The North Saskatchewan River winds through the center of Edmonton, its waters and the surrounding landscape forming a green spine that spreads a network of ravines out into nearby neighborhoods. Since 1904, when the Canadian city was incorporated, it has prioritized this river ecosystem. But the city is growing — from 600,000 people in 1990 to nearly 900,000 today — and that’s pushing development and transportation infrastructure up against this riverine system. Habitats are being reduced in size and fragmented by roads, creating many risks for the river valley’s wildlife.
Recognizing the threat urban development posed for the river ecosystem, Edmonton embarked on an ambitious effort to accommodate growth while at the same time protecting wildlife and habitat. In 2007, the city built its first wildlife passage — a culvert that allows small mammals to pass between two sections of ravine that had been cut up by a road. More were soon planned. Led by the city’s planning department, the city has now built 27 wildlife passages, reconnecting habitat and enabling the safe movement of animals of all sizes — everything from birds to amphibians to mammals such as weasels, porcupines and moose.
But Grant Pearsell, director of Parks and Biodiversity for the Department of City Planning, says the city isn’t simply designing wildlife passages. “It’s more that we’re accommodating wildlife in the design of our infrastructure,” he says. “There’s a difference.”
Bringing nature back into cities — or preventing it from being destroyed — is a growing imperative in cities across the world. Taking lessons from conservation biology and applying them to the built environment, cities are proactively creating habitat for certain animals, increasing urban tree canopies and even reintroducing species that have long been displaced by roads and buildings. ...