Gov. Tim Pawlenty has ordered an immediate inspection of all Minnesota bridges that have a similar design to the one that collapsed. Pawlenty said he did not know how many bridges have that design. Meanwhile, Federal investigators say they have a strong chance of determing why the state's busiest bridge fell. Minnesota Public Radio's Elizabeth Stawicki reports: Minnesota Department of Transportation Engineer Dan Dorgan says that in the 1990's, investigators found fatigue cracks on the bridge but subsequent inspections showed no additional cracks or that that the existing cracks were growing.