Meanwhile, none (0 percent) of Utah's freeways was ranked in poor condition (lowest in the nation), 2 percent were mediocre and 8 percent were in fair condition.
Utah has been able to keep its freeways in good condition largely by sacrificing — until this year — the condition of its low-volume state highways in rural areas that had fewer than 1,000 cars per day or 100 trucks per day.
Carlos Braceras, executive director of the Utah Department of Transportation, has said his agency realized about nine years ago that "we did not have enough money to maintain all of our roads in a proactive way."
So it intentionally stopped maintaining those low-volume rural roads — simply fixing problems as they occurred. It used the money saved to maintain the freeways and other high-volume state highways.
Last year, the Legislature passed HB362 to boost state gasoline taxes for the first time in 17 years — by 4.9 cents per gallon, with provisions to allow automatic increases in the future.
That is expected to provide about $55 million annually now. Braceras said $40 million will go to the long-neglected rural state highways and the rest to improve or replace bridges.
The TRIP report said only 1 percent of bridges on Utah interstates are "structurally deficient," compared with a national average of 3 percent. Also, 17 percent of the Utah bridges are "functionally obsolete," compared to a national average of 18 percent.
The report also said that 44 percent of Utah's urban interstates are considered to be congested, lower than the national average of 55 percent. California has the nation's most congested freeways, at 85 percent, followed by Maryland, at 75 percent.
Fast-growing Utah managed to keep congestion relatively low and the conditions of freeways good while seeing a 30 percent jump in travel on its interstates between 2000 and 2014, the sixth highest leap in the nation. That more than doubled the average increase nationally of 14 percent.
However, Utah freeways have a higher fatality rate than average.
In 2014, that was 0.67 per 100 million vehicle miles traveled, higher than the 0.57 percent average nationally.
The report calls the interstate system the "most critical transportation link in the nation's economy" and the "most ambitious public works project built since the Roman Empire."
It warns that the 47,662-mile system has a backlog in needed maintenance projects of $189 billion, and it estimates that the nation is spending 61 percent of the amount needed annually to keep freeways in good repair and handle future growth.
"Large sections of these once-fabulous roadways are in disrepair," said Bud Wright, executive director of the American Association of State Highway and Transportation Officials. "State departments of transportation are struggling to maintain their portions of this critical national network while demand keeps growing, even when many states have substantially increased their highway funding."
The interstate system was born June 29, 1956, when President Dwight D. Eisenhower signed the Federal-Aid Highway Act into law. It created a federal gasoline tax to help pay 90 percent of the initial construction costs of the freeway system.