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Water-Related News

City of Orlando issues LAKE ALERT for Lake Emerald

On July 21, 2021 the Florida Department of Environmental Protection (FDEP) tested water samples from Lake Emerald and determined that potentially unsafe concentrations of microcystin (toxins) are present in the lake. As a precaution, we are advising everyone to refrain from swimming, recreating and irrigating in/from Lake Emerald until further notice.

For reference, cyanobacteria/blue-green algae are always present in the water, however, not all bacteria have the ability to produce toxins. Toxicity is hard to predict because a single species of algae can have toxic and non-toxic strains. Nothing can be done to treat algae blooms without causing massive fish kills. In the coming weeks, the city will work closely with Florida Department of Environmental Protection (FDEP) to monitor Lake Emerald. Once we obtain more information on the status of the lake, we will continue to update this Lake Alert.

Please encourage your neighbors to register for the Lake Alert at so they too will get important information about Lake Emerald directly.

In the meantime, as we stated above, the city would advise refraining from swimming, recreating and irrigating in/from the lake until further notice.

More information about harmful algae blooms from the Florida Department of Health: