Florida levee protecting 40,000 people grows weaker each day

Okeechobee, Florida -- Drive down US-441, and you'll run right into it. A grass-covered wall that stretches as far as you can see in both directions.

It's the levee the wraps around Lake Okeechobee -- that huge lake in the middle of Florida. Altogether, the levee is 143 miles long. And the protection it gives could give way in a massive hurricane.

Peace comes with a price

For a lifetime, living near the waters of Lake Okeechobee has brought peace to the minds of Darrell and Shawna Bray. It's a peace that will last another lifetime with little Gavin, their one-year-old son.

The whole family met along the edge of the lake for a lunch break Wednesday. "That's the only reason that we really stayed here," Darrell said, looking out at the marshy shore of "Lake O". "A lot of our family moved away, but we stayed here because of the lake."

But they know that this peace comes with a price: the risk, however slim, of disaster.

Levee built after deadly hurricane

An unnamed hurricane in 1928 sent the lake's water surging through nearby towns, killing more than 1,800 people. Determined to control any future flooding, the government ringed the entire lake with a 20-foot-high earth wall. That levee, the Hoover Dike, still circles the lake today. And it still winds its way into nearly every one of Michael Faulkner's hurricane plans.

"A lot of the area around the dike is low enough that if the dike was not there, it would end up underwater," said Faulkner, the head of emergency management for Okeechobee County. He knows better than most that the long earth wall and the system that controls the level of the lake strike a delicate balance. It's that balance alone that protects 40,000 people from devastating floods.

Levee holds back one trillion gallons of water

The Hitchiti Indian phrase "oki chobi" literally means "big water". That pretty well describes Lake Okeechobee, the largest lake in the U.S. south of Lake Michigan. But if you've never been there, you probably don't realize that it's entirely surrounded by a 143-mile-long levee. And in a monster hurricane, if parts of the levee were to give way, the word "big" wouldn't be nearly enough to describe the disaster.

"If there's a section that fails, there's gonna be a significant amount of water that comes out of the lake and runs into whatever area that it happens to be effecting," Faulkner said. "We're lucky that in Okeechobee that we've got a fantastic section of dike that's really well-maintained." Army Corps of Engineers teams say the northern parts of the dike are in excellent shape.

Southern walls are weakening

But recent studies have shown that some southern sections of the wall are weakening. More than seven decades of reinforcement haven't been enough.

Tropical Storm Fay added three feet of water to the lake faster than any time on record. The Army Corps of Engineers has begun a $300 million repair project to reinforce the southern reaches of the dike, but some researchers feel that regardless of those improvements, rain from a string of storms like Fay would be enough to rip open the barrier.

Even in her most peaceful moments, that's a reality Shawna Bray can never truly forget. "It is a worry. 'Cause I don't want Okeechobee to be like New Orleans, because that was -- that was terrible," she said.

Starting Thursday, engineers were scheduled to spend about a week lowering the level of the lake through rivers and canals. That will make room for more rain and take some pressure off of the dike, especially if another tropical system moves through.

Study of most vulnerable areas in America

A study ranked Lake Okeechobee as the second-most vulnerable place in America to a hurricane strike. Here's the top ten list from the International Hurricane Research Center:

1. New Orleans, Louisiana
2. Lake Okeechobee
3. The Florida Keys
4. Coastal Mississippi
5. Miami/Ft. Lauderdale
6. Galveston/Houston, Texas
7. Cape Hatteras, North Carolina
8. Eastern Long Island, New York
9. Wilmington, North Carolina
10. Tampa/St. Petersburg

Click here for a Google Map of all 10 locations.

The list combines physical worries, like the risk of storm surge and flooding, along with socioeconomic issues, like the populations in the areas and how prepared those areas have been in the past.