Scientists attack nitrogen plan

The province has ordered a massive upgrade of Winnipeg's waste water treatment system in order to limit the amount of nitrogen and phosphorus dumped into the lake.

The goal is to control the amount of harmful blue-green algae -- fed by the two nutrients -- which blooms across much of the lake during the summer.

But the city's waste water upgrade will cost about $1.8 billion and the province has also demanded Winnipeg spend up to $50 million on a treatment process meant to remove extra nitrogen from waste water.

But the scientists said in a letter this week that removing nitrogen from the sewage Winnipeg sends to the lake was misguided policy.

"Why waste all that money spending it on something that's not going to make a pittance of difference?" said Hedy Kling, a Winnipeg-based algae specialist, who signed the letter.

Studies have shown the bacteria that form the algae that has become Lake Winnipeg's scourge can draw as much nitrogen from the air in about three weeks as city waste water adds to Lake Winnipeg in an entire year.

Scientists from the United States and Israel, as well as Canada, said in the letter the province's response to the problem of blue-green algae in the lake has involved making only "minor reductions" in the nutrients responsible.

Their letter to the provincial Clean Environment Commission, the arm's-length agency that advises the government, underlined concerns that the province remained off the mark almost nine years after its Lake Winnipeg strategy was announced.

"We disagree with the government's plans to improve the health of Lake Winnipeg by making minor reductions in inputs of both phosphorus and nitrogen, rather than making much larger reductions in phosphorus alone," the scientists said.

By themselves, phosphorus reductions have restored the health of lakes worldwide, their letter went on to say.

Scientists who attached their names to the letter did so without identifying their places of work.

The letter originated at an October conference at the University of Winnipeg, organized by the Lake Winnipeg Foundation, a group working to maintain the health of the lake's watershed.

"It was raised at the time that somebody should write a letter," said Michael Stainton, a Winnipeg nutrient chemist who signed the letter.

The letter represents the latest salvo from the scientific community challenging the province's Lake Winnipeg strategy.

Almost since its inception, the strategy to lower levels of phosphorus and nitrogen in the lake has borne criticism from scientists who advocate controlling phosphorus alone would be effective in eliminating the algae blooms.

Phosphorus and nitrogen enter the lake through effluent from waste water treatment plants and fertilizer runoff.

The letter recommends the government focus not only on controlling phosphorus levels in sewage from Manitoba communities but from lands throughout the Red River basin.

The scientists even suggested the government's goal of returning Lake Winnipeg to a "pristine" state was folly.

"Lake Winnipeg is no longer a natural lake," the letter said. "Lake Winnipeg is now a hydroelectric reservoir with a commercial fishery surrounded by a large watershed that has been intensively developed for agriculture, livestock production, mining, forestry and urban centres... The notion of managing nutrients with the goal of restoring Lake Winnipeg to a 'natural' state is imprudent."

Such efforts by scientists to influence government might be succeeding.

Earlier this year, the province acknowledged it would take another look at its policy of removing nitrogen from Lake Winnipeg-bound waste water.

"We said we were open to further scientific debate on the removal of nitrogen and this remains true today," a government spokesman said Saturday.

The opposition Conservation critic joined the chorus of voices criticizing the government's Lake Winnipeg plan.

"We need a sign that the NDP government is taking the health and protecting of Lake Winnipeg seriously," said Tory MP Heather Stefanson. "It's time for the NDP to do what's right and listen to science."

joe.paraskevas@freepress.mb.ca

Republished from the Winnipeg Free Press print edition December 21, 2008 A3