The goods news is that the corps expects the lake will only rise about a foot in the next month, much less than originally feared.

In the weeks ahead, storm-water runoff from Hurricane Dorian will be dumped from Lake Okeechobee into the beleaguered St. Lucie Estuary and Caloosatchee River as the Army Corps of Engineers works to maintain safe and healthy water levels in the lake, according to Corps spokesman Jim Yokum.


Hurricane Dorian: 6 inches of rain, 7-foot storm surge possible, water managers say


The goods news is that the Corps expects the lake will only rise about a foot in the next month — far less than the 3.5 feet initially predicted when it looked like a stronger, wetter Dorian would wallop Palm Beach County.


The Corps prefers to keep the lake between 12.5 feet and 15.5 feet. The highest water level in the lake was the 18.7 feet recorded in 1947.


Stormwater runoff flows into the lake six times faster than it can be released. The more water in the lake, the greater pressure on the wall of the 43-mile earthen dike, rated one of the most likely to fail in the United States. When lake levels reach 18.6 feet, the dike is at risk of breaching.


The water level on Wednesday stood at 13.9 feet.


For now, the Corps is not releasing water from the lake into the St. Lucie or Caloosahatchee estuaries. However, runoff from local roads, yards and fields is currently being released in the St. Lucie estuary.


The Corps has not announced when it will begin the lake releases but will consult with the South Florida Water Management District and other stakeholders before opening gates, Yokum said.


The discharges dilute salinity levels in the brackish estuaries and can seed toxic algae blooms. Fresh water from the Lake Okeechobee can also kill seagrasses, oysters and habitat essential for other wildlife in the estuary.


While recent efforts to protect the St. Lucie and Caloosahatchee estuaries have focused on building water storage south of Lake Okeechobee to reduce harmful freshwater discharges, a more sweeping reevaluation of lake levels, water-supply needs and monitoring of agricultural and urban runoff north of the lake began this year.


Cstapleton@pbpost.com


@StapletonPBP