Moncton's water supply has cyanobacteria. Here's what the city is doing about it

Loon calls echoed across the Turtle Creek watershed on a recent overcast July morning as two people in a small boat collectedwater samples from the Tower Road reservoir, near Moncton.

The boat was laden with coolers packed with small bottles that, within hours, would be sent off to labs for testing.

It's part of the city's monitoring for cyanobacteria, or blue-green algae, in the water supply for the province's largest metro area.

The photosynthetic bacteria can be found in many waterways and isn'tnecessarily harmful, but some types can produce toxins harmful to humans and animals.

The discovery of cyanobacteria in the reservoir six years ago triggered a multimillion-dollar research and upgrade effort that's ongoing.

Soon, the city will decide how to spend millions more at its water treatment plant to address the risk of toxins.

The city says water flowing through taps across Moncton, Dieppe and Riverview remains safe. The sampling is to know whether that could change.

"We want to make sure we're monitoring so that we know what's coming into the water treatment plant all the time," Nicole Taylor, the city's director of water and wastewater, said in an interview.

"And it also gives us time to prepare."

WATCH | How Moncton is addressing cyanobacteria in its water supply:

A look at how Moncton is dealing with cyanobacteria in its water supply

1 year ago

Duration 3:15

Moncton's water supply has cyanobacteria. Here's what's being done to deal with it.

Some of the samples collected that humid morning are trucked to Dalhousie University in Halifax where researchers working with the city look for changes in both chemical and microbiological quality and consider ways to treat the water.

"Our lab has tested for the algal species, but also for the ways, in this case for the City of Moncton, the ways that we can safely remove and treat them," Graham Gagnon, a Dalhousie professor and director of the Centre for Water Resource Studies, said in an interview.

Gagnon said cyanobacteria in a water supply isn't unique to Moncton.

"It's certainly something that has occurred across the Maritimes. We have worked with a number of water utilities," Gagnon said.

A 2016 Health Canada publication sayscyanobacteria blooms have been observed in drinking water sources in almost every province and territory.

With the right conditions, such as warm temperatures and a high nutrient load, cyanobacteria can multiply quickly and create blooms. The blooms can sometimes produce cyanotoxins.

Research cited in the Health Canada publication has indicated temperature increases and changes in climate variability can have a strong effect on cyanobacterial growth rates and bloom formation.

The World Health Organization says exposure to those toxins can cause a range of health effects, including nausea, vomiting and diarrhea. More serious effects include liver damage and neurotoxicity, which is damage to the brain or nervous system.

A cyanobacteria bloom was found in the Tower Road reservoir in September 2017.

That reservoir was completed in 2014 to increase the region's raw water supply. It flows into the lower Turtle Creek reservoir and onto the treatment plant.

Cyanobacteria was also found in the Turtle Creek reservoir in 2018. But, Taylor said it wasn't detected in water entering the water treatment plant.

"We need to be sure that the water is potable all the time. So if our treatment plant might not be able to handle cyanobacteria and their toxins in the future, we need to be sure that we invest and ensure that the water is always potable."

During the pandemic, the city spent $6 million to reduce the risk of a bloom clogging the water treatment plant southwest of Riverview.

The second phase, which is ongoing, involvesresearch and testing how to deal with potential toxins.

The research portion is expected to be complete by either the end of thisyear or early 2024.

"It's almost done," Taylor said. "That will determine what type of treatment technology we might need to address cyanotoxins."

That's part of where Gagnon's research comes into play.Gagnon and Taylor saidwhat works in one watershed or treatment plant may not in Moncton, so various options are being tested.

The city already has $22 million in funding, some provincial and some federal, to pay for the research and any further upgrades to the plant once there's a decision on the next step.

Taylor said construction should be complete by 2026.

If a bloom results in toxins in the water, the city would order people not to consume it. Boiling would not remove the toxins.

"Obviously we don't want to be in that situation," Taylor said.

"We want to make sure that upstream we do what we can to prevent it from happening if we can, and that if it does happen, then we can treat it at the treatment plant."