South Florida's decaying bridges

SOUTH FLORIDA - The bridges of South Florida carry tens of thousands of motorists a day -- to home, to work, to play. But the wind and waves that make this paradise are constantly eating away at these aging structures, leaving drivers to ride on cracked concrete and corroded steel.

"What takes the most toll on our bridges is the salt water," said Florida Dept. of Transportation Structural Maintenance Engineer John Danielsen. "Most of our bridges out west will last 75 years, east 50 years."

SPECIAL SECTION: Bridges on the Brink

We went underwater to see for ourselves the condition of some of the most heavily traveled bridges in South Florida and what we found down there is concerning. Concrete that has been ruptured by the expansion of rusting rebar inside.

There are 1,409 bridges in Miami Dade, Broward and Monroe counties.

Records obtained by Local 10 investigates show more than a third of them, 534 bridges, are 50 years or older.

Of those, 333 are considered "Functionally Obsolete." That means one or more components of the structure don't meet current design standards.

Thirty six are classified as "Structurally Deficient," a term used to describe a bridge that needs repairs or replacement within the next 6 years.

"It does not mean the bridge is going to collapse," said FDOT Structural Maintenance Engineer Dennis Fernandez. It doesn't mean the bridge is unsafe. It's only a warning that you need to do some repairs to that bridge."

The Florida Department of Transportation is the state agency in charge of inspecting South Florida's bridges.

It's a comprehensive process -- examining all aspects of a span -- the decking, the columns, the foundation that supports the entire structure.

Each bridge is inspected at least once every two years -- even more frequently if trouble spots are discovered.

We followed inspection crews underwater and in the air as they searched for cracked concrete and corroded steel.  But despite their best efforts to keep our bridges in tip top shape, the environment eventually takes its toll.

"Once the choloride gets into the concrete, you can't get it out," Danielsen said. "The rebar starts rusting. When the rebar starts rusting, it expands and it spalls the concrete."

This week, we're going to show you the worst of the worst -- the most heavily traveled bridges in South Florida labeled structurally deficient by the state. In some cases, you might ask 'Why is this bridge still open?'"

"If we find or feel that a bridge is unsafe, we notify the owner and if the owner doesn't take any action, we will," Fernandez said.

We'll also show you the plan to fix these battered bridges. You'll be surprised to learn how much tax money it takes to keep South Florida drivers safe as they travel on these bridges on the brink.

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