The number of bridges in Minnesota deemed structurally deficient has grown by 40 over the past two years, and just over 9 percent of the state's bridges are in need of significant maintenance, rehabilitation or replacement according to a report out Wednesday by a national transportation lobby group.

Minnesota was one of 14 states that had an increase in the number of deficient bridges since Transportation for America last surveyed states in 2011. The report titled "The Fix We're in For: The State of Our Nation's Bridges" found that 1,191 of the state's 13,109 bridges were deficient, up from 1,151 two years ago.

Minnesota's bridges are in better shape than in other parts of the country, including three of its neighbors. Nationally 11 percent of bridges -that's one out of nine- are in need of repairs. In Iowa, 21.2 percent of bridges were deemed structurally deficient, ranking it as third worst in the country. South Dakota was right behind in fifth place at 20.6 percent and North Dakota was seventh at 16.8 percent. Wisconsin came in at 36th on the list with 8.2 percent. Minnesota was 32nd.

The worst bridges are in Pennsylvania where 24.5 percent of bridges are considered structurally deficient. Oklahoma was second worst with 22.6 percent. Nevada and Florida had the fewest percentage of bridges in question with 2.2 percent each.

Americans make more than 260 million trips over structurally deficient bridges each day. In Minnesota, 2.3 million vehicles use deficient bridges each day, according to the report compiled with data obtained from the Federal Highway Administration.

While most of the 66,405 bridges across the nation deemed as structurally deficient may not pose an immediate threat to the public, ignoring repairs can increase the likelihood of the imposition of weight restrictions, sudden closures or worse, a collapse such as the I-35W Bridge collapse in Minneapolis on Aug. 1, 2007. Last month a bridge in Washington state collapsed, although it was not determined to be structurally deficient.

"We are not giving bridge repair the attention and investment it deserves," said James Corless, director of the Washington D.C.-based advocacy group that lobbies to improve transportation.

The Federal Highway Administration found that repairing deficient bridges would cost more than $76 billion, and the bill could get larger. The average age of a bridge in the United States is 43 years old, with most designed to last 50 years before significant repairs are required. Within 10 years, more than 25 percent of bridges (170,000) will be older than 65, well beyond their life expectancy.

Andrew Hermann, former president of the American Society of Civil Engineers, said Minnesota's problems stem largely on a reluctance on the part of political leaders to provide funding.

Money is a problem on the national level, too. Money from the gas tax goes to help fund road construction and repair. It's currently at 18 cents per gallon has not been raised since 1993. With declining gas tax revenue, there is less money for state's transportation departments.

Compounding the problem was a change in federal funding approved last year. The new MAP-21 funding system in place until 2014 eliminated a dedicated fund for bridge repair. Those projects now must compete with other transportation for funding. Additionally, with MAP-21, money previously targeted for bridge repair was rolled into a National Highway Performance Program. That money can only be spent on roads and projects that are part of the National Highway System, which includes interstates and major state highways. Consequently, more than 180,000 deficient bridges are not eligible for federal funding.

"With the collapse of the I-5 bridge in Washington state last month, coming just six years after an interstate collapse in Minnesota, Americans are acutely aware of the critical need to invest in our bridges as our system shows its age," Corless said.

To remedy the problem, Corless said congress must raise additional revenue for the nation's surface transportation system and that money for bridge and highway repair must be made a priority.