Last reviewed July 2026.
Minnesota Issue Guide
Minneapolis Interstate 35W Bridge Collapse
This guide is compiled by staff at the Minnesota Legislative Reference Library on a topic of interest to state legislators. It introduces the topic and points to sources for further research. It is not intended to be exhaustive.
Timeline • Internet Resources • Articles • Books and Reports
On August 1, 2007, the Interstate 35W bridge in Minneapolis, spanning the Mississippi River near downtown, collapsed during heavy rush-hour traffic as vehicles crept through an active construction zone. The collapse involved 111 vehicles, killing 13 people and injuring another 145.
The National Transportation Safety Board (NTSB) ultimately determined that the probable cause of the collapse “was the inadequate load capacity, due to a design error . . . of the gusset plates at the U10 nodes, which failed under a combination of (1) substantial increases in the weight of the bridge, which resulted from previous bridge modifications, and (2) the traffic and concentrated construction loads on the bridge on the day of the collapse.”
A replacement bridge was designed and constructed on an accelerated schedule, opening less than a year after the collapse on September 18, 2008.
The investigation and recovery efforts prompted broader questions about bridge safety and infrastructure oversight throughout the United States.
In the aftermath of the event, citizens and government officials in Minnesota sought access to Minnesota Department of Transportation (MnDOT) inspection reports, Federal Highway Administration documents, and other records related to the history, maintenance, and safety of the I-35W bridge—and all other bridges in the state.
This guide compiles many of those reports and provides links to materials documenting the State of Minnesota’s response to the collapse and its efforts to quickly replace a critical crossing over the Mississippi River.
Interstate 35W Bridge Collapse and Reconstruction Timeline
This chronology presents key events related to the I-35W bridge collapse and the subsequent construction of a replacement bridge.
August 1, 2007: Shortly after 6:00PM, the I-35W Bridge collapsed while carrying 111 motor vehicles.
August 4, 2007: MnDOT issued a request for qualifications for a Design Build Contract for the replacement of the I-35W Bridge. Congress authorized approximately $250 million for reconstruction of the bridge.
August 14, 2007: The Minnesota Legislature established a Joint Committee to Investigate the Bridge Collapse to Investigate the Bridge Collapse, composed of sixteen legislators from the House and Senate transportation committees. The Committee was charged with conducting a comprehensive review of MnDOT’s decisions related to the collapse.
August 20, 2007: The body of the 13th and final victim of the collapse was recovered from the Mississippi River.
August 23, 2007: MnDOT released a request for proposals for the replacement bridge.
September 11, 2007: The Minnesota Legislature held a one-day special session. Enacted legislation included several provisions related to the collapse (see Laws of Minnesota 2007, 1st Special Session, chapter 2).
September 14, 2007: MnDOT received technical proposals from four firms: Ames/Lunda, C.S. McCrossan, Flatiron/Manson, and Walsh Construction/American Bridge.
September 18, 2007: MnDOT received financial proposals.
October 5, 2007: The City of Minneapolis passed a resolution approving MnDOT’s proposed bridge layout by resolution.
October 8, 2007: MnDOT awarded the construction contract to Flatiron/Manson.
October 15, 2007: The Transportation Contingent Advisory Group authorized MnDOT to spend an additional $60 million through February 2008. This amount was below the $195 million requested.
October 16, 2007: MnDOT was sued over the selection of the winning bidder. The lawsuit alleged that the bidding process unfairly favored Flatiron/Manson and sought to halt construction (Sayer and Phillippi vs Minnesota Department of Transportation; Case No. 62-CV-07-3425).
October 31, 2007: The court denied a request for a restraining order that would have halted construction (Sayer and Phillippi vs Minnesota Department of Transportation; Case No. 62-CV-07-3425).
November 1, 2007: Construction of the replacement bridge began.
November 29, 2007: Governor Tim Pawlenty and state legislators announced the creation of the I-35W Emergency Hardship Relief Fund, which provided $1 million in financial assistance to victims of the collapse and their families. Eligible recipients could receive $10,000 in lost wages.
December 19, 2007: The Minnesota Legislature’s Joint Committee to Investigate the Bridge Collapse authorized up to $500,000 for an investigation of MnDOT and the I-35 Bridge collapse to be conducted by the law firm Gray Plant Mooty. The report was scheduled for completion in May 2008.
January 11, 2008: The National Transportation Safety Board (NTSB) identified a design error involving undersized gusset plates on the I-35W Bridge 9340’s main trusses. On January 15, 2008, the NTSB issued Safety Recommendation H-08-1 regarding load-capacity calculations for non-load-path-redundant steel truss bridges in the United States. These findings were included in the Federal Highway Administration’s interim report, Adequacy of the U10 and L11 Gusset Plate Designs for Minnesota Bridge No. 9340 (I-35W Over the Mississippi River).
February 19, 2008: The Office of the Legislative Auditor, building on its 1997 report Highway Spending, released an updated analysis, State Highways and Bridges.
March 5, 2008: The NTSB issued Structural Investigation Group Chairman Factual Report 08-015 (TG25.M6 S77 2008). On March 17, 2008, an NTSB update stated that excess construction weight had been placed above previously identified undersized gusset plates.
May 8, 2008: Governor Pawlenty signed a $38 million package to compensate bridge victims for their injuries and losses.
May 21, 2008: The Joint Committee to Investigate the Bridge Collapse released its report, Investigative Report to Joint Committee to Investigate the I-35W Bridge Collapse.
September 18, 2008: The replacement bridge opened.
November 14, 2008: The NTSB issued their report, Collapse of I-35W Highway Bridge Minneapolis, Minnesota, August 1, 2007.
November 18, 2008: MnDOT issued its formal response to the NTSB report.
August 23, 2010: URS Corporation agreed to pay $52.4 million to victims of the bridge collapse.
August 1, 2011: The I-35W Bridge Remembrance Garden, located near Gold Medal Park, was unveiled by Governor Mark Dayton and Minneapolis Mayor R.T. Rybak.
Significant Internet Resources
Minnesota Department of Transportation (MnDOT)
Minnesota Legislature
Joint House Transportation Finance Division and Senate Transportation Budget and Policy Division Committee
Legislative History
- On August 4, 2007 both the United States House and Senate authorized approximately $250 million for reconstruction of the I-35W Bridge in H.R. 3311. The law was signed by the President George W. Bush on August 6, 2007 (see P.L. 110-56).
- On September 11, 2007, the Minnesota Legislature held a special session. Several provisions related to the I-35W Bridge were included in Laws of Minnesota 2007, 1st Special Session, chapter 2, article 2, such as $2 million provided for state matching funds needed to receive federal disaster assistance and a prohibition for insurance companies to state or imply that a policyholder filing a no-fault motor vehicle insurance claim related to the bridge collapse could result in non-renewal, cancellation, or premium increase.
- On May 8, 2008, Governor Tim Pawlenty signed a $38 million compensation package for victims of the I-35 Bridge collapse in Laws of Minnesota 2008, chapter 288.
Emergency Declarations
- A peacetime emergency was declared by Executive Order issued by Governor Tim Pawlenty. The order and its 30-day extension by the Executive Council of the State of Minnesota are avaliable for public reference.
- A Presidential Emergency Declaration was issued by President George W. Bush in a letter to Governor Tim Pawlenty.
Minnesota Historical Society
I-35W Bridge Collapse - MNopedia entry
Federal Government
National Transportation Safety Board (NTSB)
NTSB Docket ID Number: HWY07MH024 - August 1, 2007, Minneapolis, Minnesota - Contains a list of NTSB documents associated with the bridge collapse investigation.
Other
Significant Articles
(articles in reverse chronological order)
Bickal, Jim, and Sara Porter. "Reporting, Memories From the I-35W bridge Collapse." Minnesota Public Radio, August 1, 2017.
Bierschbach, Brianna. "What is the Legacy of the 35W Bridge Collapse on Minnesota Politics and Policy?" MinnPost, August 1, 2017.
Bakst, Brian. "Since I-35W, State Has More Eyes and Sharper Focus on Bridges." Minnesota Public Radio, July 31, 2017.
Adriaens, Emily. "2007 Special Session Fiscal Summary of Disaster Relief." Money Matters (Minnesota House of Representatives, Fiscal Analysis Department), October 2007, p. 1-6.
"Aging Infrastructure: Is Neglected Maintenance Putting Americans in Danger?" CQ Researcher, September 28, 2007, p. 793-816.
Cook, Mike. "Disaster Relief Package Enacted." Session Weekly, September 12, 2007, p. 1-2.
Significant Books and Reports
Adequacy of the U10 and L11 Gusset Plate Designs for the Minnesota Bridge No. 9340 (I-35W Over the Mississippi River). Washington, DC: Federal Highway Administration, Turner-Fairbank Highway Research Center, 2008. (TG25.M6 H65 2008)
Ballarini, Roberto, and Taichiro Okazaki. The Infamous Gusset Plates. Minneapolis: University of Minnesota [?], 2009. (TG25.M6 B35 2009)
Bridging the Gap: Restoring and Rebuilding the Nation's Bridges. American Association of State Highway and Transportation Officials, 2008. (TG23 .B75 2008)
Bridging the Mississippi: The New I-35W Bridge: Minneapolis, Minnesota. (Dedication Day 2008 Commemorative Book) FIGG, 2008. (TG25.M6 B75 2008)
Collapse of I-35W Highway Bridge Minneapolis, Minnesota, August 1, 2007. Washington DC: National Transportation Safety Report, 2008. (TG25.M6 I253 2008)
Economic Impacts of the I-35W Bridge Collapse. St. Paul: Minnesota Dept. of Employment and Economic Development, Minnesota Dept. of Transportation, 2009? (TG25.M6 E36 2009)
The End of the Road: Challenges of Funding Minnesota's Local Road and Bridge Network. St. Paul, Minn.: Bonestroo, 2007. (HE356.M6 E53 2007)
Fatigue Evaluation and Redundancy Analysis: Bridge 9340, I-35W Over Mississippi River. (Draft report). Minneapolis: URS Corporation, 2006. (TG25.M6 F38 2006)
Fracture Critical Bridge Inspection: In-Depth Report, Bridge #9340 (Squirt Bridge): I-35W Over the Mississippi River at Minneapolis, MN. St. Paul: Minnesota Dept. of Transportation, 2006. (TG25.M6 F85 2006)
Hartgen, David T. and Ravi K. Karanam. 17th Annual Report on the Performance of State Highway Systems (1984-2006). Los Angeles: Reason Foundation, 2008. (TE220 .H37 2008)
Highway Spending: a Program Evaluation Report. St. Paul: Office of the Legislative Auditor, 1997. (HE355 .H56 1997 ) Note: In August 2007, the Joint Legislative Committee to Investigate Bridge Collapse asked the Office of the Legislative Auditor to update this report. The resulting report, State Highways and Bridges, was published in February 2008.
I-35W Bridge Collapse and Response: Minneapolis, Minnesota. U.S. Fire Administration/Technical Report Series, FEMA, 2008. (TG25.M6 S73 2008)
I-35W Bridge over the Mississippi River Collapse Investigation: Bridge no. 9340: Minneapolis, Minnesota. (Consultants report prepared by Wiss, Janney, Elstner Associates.) Oakdale, Minnesota: Minnesota Department of Transportation Bridge Office, 2008. (TG25.M6 I 254 2008)
Infrastructure 2008: A Competitive Advantage. Washington D.C.: Urban Land Institute, 2008. (HC79.C3 I54 2008)
Investigative Report to Joint Committee to Investigate the I-35W Bridge Collapse. Minneapolis: Gray Plant Moody, 2008. (TG25.M6 I25 2008)
Kirk, Robert S. and William J. Mallett. Highway Bridges: Conditions and the Federal/State Role. Washington, DC: Congressional Research Service, 2007.
LePatner, Barry B. Too Big to Fail: America's Failing Infrastructure and the Way Forward. New York: Foster Publishing, 2010. (HE206.2 .L47 2010) This book addresses the I-35 bridge collapse in detail.
Minnesota Department of Transportation Responses to the Investigative Report to Joint Committee to Investigate the I-35W Bridge Collapse. Minnesota Department of Transportation, 2008. (TG25.M6 I252 2008)
MnDOT's Response to National Transportation Safety Board Recommendations. St. Paul: Minnesota Dept. of Transportation, November 18, 2008. (TG25.M6 I2532 2008)
National Bridge Inspection Standards Compliance Review Report. St. Paul: Minnesota Dept. of Transportation, Office of Bridges and Structures, 2008. (TG315 .N38 2008)
Nunnally, Patrick. The City, the River, the Bridge: Before and After the Minneapolis Bridge Collapse. Minneapolis: University of Minnesota Press, 2011. (HN80.M6 C57 2011)
O'Connell, Heather M., Robert J. Dexter, and Paul Bergson. Fatigue Evaluation of the Deck Truss of Bridge 9340. St. Paul: Minnesota Dept. of Transportation, Office of Research Services, 2001. (TG25.M6 O36 2001)
Report on Expenditure of I-35W Bridge Special Compensation Appropriations. St. Paul: Minnesota Management & Budget, 2009. (HJ7599 .R47 2009) (Mandated by: 2008 Minn. Laws Chap. 288 Sec. 6 Subd. 5)
Road User Cost Due to Unavailability of Interstate 35W Mississippi River Crossing at Minneapolis, Minnesota. St. Paul: Minnesota Dept. of Transportation, 2007. (TG25.M6 R63 2007)
Stambaugh, Hollis and Harold Cohen. I-35W Bridge Collapse and Response, Minneapolis, Minnesota, August 1, 2007. Emmitsburg, Md.: Federal Emergency Management Agency, Department of Homeland Security, United States Fire Administration, National Fire Programs Division, 2008. (TG25.M6 S73 2008)
State Highways and Bridges. St. Paul: Office of the Legislative Auditor, 2008 [includes 2010 update]. (HE355.H562 2008) The Legislative Auditor was requested to update their 1997 report, Highway Spending, shortly after the 35W bridge collapsed.
Truss Bridges: Trunk Highway Bridges and Local Bridges. St. Paul: Minnesota Dept. of Transportation, 2008. (TG24.M6 T78 2008)
Wattson, Peter. Compensating Victims of Bridge Collapses Outside Minnesota. St. Paul: Senate Counsel, 2007. (TG470.W38 2007)
Additional Library Resources
For historical information, check the following codes in the Newspaper Clipping File and the Vertical File:
B28