The blob in the Don Valley
May 1, 02:04 AM
If you drive along the Bayview Extension near the Don Valley Parkway onramp this spring you can’t miss it. Rising out of the valley is an ominous brown-gray mound of mud and ice, oozing water full of road salt, motor oil and other pollutants unfiltered into the Don River.
It’s snow removed from Toronto’s city’s streets, and it’s causing serious and unprevented environmental damage to Canada’s most urban river. A 2005 environmental assessment conducted by the city concluded that continued use of the site without taking environmental protective measures would have ‘a major effect on the terrestrial’ and ‘aquatic systems’ in the area.
The environmental impact of the snow removal sites on the Don Valley was serious enough that the Task Force to Bring back the Don successfully lobbied the city to close the Pottery Road snow removal site further north along the river.
The Bayview/Bloor snow removal site is one of 15 destinations for the snow removed from Toronto’s streets. Snow removed from city streets this winter once again found its way onto the riverbank of the Don River. The site was last used in 2004 and before that in 1999.
The record snowfall this winter, over 200 cm, meant Toronto had to declare emergency snow removal measures. Over a three-week period in February and March, 500 privately contracted dump trucks hauled snow from our streets to the disposal sites.
At the Bayview/Bloor site, the impact is unmistakable. Newspapers, snow-shovels, bicycles; anything unfortunate enough to be caught in the path of the city’s snow removal trucks is littered around the site. Trees caught in the snow pile are dead; broken, twisted and caked in mud. A swamp of meltwater has formed around the site – the only life undeterred by its oily surface are snails – so abundant they’re impossible to avoid. The pebbles and rocks in the river below are stained red as the water flows downstream, under the Bloor Viaduct and off to Lake Ontario.
Road salt adversely affects sensitive species when it exceeds 200 milligrams per litre of water. Almost half of the test results taken between 2002 and 2005 in the river exceeded that, and the highest concentration recorded was almost 4,000 milligrams per litre. The result is a river that can barely support life. Only six pollution resistant fish species, such as Suckers and Chub, can be found in the river. In the west end of the city, the Humber River supports up to 30 natives species of fish.
In 2001, the city contracted a consulting firm to identify an environmentally sound strategy for dealing with the city’s snow removal. Soil analysis conducted found elevated levels of copper, iron, lead and zinc, in addition to sodium chloride (road salt). The final report issued in 2002 listed the direct discharge from the site into the Don River as an environmental issue. The report recommended constructing a water drainage and collection system to trap sediments and metals, as well as a litter fence to prevent garbage collected in the snow removal process from reaching the river. The 2005 environmental assessment concluded these measures would reduce the impact of the site on the river.
In October 2004, the Task Force to Bring Back the Don sent a communication to the Toronto Works Committee requesting a phase-out plan for the disposal site.
“It was a fairly long process,” says John Routh. He’s been a member of the Task Force to Bring back the Don for 10 years.
“We basically told the city that we’re opposed to having snow dumps in the valley period. But realized that options for relocating them we’re limited. So we proposed that we wanted to get one of them closed down. So we asked to have the Pottery Road site closed because it was further upriver and leave the Bayview one open because the polluted water would flow into the river.”
Following an October 2005 report from the general manager of transportation for the city, Gary Welsh, the Works Committee agreed to stop operations at the Pottery Road site, and also place a moratorium on development of mitigation measures at any valley site. While the short-term impact on the river may be more serious, the Task Forces hopes leaving the valley sites undeveloped will lead to their closure.
“We’re of two minds about that,” says Routh. “If advocate for onsite mitigation, like a meltwater pond to settle out the suspended particulates, then we’d be saying that we want to keep the snow removal site here permanently. Whereas our longterm goal is to remove that site completely.”
Until the site closes, however, there’s nothing stopping the meltwater from running directly into the river.
Nineteen years after the city formed a task force to address its dire state, the 38 km river still struggles with pollution caused by the city. The Task Force to Bring Back the Don was founded in April 1989, with a goal “That the Don River and its related recreation and wildlife areas be made fully useable, accessible and safe for the people of Toronto no later than the year 2001.”
Despite the formation of the task force, last December, Environment Canada rated the Don the most polluted river in Ontario and one of Canada’s top five worst polluted rivers. The 2007 Canadian Environmental Sustainability Indicators gave the river a 34.8 out of 100. The main problem is a glut of phosphorous, chlorine and ammonia, mainly from human and animal sewage, fertilizer and road salt.
“It’s a slow process,” says Routh. “The issues for the Don Valley are complex.
The main problem with the river is storm runoff. In a natural watershed, rainwater would be absorbed into the ground, and slowly seep into the river.
However 800,000 people live in the Don’s natural watershed, meaning much of the of the drainage basin for the Don River is paved over. with roads, parking lots and buildings. Whenever it rains, the runoff directly into the river, and along with it all the pollutants gathered from the urban environment.
The plan to divert the direct flow of water from Toronto’s streets to the Don was started in 2003. The 25-year plan will cost an estimated $1 billion to implement.
“These are long-term plans. We’re not going to solve them overnight.”
One of the big problems in downtown toronto is the sewer systems that manage storm water and sewage water are combined. The rainwater and sewage flows directly into the river. There are about 200 sites where Toronto’s sewers flow directly into the lower Don. The city must either replace the entire downtown sewer system or divert the flow to a containment system, where the water can be pumped out and sent to a treatment facility.
The Task Force sees modest success for the river in 2028 when the project is finished. While its impossible to eliminate all the contaminants in an urban environment
The flow of the river will be a lot smaller. There’ll be less contaminants, but it’s very difficult to clean it up 100 per cent. The water will be able to sustain more life. Right now there’s about 6 or 7 species of fish, but only pollution resistant ones like Suckers and Chub. Compared to the Humber river, where there’s 20 to 30 fish species there, it’s not as impacted.
posted by: Michael Lehan
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Michael Lehan is a media journalist based in Toronto, Canada