Wastewater Management: Northern Solutions for Northern Conditions

Background and Challenges

Effective wastewater treatment is fundamental for environmental and human health protection. In the North, this can be challenging: the extreme climate eliminates the possibility of using several systems that are common in southern Canada, and the remoteness of the region and lack of road access to many communities increase costs and make timely maintenance, repairs and monitoring difficult.

Despite these challenges, wastewater treatment and sanitation practices in the North have steadily improved since the 1960s, when many northerners moved off the land into centralized communities with government-supplied housing. Over the ensuing decades indoor plumbing with holding tanks and trucked collection service of household wastewater have replaced “honey buckets” (toilets that contain waste in disposable plastic bags) and outhouses (Johnson, 2008). Above-ground or shallow-buried pipes, known as utilidors, were installed in some communities. These changes have led to considerable public health improvements in the North, where sanitation related disease rates had been up to 40 times higher than the rest of the Canada (Christensen, 2015; Robinson & Heinke, 1990).

Wastewater contaminants can be removed either mechanically, or passively using natural processes in wetlands or marine waters. To treat domestic wastewater most northern municipalities use passive systems, which are as the construction and energy costs are relatively low and they require minimal operation and maintenance – an important consideration for the North where there are few trained water and sanitation engineers and technicians. Recently however, more stringent effluent treatment standards, known as the Wastewater Systems Effluent Regulations (WSER) have been proposed for Canadian municipalities (Canadian Council of Ministers of the Environment, 2009; Jamieson et al., 2015).

There is concern among northern governments that the regulations, which may be suitable for most southern regions, are not appropriate for the North. Territorial representatives, Inuit organizations, and other parties have expressed the opinion that the proposed regulations do not reflect conditions in northern communities (Inuit Tapiriit Kanatami & Johnson, 2008; Lam & Livingston, 2011). They believe that such rigid targets are unrealistic and place an unnecessary burden on communities, in essence forcing them to divert funding from other needed infrastructure projects in order to construct and operate costly mechanical systems that are prone to breakdown and failure in Arctic conditions. They are advocating for the development of more realistic, northern-specific targets that are higher, yet still meet the goal of the WSER, which is to provide ample environment and human health protection.

Research and Potential Solutions

The WSER do contain some recognition of the unique conditions in the North, and as such, have provided a window for Arctic jurisdictions to investigate the effectiveness of their current wastewater systems and what risks the effluent discharged poses to the local environment (Canadian Council of Ministers of the Environment, 2009). In response, Northern communities and governments have partnered with university researchers and engineering consultants in various working groups to study current northern wastewater systems and propose appropriate improvements.

One such partnership was formed between Nunavut’s Department of Community and Government Services and Dalhousie University’s Centre for Water Resources Studies. This group conducted benthic (bottom-dwelling) invertebrate surveys – a common method of measuring the effects of sewage pollution – in the marine waters near treatment systems in five communities, using dye tracer studies and water quality monitoring to corroborate the results. The study found that the volume of effluent being discharged, rather than the quality, had the greatest effect on the magnitude of environmental impact. The assimilative capacity of the marine receiving waters was also a key determinant. For instance, in small communities of 1500 people or fewer that discharge less volume, the impact was limited to within 50 to 150 metres of the effluent discharge location; however in Iqaluit, a larger community with a continuously discharging mechanical plant where effluent is released onto exposed tidal flats, the impact was detected at distances up to 500 metres (Krumhansl et al., 2015).

Studies of the treatment ability of ponds and wetlands have also been conducted by Dalhousie University as well as Fleming College. They have demonstrated that in the Arctic these passive systems can treat wastewater effectively. However, design guidelines need to be refined to account for climate and the short summer treatment season (Chouinard et al., 2014; Hayward et al., 2014; Ragush et al., 2015; Schmidt et al., 2016; Yates et al., 2012). Dalhousie University is continuing to work with Nunavut communities to assess the potential exposure and health risks of operating wastewater treatment systems near local fish and wildlife harvesting areas (Daley et al., 2015).

While it appears that passive treatment systems are best suited for the North it is still possible to improve the operation of the small number of mechanical systems currently in use (there are only six in Nunavut, Northwest Territories and Yukon combined). Efforts are underway to adapt technologies primarily used to diagnose problems with drinking water treatment systems in order to overcome similar challenges associated with mechanical wastewater treatment systems in Northern communities. For instance, recent upgrades to cellular communications technology in the North have enabled the Government of Northwest Territories Department of Municipal and Community Affairs to provide more efficient support to local operators. From the central office in Yellowknife, department engineers are now able to connect remotely to treatment systems computers in many of the smaller and less accessible communities across the territory. They can review system data logs, assess problems and provide immediate advice to the local operator regarding adjustments or repairs. This has reduced the number of costly fly-outs to troubleshoot problems, and the time that systems are shut down when malfunctions do occur (Hazenberg, 2015; Rohner, 2016).

Similarly, the DeRISK Centre at the University of Alaska Anchorage has developed a graphical user interface that allows treatment system operators experiencing problems to quickly search for neighbouring communities with similar systems, enabling them to make repairs more quickly by sharing information, expertise and supplies (Ahlrichs et al., 2016). The State of Alaska has launched the Alaska Water Sewer Challenge, which invites teams to submit design proposals for innovative and cost-effective water and sanitation solutions. As opposed to the centralized treatment systems used in the Canadian Arctic, which serve an entire community, many of the finalists in Alaska have opted for decentralized, individual treatment systems that can be added to existing homes or housed in a conventional shipping container adjacent to the home (State of Alaska, 2015).

An emerging issue in northern wastewater treatment is how to deal with the pharmaceuticals being released into the environment. Pharmaceuticals have low biodegradability and long persistence in cold waters, and antibiotics are a particular concern because they can disrupt aquatic organisms like fish, or accumulate in the food chain. Solutions may lie outside the capabilities of existing treatment systems. Since most pharmaceuticals residues found in wastewater originate from human excreta, separating toilet waste from the rest of wastewater (e.g. bathing water, laundry water) through the use of dry toilets or other source separating technologies may be a cost-effective option for Arctic communities (Gunnarsdottir et al., 2013)

Northern Wastewater Management Associations and Conferences

The Northern Territories Water and Waste Association is a group of experts from government, industry, academia and communities who meet annually to discuss the latest issues in wastewater management in the Canadian Arctic (NTWWA 2016). These issues are not unique to Canada. From April 12-14, 2016 the Arctic Technology Centre in Sisimiut, Greenland, hosted an international conference on Sanitation in Cold Climate Regions. Canadian representatives from several universities as well as the National Research Council exchanged information on shared challenges and potential solutions with their counterparts from Greenland as well as Alaska, Denmark, Norway, Sweden, Finland, Iceland, Russia, and the Faroe Islands, among others. All agreed that wastewater management in Arctic regions requires approaches that ensure environment and health protection but are appropriate for northern conditions. Presently, this is best accomplished with simple yet robust systems. However, since conditions in the Arctic are changing rapidly, it is also important for communities and other stakeholders to be aware of emerging challenges and new innovations.

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