Water supply and wastewater disposal in the Arctic region:
Greenland, Canada, USA (a review)

Summary

The specific features of the water supply and sanitation infrastructure in the Arctic Region are determined by the extreme dramatically changing climatic conditions, scattering throughout the vast territory of separate communities; the lack, with a few exceptions, of road communication between settlements; differences in the views of traditional and modern culture on the role of water supply and sanitation systems. The transport infrastructure involves the prevailing use of ships, aircraft and helicopters. In light of this almost all communities have autonomous systems of power supply, water supply and sanitation. Public water supply is provided only in some of the largest cities; in most cases, the water transported in tanks is stored by residents in tanks or independently delivered from water distribution points. Wastewater is either discharged untreated or passes passive purification under natural conditions organized in stabilization ponds and/or in marshy areas where self-purfication takes place due to sedimentation, biodegradation and inactivation of microorganisms under the impact of sunlight. After passive treatment the effluent is discharged into estuaries or the sea. In households of small settlements bio toilets with removable plastic bags are widely used. These bags are collected, transported and emptied at sea by municipal services, outsourcing companies or individual collectors. Recently local wastewater treatment and reuse systems have become common; monitoring of anthropogenic pollution of the natural aquatic environment is becoming regular.

Key words

water supply , anthropogenic pollution , aquatic environment , the Arctic Region , Greenland , Canadian Arctic , Alaska

Water supply and wastewater disposal in the Arctic Region:
advanced technical soltions (a review)

Summary

In Canada wastewater treatment technology has been developed for small isolated arctic communities based on the effective biodegradation of organic carbon using a combination of anaerobic methanogenic and microbial bioelectrochemical processes that provide for biomethane generation. Microbial electrochemical degradation is executed in a membrane-free flow-type reactor with a bioanode and a biocathode operating at a voltage below the threshold of water electrolysis. In laboratory-based experiments in a wide range of mesophilic and psychrophilic temperatures (5–23 °C) a high efficiency of reducing BOD₅ (90–97%) was achieved with a residual content of less than 7 mg/l. Energy consumption is 0.6 kWh/kg COD. Low energy consumption along with the production of biomethane ensures the operation of the reactor in the mode of power generation. For the conditions of Greenland a scheme of wastewater disinfection involving chemical coagulation and addition of peracetic acid, and/or ultraviolet irradiation was developed. Complete inactivation of Escherichia coli is achieved with the combined use of ultraviolet radiation (2.1 kWh/m³) and peracetic acid. Preliminary coagulation is an essential prerequisite for the effective inactivation of microorganisms. In the United States a closed water treatment scheme based on the peroxone process with reuse of water for drinking purposes has been proposed for the city of Fairbanks (Alaska). The big advantage of the closed-loop scheme is 85% conservation of the water in the system while preserving the thermal energy obtained from different water heaters. As a result the purified warm water is returned to the consumer; while less energy is required for its additional heating. In addition, the mineralization of organic substances in the oxidation process ensures the achievement of 0.7 mg/l residual COD.

Key words

wastewater , water disinfection , water treatment , ultraviolet irradiation , water reuse , the Arctic Region , preliminary coagulation , peracetic acid , peroxone process , heat energy of water , anaerobic methanogenic process , microbial electrochemical process