MARTIN COUNTY — If you live in Martin County, you may have received a notification from the local Department of Health warning about elevated levels of enterococcus bacteria in the water.
The Martin County Department of Health tests for the bacteria weekly at several beaches and locations along the river, including Charlie Leighton Park and the Roosevelt Bridge.
Nick Clifton, a health officer with the Martin County Department of Health, said enterococcus can serve as an indicator of water quality and potentially signal the presence of other contaminants.
"It's a good indicator bacteria. It comes from the intestinal tract of humans and animals, so it can be an indicator of other larger problems with the body of water," he said. "If you were to ingest it, it could cause an upset stomach, digestive tract issues, diarrhea, and then also if you have any kind of abrasions or cuts on the skin, it could lead to some irritation there and possibly some rashes."
Recent alerts may seem more frequent during the rainy season, and Clifton said rainfall can contribute to changes in bacteria levels.
"The main way that we would probably see it would be from runoff, like large rain events with more water ending up in the bodies of water," he said. "Typically, when you see it the most is after the rainy season starts or large rain events in general. Where we test, it's also tidally influenced."
Clifton said tides can also affect what is detected at individual testing locations.
"If we're getting an outgoing tide, that might be an indicator of stuff that's further inland, or if we're getting an incoming tide and we're sampling closer to the inlet, sometimes we'll see the rainfall is not having such an impact," he said. "So there's a lot of different factors that could come into play."
The health department categorizes readings based on colony forming units, or CFUs. Clifton said readings below 35 CFUs are considered good, readings from 36 to 70 CFUs are considered moderate and readings above 71 CFUs are considered poor.
When readings reach the poor category, the Department of Health issues an advisory. Clifton said people should use caution when an advisory is posted.
"We try to tell folks to avoid contact with the water and prolonged contact with the water," he said. "And if you have open lesions or sores or cuts, make sure you're flushing those out, washing cuts and scrapes. Use your best judgment."
Clifton also noted that testing represents conditions at a particular point in time, meaning bacteria levels can change from one day to the next.
"I know these are point in time samples. It could be elevated one day, but not the next," he said. "But if you have concerns or you're immunocompromised or have any kind of sores or lesions, then try to avoid the contact with the water if possible."
While water quality can remain elevated for periods during wetter parts of the year, Clifton said conditions generally become more stable during cooler and drier months.
"We see some of the sites will have like a few weeks of poor water quality. We mentioned in Charlie Leighton Park. We'll see that mostly with the higher levels during the rainier times of the year," he said. "And then when we get into the cooler months or less rainy, it seems to clear up and be a little bit more consistently good."
The Department of Health posts water quality alerts regularly on its website at martin.floridahealth.gov.