Roughly 8.8 percent of Minnesota's bridges are “structurally deficient” by government standards, according to a report released Tuesday.

The report, called “The Fix We're In: The State of Minnesota's Bridges,” was compiled by Transportation for America, a coalition focused on transportation reform. The group comprises business, environmental, public health, and transportation organizations, as well as housing and real estate associations, among other groups.

In a ranking of the 50 worst states for bridge conditions, Minnesota ranked 34th. Of the state's 13,068 bridges, 1,149 were assigned a structurally deficient rating by the Federal Highway Administration (FHWA). The rating designates bridges that require significant maintenance, rehabilitation, or replacement.

Federal law requires states to inspect all bridges that are 20 feet or longer every two years. Structurally deficient bridges, however, must be inspected annually.

Nationally, 69,223 bridges-more than 11 percent of total highway bridges-are classified as structurally deficient.

According to the report, most bridges are designed to last about 50 years-regardless of the amount of wear that they endure from motorists and other factors. Minnesota's bridges on average are about 35 years old, shy of the national average of 42 years old.

But there are currently about 2,900 bridges in Minnesota that are older than 50 years-and a “tidal wave” of bridges will reach the 50-year benchmark during the next two decades, boosting that figure to more than 7,200 bridges by 2030, according to the study.

“Preserving Minnesota's existing transportation system is crucial to ensuring regional prosperity, safety, and a higher quality of life,” James Corless, director of Transportation for America, said in a statement. “The economic and social cost of neglect is simply too high. It is time for our policymakers to shore up our infrastructure and ensure Americans get the most bang for our transportation buck.”

Minnesotans cross structurally deficient bridges every day, but some are more heavily traveled than others. Topping the list of poorly rated bridges based on traffic volume are three bridges on Interstate 35E in Ramsey County. The bridge that crosses Pennsylvania Avenue, for example, is considered structurally deficient but accommodates an average of 154,000 motorists each day.

The report states that current federal funding allocations are insufficient to keep up with the nation's quickly deteriorating bridges. Transportation for America suggests increasing federal aid to states for bridge upkeep-a measure it says is more cost-efficient than waiting until bridges require significant maintenance or rebuilding. The group also urges Congress to take steps to ensure that federal funding allocated to states for bridge repair is used for that purpose alone.