Lake Winnipeg has earned a disturbing new title from the Global Nature Fund (GNF), as the Threatened Lake of 2013.

"That this huge Canadian lake is faced with problems similar to those of lakes in more densely populated countries is hard to believe," stated the organization, which is based in Berlin, Germany.

GNF, the organization that created the International Living Lakes network, chooses the most-threatened lake in the world every year. Lake Winnipeg was nominated by Living Lakes Canada.

"This is the red flag," said Vicki Burns, outreach coordinator at the Lake Winnipeg Foundation.

'[The blue-green algae is] getting so big you can see it from...outer space.'—Vicki Burns, Lake Winnipeg Foundation

Burns, along with other experts, say blue-green algae is poisoning the lake.

"They're getting so big you can see it from a satellite from outer space," Burns said.

According to the GNF, nutrients and pesticides found in agricultural run-off and sewage discharge are partly responsible for causing the toxic algae.

"It's a consequence of our lack of responsibility to take care of the environment …and the only thing I can say is — it can only get worse," said John Werring, senior science and policy advisor at the David Suzuki Foundation.

To restore the lake the pollutants will have to be removed from the water, which Burns said could take decades and could cost millions of dollars.

But the cost of not doing anything could be more devastating — a dead lake.

"I don't want people to think there's no hope for Lake Winnipeg," Burns said. "There's lots of hope and we know quite a few things we can do to turn this around. We've just got to get going and start doing them."

Past Threatened Lakes of the Year:

2012: Lake Titicaca, Bolivia and Peru

2011: Laguna de Fúquene, Colombia

2010: Pulicat Lake, India

2009: Lake Atitlan, Guatemala

2008: Mahakam Wetlands, Indonesia

2007: Pantanal, Brazil, Paraguay and Bolivia

2006: Dead Sea, Israel, Jordan and Palestine

2005: Lake Victoria, Kenya, Tanzania and Uganda

2004: Lake Chapala, Mexico