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Remediation & Regeneration

Wildlands Remediation

Since the oil refinery was dismantled in the 1980s, the Wildlands has been transformed through remediation that has involved the landowner, The City, numerous clubs and volunteers, university students, the Inglewood Community Association, and the dedicated Inglewood Wildlands Society. Remediation has involved pumping liquid petroleum out of the water table, skimming oil off the top of water-filled recovery trenches, and phytoremediation strategies through which grasses, shrubs and trees process and neutralize petrochemicals. The Wildlands includes a band of phytoremediation on its east edge, recently installed by Suncor and aimed at preventing contaminants from flowing toward the river.

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The Wildlands used to contain a small wetland pond built as part of environmental restoration efforts in the 1990s. It is dry due to past droughts and has been decommissioned. At the southern border of the Wildlands, a separator trench that recovered oil from groundwater has remained fenced off from public access for many years and now forms a wildlife refuge with dense vegetation that provides wildlife habitat.

Sanctuary Regeneration

Efforts to restore the grassland and riverine forest habitats are ongoing, with plantings and protections such as screens wrapped around larger tree trunks to prevent beaver harvesting.

In June 2013, heavy rainfall triggered catastrophic floods along the Bow, prompting states of emergency and evacuations. The Inglewood Bird Sanctuary, like many areas in the floodplain, was hard-hit. Large volumes of silt were deposited over habitats, infrastructure was washed out, and trees were uprooted. In addition, bridges and view platforms in the lagoon were severely broken. Some have been repaired but others have not. Replacement of damaged platforms is being considered carefully. Bend in the Bow is also considering using weirs at both ends of the lagoon to control normal water flows to support waterfowl habitat.

Corridor Regeneration

The 2013 flood also damaged banks of the Bow River in the Corridor between the Sanctuary and Pearce Estate Park. In some places entire banks were eroded and washed away. A damaged stretch of riverbank south of Blackfoot Trail is the site of a bioengineering demonstration project currently being led by the Province of Alberta, in coordination with The City of Calgary. Bioengineering is an approach incorporating living and nonliving plant material with natural and synthetic earthwork materials to stabilize slopes, control erosion, and establish vegetation. The project will include an education plan to demonstrate bioengineering techniques.

In the inland portion of the Corridor, along the historic railroad bed, extensive tree plantings to create an “urban arboretum” are included as part of Bend in the Bow. The tree species to be planted will be an extension of the tree tests conducted by William Pearce a century ago. Pearce procured, planted and observed a wide variety of species to determine what grew best in Calgary to address various applications such as windbreaks, hardiness, suitability for arid conditions, street tree use, and beautification. His experiments even included a bioengineering project to stabilize fragile riverbanks using cottonwood poles lying in trenches and green brush willow.

Pearce Estate Park Regeneration

Pearce Estate Park’s wetland, coldwater stream and floating fens were constructed through a collaborative effort between Ducks Unlimited and The City of Calgary partially in response to The City’s 2004 Wetland Conservation Plan. Berms around the floating fens were constructed from soil excavated to make the water bodies.

The 2013 flood brought damage to the riverine forest of Pearce Estate Park similar to what occurred at Inglewood Bird Sanctuary. Since then most has been cleaned up, though debris caught in trees and beaver screens near the river remains as a reminder.

The flood had a significant impact on the Bow Habitat Station’s Discovery Centre and Fish Hatchery. While the floodwater stopped just short of the buildings and the only physical damage was a few inches of flooding in the basement, a combination of loss of electricity and flooding of fresh water wells throughout the park that support the hatchery meant that fish in the aquariums and hatchery ponds had to be evacuated. The flood also destroyed Harvie Passage, the man-made high and low water channels built into the edge of the Bow River to safely convey non-motorized boats and fish past the large irrigation weir, and much of the adjacent riparian vegetation. To mitigate this damage, Harvie Passage is currently being rebuilt in a more protected side channel and a flood protection landform is planned for Pearce Estate Park.

Like at the Sanctuary, efforts to restore the riverine forest habitat are ongoing, with sapling plantings as well as beaver screens wrapping tree trunks.