Blue-green algae could be responsible for contamination in Halifax-area lake

Nova Scotia's Department of Environment is investigating a suspected blue-green algae bloom in Grand Lake, north of Fall River, after two dogs died and one person was sent to hospital Wednesday.

The province issued an emergency alert early Thursday morning, warning all residents who take water directly from Grand Lake to stop using the water immediately.

"What we do know is there's obviously a toxin," Julie Towers, the department's deputy minister, said Thursday afternoon. "Whether it's human-caused or a natural source is to be determined."

Residents near Grand Lake, who don't receive water from a municipal utility, are advised not to consume their water, or use it for cooking, bathing, swimming or boating, until told otherwise.

"No matter what the cause is, right now we want people to be careful and avoid contact with the water until we can find out exactly what's going on," Towers said.

The department said it's testing water samples taken from Grand Lake and Fish Lake for two types of toxins produced by blue-green algae, which can be harmful to humans and animals.

Rapid tests were completed to determine the presence of toxins, before the samples were sent to a lab to test for pesticides, organic and inorganic materials, and petroleum hydrocarbons.

A sample of sludge is also being sent to a specialist for identification.

The department said the advisory includes anyone who has a shallow drilled or dug well that is less than 30 metres deep and is within 60 metres of the lake.

All fishing on the Grand Lake watershed, including the full length of the Shubenacadie River, is also suspended until further notice, according to the Department of Fisheries and Oceans.

Halifax Fire said a hazmat team was sent to Oakfield Park Road near Grand Lake around 8:30 p.m. Wednesday, after receiving a report from a resident that the water could be contaminated.

The team secured the area but was unable to find the cause of the contamination.

"We can test for chemicals if we find a residue or container that's leaking but there was none of that to check," said acting district chief Pat Kline.

The investigation was then handed over to the Department of Environment, which was on site Thursday.

Towers said the investigation could take a few days as samples are being collected and sent to provincial labs for testing.

She said a helicopter will also be used in the area to help determine where samples should be collected.

A resident in the area told CBC News on Thursday that a woman was taken to hospital in Lower Sackville but is now recovering at home.

They also confirmed two dogs had been in the lake on Wednesday and later died at the Elmsdale Veterinary Hospital.

Dr. Amanda Stephenson, a veterinarian at the clinic, said there won't be a conclusive cause of death until testing on the lake is completed, but the dogs were showing signs of blue-green algae poisoning, including excessive drooling, lethargy, vomiting and diarrhea.

"Blue-green algae has that particular set of symptoms and it's fast-acting," Stephenson said.

"So you kind of wonder, with the warm weather we've had lately, it's possible. Of course there's other plant toxins out there, that's another possibility, and chemicals that somebody could have put out there."

Tap water is safe in Halifax, East Hants

Halifax Water and the East Hants Regional Municipality both confirmed Thursday morning that their water systems are not affected by this advisory after the emergency alert caused some confusion for customers.

In a statement, Halifax Water clarified that its tap water remains safe as it doesn't draw from Grand Lake.

"There's no effect on Halifax Water customers at all ... their tap water is perfectly safe to drink," said James Campbell, the spokesperson for Halifax Water.

The utility does operate three water systems within the same watershed as Grand Lake, including Bomont, Collins Park and Bennery Lake, but none of those systems draw water from Grand Lake.

The East Hants Regional Municipality also released a statement saying there is no known risk to its utility customers, although it does rely on the Grand Lake watershed.

"We know it's just generalized in Grand Lake right now so it's immediate users of the lake itself that need to be following extra due diligence right now," Jesse Hulsman, with the East Hants municipality, told CBC's Information Morning Halifax Thursday.

On Thursday evening, the municipality announced it would provide free drinking water to residents who can't use their water because of the advisory. Residents must bring their own containers and follow public health protocols, including wearing a mask and practising physical distancing. The water is being distributed at the East Hants Aquatic Centre between 6 p.m. and 8 p.m. AT.