By Andy Reid, Sun Sentinel 


E
fforts to drain Lake Okeechobee after the deluge of Hurricane Matthew could lead to more algae blooms and other pollution problems in coastal communities.

Water draining in after Matthew raised the lake to its highest point since February — increasing the strain on the troubled dike that keeps the lake from flooding South Florida

As a result, the Army Corps of Engineers on Friday ratcheted up its draining of lake water to the east and west coasts.

The 30-foot-tall mound of rock, shell and sand surrounding the lake was built in the 1930s and is considered one of the country's most at risk of failing.

"The community is very much aware that the lake is rising and they are asking questions," said Tammy Jackson-Moore, deputy city manager of the lakeside town of Pahokee. "They have this vision in their heads about New Orleans. Will we be the next New Orleans?"

But lowering the lake by dumping polluted lake water east into the St. Lucie River and west in the Caloosahatchee River can fuel toxic algae blooms and cause other environmental harm in waterways near Stuart and Fort Myers.

The Army Corps since January has been draining billions of gallons of water each day to the east and west.

After a previous spike in lake draining, bright-green, foul-smelling algae in July coated waterways near Stuart —making waterways unsafe for fishing and swimming and scaring away tourists.

Aside from the algae blooms, the influx of sediment-laden, freshwater from the lake into the normally clear and salty estuaries can kill sea grass and oyster beds that are spawning grounds for game fish and other marine life.

The new influx of "dark, blackened water" draining east from Lake Okeechobee has already spread across the delicate St. Lucie estuary, said Deborah Drum, Martin County's ecosystem manager.

"We saw an incredible amount of water coming in," Drum said. "It's an added insult ... to the health of the area."

In the wake of the storm, water draining south from Central Florida boosted the lake to 16.15 feet above sea level on Saturday.

By Monday, the increased draining of lake water out to sea and a decline in Matthew's leftover water flows dropped the lake back to 16.04 feet.

That's still outside the peak range of 12.5 to 15.5 feet targeted to avoid overwhelming the troubled dike relied on to protect South Florida from flooding.

Post-storm inspections of the lake's 143-mile-long dike didn't find any signs of increased erosion or other indications of a potential breach, according to the Army Corps of Engineers, which controls lake draining and oversees the dike.

Declining lake levels on Monday prompted the Army Corps to scale back the maximum lake draining, but to continue discharging about 60 percent more lake water to the east and west combined than before the storm.

That means draining as much as 6 billion gallons of lake water total each day to the east and west – enough to fill about 9,000 Olympic-size swimming pools.

"With drier weather in the forecast over the coming days in the area, we believe the immediate threat of a large rise in the lake stage has passed," Candida Bronson, acting operations chief for Army Corps in Florida, said Monday. "However, we will continue to monitor and adjust as necessary."

The Army Corps hasn't determined how long the latest round of lake draining will last.

The lake's dike is in the midst of a costly rehab expected to take until 2025.

abreid@sunsentinel.com, 561-228-5504 or Twitter@abreidnews