Just south of the Arctic Circle in the small Nunavut hamlet of Chesterfield Inlet—or in Inuktitut, Igluligaarjuk—a sewage truck dumps its potent—smelling load into a shallow hole in the ground about three kilometres from the community. The sewage seeps out of this natural depression in the bedrock and flows through a 900-metre stretch of natural tundra wetland before entering the ocean.
While this sewage disposal method may seem undesirable, especially to people accustomed to underground sewage collection systems and industrial wastewater treatment plants, the Chesterfield Inlet wetland has been naturally filtering wastewater with a fair degree of success for at least the last 15 years. The outflowing water looks clear, with no visible colour or suspended particles and little to no algae (the litmus test for excess nutrients like phosphorus or nitrogen).
Chesterfield Inlet is not the only community that uses this method-most communities in the North use lagoons and wetlands to treat wastewater, primarily because local conditions and constraints have meant that employing conventional sewage treatment plants (STPs) has been largely unfeasible. This is because STPs —which clarify, filter and disinfect wastewater until it is considered safe for humans and the environment— have significant limitations, even though they are taken for granted as the best way to treat municipal wastewater.
STPs require a huge sum of infrastructure capital, constant operation and maintenance funds, a highly trained work force, and, in many cases, constant supervision or a sophisticated computerized monitoring system. Further, they are energy-intensive, use various reactive chemicals and are only cost effective for larger communities. This makes them a poor fit for most of Nunavut for many reasons: its geography, a small and sparsely distributed population, new and developing institutions, limited community capacity, financial constraints, and challenges surrounding the relationship between Inuit and non-Inuit ways of life in the context of colonialism and its lingering effects. Finally, permafrost alone can make construction and operation costs prohibitive.
The use of wetlands to treat wastewater in the Arctic started as somewhat of an accident. Limited options meant that many communities were forced to dump their sewage directly onto the tundra, and soon local operators discovered that during the summer months the wetlands were able to effectively filter the wastewater. This isn’t a new discovery—as discussed in Scott Wallace’s “Constructed Wetlands”, the capacity of wetlands to treat wastewater has been long understood, and the application of this treatment method has been gaining acceptance around the world in recent decades.
There has been some skepticism, however, regarding the ability of wetlands to function in cold climates. Treatment wetlands improve water quality—including removing pathogens (such as E. coli and fecal coliform bacteria), excess nutrients and other types of contaminants—by taking advantage of complex natural wetland processes. A long Arctic winter with sub-zero temperatures and minimal sunlight means wetlands are a summer-only solution. For the rest of the year, wastewater must be stored in lagoons. Also, the ad hoc way in which the use of treatment wetlands developed in the Arctic, and an accompanying lack of formal research, means that the design and operation of wetlands varies between communities—and so does their success. However, wetlands like the one in Chesterfield Inlet demonstrate that this treatment method can be effective even in extreme climatic conditions.
Besides being functional and inexpensive, treatment wetlands are intuitive, accessible, and congenial with their surrounding environment. In some Nunavut communities, a running joke amongst hamlet foremen is that the treatment wetlands are the greenest part of their hamlet. In fact, the United Nations Environment Programme (UNEP) has recognized treatment wetlands as an appropriate and environmentally sound technology, and has been facilitating their application to improve quality of life in areas like water and sanitation, while protecting the environment. According to Vicente Santiago, a water officer with UNEP’s International Environmental Technology Centre, Nunavut and other places benefit from a wastewater treatment approach that is uniquely adapted to and complements each community’s local conditions, including social aspects. With appropriate research culminating in design and use guidelines, treatment wetlands can continue to provide a viable alternative to conventional sewage treatment plants in the Arctic.
The Centre for Alternative Wastewater Treatment (CAWT) at Fleming College in Lindsay, Ontario is contributing to knowledge surrounding Arctic treatment wetlands through an International Polar Year (IPY) project. The CAWT was awarded $700,000 over four years in IPY funding by the federal government to do groundbreaking research on Arctic treatment wetlands.
While wetlands are currently being used for sewage treatment in many Northern communities, there is still a lack of knowledge about how to best design wetlands to suit Arctic conditions and meet changing community needs, especially as populations grow and become more urbanized.
The purpose of the project is to help address the growing need for environmentally sustainable technologies and resource management practices by contributing to safe, practical and low-cost wastewater solutions. The research activities are taking place in the Kivalliq region of Nunavut, and are focusing on:
- Describing in detail the efficacy and performance of existing wetland treatment systems;
- Developing and validating a prototype design specific to Arctic needs; and
- Training and educational initiatives for community members and technicians.
Collaboration and partnership are key components of each activity. The data collected will be used to develop guidelines for treating wastewater with wetlands in the North, which could be used to help inform proposed new regulations under the federal Fisheries Act. Through the training component, communities will be engaged in environmental monitoring and management of this “living” technology. This research initiative has the potential to make significant contributions to the health of Northern peoples and the stewardship of water resources.
Brent Wootton is the director and senior scientist at the Centre for Alternative Wastewater Treatment at Fleming College.
Agata Durkalec is the International Polar Year project coordinator at Fleming College.
You make some excellent points about how conventional STP’s don’t always fit in the Arctic environment… especially for smaller communities. Have you considered the many small footprint, low cost, low maintenace pre-treatment systems (UV, RO) that could be employed for use on the effluent prior to discharge to give the wetlands attenuation process a head start?
Please let us at Canadian Water Treatment magazine know when findings from your IPY Project are available – we’d love to come to Chesterfield Inlet to see your work first hand and report on it to all Canadians!