Is the lake safe?

Orange County, Florida

Lake Olivia algae bloom status

Bloom seen

Latest state sample, 28 July 2025

Is Lake Olivia safe to swim in?

Florida's most recent sample from Lake Olivia, on 28 July 2025 at Lake Olivia - SW Shore, found a bloom and no microcystin toxin was detected. Blooms have been reported here in two separate years since 2019.

Avoid contact with green, scummy or discoloured water and keep dogs out of it.

Check today on the DEP Algal Bloom Dashboard
Years with blooms
2 of 7
Usual months
Jul and Oct
Highest toxin level
0µg/L
Data checked
24 October 2026
See it on the Florida map

Lake Olivia algae bloom history

Florida's Department of Environmental Protection sampled Lake Olivia 13 times between 2019 and 2025. Staff saw a bloom on 5 visits (38%).

Microcystin, the most common algal toxin, was not detected in any sample tested here.

Reports have risen in the last three years compared with the three before.

  1. 2019 2 of 10 visits
  2. 2020 No visits
  3. 2021 No visits
  4. 2022 No visits
  5. 2023 No visits
  6. 2024 No visits
  7. 2025 3 of 3 visits
Bloom seen, no toxin foundNo visits Visits with no bloom seen

When do algae blooms happen at Lake Olivia?

At Lake Olivia, reports are most often logged in July and October.

Reports are spread across the year, with 60% between May and September.

Blooms can appear, move with the wind and fade within hours or days, so the time of year is only a guide.

January: 0% of reports
February: 0% of reports
March: 0% of reports
April: 0% of reports
May: 0% of reports
June: 0% of reports
July: 60% of reports
August: 0% of reports
September: 0% of reports
October: 40% of reports
November: 0% of reports
December: 0% of reports
Share of reports by month. Darker bars are the peak months.

Recent Lake Olivia algae reports

Recent reports came from 8 different locations around Lake Olivia, including Lake Olivia - SW Shore, Lake Olivia at Boat Ramp and Lake Olivia at Center. A bloom in one cove or beach doesn't mean the whole lake is affected, and conditions can differ a short distance away.

DateLocationResult
28 July 2025 Lake Olivia - SW Shore Bloom seen · microcystin not detected
14 July 2025 Lake Olivia - SW Shore Bloom seen · microcystin not detected
1 July 2025 Lake Olivia - SW Shore Bloom seen · microcystin not detected
20 November 2019 Lake Olivia at Boat Ramp No bloom seen · microcystin not detected
20 November 2019 Lake Olivia at Center No bloom seen · microcystin not detected
30 October 2019 Lake Olivia at Boat Ramp No bloom seen · microcystin not detected
30 October 2019 Lake Olivia at Center No bloom seen · microcystin not detected
17 October 2019 Lake Olivia @ N Boat Ramp - HAB No bloom seen · microcystin not detected
17 October 2019 Lake Olivia @ Center - HAB No bloom seen · microcystin not detected
2 October 2019 Lake Olivia @ Center Bloom seen · microcystin not detected
2 October 2019 Lake Olivia @ Northern Ramp Bloom seen · microcystin not detected
24 September 2019 Lake Olivia No bloom seen · microcystin not detected

What the Florida results mean

Florida records whether staff saw a bloom at each visit and, when a sample is tested, how much microcystin it contained.

Bloom seen
Staff saw a bloom at the sampling site, and no toxin was found or tested.
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.

Is Lake Olivia safe for dogs?

Dogs are at the greatest risk from toxic algae. They swallow water while swimming, eat scum on the shore and lick algae off their fur afterwards, and a small amount can kill a dog within hours.

  • Keep your dog on a lead near water that looks green, scummy, foamy or discoloured, and away from algae washed up on the shore.
  • If your dog gets in, rinse it straight away with clean water and don't let it lick its coat.
  • Call a vet immediately if your dog vomits, drools, has diarrhoea, staggers, shakes or seems weak after being near the water.

Read the full guide to toxic algae and dogs: symptoms, what to do in the first minutes and how vets treat it.

Health effects of toxic algae

Blue-green algae (cyanobacteria) can produce toxins that affect the liver, nervous system and skin. Swallowing water during a bloom can cause stomach pain, vomiting and diarrhoea. Skin contact can cause rashes, and breathing spray from the water can irritate the eyes, nose and throat. Children are at higher risk because they are smaller and more likely to swallow water.

How to spot a bloom

Toxic blooms can look like pea soup, spilled paint or green streaks on the surface, and they can also be blue, brown, white or red. Scum often collects along the shore downwind. If you can't see your feet in knee-deep water, or you aren't sure, stay out.

Don't drink untreated lake water, and don't boil it to make it safe: boiling doesn't destroy algal toxins. If you feel unwell after contact with the water, contact a doctor or Poison Control on 1-800-222-1222.

Nearby lakes with algae reports

All Orange County lakes with algae reports

Questions about Lake Olivia

Is there algae in Lake Olivia right now?

Florida's most recent sample from Lake Olivia, on 28 July 2025 at Lake Olivia - SW Shore, found a bloom and no microcystin toxin was detected. Florida publishes its data in yearly batches, so for today's conditions check the DEP Algal Bloom Dashboard and the signs at the shore.

When was the last algae bloom at Lake Olivia?

The most recent entry in Florida's data is from 28 July 2025 at Lake Olivia - SW Shore: a bloom seen during sampling.

Has Lake Olivia had toxic algae before?

Yes. Blooms are recorded in 2 of the 7 years from 2019 to 2025, most often in July and October.

Can dogs swim in Lake Olivia?

Keep dogs out of the water whenever a bloom is reported or the water looks green, scummy or discoloured. Dogs are the animals most often killed by algal toxins because they swallow water and lick their fur. If your dog swims in water that might have algae, rinse it with clean water and call a vet if it vomits, drools, staggers or seems weak.

Can you eat fish caught in Lake Olivia during a bloom?

If you keep fish caught during a bloom, health agencies advise removing the guts and liver and rinsing the fillets in clean water before cooking, because toxins collect most in the organs. Some agencies advise not eating fish from an active bloom at all, so follow local guidance.

About this data

This page uses official records from the Florida Department of Environmental Protection (DEP), which published as a yearly file; current sampling is shown on the DEP dashboard. Reports are grouped by waterbody. The site was last rebuilt on 24 October 2026.

States only test some lakes, some of the time, so a lake without a recent report hasn't necessarily been checked. This page is independent, isn't affiliated with the State of Florida, and isn't health advice. View the source data.