Is Lake Mann safe? Toxic algae status

Orange County, Florida. Harmful algal bloom (blue-green algae) reports from the Florida Department of Environmental Protection (DEP).

Data checked 24 October 2026. Florida data is published as a yearly file; current sampling is shown on the DEP dashboard.

20

sampling visits since 2020

17

visits where a bloom was seen

3.7 µg/L

highest microcystin result

Year by year

Each box shows visits where a bloom was seen, out of all sampling visits that year.

2020 1 of 1
2021 None
2022 12 of 14
2023 3 of 4
2024 None
2025 1 of 1
Toxin detectedBloom seen, no toxin foundNo visits

Reports at Lake Mann are most often logged in January, March and April.

Recent reports

DateLocationResult
29 January 2025 Lake Mann - McQueen Park Bloom seen · microcystin not detected
16 March 2023 Lake Mann - McQueen Park Bloom seen · microcystin not detected
23 February 2023 Lake Mann - McQueen Park Bloom seen · microcystin not detected
31 January 2023 Lake Mann - McQueen Park No bloom seen · microcystin not detected
11 January 2023 Lake Mann - McQueen Park Bloom seen · microcystin not detected
19 December 2022 Lake Mann - McQueen Park No bloom seen · microcystin not detected
1 December 2022 Lake Mann - McQueen Park Bloom seen · microcystin not detected
6 September 2022 Lake Mann - McQueen Park Bloom seen · microcystin not detected
16 August 2022 Lake Mann - McQueen Park Bloom seen · microcystin not detected
28 July 2022 Lake Mann - McQueen Park Bloom seen · microcystin not detected
14 July 2022 Lake Mann - McQueen Park No bloom seen · microcystin not detected
27 June 2022 Lake Mann - McQueen Park Bloom seen · microcystin not detected

What the results mean

Bloom seen

Staff saw a bloom at the sampling site. A sample may then be tested for toxins.

Toxin detected

Microcystin, a liver toxin made by blue-green algae, was found in the sample.

8 µg/L or more

At or above the level where the US EPA recommends swimming advisories for microcystins.

Dogs and toxic algae

Dogs face the greatest risk because they swallow water and lick algae off their fur. If a bloom has been reported, keep dogs out of the water and away from scum on the shore. If your dog swims in water that might have algae, rinse it with clean water straight away and call a vet if it seems unwell.

Common questions

Is Lake Mann safe to swim in?

The most recent entry in Florida's published data is from 29 January 2025: bloom seen · microcystin not detected (Lake Mann - McQueen Park). Blooms have been recorded at Lake Mann in 4 different years, so treat green, scummy or discoloured water with caution. For current conditions, check the DEP Algal Bloom Dashboard and posted signs.

When does Lake Mann get algae blooms?

In the state's records, reports are most often logged in January, March and April. Blooms are most likely in warm, calm weather, but they can appear at other times of year.

Source: Florida Department of Environmental Protection (DEP), official data. This page is independent and not affiliated with the State of Florida.