New Brunswick

Canoeing, kayaking barred in Moncton park after blue-green algae return

Moncton barred use of the Irishtown Nature Park reservoir for canoeing and kayaking Friday after blue-green algae were found along the waterway's banks.

Algae also found in drinking water supply, though city says it's safe to drink

Isabelle LeBlanc, Moncton's director of communications, says the city is working with two consultants and the provincial departments of health and environment on the blue-green algae in the city's water supply. (CBC News )

Moncton barred use of the Irishtown Nature Park reservoir for canoeing and kayaking Friday because of blue-green algae collecting along the banks of the waterway.

The algae were noticed when water samples were collected from the reservoir on Friday morning, said André Cormier, a city spokesman. The algae have been a problem in the reservoir in previous years. 

Blue-green algae are a bacteria that can produce toxins harmful to people and animals.

The bacteria are naturally occurring, and conditions like warm temperatures, high levels of nutrients and other factors can cause the algae to multiply quickly and create "blooms."

The city has warned pet owners to keep dogs out of the water and prevent them from drinking it.

Notices and signs will be posted along trails in the park, the city stated in an advisory issued Friday afternoon.

The reservoir north of the Trans-Canada Highway is not used for drinking water.

Jones Lake and Centennial Park remain open for recreational uses such as boating and kayaking.

The Irishtown advisory was issued two days after the city again detected blue-green algae in the Tower Road reservoir, part of the Turtle Creek watershed.

The watershed southwest of Riverview supplies Greater Moncton's drinking water.

Tower Road reservoir is Greater Moncton's secondary water source. Blue-green algae were detected there for the second year in a row. (Tori Weldon/CBC)

Isabelle LeBlanc, the city's director of communications, said in an interview Friday morning that the water supply is tested daily and remains safe to use.

It's the second year the city has dealt with the algae in its water supply. Once present, the bacteria often return.

The city has hired two consultants and is working with the provincial departments of health and environment, LeBlanc said.

"We're looking at different mitigation measures," she said.

The city is also examining changes to the water treatment plant, which was not built to deal with algae.

The watershed has two reservoirs along Turtle Creek. The lower reservoir has served as the main source of drinking water since 1962.

A single water sample from that reservoir in September last year showed low levels of blue-green algae. The algae were not detected in the raw water going to the water treatment plant, though.

The Tower Road dam, completed in 2014, holds back the upper reservoir. It was built to expand the region's drinking water capacity.

That's where most of the blue-green algae were found last year and again this year.

LeBlanc said the rotting stumps of trees left behind during construction of the reservoir are believed to be one of the contributing factors in the appearance of the algae. The stumps, she said, were left in place when the reservoir was flooded to help prevent erosion.

She said the consultants are working to determine what factors are behind the algae's presence in the watershed.