Many readers have called the Tampa Bay Times wondering about the impact of the recent massive sewage discharges into Tampa Bay and other nearby waters. We reached out to scientists and government agencies to explore short-term risks for swimming and fishing. This is a working list. We will try to answer questions as they come in. If you have one, leave a comment.
First thing's first: Can you swim?
In general, yes. If you want to be extra careful, make sure the beach you are going to is monitored by some kind of agency, be it your local city or through the state Healthy Beaches program. None of the nine monitoring points in Pinellas County were under any advisory as of Wednesday, but those spots are all on the Gulf of Mexico side. In Hillsborough County, one beach — Simmons Park Beach — was under an advisory Wednesday. Just because there is an advisory doesn't mean the beach is closed. Swim at your own risk. All six Hillsborough County spots monitored by the Healthy Beaches program are along Tampa Bay.
If you're going to a beach not monitored under the Healthy Beaches program, check with the city where it is located. St. Petersburg reopened its three beaches — North Shore, Spa and Lassing — Tuesday after two days of favorable testing.
Robert Ulrich, a marine microbiologist at local company PureMolecular and associate researcher at the University of South Florida, said there shouldn't be a problem going to a monitored beach that gets a thumbs up from regulators.
"I would definitely trust the scientists involved in monitoring," he said. But if you are elderly, have a compromised immune system or are bringing small children, "I would definitely be more cautious. If my toddler or infant were swimming at the beach, I might wait a few more days regardless of the monitoring, just to make sure."
What if you're going to an unmonitored area?
Because there is no data on some areas, it's unclear how clean the water is, said Holly Greening, director of the Tampa Bay Estuary Program.
"One of the questions citizens have is, 'What about areas that aren't established swimming beaches?'" she said. "I think that's a good discussion to have at the regional level — how sure are we that the monitoring at the beach regions is adequate for other parts of the Bay also?"
Tampa Bay is big. Some areas circulate better than others. It takes longer for water to flush out of Old Tampa Bay near Oldsmar than in other areas, for example, Ulrich said.
"It doesn't flush very well," he said. "How this thing cures itself is through dilution. … If you have a closed system way back in the bay, or poor water circulation, those are your biggest problems, because it just doesn't flush the impacted sewage water out very well."
That said, at this point, most of the sewage pumped into Tampa Bay after Hurricane Hermine should be broken down by now, said Valerie Harwood, chair of the Department of Integrative Biology at USF.
"There should be little to no residual leftover from that contamination," she said. "There may be special circumstances so I'll qualify that: If there was very little circulation — you may have some effect."
What precautions can you take?
The U.S. Environmental Protection Agency backs up the assertion by Ulrich and Harwood about poorly circulated areas.
"In areas that are not monitored regularly, choose swimming sites in less developed areas with good water circulation, such as beaches at the ocean," the agency says on its website. "Avoid swimming at beaches where you can see discharge pipes or at urban beaches after a heavy rainfall."
How do you get sick if exposed to sewage?
The EPA says swallowing water is the easiest way to be exposed to water-borne pathogens. It's also possible to be exposed by touching polluted water or by getting it in your eyes. The EPA says in rare cases open wounds can expose people to infection or illness.
Keeping your head above water and not digging in the sand can reduce the chance of exposure.
Gastroenteritis is the most common illness associated with sewage spills, according to the EPA, with symptoms including nausea, vomiting, stomachache, diarrhea, headache or fever. More serious diseases are possible in "highly polluted water," the agency says.
"Fortunately, while swimming-related illnesses are unpleasant, they are usually not very serious — they require little or no treatment or get better quickly upon treatment, and they have no long-term health effects," according to the EPA.
Is it safe to eat the fish you catch?
Scientists we talked to broke it down this way: fin fish — redfish, seatrout and snook, for example — are safe to eat. Exercise caution with shellfish, however.
"These human pathogens in the sewage impacted waters typically don't make their way into the muscle tissue of fin fish," Ulrich said. Wash you hands, wash filets with clean water and cook the fish all the way through, though, he said.
"Most importantly, proper cooking," Ulrich said. "If there are any viable organisms that did make their way through the cleaning process in fin fish muscle tissue, it usually is taken care of by proper cooking and proper temperatures. Don't eat your fin fish medium rare."
As far as filter feeders (think clams, oysters, mussels), be careful, Ulrich says. "They're very good at concentrating pathogens that are in the water columns," he said. Any bacteria or viruses filtering through a filter feeder "gets concentrated in the muscle tissue. They're not really good at expelling it. If you were in the practice of eating or undercooked oysters or clams from the greater Tampa Bay area, I would definitely advise against that."
The state Department of Agriculture monitors shellfish conditions. As of Wednesday, the Boca Ciega Bay area was closed off due to "excessive rainfall."