The day of President Obama’s inauguration was a record breaker for Washington’s Metro transit system: 1.5 million passengers swarmed aboard its buses and trains.

Days such as the one that nearly overwhelmed the system might one day become routine as projected population growth taxes the regional transportation network.

The grim prospect of a transit agency already burdened with a system that has deteriorated after decades of deferred maintenance and yet will face significant new demand was served up Friday as a microcosm of the nation’s dilemma.

The U.S. population is forecast to grow by 100 million — a 30 percent increase — before the middle of the 21st century. And right now a nationwide transportation system built in the middle of the 20th century is falling apart.

There isn’t enough money to arrest its decline, and the public is largely oblivious to the need.

That was the general consensus Friday at a transportation conference that heard from Transportation Secretary Ray LaHood; House Transportation Committee Chairman John L. Mica (R-Fla.) and his predecessor as chairman, former representative James L. Oberstar (D-Minn.); and a dozen other experts.

“Why haven’t we invested?” said Alan Pisarski, a transportation consultant. “We haven’t made a credible case to the American people.”

The problem is twofold. Although complaints about traffic congestion are commonplace, to the average consumer the transportation system appears to be working reasonably well. And, said several speakers at the conference hosted by Washington Post Live, the amount of money needed to restore and expand it is so enormous that few taxpayers can relate.

“All of the numbers are so gargantuan large that they’re useless when you’re trying to communicate with the public,” said Roy Kienitz, undersecretary for policy at the Department of Transportation.

The American Society of Civil Engineers has estimated that an investment of $1.7 trillion is needed between now and 2020 to rebuild roads, bridges, water lines, sewage systems and dams that
are reaching the ends of their planned life cycles. The Urban Institute puts the price tag at $2 trillion.

Last year, a report by 80 experts led by former transportation secretaries Norman Y. Mineta and Samuel K. Skinner called for an annual investment of $262 billion.

Fail to invest now, and the cost will increase later. Already, the civil engineers said, infrastructure deficiencies add $97 billion a year to the cost of operating vehicles and result in travel delays that cost $32 billion.

“The politicians have been ignoring this data,” said Peter Ruane, president of the American Road and Transportation Builders Association . “This is negligence at the national level.”

He said the discussion over meeting infrastructure needs had been “reduced to a cartoon, a caricature,” in the political debate. “It looks like Congress is going to do the right thing,” he said. “Will they give us the right amount of resources? Right now, it doesn’t look like it.”

As Congress grapples with taming a massive deficit, just keeping transportation funding at current levels has been heralded as a triumph. Though neither house has made public a written proposal, the House has talked of allocating roughly $45 billion a year, while the Senate number is about $54 billion.

Given the gap between estimated need and available cash, there is a bipartisan push to get some form of long-term funding bill through Congress. That, everyone agrees, at least will allow states to tackle major projects that cannot be launched without funding certainty.

But if the nation is going to be saved from a deepening infrastructure crisis, the next steps require finding billions in new revenues, streamlining the project approval process and developing private-public schemes to rebuild and expand highway and transit systems, the panelists said.

Without that, the United States will not remain competitive with other countries.

“We are in a crisis,” said Metro’s general manager, Richard Sarles. “After ribbons are cut, systems are ignored and decay sets in. There’s finally recognition we’ve got to find a good level of funding to resolve it.”

Metro has a six-year plan to spend $5 billion on capital improvements to the decaying system. But it has constant infrastructure problems. Even as the conference was going on, Metro officials were advising passengers to avoid the Red Line in Friday morning’s rush hour because of a track fire that caused the Union Station stop to be temporarily closed for more than an hour.

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