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Water-Related News

LIFTED: Lake Alert for Lake Emerald

Based on the latest results obtained by city staff from sampling Lake Emerald on September 15, 2021, the Lake Alert for Lake Emerald has been lifted.

At this time, there are no toxins present in Lake Emerald, but blooms may still occur.

There are always risks that could be associated with swimming, recreating, or irrigating in and from water with algal blooms, please use your own caution.

If you see a visible bloom present, please report it to the FDEP Algal Bloom Dashboard, which can be found here:

Original Lake Alert:

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.