Before August 2007…

Pre 1964

• The civil engineering firm of Sverdrup & Parcel designs the original I-35W arch deck truss bridge, known as Bridge 9340, over the Mississippi River. Leif Sverdrup (deceased) founded the firm 1 April 1928. The firm is now part of Jacobs Engineering, Inc.

1964

• Hurcon Inc. and Industrial Construction Company begin construction of the 35W Bridge. Both companies are out of business. Construction plans and drawings can be viewed at the Mn/DOT website: 1964 plans, 1965 plans, undated plans.

  28 October 1969 - Aerial view of 35W Bridge   (Photo provided by WRIT 4662W (Umn)

  2 November 1966 - Aerial view of 35W Bridge construction   (Photo provided by WRIT 4662W (Umn)

1965

• Industrial Construction Company constructs the bridge's steel trusses and deck.

1967

• The original I-35W Bridge opens for traffic.

1977

• Structural repairs (drawings) are made to the 35W Bridge.

1985

• Structural repairs (pier cap repair drawing 1, pier cap repair drawing 2, ) are made to the 35W Bridge.

1990

• The federal government rates the 35W Bridge as “structurally deficient” and mentions significant corrosion in its bearings.

1998

• Additional structural repairs (deck repair drawings 1, repair crack at girder G2 drawing) are made on the bridge.    

1999

• Additional structural repairs (drawings) are made on the bridge.
• An automatic de-icing system is installed on the bridge deck and railings by Boschung, a Swiss company (Thawspray drawing, Operational Evaluation Report).

March 2001

• University of Minnesota engineers issue a report that rates the 35W Bridge as structurally deficient, but not in need of immediate replacement.

15 June 2006

• URS, Inc., a San Francisco-based consulting firm, completes the last full inspection of the bridge and recommends reinforcing 52 trusses. 

   

October 2006

• Mn/DOT’s Bridge Office requests money from the state, and is funded with $1.5M, for reinforcing the 35W Bridge. 

   

19 December 2006

• Mn/DOT is told ultrasonic inspections are an alternative to installing reinforcing plates. URS sends Mn/DOT a draft with three revised options: reinforce 52 beams, inspect the beams with ultrasonic equipment, or a combination of reinforcing 24 beams and inspecting the other 28.

17 January 2007

• State Bridge Engineer Dan Dorgan and staff opt for inspection only, saying the decision is based on URS assurances that inspectors can detect and isolate cracks before they reach a dangerous length.

18 January 2007

• Senior Engineer Gary Peterson tells Mn/DOT's Metro Division the plate-installation project will be delayed.

May 2007

• Inspections of critical beams begin on half of the designated beams. Inspections are halted when the summer repair work begins.

Summer 2007

• Structural repairs are made on the bridge (drawings). The work includes concrete and joint repair, lighting and guardrail installation and is scheduled to be completed by 30 September 2007.

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