Dry weather turns Lake Okeechobee from flooding threat to water supply backup

Lake Okeechobee is quickly changing from a flood threat to water supply safety net for South Florida. As Florida enters its dry season, Lake O is in good shape to provide the irrigation water needed by farmers and drinking water should drought conditions become a reality.

As once-swollen Lake Okeechobee drops back to normal, months of draining to protect against flooding now switches to saving lake water to boost South Florida's supplies.

The lake level dropped nearly a foot during November, dipping under 15 feet above sea level Monday.

That's just above the historic average, following months of high-water levels resulting from El Niño-driven rains and the summer storm season.

Now, as Florida's dry season starts to kick in, water managers say the lake is in good shape to both irrigate South Florida's sea of sugar cane and to backstop community drinking water supplies if a drought emerges.

Even at the lake's current steady recession, projections show just a 10 percent chance that the lake level would drop low enough to trigger water shortage concerns before summer rains bring relief, according to the South Florida Water Management District.

Drier weather and the declining water level could also help the environmental health of the lake. Relief from high-water levels should boost water quality and keep from drowning lakeside marshes, helping everything from bass to wading birds.

"Overall it's come through it very well," Audubon Florida scientist Paul Gray said about Lake Okeechobee. He monitors the lake for the environmental group. "We are pretty safe [in case of] severe drought, at least for this dry season."

Before man-made manipulations, Lake Okeechobee's water used to naturally flow south, spilling over its southern shores and replenishing the Everglades.

But decades of draining to allow the spread of development and farming turned Lake Okeechobee into South Florida's massive retention pond. Rainfall that once flowed south now gets held in the lake to avoid flooding.

During South Florida's dry season, canals siphon out lake water to irrigate farmland and restock drinking water well fields.

Lowering the lake had been a priority for most of this year. Rising waters that peaked at 16.4 feet threatened the stability of the lake's dike — a 30-foot-tall, erosion-prone mound of rock, shell and sand that is considered one of the country's dikes most at risk of a breach.

In January, the Army Corps of Engineers started draining billions of gallons of lake water each day east toward Stuart and west toward Fort Myers.

While that draining eased the strain on the lake's 143-mile-long dike, the deluge of lake water and the polluted sediment it carried clouded rivers, damaged coastal fishing grounds and fueled toxic algae blooms that scared away tourists.

As the lake level started to drop, the Army Corps in November stopped the lake draining to the east and has since significantly reduced draining to the west.

While lake draining can hurt coastal waterways, prolonged high water levels in the lake can also pose an environmental risk within the lake.

Rising lake waters submerge more of the marshes rimming the northern and western portions of the lake. That can drown breeding and feeding grounds for fish and wading birds. Those grasses also help water quality by filtering out nutrient-rich pollutants that drain into the lake.

There was a 45 percent decline in that vital lake habitat between August 2015 and August 2016, according to the water management district.

"When they are gone you just have really dirty water," Gray said. "They are really important to ... the sport fishing. That's where the bass live."

Fishing conditions on the lake have been good throughout the year but are improving as the water level declines, according to Mary Ann Martin, owner of a marina in Clewiston.

Lake algae blooms that caused water quality problems over the summer have dissipated, and Hurricane Matthew helped wash away tufts of dead vegetation that had blocked boat access in some areas, Martin said.

"You hear the birds. You see the fish. You see the alligators," Martin said. "This lake is alive and well. It's kicking butt."

State officials and environmental advocates alike bill Everglades restoration as the long-term answer to lake drainage woes.

Taxpayers have already invested more than $3 billion in efforts to store, clean up and send south more of the water now drained out to sea.

The Florida Legislature in the spring is expected to consider Senate President Joe Negron's proposal to build a $2.4 billion, 120-billion-gallon reservoir on farmland south of the lake that could create another lake drainage alternative.

The lake's dike remains in the midst of a slow-moving rehab, expected to last until 2025.

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