Process options for a sewage lagoon in Arctic Canada
|Theme||1. Environmental protection|
|Session Name||1.5 Sanitation in small Arctic communities|
|Author(s)||Kenneth Johnson (National Research Council, Canada)|
The existing sewage lagoon for the community of Fort Resolution, Northwest Territories is a facultative/infiltration process consisting of seven cells of various sizes linked by channels. Detention in the lagoon, and the infiltration process through the sandy soil provides treatment to a secondary level of treatment. In 2008 a waste management planning study recommended the construction of a new lagoon to meet the twenty-year wastewater generation demand. The report presented 2 options: a facultative infiltration process, and a retention process. Based upon the ongoing concerns with the performance and operation of a facultative infiltration lagoon system, and regulatory feedback, a decision was made to advance the design of a lined retention lagoon. Preliminary engineering was advanced on the new lagoon system in 2017, and a comparison of various configurations of a retention lagoon were considered. These configurations included a single lined cell, two lined cells with primary and secondary cells, and three lined cells with a polishing filter. The three cell configuration was a recent process innovation proposed as a result of a comprehensive research program on Arctic lagoon systems. Based on cost and the anticipated performance information on the lagoon systems, the two-cell lagoon process configuration proposed was confirmed to be the most appropriate option for Fort Resolution. The capacity of the proposed sewage lagoon is 32,000 m3 based on the sewage generation projection. The design and construction of the two cell process configuration is scheduled to be completed in 2018.