Environmental and social benefits of improved handling and disposal of black wastewater in Greenland

Wastewater collection and treatment is difficult in arctic climate due to, i.e. permafrost and cold climate. Currently all toilet wastewater (blackwater) in Greenland is discharged untreated, mainly to the sea. Water from bathing, washing and kitchen (greywater) is usually not collected and is discharged above ground, next to the dwelling, even in the cities. Due to the lack of piping systems bucket toilets for collection of excreta are common. The bucket toilets and the greywater handling can pose health threats to the people and improved systems are needed. The current wastewater handling in Greenland causes visual contamination of the coast near many towns and settlements. Furthermore the nutrients in the wastewater may cause local eutrophication where the water exchange is poor. Another and maybe more serious consequence of discharging untreated wastewater into the arctic waters are organic chemicals including medicine residues. Such compounds may accumulate in the food chain, can act as endocrine disruptors, and are shown to promote formation of bacteria resistant to antibiotics. In addition to the environmental and health issues the current practice of wastewater handling in Greenland can be harmful to the image of Greenland as being a clean country with an unspoiled nature that is important since tourism is a fast-growing industry. The nature in arctic areas is more vulnerable to environmental contaminants because of low temperatures, lack of nutrients and extreme seasonal variations in light. It is difficult and expensive to treat wastewater in Greenland by traditional methods due to natural conditions and settlement patterns. Alternative methods are therefore needed. One of the options is to treat the excreta separate from the greywater, and introduce modern composting toilets or low flush toilets with collection at the household level and improved greywater treatment. This will improve the indoor and outdoor hygiene and thus status for the families. The blackwater can be sanitized and converted to small volumes of soil amendment and fertilizer and used in e.g. greenhouses or agriculture in South Greenland. The potential for removal or breakdown of medicine residues or other organic chemicals is also larger in an intense thermophilic composting process than in traditional wastewater treatment. This paper focuses on the social and environmental consequences of the current wastewater handling in Greenland and the challenges, being of social, technical or economical character, connected to implementation of new solutions that can improve public health and living standard as well as protect the environment.