Heavy rain Sunday could result in discharges from C-44 Canal to the St. Lucie River

Heavy rains forecast for Sunday have the Army Corps of Engineers alerting the public to the possibility of discharges to the St. Lucie River, and increases to the Caloosahatchee.

The National Oceanic and Atmospheric Administration has forecast a "high degree of certainty" for heavy rain and potential flooding over much of South Florida, according to a news release the Corps issued Friday.

"These decisions must sometimes be made quickly to address rapidly changing conditions in order to protect public health, safety and property along the canals," the release says. 

Areas south of Lake Okeechobee are forecast to get the most rain and severe storms throughout Sunday and into Monday from a low-pressure system that's moving east from the Gulf of Mexico and forecast to stall over the peninsula Saturday night.

"The forecasted rainfall is more than we've seen in a while, and conditions can change quickly in an event like this," Army Corps Col. Andrew Kelly said in the news release. "We want our stakeholders to be aware of these potential conditions which may require action, including a short-term opening of S-80."

S-80 is the St. Lucie Lock and Dam, which releases water from the C-44 Canal, also called the St. Lucie Canal, into the St. Lucie River.

The Army Corps this week reported visible algae blooms at both locks that release lake water east to the St. Lucie River and west to the Caloosahatchee River (W.P. Franklin), the news release says.

"Lake Okeechobee showed moderate bloom potential along the northwest shoreline and light bloom potential for the rest of the lake," the news release says, adding that the Florida Department of Environmental Protection's weekly update from April 24-30 stated the satellite imagery was partially obscured. "The St. Lucie estuary was too obscured for an estimate and the Caloosahatchee River showed no observable bloom activity." 

The National Weather Service has forecast these rainfall amounts (in inches):

0.85: Treasure Coast

1.32: Fort Myers

2.81: West Palm Beach

3.11: Naples

Until the rains come, it will be business as usual for Lake O management.

The lake level was 11.25 feet Friday. That's 0.19 feet less than last week, 0.37 feet less than last month and 0.01 feet more than this time last year.

As of 4 p.m. Friday, the Army Corps was not discharging any lake water to the St. Lucie River, but was continuing its planned seven-day average of 350 million gallons to the Caloosahatchee River, which often needs a freshwater influx this time of year to prevent saltwater intrusion from the Gulf of Mexico. The St. Lucie never needs it.

Lake water can be polluted with fertilizer that feeds algae blooms as well as carry toxic blue-green algae into the river, then the Indian River Lagoon, then the Atlantic beaches.

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