The dirty Don

Encased in concrete walls for much of its length, poisoned by runoff from sewers and streets, the turbid Don is Ontario's dirtiest river, and one of the worst in Canada.

The river, which flows a mere 38 kilometres from its nearly pristine source on the Oak Ridges Moraine to its garbage-choked, oil-slicked mouth on Lake Ontario, scored a lowly 34.8, on a scale of zero to 100, in an Environment Canada calculation of water quality, released yesterday.

The main problem is a glut of phosphorous, chlorine and ammonia, mainly from human and animal sewage, fertilizer and road salt.

The Humber, Credit, and others in the region fared better in the ranking of 395 rivers across the country, based on averages of seven contaminants from 2003 to 2005.

The absolute worst, anywhere, are Quebec's Yamaska and Bayonne rivers, despoiled by pollution from pulp mills and languishing at around 27 points.

The figures are contained in the third annual Canadian Environmental Sustainability Index, which also shows southern Ontario has some of Canada's worst air quality. Environment Canada compiles the index from water sampling done by other government agencies.

The main question is whether the Don is improving.

"The Don is symbolic of a lot of the problems with environmental policy in Ontario," said Mark Mattsen, president of Lake Ontario Waterkeepers. "The river is hardly a river at all. It's an embarrassment."

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