Water quality declining in Matlacha Pass

Something rotten is filling the air from the green water near Matlacha Pass.

“We’ve seen quite a few dead, small fish, mainly, but like six, eight, 10 fish I’ve seen floating in the mess, and it comes at night,” said Matlacha resident Richard Salkeld.

“It’s just yucky looking,” said resident Joanne Smith.

Add to it the terrible smell.

“It’s almost nauseating. You breathe in and you don’t want to breathe in again. You hold your breath if you can,” said Salkeld.

The Florida Department of Environmental Protection said the water around Matlacha is low on dissolved oxygen.

“When it gets hot, you actually have less dissolved oxygen in the water, which is what the fish are breathing,” said Serge Thomas with the Florida Gulf Coast University Water School.

That, mixed in with pollutants and recent Tropical Storm Debby, is a recipe for disaster.

“Tropical Storm Debby, you know, brought a lot of water. That water also carries nutrients, carries eventually, bacteria,” said Thomas.

Which leads to turbid water.

“The water gets less light, so you have less oxygen through the process of photosynthesis,” said Thomas.

A problem that gets even worse at night.

“Seagrasses, algae, bacteria, fish, all of them. At night, they all respire, and they take any bit of oxygen that you might have,” said Thomas.

And some fish just can’t survive it.

Thomas said while these low oxygen events can happen naturally, he thinks what’s happening on Matlacha is likely a human-driven problem.