An influx of saltwater could spell doom for the blue-green algae that has closed Mississippi Coast beaches from state line to state line during the height of tourist season, said Phil Bucolo, a visiting assistant professor at Loyola University in New Orleans who has studied alga for 18 years.
The algae growing in the Bay of St. Louis and Mississippi Sound, which is potentially toxic, is a freshwater species. It grew and thrived with the influx of Mississippi River water from the Bonnet Carré Spillway, opened this year for an unprecedented duration to prevent river flooding in New Orleans and surrounding communities.
The algae needs water to survive, Bucolo said. If it did wash ashore in a storm surge, the algae would dehydrate and die.
The path is uncertain for a potential tropical storm currently churning in the Gulf of Mexico, but the National Weather Service is forecasting the highest storm surge in extreme southeastern Louisiana. South Mississippi is more likely to see heavy rainfall and flash flooding.
But Harrison County could get 1 to 3 feet of storm surge on top of a high tide, emergency manager Rupert Lacy said. Whether it will kill the algae is another question.
“It depends on how it churns in the washing machine,” Lacy said.
The bad news is that all the rain expected with the tropical system will mean more fresh water entering the Mississippi Sound from the Jordan, Tchoutacabouffa and Pascagoula rivers, and from the Bonnet Carré.
And more fresh water could mean another blue-green algae bloom.