My naturalist friend told me that the chinook salmon were running up the East Don River to spawn. I was surprised and delighted to hear this—mainly because of what I’d already heard about the Don River. And what I had already seen and smelled during my walks along the East Don River. There were times in spring when the river appeared milky grey and totally lifeless. And in several places along the river, the smell of sewage was overwhelming.
The most common fish in the Don are minnow-sized species of creek chub, blackness dace and long nose dace, white suckers, and carp–all pollution-tolerant and high-temperature tolerant fish.
In her 2014 book, Reclaiming the Don, Prof. Bonnell discussed the history of the Don as a story of neglect and abuse. This once beautiful river, spilling into one of the largest marshlands in Lake Ontario, has been recast with concrete; Its natural meander constricted and straightened, tributaries piped and paved over and its waters contaminated to the point where the river caught on fire—twice.
“Over the past 200 years,” writes Bonnell, “almost all of the significant wetlands within the watershed have been drained or filled to support urban development [one of the main reasons for its unruly floods, by the way—wetlands act as sponges to balance water fall, retention and flow]. The six tributaries of the lower river have mostly disappeared, buried by fill or encased within sewage infrastructure.”
In the 1960s, the river’s course was further altered to accommodate the construction of the Don Valley Parkway, the city’s main commuter route. The Don started to resemble a straight ditch.
Between 2003 and 2005, Environment Canada surveyed water quality at 10 Canadian lakes and 349 rivers. The Don placed in the bottom five percent, among only 16 sites to earn a “poor” rating. Key problems included nutrient enrichment through phosphorus, found in fertilizers and human and animal waste. Phosphorus levels in the Don have fallen by 66 percent over the past 30 years, but they’re still five times higher than Ontario’s target of 0.03 milligrams per litre.
The same is true of bacteria from pet waste, leaky sewers and sewage overflows. Levels vary with weather and location (as the water flows south through the watershed, it gathers more pollutants), but measurements on the lower Don are typically 30 times greater than the 100 E. coli per 100 millilitres that Ontario deems safe for swimming. Another indicator of urban growth around the Don is chloride, mostly from road salt, which is up 68 percent over the past 20 years.
In 2007 the Don scored a rating of “poor,” 34.8 out of 100 on the federal Canadian Environmental Sustainability Index. The Humber, by contrast, got a “marginal” 60.2 and the Credit River a “good” 90.5. One Environment Canada official this week said the study, based on data contributed by the province, shows the Don’s outstanding pollutants are phosphorus, nitrates and chloride. The first two are found in fertilizer and wastewater and natural material such as leaves in a stream; the third is road salt, said Jean-Francois Bibeault, a manager of water quality indicators and development.
The Toronto and Region Conservation Authority’s own report card most recently listed the water quality throughout the watershed as “very poor,” awarding it an “F” grade. The remaining forests in this once tree-rich valley were also deemed “poor” and given a “D” grade. Groundwater quality in the watershed, however, was said to be “good,” with the best water found, not surprisingly, in the Oak Ridges Moraine, the source of the Don. If the river can be cleaned up as it flows south, good water will follow.
In 2007, on the heels of the reports of the Don River’s failing health, Waterfront Toronto announced that an international competition would be held to come up with a “world-class” plan for the river: a plan to transform 125 hectares around the mouth and Keating Channel into parklands and mixed-use residential neighbourhoods. The object was to create “an iconic identity for the Don River”
The winning proposal, by Michael Van Valkenburgh and Associates of New York, Behnisch Architekten of Los Angeles and Toronto urban designer Ken Greenberg will create, “a spectacular and compelling vision for the area … balancing and integrating urban and natural environments.” The landscape designers described it as “a new type of territory where city, lake and river interact in a dynamic and balanced relationship.”
While the massive plan to restore the Don’s habitat at its mouth to Lake Ontario is commendable, this is only one part of a larger need to restore its entire watershed. Ironically, the large development and wetland park construction is greatly motivated by the need to address flooding concerns on the Lower Don.
The irony of this Lower Don naturalization is that if similar efforts were done to naturalize the Upper Don watershed (e.g. remove impermeable surfaces too close to ravine slopes, aggressive replanting of native trees and shrubs, removal of channelized sections of the river, re-establishing wetlands), flooding would be greatly reduced.
Things the city must do: remove concrete channelization to main river and daylight tributaries; restore function and integrity to floodplain natural vegetation; restore functional wetlands; address and repair old and failing storm and sewer infrastructure associated with the Don; identify and reduce or remove contaminant sources to the Don mainstem and tributaries; educate the public—particularly those living in the Don watershed—on stream stewardship and the importance of cleanup.
Things we can do: Though “the task is an enormous one,” James McArthur, executive director of Friends of the Don East said [we] can bring back the Don by shading the river and taking it out of concrete channels. Residents can help by disconnecting downspouts, using less salt and replacing asphalt driveways with permeable surfaces. “We [as individuals] can make a big difference in the right direction,” he said.
Nina Munteanu is a Canadian ecologist / limnologist and novelist. She is co-editor of Europa SF and currently teaches writing courses at George Brown College and the University of Toronto. Visit www.ninamunteanu.ca for the latest on her books. Nina’s bilingual “La natura dell’acqua / The Way of Water” was published by Mincione Edizioni in Rome. Her non-fiction book “Water Is…” by Pixl Press (Vancouver) was selected by Margaret Atwood in the New York Times ‘Year in Reading’ and was chosen as the 2017 Summer Read by Water Canada. Her novel “A Diary in the Age of Water” will be released by Inanna Publications (Toronto) in 2020.