The status of domestic wastewater treatment in the Arctic

This paper provides a Panarctic review of the regulations, loads, and treatment of wastewater (WW) discharged in the Arctic region. WW regulation principles and practices vary across the Arctic nations, being based either on effluent quality criteria (Canada, Sweden and Cruise ships), recipient-based criteria (Greenland, Norway), or a combination of the two (Alaska, Faroe Islands, Finland, Iceland, Russia). Conventional centralized treatment, ranging from preliminary screening to advanced/tertiary treatment, is applied to 59% of Arctic WW. Natural centralized systems, including ponds, lagoons, wetlands, and infiltration systems, are used for the treatment of 5% of the WW in the region, while 16% is treated on-site, mostly using septic tanks, sometimes affiliated with drain fields, but small package plants and infiltration systems are also in use. Between 14-20% of Arctic WW is discharged without any treatment in line with the global regions with the highest WWT service levels. However, Arctic treatment systems frequently fail to meet regulations or have reduced requirements, and secondary treatment level or higher is accomplished for only 19% of the total WW in the Arctic region, compared to 86% in Europe and North America overall. Where treatment is absent or deficient, discharge of WW may contribute to the environmental degradation of receiving waters and pose the risk of exposure of local fauna and humans to chemical contaminants and pathogens. Ecosystem impacts have been described for communities with above 2000 inhabitants; however, more studies are needed. Most sludge in the Arctic region is landfilled or used as landfill coverage, also leaving risk of exposure. It is recommended to establish cross-regional collaboration to exchange knowledge and experience on solutions and practice, and to introduce an aligned legislation and monitoring framework to reduce the environmental footprint and the risk of exposure of WW in the region.