Finding Solutions for Growth: Constructed Wetlands Part of a Healthy City

For the City of Edmonton wetlands are a critical component of both its support for biodiversity and water quality management.

Edmonton’s rapid growth over recent decades has lead to great transformation of the city’s human-dominated landscape. One of the City’s new challenges is the need to manage the additional storm water runoff from commercial and residential development with the City’s existing infrastructure.

“Water quality enhancement is something that we have to recognize and consider in the city, as the runoff from everyday activities – from roads, backyards, or wherever it may be – all eventually gets to the river,” said Grant Pearsell, Director of the City of Edmonton’s Biodiversity Office. “We do want to protect the ecosystem  and wetlands have a big part to play in that.”

Pearsell explained that wetlands provide such effective water management that the City has constructed wetlands  in order to mimic their natural ecosystem functions, such as flood control and water filtration.

The City has been building constructed wetlands since about 1995, originally as storm water ponds to mitigate floodwaters. Water quality became an issue due to the pressures of growth, so the City began designing storm water ponds that would provide water quality enhancements. That led to another redesign to mimic natural wetlands in terms of configuration and plants.

Over the past 10 to 15 years the City has undertaken projects that focused more on a commitment to biodiversity in some of the constructed wetlands. Pearsell noted that the city’s development industry is committed to improving methods of constructing wetlands, and that university research has also contributed to improvements in wetland design.

Although the City of Edmonton is not formally recognized as a Wetland Restoration Agency by the Government of Alberta, the preservation of natural areas, including wetlands, is part of its culture.

“This really about Edmonton’s long-term community values and the protection of the ecological network and natural areas system,” said Pearsell, noting citizens’ appreciation for wetlands for recreation, contemplative and spiritual values. “They provide a bit of a respite to get away from everyday city life.”