What’s up with the thick, green water and dead fish in Matlacha Pass?

Right now the water in Matlacha Pass is green, thick and nasty with dead fish floating down canals, and neighbors are wondering what’s wrong.

“Yesterday we must have had 10 or 12 of them just stuck along my mangroves,” said Charlie Murgia, a Matlacha resident.

A typical Wednesday afternoon for Murgia involves sitting on his deck, sipping a cold drink, watching the water.

But lately, he can’t stand it.

“It looks like toilet water!” said Murgia. “It’s just brown, murky, with a real pungent smell.”

And that nasty water is bringing a horrific death to fish.

“We’d see them like porpoising, trying to gasp for air,” said Eric Bagranof, a Matlacha resident. “Then they would swim in a little circle, and they would just die. It was very sad.”

The Florida Fish and Wildlife is currently working to figure out what’s causing this.

So far, the Florida Department of Environmental Protection has noted low dissolved oxygen.

So WINK News Reporter Amy Galo asked FGCU water expert Serge Thomas for some insight.

Turns out, the heat doesn’t help.

“Fish have to work a little bit harder than us to get their oxygen,” said Thomas. “When it gets hot, you actually have less dissolved oxygen in the water, which is what the fish are breathing.”

Hurricane season exacerbates the issue.

“Tropical Storm Debby brought in a lot of water,” said Thomas. “That water also carries nutrients, carries eventually, bacteria, also what we call total suspended solid. So that means silt, sand, clay, etc, that makes the water more turbid.”

Turbid water lets in less light, leading to less oxygen.

“Especially at night, when there is no light, so (there’s) no photosynthesis, and you have all the respiration going on: the fish, the zooplankton, the algae, the plants.”

Everyone wants a piece of that oxygen, and some fish just can’t survive it.

WINK asked Thomas if there’s a quick fix, and the answer is no.

Thomas said these sorts of low oxygen events happen naturally, but they’re also happening more and even getting worse.

To fix it, we’d need to rethink how we build here in Florida, adding more natural buffers.

“There’s many things you can do, but there is no silver magic bullet, right?” said Thomas. “It’ll take a long time. We have to rethink the way we are building. We have to rethink the way we’re moving water across the landscape to avoid those spikes of water rushing to the estuaries. The best would be to move away from the edge of the water, whether it’s rivers or coastlines, and move more inland.”

It also doesn’t hurt to be cautious of your gardening and landscaping.

“Limit the amount of nutrient that we’re putting on on golf courses and lawns,” said Thomas.

The FWC is still investigating what led to the turbid water and fish deaths on Matlacha, and WINK will keep you up to date with the latest developments.