The bridge collapse in Minneapolis last week makes us question the safety of our local bridges. There are several reports on the Colorado Department of Transportation website that examine bridge construction and evaluate the state of bridges in Colorado. In addition, the CDOT Design and Construction Support page has manuals for bridge design, bridge ratings, and the "Bridge Field Log of Structures" which includes a list of all the bridges in Colorado with location, span information, and other data. The U.S. Department of Transportation has also released a report: "2006 Status of the Nation's Highways, Bridges, and Transit: Conditions and Performance" which may be of interest.
We also have a very interesting book in our collection available for loan: "Spanning Generations: The Historic Bridges of Colorado" (TRA1.2/B76/2004) from the Department of Transportation that contains a pictorial history of Colorado bridges, including a chapter on bridge types. If you feel like a drive in the high country, we have a pamphlet for "Driving Tours of Historic Bridges in Fremont County and near Interstate 70 west of Denver." (TRA1.2/B76/2004/2)