People in the Moncton area are being asked to stay away from the reservoir at Irishtown Park because of a potential health hazard from algae growing there.

Algae had not been a problem at the reservoir in July, but blooms appeared during the weekend's hot, dry weather.

"We do test it right directly at the University of Moncton," said Heather Hawker, natural resource program co-ordinator for the City of Moncton.

"We do have some biologists that test the species of algae there, but we send it to Montreal for confirmation of species before we open the reservoir again to recreation."

The blue-green algae, or cyanobacteria, forms in shallow, warm, slow-moving or still water. The city has had trouble with the algae in previous years.

Hawker said there was enough rain in July to keep the problem at bay, but the dry heat over the weekend created perfect growing conditions.

Can be toxic

The algae can be toxic. Some are known to attack the liver, the nervous system or simply cause skin irritation.

"Our first alert is no dogs swimming and so on in the water," said Hawker.

"When it starts to bloom we do close it to recreation for boating and kayaking and so on. It's more just a pro-active measure."

It is likely the bloom is relatively harmless, she said, but it could be a week or more before the algae is positively identified. Until then, people and their pets should stay away from the water.

Even algae considered non-toxic can cause stomach upset for people and their pets if consumed in large quantities. An update on the algae will be posted on the park's billboards and website.