- April 27, 2022
Maintaining a healthy Sarasota Bay is vital for the area’s quality of life and local economy.
Longboat Key’s proximity to the bay connects the water’s health to many facets of island life and business.
The Observer caught up with Sarasota Bay Estuary Program Executive Director David Tomasko to discuss the environmental health of Sarasota Bay, the effects of losing about 2,000 acres of seagrass and what people can do to help the water quality.
We really have to be kind of like specific to different regions.
We have three systems south of Siesta Key Drive, and we’ve got continuing concerns in that part of the bay. There’s some evidence of maybe getting a little bit better, but we have continued problematic conditions in the lower two-thirds of the bay, and that’s kind of unfortunate. So we need to find out what we need to act upon.
Then we have Roberts Bay. In that region, we’re actually seeing signs of improvement that seems to be associated with recent things that have been done in Sarasota County to act upon what have been problems for the last couple of years. And that is, for about five years, we had overflows of wastewater that were miles away from the bay, but nonetheless looked like they brought about an adverse impact to the bay. And those overflows of wastewater — and it wasn’t raw wastewater, it was treated wastewater — but it had a lot of nitrogen in it. Those overflows aren’t really occurring anymore.
Because they’ve acted upon it and because they’re planning on upgrading that wastewater treatment plant to nutrient removal technology, we think that the problem has been solved. And if they actually move forward as quickly as they’re planning on upgrading the wastewater, we don’t think we’re going to have that problem again.
(In the upper bay from Siesta Key Drive to Manatee Avenue), we think that the biggest problem there was really two red tides in 2016 and 2018. And then, in between the two, we had Hurricane Irma. And Irma didn’t cause a lot of flooding, but it made the bay very turbid.
We had red tide, hurricane-induced muddy water and then we had another red tide. (It) set us back a lot in terms of it caused, we believe, about 2,000 acres of seagrass to die because (it was) just too dark for too long. But the water quality has already responded positively, so we’re already seeing visibility up in that part of the bay is beautiful again.
I would say the upper part of the bay. The water quality is back, but we lost 2,000 acres of seagrass, and we want to get it back, and we don’t want it to take too long. … We need to start figuring out whether or not we need to do something other than what we’ve done in the past.
And what I mean is, a lot of people think: "Oh, the Indian River Lagoon and all those manatees starved to death. Well, let’s plant seagrass." Well, they’re starving to death because the seagrass has died because the water quality sucks. If you plant seagrass, it’ll just die again. That’s not the case in the upper part of Sarasota Bay, but we’ve never had to plant seagrass to gain seagrass. We’ve just acted on our water quality, so if we went long enough and the water quality stays good, it might come back by itself, but we may want to jumpstart it with doing some transplanting in that area.
Roughly that lost 2,000 acres of seagrass probably means there’s something like 30 million fewer fish in the bay, and that’s not all giant keeper snook, it’s little fish, … but there’s more fish per square meter in a part of the bay with seagrass than right next to it in an area with no seagrass at all. … It’s also a big drop in the food supply for manatees.
There (were) a couple steps, and we’ve done some of them already. … When we talk acres of seagrass, it’s from mapping efforts done by the Southwest Florida Water Management every two years from a plane that’s flying at like 9,000 feet. ...
(The 2,000 acres of lost sea grass) is not completely gone, but it’s gone or it’s very, very thin. So that’s the first thing. It is a real loss.
The second thing that we've done is we've actually worked with some of the state agencies to go out and look for a seed bank. In other words, if we get the water quality right, will they come back on their own? And, we only found a viable seed bank at about 15% of the sites, so the vast majority of the areas where we lost seagrass, it’s still not there and (there are) no seeds for it to come from.
So the next thing that we need to do is, if we take the seagrass and put it down in like eight feet of water where we have this loss, is it going to grow? And if it doesn’t, then you just stop. Then, apparently, it’s not good enough water quality. But if it does grow, then we have to come back and say, "Alright, what are we going to do about this?" We can’t dig up 2,000 acres and put it somewhere else, but is there something we could do to kind of jumpstart restoration?
Longboat Key has a pipeline underneath Sarasota Bay that goes from Longboat Key towards Manatee County Southwest Regional Treatment Plant. The pipeline is … (nearly) 50 years old. … And if you go out and swim across the bay where that pipeline is, the bottom above the pipeline has sunk down roughly about 2 feet deeper than the surrounding areas…
One of the things that we think can help is as Longboat Key moves forward with replacing that sewer line. … We hope that (there are) opportunities to raise the bottom of the bay in the area where it’s kind of … down 2 feet or so. ...
Sarasota County is going to be spending a massive amount of money on wastewater treatment plant upgrades. And when they do that, and some of the wastewater treatment plans will happen very quickly, like within the next three years it looks like, as that happens, we should dramatically reduce the possibility of having wastewater issues in the bay.
Pick up after your pets, watch that you don’t over-fertilize, don’t blow your grass clippings out into the water or don’t blow them into a storm drain. Those are things can absolutely do to help improve the water quality of the bay.