Aging Lake Okeechobee dike

If a Harveylike storm were to come, all eyes would turn to the Herbert Hoover Dike ringing Lake Okeechobee.

Built in the 1930s, experts warned in a 2006 report the aging dike’s condition posed “a grave and imminent danger to the people and the environment of South Florida.” A breach would put 40,000 people who live around the lake at risk, irreversibly damage the Everglades and threaten to contaminate South Florida’s water supply, according to an analysis by engineers.

Since 2000, about $870 million has been spent modernizing the dike, according to the U.S. Army Corps of Engineers. About $830 million is set to be spent on remaining repairs with a target completion date of 2025.

The lake’s current level is about 13.5 feet, but it could rise rapidly in the face of record rains, said John Campbell, a regional spokesman for the U.S. Army Corps of Engineers.

Campbell estimated that each foot of rain falling into the basin north of the lake would cause the lake level to rise 3 to 4 feet. Once the lake level reaches 21 feet — past the record level of 18.77 feet set in 1947 — a breach in one or more locations would be likely, according to the Army Corps of Engineers.

“As the lake level rises, certainly the risk of failure increases,” Campbell said.

No emergency spillway is available for a quick release of Lake Okeechobee water if a storm like Harvey is approaching, Campbell said. The Corps of Engineers can release water from the lake, Thomas MacVicar, a water management consultant but that takes days or weeks to have a significant effect, he said.

Florida Gov. Rick Scott said during a visit to West Palm Beach this week that what happened in Houston shows why dike work needs to be accelerated. He wants improvements to be completed by 2022 — three years ahead of schedule — and pushed for $50 million in state funding to be allocated to jump-start projects.

Robert Molleda, a meteorologist for the National Weather Service’s Miami office, said predicting exactly how 50 inches of rain from a single storm would affect South Florida is difficult because it’s never happened before.

Given that storms dropping half that amount of rain have crippled the region, stranding drivers and marooning neighborhoods, it would definitely be a catastrophic disaster, he said.

“It is so incredibly rare to see so much rainfall over an area,” Molleda said. “It would be an extremely rare event, but you can’t say it’s impossible.”

Staff researcher Barbara Hijeck contributed to this report. Information from The Associated Press and WPEC-CBS12 also was used.

sswisher@sunsentinel.com, 561-243-6634 or @SkylerSwisher