On 1 August 2007 at 6:05 pm, during rush hour traffic, the I35-W Highway Bridge in Minneapolis, Minnesota collapsed into the Mississippi River.

We’ll look at how a bridge could suddenly collapse after 40 years of service. And we’ll ask was there an issue with design, or was there abnormal bridge loading at the time of the failure? Or was there both?

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The National Transportation Safety Board's report can be found at https://www.ntsb.gov/investigations/AccidentReports/Reports/HAR0803.pdf

A photograph of the loading on the bridge can be found in the NTSB failure report on page 26, see figure 16.