Florida Bay Waters Suffering From Salinity & Lack Of Freshwater

MIAMI (CBSMiami) - Florida Bay is one of our most treasured waterways. It's known worldwide for incredible fishing and for its natural beauty, but there's potential trouble lurking under the water.

When Hurricane Irma blew through, it hit Florida Bay hard. It was already recovering from a seagrass die-off in 2015 caused by hypersalinity in the water, killing off seagrass in a large area of the bay.

"Like our heart, we can't take in too much salt because your blood pressure goes up and you just keep consuming salt, you get to a point and you'll have a heart attack," explains Dr. Steve Davis, Senior Ecologist from the Everglades Foundation.

"The same thing happens out here, too much salt and they just can't perform at a level they need to and they die," he said.

Dr. Davis also shared that parts of Florida Bay have more salinity than the ocean. The cause is a lack of fresh water that should keep the bay brackish.

"When it's not getting enough freshwater and it's not getting flushed well by the tides," he explained, "then it just evaporates water and when water evaporates off the bay the salt stays behind and the salt can  increase pretty dramatically where it's up to two times the salinity in the ocean off the Florida keys."

That hypersalinity can cause seagrasses to die, so it'll take away habitat that's needed for vibrant marine life.

Capt. Brett Greco leads fishing charters. He tells us healthy seagrass is critical.

"The seagrass is important for fish," Capt. Greco explains.

"It's where they find their forage, their feed.  They need that grass to have a healthy population of bay shrimp, crabs, baitfish.  It's where they find all their forage."

The solution is to get more freshwater into Florida Bay.  That happens naturally with rain and it should come naturally from the Everglades, but years of man-made obstacles have cut off much of that supply.

"We've got to turn on that spigot that gets more freshwater coming in so we can help to flush out some of the salinity in these basins," Dr. Davis said.

Dr. Davis is thrilled with Everglades restoration projects, like elevating Tamiami Trail, allowing water to flow more freely. And there are ongoing projects supported by Governor Ron DeSantis, like a reservoir south of Lake Okeechobee.  That would allow lake water to be filtered naturally — and sent south to the Everglades and Florida Bay.

"It's getting fresh was from Lake Okeechobee, sending that water south and that's what Everglades restoration projects like the reservoir will do and at the same time those projects sending water south are cutting discharges that are unwanted to the Caloosahatchee and the St. Lucie Rivers,"  Dr. Davis said.

For now, Florida Bay is in a good recovery.  "What we're seeing is an intact healthy seagrass community right here," Dr. Davis points out during a Florida Bay tour.

He says now it's just a matter of doing what we can to keep that recovery going and the key, he says, is Everglades restoration.