FORT RESOLUTION NT - SEWAGE TREATMENT PROCESS SELECTION The Hamlet of Fort Resolution is a community of 500 people at the southern limit of the Northwest Territories of Canada. A decade ago, the community and the regulators had ongoing concerns with the sewage treatment system serving in the community. The existing sewage system was not engineered, and there were a variety of issues, including capacity, effluent quality, and discharge control.
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A single cell retention lagoon process is often used in communities in the Canadian north, the single cell system is very easy to operate, however the process performance may not consistently meet the effluent quality standards.
Fort Resolution is located near the southern border of the Northwest Territories in the Fort Smith Region of Canada
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Lagoon site
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A 3 cell theoretical system under development for Nunavut was also presented for comparison purposes, but the performance has not been verified.
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Fort Resolution is a community of 500 People and the community is serviced by trucked water ans sewer.
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The sewage lagoon is 1.5 km north of the community, adjacent to a solid waste area. A side by side comparison of various lagoon configurations suggests that a 2 cell system performs better. Optimization of the 2 cell system is achieved with an alignment of the primary and secondary cells to improve constructability.
A compilation of performance data on lagoon systems suggests that a lagoon system with a primary cell will perform considerable better that a system without a primary cell - one cell system – on the other hand the application of additional cells may not necessarily provide a significant improvement in lagoon performance.
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3 The construction elements of the lagoon include a geosynthetic line positioned on berms with 3 to 1 slopes.
13 4 Several difference configurations of a two cell lagoon system were considered, including the application of a cutoff wall in the second cell.
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A natural wetland system adjacent to the lagoon site will provide supplementary treatment for the lagoon discharge.
The sewage lagoon system includes a piecemeal sewage lagoon system with 7 connected cells.
14 5 The sewage lagoon treatment process is an exfiltration system into the existing ground profile.
6 A study of the sewage treatment system recommended the application of a 2 cell retention lagoon system process as an alternative to the the existing exfiltration system process.
The discharge from the lagoon to the wetland will be a gravity system operating for a 30 to 60 day period during the latter part of the summer.
Kenneth Johnson, Planner, Engineer, and Historian Web: issuu.com/cryofront Email: cryofront@shaw.ca Text: +1 780 984 9085 References 1. Johnson, Kenneth R. Process Options for Sewage Lagoon in Sub Arctic Canada. CSCE Annual Conference, 2018. 2. AECOM. Fort Resolution, NT Waste Management Planning Report. 2008. 3. DW Smith, Editor. Cold Regions Utilities Manual. CSCE, 1996. 4. Stantec. Fort Resolution, NT Sewage Treatment Preliminary Engineering Report. 2017.