With Lake Okeechobee two feet too high and still rising after a month of heavy rain and far-off Tropical Storm Dorian posing a potential but highly uncertain threat, federal engineers on Thursday cranked opened the flood gates on the big lake, spilling tens of billions of gallons of polluted water down rivers on both coasts.
The “maximized” releases are intended to protect public safety, making room for flood waters and easing pressure on the aging, vulnerable Herbert Hoover Dike. The lake remained more than a foot below the danger zone where risks of leaks, erosion or even potentially catastrophic breaches to the massive levee begin to sharply rise. But Dorian or some other future tropical deluge could quickly fill that gap as South Florida enters the peak of the hurricane season.
“It is imperative that we take additional measures to control the rise of the lake to ensure we have enough storage capacity,’’ said Col. Alan Dodd, commander of the U.S. Army Crops of Engineers’ Jacksonville District.
But stepped-up dumping flow spells an expanding environmental disaster for once-rich estuaries on both sides of the state: the Caloosahatchee River on the southwest coast and the St. Lucie River on the southeast. Sprawling black plumes already foul both rivers, a brew produced by local storm runoff but worsened by weeks of steadily increasing dumping of lake water laced with farm and yard nutrients like phosphorous, nitrogen, animal waste and silt.
In the St. Lucie, oysters are shriveling, sea grass beds are withering and waste-related bacteria levels have soared so high that Martin County health authorities have posted signs warning people not to swim in the river. It’s a mess that makes an unrelated algae bloom in Biscayne Bay appear relatively benign.
For frustrated residents, river advocated and environmentalists, it’s dirty water déjà vu.
Both rivers, which double as relief valves for Lake Okeechobee in the region’s flood-control system, have been repeatedly pounded by lake dump over the last few decades. The St. Lucie, about 50 miles north of West Palm Beach, has been hammered hardest — most recently and destructively after the hectic 2004 and 2005 hurricane seasons repeatedly filled Lake Okeechobee.
Jacqui Thurlow-Lippisch, a commissioner for Sewall’s Point, an upscale enclave near the mouth of the St. Lucie inlet, has regularly flown in her husband’s plane to photograph impacts that have spread though much of the Indian River Lagoon complex, from Fort Pierce to south of Stuart.
“This is just ridiculous for black water to be running through our estuaries in front of our homes where we play and fish,’’ said Thurlow-Lippisch. “I am angry at my government and I am part of the government. There is no excuse for this to keep happening.’’
The Corps, which co-manages the lake and regional flood-control system with the South Florida Water Management District, insists the agencies are doing everything they can with an outdated regional drainage system periodically overwhelmed by South Florida’s extreme weather. When it rains like it has so far in July, approaching double the typical amounts in some areas, the lake can rise much faster than the Corps can lower it.
“We really are constrained in terms of where water can go,’’ said Thomas Greco, the Corps’ deputy district commander. “We’re doing our best.’’