State of disrepair: Colorado's transportation system is crumbling, and a projected price tag of $1.5 billion has few willing to hit the political pavement.

• Author: Best, Allen

THE INTERSTATE 70 VIADUCT IN DENVER OPENED IN 1964. THAT YEAR LYNDON JOHNSON DENOUNCED PRESIDENTIAL OPPONENT BARRY GOLDWATER AT THE NEARBY DENVER COLISEUM, AND THE BEATLES PLAYED RED ROCKS. TICKETS FOR THE SHOW COST $6.50, AND GAS WAS RUNNING 20 TO 30 CENTS A GALLON.

Traffic volumes, like gas prices, have increased dramatically since then. That highway section east of Interstate 25, originally used by 31,000 vehicles daily and since widened, now accommodates 140,000 vehicles daily. But more startling yet is the escalated cost of building highways. The entire 2.6-mile section between the I-25 "mousetrap" interchange and Colorado Boulevard cost only $12.5 million to construct.

But the viaduct has become like an old car, says Mark Leonard, the state bridge engineer for the Colorado Department of Transportation. It's still safe, but to keep it that way you have to keep plugging in money: a new transmission, then the wheel bearings, and maybe even the engine.

Just to replace the bumpy, accident-prone 1.1-mile segment between the Coliseum and Colorado Boulevard would cost $800 million. That's four-fifths of the annual state budget for building, repairing and sweeping snow off all the state's highways.

The I-70 viaduct in Denver may be the most egregious example of Colorado's aging transportation infrastructure, but it's hardly alone. Interstate 25 northward past Longmont, Loveland and Fort Collins churns bumper-to-bumper traffic at 80 mph on asphalt Band-Aids. Narrow ribbons of highway between Leadville and Buena Vista and between Haxtun and Wray have shoulders too narrow to accommodate motorists fixing flat tires. The country road that weaves along Piceance Creek, built to handle tractors, pickups and the occasional cattle truck, is now pounded daily by heavy trucks drawn to one of the nation's most active gas-and-oil fields.

This aging infrastructure, left unattended, will spur greater congestion. Drivers in 2015 can expect to spend twice as long stewing in traffic. And they should also expect to spend twice as much time--40 minutes of any given hour--on rough roads, at the expense of tires and vehicle maintenance.

Deteriorating and clogging highways also create a fundamental business problem for Colorado. Doug Aken of Grand Junction, a co-chair of a blue-ribbon panel appointed last year by Gov. Bill Ritter to study Colorado's transportation, is a former banker. Often in his work he met with people interested in expanding their businesses within Colorado or relocating to the state. Transportation, he says, was foremost in their thinking.

"The last thing anybody wants is to get their business situated in an area where we have gridlock, and people can't move goods and services efficiently," Aken says. "At the end of the day, that's what it's all about. That's why this is a long-term issue the business community needs to be concerned about."

Roads are holding up reasonably well now. That will not last, advocates for change say.

"The quality of our roadways in a short number of years will go from B or C level to F," says Tamra Ward, senior vice president of public affairs for the Denver Metro Chamber of Commerce.

The central problem, say Ward and others involved in the governor's ad hoc transportation planning, is lack of investment and the result of relying on a fuel tax that is no longer adequate. Task force members want giant increases in existing taxes and also new taxes in the short term, but recommend long-term consideration of a new user-based tax mechanism.

But many transportation experts also see need for another paradigm shift: State government should invest in mass transit. Looking toward 2030...