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Water-Related News

Orlando issues Alert for Lake Formosa

UPDATED Information

Lake Formosa is being closely monitored for presence of microcystins (toxins) by City of Orlando and Florida Department of Environmental Protection (FDEP) staff. On Thursday, January 21, 2021, the City of Orlando staff will be sampling Lake Formosa again for algal toxins. The city's tests will provide an update on the presence of microcystins, but the official toxin determination is obtained from FDEP’s laboratory data. We will not know results from FDEP for another 2-3 weeks. At this time, the Lake Alert remains in effect until FDEP’s results indicate that Lake Formosa is deemed safe by current state standards.

Please continue to call the Lake Alert number, 407.246.2220, for the most up-to-date information regarding your lake. During weekdays, the City's Lake Alert website, will also have the latest information.

On December 29, 2020, the City of Orlando was notified that the Department of Environmental Protection (DEP) had collected samples at Lake Formosa that tested positive for microcystins (toxins). Upon this information, City of Orlando staff also sampled Lake Formosa, confirming the positive results for the microcystins, resulting from an algal bloom in the lake at levels deemed unsafe by state standards. Due to these conditions, we advise all activities involving swimming, recreating, and irrigating in/from Lake Formosa suspend until further notice

These conditions are caused by algae blooms that could be a result of several factors, including warmer water and excessive nutrients that can come from a combination of fertilizers, septic tanks, yard waste and pet waste.

Because of the potential for harm to humans and pets, the City staff is working closely with the DEP to continue routine testing until the algae bloom declines and toxin levels are reduced to acceptable state standards. The city will keep the Lake Alert in place until conditions are deemed to be safe. Please encourage your neighbors to register for the Lake Alert at so they too will get important information about Lake Formosa directly.

For more information about Harmful Algal Blooms, please visit this page on the Florida Department of Health website.

If you should have additional questions, please contact Kari Lara-Murabito at