PALM BEACH, Fla.—Six weeks after Tropical Storm Isaac drenched the region with record rainfall, the storm continues to set records — good and bad.
Fishermen and the stores, restaurants and hotels that cater to them on Lake Okeechobee are reporting record catches and business. Meanwhile, on the coast, environmentalists are reporting widespread destruction of oyster beds and sea grasses because of prolonged exposure to fresh water from the storm — much dumped from the lake.
“It’s just devastating,” said Mark Perry, executive director of the Florida Oceanographic Society in Stuart.
For decades, the group has conducted oyster research and restoration efforts, hoping to re-establish populations that have declined by more than 75 percent in the last 60 years in the St. Lucie and Loxahatchee rivers. One adult oyster can filter as much as 50 gallons a day of water polluted with nutrients, algae, bacteria, sediments and other toxins.
“You go out and look and you just want to cry,” Perry said.
But in Clewiston, at the south end of Lake Okeechobee, anglers and business owners are smiling.
“Isaac really kicked a field goal,” said Mary Ann Martin, owner of Roland and Mary Ann Martin’s Marina in Clewiston.
Communities around the 730-square-mile lake were especially hard hit during the 2011 drought, when lake levels were so low that cracked lake bottom replaced water at many docks and marinas. Now it’s the opposite: the water level in the lake has risen nearly 4 feet since Isaac stalled over the region on Aug. 26-27.
“Maybe there is too much water, but I’m not complaining,” Martin said.
Balancing the chemistry and water level in Lake Okeechobee and two of the largest rivers that flow from it — the St. Lucie and Caloosahatchee — has been a perennial problem since the 1890s, when humans began tinkering with the lake’s plumbing. Among the hundreds of miles of canals dug throughout the region were two that connected the Caloosahatchee and St. Lucie to tide waters.
Those links enabled fresh water from the lake to flow into the rivers, which diluted the salinity levels of the brackish estuaries on the coasts. While most of the headlines and expense of “getting the water right” have focused on lowering levels of phosphorus and nitrogen levels caused by decades of farming and development, salinity levels and water depth play equally vital roles in the health of the system.
Isaac’s stormwater not only created lethal conditions for oysters by lowering salinity levels, but also brought other pollutants and toxins to the rivers. This week, the Martin County Health Department warned residents to avoid contact with water near the Roosevelt Bridge because of high fecal bacteria levels.
On the lake, though, more rain water means better fishing and bird watching. Lake Okeechobee has been ranked the second-best bass fishery in the U.S. and is a popular locale for national bass fishing tournaments. More water in the marshes and wetlands will improve wading bird habitat and attract more birds and bird watchers to the region, considered one of the top bird watching destinations in the world.
But when lake levels become too high and threaten the integrity of the dike around the lake, as they did after Isaac, the U.S. Army Corps of Engineers releases water from the lake into the Caloosahatchee and St. Lucie estuaries. Those releases began Sept. 19 and increased Oct. 3, as stormwater continued to flow into the lake twice as fast as it could be pumped out.
“When you deal with Mother Nature, we all have hardship,” said Martin, who has been in the fishing business for 30 years. “You just have to have faith.”