The truth about Iowa’s roads

Iowa HighwaysBy Bob Eschliman


Iowa has more than 112,000 road miles and nearly 25,000 bridges, ranking our state 10th and fourth, respectively, in those categories. And, with the intersection of two of the nation’s busiest Interstate highways, I-35 and I-80, we see a large volume of traffic, about 31.5 billion vehicle-miles in 2013.

Like all states, we pay for the upkeep on those roads and bridges through a wide array of funding mechanisms involving fees, excise taxes, and federal highway funding. But, unlike a majority of states in the U.S., Iowa does not have any toll roads.

According to the Iowa Department of Transportation, the state spends roughly $1.4 billion a year on construction and upkeep of Iowa’s highways, roads, streets, and bridges. The vast majority of that, about $1 billion, comes from the Road Use Tax Fund.

FY 2015 Transportation FundingThe chart at right (click to see in full size) shows how the money flows in and out of the RUTF, but in simpler terms, here’s how the money flows in and out of the fund.

The largest portion of RUTF revenue is in the form of motor fuel excise taxes; those account for about $400 million a year in revenue. Registration fees on vehicles contribute about $330 million, while vehicle use taxes – essentially a one-time “sales tax” (vehicle purchases are exempt from state sales tax, which goes to the General Fund) on the purchase of new vehicles – contribute another $210 million.

Nearly half of the money coming out of the RUTF – 47.5 percent of it – goes to the Primary Road System, which includes the Interstate highways, the components of the National Highway and Primary systems in Iowa, and the state highways. Some roads have multiple designations, which causes about 13,000 road-miles of overlap.

The Primary Road System accounts for 23,375 road-miles (18.59 percent) and 3,292 bridges (13.32 percent). About 61 percent of all vehicle-miles in Iowa travel on this part of Iowa’s road system.

The counties receive the next largest portion of the money coming out of the RUTF. The county roads receive 24.5 percent of it, while “Farm to Market” roads receive 8 percent. These account for 89,455 road-miles (71.12 percent) and 20,267 bridges (82.04 percent), but only 17 percent of vehicle-miles.

The cities receive the remaining 20 percent of the money coming out of the RUTF. Combined, Iowa’s cities have 12,967 road-miles (10.31 percent) and 1,146 bridges (4.64 percent), while accounting for about 22 percent of the state’s vehicle-miles.

Cities and, to a lesser extent, counties, have the ability to use property taxation to pay for road construction and improvements. This can be done either through general obligation bonding, or through direct assessments to adjacent property owners who typically benefit most.


Breaking Down the Primary Road System

47.5% of $1 billion is $475 million.

$475 million divided by 23,375 road-miles is $23,321 per road-mile.

61% of 31,542,000,000 vehicle-miles is 19,240,620,000 vehicle-miles.

$475 million divided by 19,240,620,000 vehicle-miles is 2.5 cents per vehicle-mile.


Breaking Down the County Road System

32.5% (22.5% + 8%) of $1 billion is $325 million.

$325 million divided by 89,455 road-miles is $3,633 per road-mile.

17% of 31,542,000,000 vehicle-miles is 5,362,140,000 vehicle-miles.

$325 million divided by 5,362,140,000 vehicle-miles is 6 cents per vehicle-mile.


Breaking Down the Municipal Road System

20% of $1 billion is $200 million.

$200 million divided by 12,967 road-miles is $15,424 per road-mile.

22% of 31,542,000,000 vehicle-miles is 6,939,240,000 vehicle-miles.

$200 million divided by 6,939,240,000 vehicle-miles is 2.9 cents per vehicle-mile.