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The marshes on Île Bizard were among 11 local sites that received the second-worst pollution rating. (NATASHA FILLION)

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Algae alarm sounded for local water

Pollution levels in Île Bizard wetlands and St. Laurent reservoir have risen

CHRISTOPHER MAUGHAN
The Gazette
Tuesday, July 29, 2008

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The marshes on Île Bizard were among 11 local sites that received the second-worst pollution rating. (NATASHA FILLION)

Blue-green algae could infiltrate Montreal's streams and
lakes if the city doesn't do a better job of going after polluters
dumping phosphorus into waterways, environmental groups warn.

"We know the chemical that drives algae blooms is phosphorus," said
Daniel Green, a scientific adviser to the Sierra Club of Canada. "So
if there's a seagull or a loon or a goose that comes from Baie
Missisquoi with bacteria on its feet, then you have a recipe for an
algae bloom."

A report on the water quality of streams and ponds on the island of
Montreal made public this month found 14 of 20 small bodies of water
studied by the city are contaminated by phosphorus.

Water quality last year was about the same as in 2006, except for
two bodies of water where it deteriorated: Brunante Lake, a
rainwater reservoir in St. Laurent, and the wetlands on Île Bizard.
They were among 11 local sites that received a pollution rating of
IR4, the second-worst on a five-point scale.

"We're all aware that wetlands act as important natural filters,"
said Anne-Marie Saint-Cerny, director of the Fondation rivières, a
Montreal-based water conservation group.

"Losing one could destroy an entire ecosystem."

Blue-green algae is typically associated with restrictions on
swimming and closed beaches. Nobody swims in marshes or rainwater
reservoirs, but that's no reason to ignore potential algae
formations, Green said. Toxic strains of algae can cause
gastrointestinal and neurological problems in animals.

"If, God forbid, we got one of those strains in one of Montreal's
lakes, there would be animal die-off," he said.

The city has done well in identifying pollutants in the island's
waterways, Green and Saint-Cerny said. But they also agreed that
Montreal needs to do a better job of looking into who's doing the
polluting.

The sharp drop-off in the water quality of the Île Bizard wetlands
in 2007 suggests there are new polluters at work, Saint-Cerny said.
Most of Île Bizard's marshes were rated IR2 (the second-best
ranking) in 2006.

"There's a new source that we have to find and deal with," she
said.

Saint-Cerny was extremely critical of the city's record in
following up on cases of water pollution. For instance, she said, La
Ronde and Île Charron's Auberge des Gouverneurs were allowed to dump
sewage straight into the St. Lawrence River for years before the
city took action.

But Guy Deschamps, director of Montreal's water-monitoring unit,
said the city is tough on polluters, giving a recent case on Nuns'
Island as an example.

"When we found that people had connected their waste lines to the
storm sewers going to the river, we joined forces with the borough
to solve the problem. We just finished on July 6."

The decrease in water quality on Brunante Lake and the Île Bizard
marshes is the result of natural causes, Deschamps said.

"Two-thousand and seven was a really dry year," he said, noting
that a lack of rain can cause higher levels of contaminants to show
up in testing.

Asked if he's worried about a potential algae bloom, Deschamps
said: "Not really."

"It's improbable on Brunante Lake because that lake is often
replenished with underground water," he said.

As for the Île Bizard swamps, Deschamps said he said he is
confident a wetter 2008 will produce better results during the next
round of testing.