What are they?
A wetland is a type of ecosystem that has both aquatic and terrestrial properties. There are many different types of wetlands. Some wetlands are covered by water for all or part of the year, while others do not appear wet but are sporadically or seasonally saturated and have a water table close to the soil surface.
The characteristics of a wetland are determined by soil type, topography, climate, available nutrients, the types of plants and animals present, and water chemistry. The plants and animals that live in wetlands are adapted to their unique conditions, forming biological communities that are different from the surrounding area.
Wetlands are among the most productive, complex and diverse habitats on Earth. They provide valuable ecosystem services, including recharging groundwater, sequestering carbon from the atmosphere, providing nursery areas for many species, and reducing the effects of drought.
How do wetlands influence water quality in the Bow River Basin?
Wetlands have positive effects on water quality. They can:
- retain and remove nitrogen and phosphorus,
- absorb contaminants, and
- trap sediment from water and slow down flow rates to allow settling and reduce erosion.
Because of these positive effects, constructed wetlands (wetlands built to mimic natural wetland processes) are often used for stormwater or other types of wastewater treatment. The type of treatment required will influence the type of wetland that is constructed. See our fact page on Stormwater for more information.
What can we do?
Wetlands improve water quality and provide valuable ecosystem services. We must therefore protect and improve the function of existing wetlands in Alberta. We must also construct additional wetlands for stormwater and other wastewater treatment.
Where can I find more information?
Alberta Wetland Policy
Facts About Water in Alberta – Benefits of Wetlands (pg. 19)
The role of wetlands in reducing flood damage
Ducks Unlimited Canada
Treatment Wetlands Second Edition
U.S. Environmental Protection Agency. (2015). Connectivity of streams and wetlands to downstream waters: A review and synthesis of the scientific evidence. EPA/600/R-14/475F, United States Environmental Protection Agency, Washington, DC. 388 p.