open about two months ahead of schedule.
A message from Transportation Commissioner Tom Sorel
On Aug. 1, 2007, Minnesota suffered a tragedy of historic proportions when the I-35W bridge collapsed. Our hearts continue to go out to the victims, families and others affected by the collapse. We recognize that the tragedy, although local, affected the entire nation as the safety of the nation’s bridges was questioned and placed in a spotlight never before experienced.
Safety is our top priority
Bridge inspections: Mn/DOT is dedicated to never letting a bridge collapse happen again. In the year since the I-35W bridge tragedy, we have reviewed our inspection policies and procedures and examined more than 4,000 bridges across the state.
- Policies and procedures: Immediately following the I‐35W Bridge collapse, Gov. Tim Pawlenty requested a “stem to stern review” of Mn/DOT bridge inspection policies and procedures. Mn/DOT entered into an agreement with PB Americas to review the bridge inspection program and determine its compliance with the National Bridge Inspection Standards. View June 26, 2008 final report (PDF)
- Inspections: Bridge inspectors from Mn/DOT, local governments and consulting firms examined more than 4,000 bridges, including 3,875 bridges on the state trunk highway system and 843 local bridges classified as structurally deficient. In addition, bridges with a gusset plate design underwent special in-depth inspections. More about statewide bridge inspections
Bridge repairs and replacement: Mn/DOT has completed the review of gusset plates for all 25 truss bridges on Minnesota state highways. As a result of special inspections of state bridges with gusset plates, three state bridges were fully or temporarily closed while repairs could be made or the bridge replaced.
- Winona Hwy 43: The bridge was closed on June 3, 2008 due to rust and corrosion found in gusset plates at several locations of the bridge. The bridge was temporarily closed for all traffic while further inspections and repairs were completed. The bridge is now open to traffic but remains closed to bicycles and pedestrians.
- St Cloud Hwy 23: The bridge closed permanently on March 20, 2008. It will be replaced starting in 2008.
- Blatnik Bridge in Duluth: The bridge was restricted on May 6, 2008 to one lane in each direction pending repairs to gusset plates. Work to strengthen gusset plates was completed July 21, 2008.
Determining the cause of the I-35W bridge collapse: The cause of the collapse has not yet been determined. Several investigations are underway, and the results of these investigations will have nationwide impact on ensuring bridge safety.
- The National Transportation Safety Board investigation is expected to be completed later this year. The NTSB will not only report the cause of the collapse, but also will issue recommendations to prevent bridge failures from similar causes. The NTSB work and any subsequent Federal Highway Administration policy changes will be the definitive reports on the I-35W Bridge for state transportation agencies. NTSB
The future of Minnesota bridges: Work on the new I-35W bridge is almost complete and Mn/DOT has developed a plan to replace or rehabilitate more than 120 state bridges by 2018.
- Rebuilding the I-35W bridge: Construction began in October 2007 and will be complete in fall 2008.
- Hwy 61 Hastings bridge: Construction of a new bridge will begin in the summer of 2010.
- State bridge plan: Mn/DOT plans to replace or rehabilitate 120 bridges across the state by 2018 for the cost of $2.5 billion over 10 years. The plan specifically addresses bridges that are either fracture critical or have a low sufficiency score. These bridges include major replacement projects like I-90 over the Mississippi near Dresbach, the I-35E Cayuga Bridge in St. Paul and the Hwy 36 St. Croix River crossing south of Stillwater.
More information about bridge inspections and the collapsed bridge is available on the I-35W Bridge Collapse Web site.