Levels of fecal bacteria have risen 150 times higher than safe levels in some Florida canals after record flooding last week.
Fort Lauderdale, just north of Miami, experienced massive flooding after 20 inches of rain left 20,000 people without power and closed the city’s airport.
Miami Waterkeeper, a non-profit organization, discovered a day after the historic rainfall that the water collected from the city’s canals contained an excess of enterococcal bacteria. In some cases, up to 144 times the healthy limit.
Enterococcal infections can cause vomiting, diarrhea and infections such as urinary tract infections, meningitis and wound infections. They live in a person’s intestines and appear in the stool. Their detection in water is a sign of contamination.
Local officials are warning residents to stay out of the water and not to swim or trudge through for fear of getting sick.
People try to save valuables as they wade through floodwaters in the Edgewood neighborhood of Fort Lauderdale, Florida April 13, 2023
More than 10 inches of rain has fallen in South Florida since Monday, causing widespread flooding
Enterococci are generally not harmful to humans in low concentrations. However, it can cause harm if it goes beyond a person’s digestive system in high levels.
It causes a disease called E. faecalis, which then causes problems with the urinary tract, stomach problems leading to vomiting, diarrhea and infection of the heart.
If there are more than 70 colony-forming units of enterococci — meaning they have the ability to replicate and grow — per 100 milliliters (ml) of water, the Environmental Protection Agency (EPA) deems water unsafe for swimming.
Miami Waterkeeper collected 10 samples from around the city on April 13, which has been compared to Venice, Italy, for its sprawling network of canals.
Himmarshee Canal, just north of the city’s Riverwalk, was found to contain a whopping 10,112 units of the bacteria per 100 ml — nearly 150 times higher than safe limits.
This is also 37 times higher than what would be expected in a used toilet, according to previous research.
On a normal day, the level of enterococci in the water will be between 40 and 300 per 100 ml of water.
Chris Caywood and Heather Caywood walk to their home that was inundated with floodwaters in Fort Lauderdale, Florida on April 14, 2023
Record levels of rainfall are leading to record levels of bacteria.
Aliza Karim, a water quality specialist at the nonprofit, told the South Florida Sun-Sentinel: ‘The results on the 13th on some sites are the highest detected in the last two years. We have never seen so many sites fail above 1,000.”
She added, “I wouldn’t recommend contact with the water. Fern should be fine, but fishing, or any kind of interaction with the water, I wouldn’t recommend until the blooms die down.’
Natalia Soares Quinete, a chemist at Florida International University who studies water pollution, told the local paper, “Even without flooding, the canals can already have high levels of coliform (bacteria).”
She said: “Those levels are a good indication of likely septic tank overflow. You have a lot of septic tanks in South Florida, and some of them fail, but even the good ones can overflow with this water.”
Ms Quinete said flood water in parks, where there is dog and human excrement, also flows into rivers.
She added: ‘The problem is these levels of coliforms [such as enterococci] are associated with other types of chemicals… that are toxic, such as pharmaceuticals and PFAS [per- and polyfluoroalkyl substances]. We don’t measure them, but they’re in it.’