Officials are warning pet owners about toxic algae in lake and ocean water.

No waterways in western Connecticut have tested positive for the toxins that the blue-green algae can release, but it's the time of year when it can grow.  DEEP and town officials test waters like Lake Mohegan in Fairfield for the toxins weekly.

If a dog drinks water or licks its coat after being in water with this type of algae, they could become critically ill within an hour.

Dr. Erin Fleming, of Highway Veterinary Hospital, says a dog with symptoms that include vomiting, diarrhea, lethargy, tremors or a seizure should be checked out immediately by a vet, especially if the dog had exposure to water sources.

Fairfield Public Health Director Sands Cleary says anyone who sees the algae in the water should report it to officials.

Officials say it’s important to avoid swimming in water that is a bright green color and has a pea soup-like appearance.

Four dogs in Texas and North Carolina have died in recent days after exposure to blue-green algae.