As a civil engineer, Om Goel had faith that Chicago's world-famous El, however old, rickety and perennially cash-strapped, was maintained well enough that the trains would at least stay on the tracks.

That was before the subway car the 63-year-old was riding in during a rush-hour commute lurched off the rails, igniting a smoky fire and sending him and 1,000 other passengers scrambling through a dark tunnel.

"My confidence is now absolutely shaken," said Goel, one of more than 150 people injured, six seriously, in that July 2006 accident. "Every time I get on the subway now, I'm thinking, 'Oh my God, I hope it doesn't happen again."'

Industry watchers share his sense of dread.

They say the nation's oldest subways are in dire need of repairs and upgrades to fix everything from decades-old track in Chicago to serious overcrowding in New York, but don't have enough money to keep up.

The National Transportation Safety Board in September blasted Chicago's inspection and maintenance procedures, concluding that the immediate cause of last year's accident was rotted wooden ties and corroded bolt-like fixtures that failed to hold the rails in place.

Investigators said the accident should be a warning to other cities.

"This accident is about the failure to understand and invest in a system of this age that carries thousands and thousands and thousands of people every day," NTSB board member Kitty Higgins said.

Federal, state and local spending on mass transit is around $40 billion a year, and that should be increased by $25 billion to properly repair and upgrade U.S. networks, the research firm Cambridge Systematics has concluded. Others have suggested doubling or tripling what is spent now.

"It's like financial life-support," said Chris Kozub, of the New Jersey-based National Transit Institute. "We keep them alive, but we never give enough to cure what ails them."

Transit officials say problems abound:

—New York City's subway system, the nation's largest, is chronically overcrowded even though the city has spent more than $50 billion since 1982 to rescue its mass-transit network.

"Most riders think the subway's run by an angry, indifferent god," said Gene Russianoff of the Straphangers Campaign, a transit advocacy group. "On some lines, I can't believe how many people are crammed in. It's like a Picasso painting — arms here, legs and shoes there."

For those who recall how bad things used to be in New York, today's system looks good, Russianoff said. For example, the transit agency says a train now breaks down about once every 150,000 miles versus once every 7,000 miles in 1982.

But interest owed on money it borrowed to upgrade the system could saddle the agency with $2 billion in debt by 2010. That means it could be difficult to find money for further improvements, including wholesale repairs needed at about 250 of the city's 468 subway stations, Russianoff said.

—In Boston, about one-third of the Massachusetts Bay Transportation Authority's operating budget goes toward paying interest on a $5 billion debt, the largest of any U.S. transit agency. The agency can afford only to maintain things, not to upgrade them, MBTA General Manager Daniel Grabauskas said.

—In Washington, booming ridership has outstripped piecemeal improvements of the Metro subway, which has struggled to find money to buy enough new trains to ease overcrowding.

As bad as things may be elsewhere, it is hard to imagine they could be worse than in Chicago.

Nearly 25 percent of the Chicago Transit Authority's 242 miles of track — some of it elevated, some of it underground — is so shoddy that in some stretches, trains designed to travel more than 50 mph must plod along at 5 mph — about the pace of a horse at trot. The average rail car is 23 years old, and nearly one-third exceed the 25-year maximum recommended by federal authorities.

In the past two years, there have been at least nine accidents on the El, including fires and minor derailments that led to evacuations.

Now the more than century-old system — a landmark that has served as an instantly recognizable backdrop in such movies as "The Fugitive" and "The Blues Brothers" — threatens to become a liability as the city bids for the 2016 Summer Olympics. Two competing cities, Madrid and Tokyo, have modern rail networks.

Since last year's accident, the CTA says, it has replaced the worst stretches of track and improved inspections but says it still needs more than $4 billion to fix or replace track, bridges, signals and stations, as well as to buy new trains.

City and state lawmakers are discussing a possible regional sales tax or casino gambling to pay for improvements.

Commuters say something must be done.

"Cities can die if the infrastructure does not grow according to the demands of the people. They'll leave," Brittany Berndtson, 23, said recently while waiting at a subway stop.

Robert Dunphy, a researcher at the Washington-based Urban Land Institute, agreed that delays in dealing with the problem could be costly.

"If you don't pay constant attention to them, it doesn't take very long before things go downhill fast," Dunphy said. "And you find yourself in a very bad place."