By Allanah WillsSeptember 25, 2019 5:48pm@willsallanah

Your eyes aren’t playing tricks on you, some waterways in Chatham are appearing green because of an algae bloom.

On Monday, a “significant” bright green algae boom appeared on the Thames River. Jason Wintermute, manager of watershed and information services with the Lower Thames Valley Conservation Authority, explained that algae blooms are composed of microscopic organisms such as plants and bacteria.

“Under the right weather conditions and nutrient conditions, they basically over proliferate,” he said. “You’ll get a giant mass of these things and they’ll colour the river or other water bodies.”
Wintermute said the last time a similar algae bloom of this size was seen in Chatham was around the same time in the year of 2017.
“There was a series of them or perhaps it was just one that kind of peered out into the middle,” said Wintermute. “It lasted the end of September and into early October. It was kind of the same thing, the river turned this distinct green colour.”
According to Wintermute, it’s hard to say how long the current bloom will last. He said the length of algae blooms depends on the weather factors and how mother nature plays out.

“The bloom will grow when it got the right conditions,” he explained. “So if it has lots of warmth. In order for it to grow it needs food [and nutrients.] We’re in a river here so if we get any kind of weather that drops a bunch of rain and the river starts flowing faster than usual, then it could potentially get flushed out of the river… so its really just the climate, the weather conditions.”

The conservation team first noticed the algae bloom on Monday morning when it was limited to the community of Chatham and seemed to be the worse around Highway 40 to the Fifth Street Bridge.

“[Wednesday] when we drove in, the river was noticeably green around Dillion Road so the river is slowly flowing it down to Lake St. Clair,” said Wintermute.

Because Chatham residents don’t get their drinking water from the river, Wintermute said the algae poses no threat in that sense. Samples are however being tested by The Ministry of the Environment, Conservation and Parks to see if the bloom has the potential to be toxic.

“Certain blooms will produce a toxin that can have an impact on people. People will get rashes from it, in extreme cases if the dose is relatively high, its been known to kill pets and things like that that have been playing in the water,” said Wintermute. “So the samples have been sent away for those toxin tests by the ministry.”

Wintermute said the results are pending. Whether or not a bloom will have toxins depends on a variety of factors including environmental conditions.

“We can say in 2017 they did analyze for toxins as well and there was very little of the toxin found in that bloom in that time,” he explained. “This one’s shaping up to be a little different in terms of how it looks but the tests aren’t back yet to confirm.”