While Iowa looks to restore hundreds of miles of pavement using new gas-tax receipts, the transportation research group TRIP finds that a quarter of major urban roads in the United States are in substandard or poor condition.

That means a rough ride and more expense for motorists.

More findings:

• A full 28 percent of the nation’s major urban roads, such as interstates and freeways, have substandard pavement and provide a bumpy ride.

• An additional 41 percent of the nation’s major urban roads and highways are in mediocre or fair condition, and 31 percent are in good condition.

• Including major rural roads, 18 percent of the nation’s major roads are in poor condition, 40 percent are in mediocre or fair condition, and 42 percent are in good shape.

• Among the 25 largest urban areas, San Francisco had the highest percentage of poor roads at 74 percent. Omaha ranked 23rd at 42 percent.