The water level of Lake Okeechobee rose above 15.5 feet Monday — a seldom-reached benchmark that officially raises the Army Corps of Engineer’s level of concern over the aging Herbert Hoover Dike that protects local communities from flooding.
The corps sought to allay public concern, however.
“The lake reaching 15.5 feet only triggers the start of weekly inspections at the dike, in accordance with our surveillance plan,” said Jenn Miller, a public affairs specialist for the corps.
The corps, which owns the dike that girds Lake Okeechobee, is responsible for maintaining the water at a safe level. It does so by opening and closing pumps, gates and locks around the 730 square-mile lake. “The inspections started today and currently there are no areas of concern.”
Since 2008, when 15.5 feet became the tipping point for concern, the massive lake had only risen above that level once. That occurred in October 2012, six weeks after Tropical Storm Isaac dumped as much as a foot of rain throughout the region. The lake level was at 12.48 before that storm. By the time the waters stopped rising, the lake had risen 3.5 feet, to 15.92 feet.
That the lake has risen so high, so early in the hurricane season — the season doesn’t end until Nov. 30 — concerns Palm Beach County Administrator Bob Weisman.
“It does create a problem for us in the event of a hurricane storm event,” Weisman said. “As the elevation gets above 15, there is a higher risk of dike failure,” he said.
“Clearly the higher the lake elevations, the more stress it adds to those in government to protect the public out there and make decisions about what is right and wrong,” he added. “An evacuation is traumatic. It is a horrible thing to have to contemplate doing.”
The good news is that over the past few years the corps has reinforced a 21-mile stretch of the dike between Pahokee and Clewiston and it plans to replace culverts and other structures that have weakened since the dike was built in the 1930s. The corps has also stockpiled rocks and boulders near the lake in the event of a breach and an evacuation plan is in place.
The corps manages the lake according to a “regulation schedule,” designed to balance a variety of environmental factors including current lake level, time of the year, needs of the estuaries and the Everglades, weather forecasts and the integrity of the dike.
The schedule in use today was adopted in 2008. Earlier schedules allowed water to rise above levels considered safe for the dike and to levels that damage the shallow lake’s plant and animal communities.
Under the new schedule, the corps is allowed to release water from the lake before it rises above 15 feet. When the corps releases water from the lake, it flows into the Caloosahatchee River to the west and the St. Lucie estuary to the east — brackish estuaries that are already stressed by fresh water and pollution from local stormwater runoff.
Because water flows into the lake twice as fast as it can be released, the corps has been releasing water from the lake for over a month. Last week the corps upped the amount of water it was releasing because rainfall that has been 70 percent above average. Environmentalists say without relief soon, much of the oyster population will die, along with sea grasses and other plants and animals that cannot tolerate fresh water.
The South Florida Water Management District, which is responsible for flood control throughout the region, offers advice and data to the corps about the lake’s condition. It’s not just the current level of the lake that concerns water managers.
“Our concern is not limited to the lake,” said Tommy Strowd, the district’s Assistant Executive Director for Operations, Maintenance and Construction. Because the system is already saturated, retention ponds, wetlands, canals and even the soil cannot absorb any more water. “Right now, it’s almost as though everything is paved. Pretty much the whole system is full.”