HEAVY RAINS HELP REDUCE TOXIC SCUM ON AREA LAKES
BY: CHRIS MORRIS - LEGISLATURE BUREAU
20 AUG 2013 07:29AM
Heavy rains this summer have helped prevent the formation of poisonous blue-green algae in New Brunswick lakes but researchers warn that, thanks to climate change, it’s a problem that’s here to stay.
Donald Killorn, executive director of the not-for-profit environmental research group, Eastern Charlotte Waterways, said Monday the toxic scum is posing a growing threat to the province’s lakes and people are starting to fight back.
“It is posing more of a threat to our lakes, but it is not confined to just New Brunswick,” said Killorn, who is based in Black’s Harbour.
“We don’t have the science yet to really point a finger and say, ‘This is why this is happening.’ But some of the likely causes are a changing climate, which is disrupting the ecology, and also direct inputs of nutrients and disruption of natural habitats.”
Fertilizer run-off, loss of protective buffers around shorelines and sewage discharge are some of the nutrient feeders that scientists believe are contributing to the blooms of cyanobacterial organisms.
Killorn said low water levels appear to be a factor in the formation of blooms, which is why the abundance of rain this year has helped prevent uncontrolled growth of the organisms.
With the right conditions, the bacteria can grow in large quantities. The blooms range in colour from dark green to yellowish brown and they can produce toxins that may adversely affect people and animals that come in contact with the contaminated water.
There have been several reports in recent years of dogs dying after they played in or drank algae-infected water.
Last summer, the most dramatic bloom was in Lac Unique, near Edmundston, where Killorn said the water became so contaminated with algae “it looked like pea soup.”
Pierre Moreau, president of the cottage owners association on the lake, said area residents now are working together to try to prevent the cynobacteria blooms.
Moreau said the conditions have been excellent this year to head off a bloom, especially the heavy rains, but he said people are remaining vigilant.
He said the group has given residents trees and shrubs to plant along the shoreline and help address erosion. The shrubs will absorb phosphates, he said.
As well, the association is collecting data on water temperatures.
Moreau said people who want to live near a lake have to be active participants in ensuring its survival.
“We have to continue with our efforts to educate residents and sensitize them to the importance of not spreading chemical fertilizers on their lawns, of not using products with phosphates,” he said.
“We hope people won’t forget what happened in 2012 and will continue to make an effort.”
The New Brunswick Health Department has issued blue-green algae advisories for five lakes this summer: Lac Unique, Lake Utopia, Chamcook Lake, Lac Baker and the Irishtown reservoir.
“The Department of Health encourages the public to enjoy the outdoors but be aware that blue-green algal blooms can be unpredictable,” the department states on its website.
“Advisories are issued to inform local recreational water users to help make informed decisions on water use in the affected area and to be more aware to look for the formation of highly visible blooms and scum, which pose the most risk.”
So far this summer, there has not been a large bloom in New Brunswick.
Killorn said that his group also is collecting data on water temperatures and other indicators, primarily in Chamcook Lake and Lake Utopia.
The organization has received a grant from the New Brunswick Environmental Trust Fund to study blue-green algae and other elements of lake ecology.
“For all intents and purposes we are very much at the mercy of Mother Nature,” Killorn said.
“Of course, that is becoming more true in all aspects of our lives.”