Iowa’s roads and bridges are in decay, which hampers economic development, an advocacy group said Wednesday.

More than a quarter of major urban roads are in poor condition, and more than a quarter of the state’s bridges are structurally deficient or functionally obsolete, according to the report by TRIP, a national transportation research group based in Washington, D.C.

The group called for added spending on roads and bridges to increase safety and to support economic growth. The report contends that the poor roads cost Iowa drivers $2 billion a year in repairs, extra fuel and higher vehicle operating costs.

Among the other problems cited in the report:

• The Iowa Department of Transportation reports that the state is $215 million a year short in cash for road and bridge projects. State lawmakers are considering a 10 cents per gallon increase in the gasoline tax to cover part of that shortfall.

• Twenty-seven percent of Iowa’s major urban roads and highways have poor pavement, and another 50 percent are in mediocre or fair condition. The rest are in good condition.

• In rural areas, 13 percent of the roads are in poor condition, while 45 percent are in mediocre or fair condition and 42 percent are rated “good.”

• Twenty-one percent of Iowa’s bridges are structurally deficient, meaning they have significant deterioration. An additional 5 percent of Iowa’s bridges are functionally obsolete, with narrow lanes, inadequate clearance or poor alignment.

• Iowa averaged 361 motorist deaths annually between 2009 and 2013.