Constructed Wetlands?
A relatively new technology for Canada, constructed wetlands are sometimes misunderstood. The pages in this section give you an overview of the technology, teach you how the science behind constructed wetlands for wastewater treatment works, and give you an opportunity to take a virtual tour through a wetland. Think of it as 'Constructed Wetlands 101' ...
Overview
If there was a formula to explain exactly what a constructed wetland is, it would look something like this:
- Constructed Wetland / comb./ 1. n.
A designed and managed system of saturated substrates, wetland plants, microbial communities and water that simulates the functioning of natural wetlands for human use and benefits. Syn: Managed marsh, artificial wetlands, treatment wetlands, engineered ecosystems.
Just the Basics
In brief, a constructed wetland is a wastewater treatment facility. Constructed wetlands are designed, built and operated through human technology but are based on the processes that occur in natural wetlands. Constructed wetlands are complex, integrated systems in which water, plants, microorganisms, the sun, substrate and air interact to improve water quality. By attempting to optimize the physical, chemical and biological processes of the natural wetland ecosystem, constructed wetlands are both natural and engineered systems.
What Are They Used For?
If properly designed and built, constructed wetlands can effectively remove pollutants associated with residential, municipal and industrial wastewater and stormwater.
Constructed wetland systems are especially efficient at removing contaminants such as BOD, suspended solids, nitrogen, phosphorus, heavy metals and even complex organic molecules.
Constructed wetlands are used in a variety of situations to treat:
- sewage for single households and small communities
- residential and municipal effluent
- industrial wastewater tertiary treatment
- agricultural wastewater (milkhouse wash water, nutrient-rich runoff)
- aquaculture waste
- stormwater runoff
- acid mine drainage
- landfill leachate
See our project registry for examples of this technology in Canada.