Obstacles Ahead: As roads and bridges deteriorate and federal funding stagnates, states get creative with new revenue streams.

• Author: Sminkle, Douglas

State lawmakers perennially hope for a massive infusion of federal transportation funding. Rut this year, just as certainly as the cherry blossoms along the National Mall fade each April, Congress and the Trump administration again failed to come to consensus on an infrastructure deal.

The federal government sends states more than $45 billion annually to help construct and maintain our nation's roadways. But that hasn't been enough. The federal-aid highway program and several competitive grant programs are guided by the FAST Act of 2015, which will expire in less than a year. Its reauthorization is anything but assured.

America's roads, bridges and transit systems are in poor shape, threatening safety, lowering productivity and increasing long-term costs. There are more than 47,000 structurally deficient bridges in the U.S., and roads and transit arc in even worse shape, according to the American Society of Civil Engineers and the American Road and Transportation Builders Association.

The federal gas tax of 18.4 cents per gallon has not been increased since 1993, and several factors including fuel efficiency, an increase in the number of electric vehicles and the rise of mobility services continue to weaken the gas tax system that has served the nation for 100 years.

Meanwhile, construction and labor expenses continue to rise because of higher material costs and a tight labor market. Construction costs are projected to increase 185.7% by 2030, according to the Institute on Taxation and Economic Policy.

All this has forced states to be creative in finding new ways to firm up the long-term solvency of transportation revenue and ensure safe, efficient infrastructure for all.

Refining the Gas Tax

Since 2013, 30 states and the District of Columbia have increased their gas tax. This year, for example, Alabama approved a 10-cent increase over three years, and Illinois passed a 19-cent increase that began in July. Twenty-two states have linked their gas taxes to inflation, creating variable-rate taxes. Georgia, for example, linked its gas tax to construction costs and the average miles per gallon of new vehicles in the state.

Tapping Into Tolling

Federal law generally prohibits states from tolling existing federal-aid highways and interstates. A few Federal Highway Administration programs, however, allow states to apply for approval in certain circumstances. The Interstate System Reconstruction and Rehabilitation Pilot Program, for example, allows...