ST. PAUL, Minn. -- Minnesota appreciates the progress the NTSB has made in the investigation and its willingness to share preliminary findings.

The findings announced today by the NTSB about the gusset plates are valuable not only to Minnesota but the nation.

Because the NTSB first noted concerns about weight loads and gusset plates in August, Mn/DOT took a proactive step in beginning a review of the design of gusset plates on similar truss bridges in Minnesota.

Mn/DOT already has started reviewing these gussets on existing truss bridges similar to I-35W and will expand that review to include all truss bridges. There are 23 truss bridges on the state highway system
and 36 on the local road system. See Minnesota Highway Truss Bridge Lists (39kb PDF, 2 pages)

Mn/DOT has completed the gusset check on the Highway 23 bridge over the Mississippi River in St. Cloud and no deficiency has been found.

Mn/DOT staff also has completed checking the most heavily loaded gussets on Highway 243 bridge over the St Croix River near Osceola; and the Highway 123 bridge over the Kettle River near Sandstone. No deficiencies have been found and they are in the process of developing computer models of both bridges to complete all gusset checks. That is expected in the next month.

Mn/DOT has also retained two engineering firms to perform load ratings on several truss bridges, these are among Mn/DOT's larger trusses of complex design. Those firms are LHB Engineers of Duluth and WSB and Associates of Minneapolis. Mn/DOT has expanded that work to include a review of gusset plates. The bridges involved in those contracts are:

• Highway 43 over the Mississippi at Winona
• Highway 23 over the Mississippi in St. Cloud (gusset plate
  review completed)
• Highway 61 over the Mississippi at Hastings
• Highway 63 over the Mississippi at Red Wing
• Highway 2 over the Red River at Grand Forks
• Highway 535 in Duluth - Blatnik Bridge
• Highway 99 over the Minnesota River at St. Peter

As of the NTSB announcement today and the Governor's direction, MN/DOT will retain additional consultants and use Mn/DOT engineering staff to complete gusset checks on all 23 state highway bridges that are high
truss designs.

This work is scheduled to be complete in June of 2008.

Mn/DOT will coordinate with local governments on the review of their truss bridges.

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