ANNE ARUNDEL COUNTY, Md. (WJZ) — As the official start to summer nears, Anne Arundel County health leaders are telling swimmers to stay away from three popular beaches.

Monique Griego has more on why the water is deemed too dangerous.

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County leaders say the beaches all had high levels of bacteria reading for three straight weeks.

Beachgoers in Anne Arundel County are being warned to stay away from certain waters due to high levels of bacteria.

“Once the weather gets warm, people are swimming and I think today, because of that sign, that’s the only reason people aren’t swimming,” said beachgoer Colette Preis.

Preis stayed on the sand after seeing a sign alerting people to the dangers at Londontown’s Arundel Road beach. County health leaders say its waters had 10 times the amount of bacteria deemed safe.

“I don’t think we’re going to swim there for a while,” said beachgoer Nina Brackman.

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While Londontown had the highest counts, Beverly Beach and Upper Magothy Beach also had elevated levels. Health leaders say several factors—including waterfowl and the recent heavy rain we’ve seen—can cause increased bacteria.

“It’s an indicator organism; it indicates that other harmful bacteria could be present that could make someone ill,” said Gerard Zitnik, Anne Arundel County Health Department.

County health leaders say high bacteria levels can lead to a list of health problems.

“If you accidentally drink some of the water, there could be gastrointestinal-type things,” Zitnik said.

Bacteria can also get into open wounds and sores and cause an infection.

Despite the danger, swimmers at Magothy Beach tested the waters out anyway.

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Health leaders plan to retest the water later this week and will then decide whether to lift the warning.