Heavy rain and thunderstorms continue across southeastern Minnesota Thursday evening.

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Summer calls for flip flops, towels and cooling off at the lake. But as Minneapolis begins its brief imitation of a tropical paradise, what some beachgoers see through their sunglasses is enough to keep them out of the glistening water.

“We saw algae bloom all along the shoreline and know that it can result in illness, so we had to come up with a different option,” said Erica Mellum after she and her children scouted out one of their favorite beaches at Lake Nokomis. They chose to splash around in Lake Hiawatha’s playground wading pool instead of swimming in lake water that looked like pea green soup.

High levels of E. coli and blue-green algae blooms like the one Mellum and her family saw can lead officials to temporarily close beaches and post advisories warning people to avoid the water if there is an increased risk of getting sick from swimming.

Rachael Crabb, water resources supervisor for the Minneapolis Park and Recreation Board tells people to scan the water before they swim and to be aware of the weather. If environmental conditions align, blue-green algae can form blooms that produce toxins.

“If it’s the middle of summer or if it’s been really wet or hot blue-green algae will be growing too,” Crabb said.

Blue-green algae, technically known as cyanobacteria, are tiny organisms that naturally occur in lakes, rivers, ponds and other surface water. When they grow quickly and form blooms, they can cause illness in people and animals that swallow, inhale or come into contact with affected water.

Another risk to swimmers is exposure to E. coli bacteria, which has led to the temporary closure of Lake Harriet Southeast Beach, Bde Maka Ska North Beach and Lake Hiawatha Beach. 

Recent weather has contributed to high E. coli levels, Crabb said: “We’ve had so much rain and so much high water and we’ve got storm water coming into the beaches, which carries bacteria with it.”

E. coli lives in human and animal digestive systems. Dr. Anupama Kalaskar, the medical director for the Infectious Disease Department at Children’s Minnesota says everybody has it in their GI tract.

“Often it won’t necessarily do anything, but it can cause illness when people ingest feces-contaminated food or water,” Kalaskar said. This makes swimming when there are high E. coli levels a risk.

Severe cases of E. coli can involve fever and vomiting, but “the main symptom is diarrhea,” Kalaskar said. “Things to really look out for are persistent diarrhea, like having multiple episodes, because that can lead to dehydration.”

Poor water quality kept Erica Mellum and her children out of Lake Nokomis, but they still look forward to swimming there on a different day this summer. “We had many options of where to go today, but we chose the pool closest to home and we’re here, having a good time.” 

Tips to stay cool and safe during extreme heat

Minneapolis Parks officials recommend that people follow these health guidelines when swimming: 

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Erica Zurek

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High levels of E. coli and blue-green algae blooms can lead officials to temporarily close beaches and post advisories warning people to avoid the water if there is an increased risk of getting sick from swimming.

Stay out of the yuck: What to know about E. coli and other water hazards

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