BOSTON -- Meg Garvey dreads having to drive under bridges on her commute to work

"I hate it. I hate it. There are a lot of bridges. I'm looking up every time," she said.

You can't blame her. In September, Garvey was driving under the Cambridge Street bridge in Allston when chunks of concrete fell from the ceiling and crashed through her sunroof. Miraculously, the Marlborough nurse wasn't hurt. She told Team 5 Investigates Kelley Tuthill she could have been killed.

"Oh easily, easily, because there was a hole in the passenger head rest from where the rock hit," Garvey said.

Team 5 Investigates has learned the state has known this bridge was a problem for the past two years. It's one of 550 across the state labeled structurally deficient, meaning at least one part of the bridge needs to be repaired or replaced.

Frank Tramontozzi is the chief engineer for the Massachusetts Department of Transportation. Team 5 asked him why the bridge's last inspection before the accident did not show a problem.

"That's not unusual because problems develop over time," Tramontozzi said.

What is unusual is that the state's temporary fix, called shielding, failed that day. Tramontozzi said the concrete fell in a section that had no reinforcement.

"It was an area that didn't have a problem when it was last inspected," he said.

Team 5 Investigates has learned nearly 200 Bay State bridges have some kind of protective shield on them trying to make sure pieces of concrete don't fall on the drivers below. That shielding can be seen on bridges in Natick and Westborough. Netting and planks are in place until a permanent fix can be completed.

Garvey said it's not enough.

"I don't know what the answer is, but I do know the Band Aids don't work."

Tramontozzi said his department is merely trying to catch up after years of neglect.

"A Band Aid is a good word to use, because you are not correcting the problem, you are just covering it up."

Team 5 examined the state's list and found one commuter rail bridge labeled structurally deficient since 1989. At least six others date back to 2003. A Mass Pike bridge near the CSX tracks in Boston carries almost 64,000 people daily and has a poor rating by the state. But there is no repair date on the calendar.

"The problem will not go away, we have to invest in our infrastructure to make it in good condition," Tramontozzi said.

A $3 billion, eight-year accelerated bridge program began last year to fast track repairs, like the Hancock bridge in Quincy. But Team Five has learned some won't be finished for 4, 5, even 6 years! And because the program also strives to maintain bridges before they fall apart, more than 300 structurally deficient bridges didn't even make the list.

"It's not specifically those bridges, those numbers that are being actually even touched under this program," Tramontozzi said.

As for the Cambridge Street bridge, it won't be repaired until at least 2012.

"It's all about money and the lack of it so that we can't fix it right now so we are just going to put the Band Aids up and hope that nothing goes wrong," Garvey said. "Well I was lucky but what about the next person?"