Cyanobacteria keeps 2 Moncton lakes closed

With water levels still low during a warm summer, people in Moncton are being warned not to let their dogs swim or drink the water at Jones Lake or Irishtown Nature Park.

Heather Fraser, the city's natural resource program co-ordinator, said officials have been monitoring cyanobacteria in the water weekly since early July when water temperatures rose.

"Algae is starting to form in the water column, and we're starting to see counts a little higher than what we'd like to see," Fraser said.

Irishtown Nature Park was closed in late July and Jones Lake was closed two weeks ago. Centennial Park is not affected because it's already closed for maintenance.

The closures at Irishtown Nature Park and Jones Lake came after cyanobacteria, also known as blue-green algae, were found in the water and testing showed they were toxic. 

"Once that happens, we close the water to recreation for kayaks and canoes and also for people who let their dogs swim and drink the water," Fraser said. "So we just do that definitely as a precaution." 

She said Jones Lake didn't have cyanobacteria but did have high E. coli counts.

"We closed that to recreation to stabilize, hopefully, through some rain or wind action." 

Because Jones Lake is so shallow, Fraser said, the city will have to keep a close watch on what is happening. 

Over the previous few summers, the city has seen the green colour of algae before seeing a high bacteria count in tests, but this summer the opposite happened.

"That's why it was more important to close it because people don't see the green, and they think it's still OK to let the their dogs in [the water]."

Fraser said she'll get the results of the latest weekly tests Friday and decide whether Irishtown Nature Park and Jones Lake can reopen. 

If the count is low for cyanobacteria but high for E. coli, Jones Lake will remain closed. 

"That will be a weekly monitoring program until the waters start to cool," Fraser said.

As for the Turtle Creek and Tower Road reservoirs, the source of drinking water, there have been no issues this summer, she said.