Idaho faces a nearly half-billion-dollar annual shortfall to maintain and improve its roadways, with no plan in place to generate the needed revenue. The Gem State is not alone in its transportation funding crisis.

Oil-rich Texas has built more highways and bridges than any other state, but over the next two decades it will fall $170 billion short of what it needs to keep the sprawling network in good repair.

In California, 60 percent of the state’s roads and a quarter of its bridges need to be repaired or replaced, at a cost of $70 billion over a decade, some $52 billion more than the available funds.

North Carolina will confront a $32 billion road maintenance shortfall over the next 30 years.

America’s highway system, once a symbol of freedom and mobility envied the world over, is crumbling physically and financially, the potentially disastrous consequence of a politically driven road-building binge.

President Barack Obama, state transportation officials, civil engineers, road builders and business groups all say that the country needs to invest trillions of dollars in its infrastructure, yet there’s little consensus on how to finance it or what the most pressing needs are.

The Congressional Budget Office estimates that the country needs $14 billion in additional federal funds each year just to maintain highways and $50 billion more to improve them.

Federal government analysts, taxpayer advocates and transportation experts have warned for at least a decade that states were spending too much on building highways and too little on fixing them.

“We’ve engaged in a dangerous game of deferred maintenance,” said Brian Taylor, a professor of urban planning and the director of the Institute of Transportation Studies at UCLA.

CRAZY COSTS

Five years after an interstate highway bridge collapsed in Minnesota, killing 13 people and injuring 145, the country still has a bridge repair backlog of $65 billion, according to the Federal Highway Administration. Of Idaho’s 1,796 state-owned bridges, 299 of them are in need of fixing at an estimated cost of $1 billion.

At a time when Congress is proposing significant budget cuts and tax increases have little support, states are canceling or scaling back highway projects. They’re looking for private partners to help finance construction and are coming up short.

When Idaho Transportation Department Director Brian Ness took the helm in 2010, “I promised ITD would not request additional revenue until I could assure every penny was being spent as efficiently and effectively as possible,” he said.

Ness said he has focused on reinvesting savings into maintaining roads and bridges.

“It is estimated that $1 spent on repairs while a road is still in good condition can prevent costs of $6 to $14 to rebuild the same road once it has deteriorated,” he said.

But the agency cannot meet long-term maintenance needs.

“To maintain our roads, highways and bridges, and to propel Idaho’s economy, we will need to increase our investment in transportation,” Ness said. “We talk a lot about not wanting to pass the national debt or state debt to our children. By deferring highway maintenance we can do at lower costs now, we are essentially passing on a debt to our children.”

Over the past four months, McClatchy traced the extent and causes of yet another financial crisis that’s developed below the radar of most Americans.

A review of government reports, an analysis of thousands of state and federal campaign donations, and interviews with dozens of current and former elected officials, watchdogs and transportation officials showed that there were a lot of hands on the wheel as the system veered off course.

For example:

- The oldest parts of the interstate highway system have reached the end of their life cycle, including thousands of bridges dating to the 1960s, a threat to public safety and commerce.

- The federal gasoline tax no longer covers the country’s annual highway spending, but few leaders in Washington are willing to take on the political risk of increasing it, which forces states to borrow more money, raise tolls or ask their residents to approve new taxes.

- Despite a ban on members of Congress “earmarking,” or skimming money for pet projects back home, lawmakers and the special interests that bankroll their campaigns still exert outsized influence on where federal highway funding goes.

- The Department of Transportation long ago ceded control over most highway decisions to the states without well-defined national goals, leaving a large portion of federal money up for grabs for those with the most clout.

Like the Roman Empire, “civilizations fall because they don’t maintain their infrastructure,” said David Burwell, the director of the climate and energy program at the Carnegie Endowment for International Peace in Washington.

“Everybody likes to build things, but nobody likes to maintain them,” he said.

FALLING APART

When Al Biehler became Pennsylvania’s transportation secretary a decade ago, he found that the state had been spending more on expanding its highway system than it had on keeping it in good repair.

“If you don’t put money into fixing things,” Biehler said, “there will be more things to fix.”

So he did the unthinkable: He put the brakes on some projects, risking the wrath of highway contractors and state lawmakers.

“Projects that we knocked off the program, some of them weren’t terrible projects,” he said. “I just felt we couldn’t afford them.”

The Federal Highway Administration doesn’t require states to put money into repairing roads before building new ones.

Pennsylvania was spending about as much of its federal funding on expansion as it was on maintenance in 2004, according to federal data reviewed by McClatchy. By 2011, the state was spending about four times as much on repairs, and it was still struggling to keep up.

The Pennsylvania State Transportation Advisory Committee reported in 2010 that the state needed an additional $2.1 billion a year to properly maintain its highways and bridges.

“More than half of our bridges have reached their intended life-span date,” said Barry LePatner, a New York construction lawyer who’s cataloged nearly 8,000 of the nation’s most troublesome spans. “Without maintenance money, cost of repair equals cost of replacement after a certain period of time.”

Some budget watchdogs were encouraged that the most recent federal transportation bill, MAP-21, which Congress approved last summer, pushes states to develop performance standards for federal highway spending that result in the greatest improvement to roads and bridges.

But it’s too soon to know whether the measures will have any impact. Meanwhile, states face tough choices. Emil Frankel, who was assistant secretary for transportation policy under President George W. Bush, said the country needs priorities.

“Thirty years ago, ‘like it’ might have been good enough,” said Frankel, who’s now a visiting scholar at the Bipartisan Policy Center, a research center in Washington. “ ‘We’ll do it because we like it.’ We can’t afford to do that anymore.”

RUNNING ON EMPTY

It’s been 20 years since Congress raised the gasoline tax. The 18.4-cents-a-gallon tax has lost a third of its buying power to inflation and rising construction costs.

In addition to the federal gas tax, Idahoans also pay a 25-cent state gas tax, which has not increased since 1996.

The federal tax feeds the Highway Trust Fund, which long has paid for a portion of highway construction and repairs in all 50 states. About 50 percent of the state money Idaho spends on transportation dollars comes from federal sources.

The fund used to carry a surplus, but lawmakers have bailed it out since 2008 by tapping the Treasury for about $50 billion.

“That can’t continue indefinitely,” said John Horsley, who retired in January as the executive director of the American Association of State Highway and Transportation Officials.

Simply increasing the gas tax might not be the best option. Americans have been driving less since 2007, partly because of the recession and higher gas prices and partly because of a generational shift away from car ownership.

Horsley proposes replacing the per-gallon gasoline tax with a percentage-based sales tax. Sen. Barbara Boxer, D-Calif., the chairwoman of the Senate committee that drafts transportation legislation, has said she’ll consider the idea, along with other alternatives, including a carbon tax and a tax based on the number of miles driven.

States have taken on more debt, and some have about as much as they can support. According to Federal Highway Administration data, all states carried a combined $56 billion in road bond debt at the end of 1995, in current dollars. By 2010, they owed $154 billion. Idaho had zero road bond debt in 2005; today it owes $775.5 million.

State and local governments have asked voters to approve sales tax increases, and about two-thirds of such measures pass.

In a novel approach, Indiana and Illinois leased toll roads in exchange for money they used to bankroll highway projects. Virginia and California have sought private partners to build bridges and highways.

PAVED BY POLITICS

Highway supporters frequently characterize their foes as anti-road, anti-jobs or anti-progress. However, even the most ardent highway proponents agree privately on what they’re reluctant to admit publicly: Some projects are just better.

In some state plans, it’s hard to tell the difference. And in the absence of clear national priorities, politics drives the funding.

For years, some states complained that they were “donors” who got back less than a dollar in federal highway funding for every dollar in gasoline taxes they contributed. Congress fixed that by baking in extra funding. The formula now favors small states or those with low population densities and shortchanges more populous states, said Donna Cooper, a senior fellow at the liberal Center for American Progress in Washington.

“We just created a nightmare for ourselves by creating a system that sends money to places with the least need,” she said.

According to the Government Accountability Office, Idaho gets back $1.70 for every dollar it sends to Washington. Alaska gets back $5; Texas a dollar.

Idaho Statesman reporter Cynthia Sewell contributed to this report.