Water Resources Award of Excellence
Whapmagoostui Cree First Nation Drainage Master Plan CIMA+
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Specifying local infrastructure The project’s success to date demonstrates the relevance of combining 44
CANADIAN CONSULTING ENGINEER
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Retention chambers were installed to collect sediments and replenish the groundwater table.
drainage methods adapted to local northern conditions with state-ofthe-art hydraulic simulations, taking into account climate change in calculating requirements. Infrastructure was designed according to the versatility of locally available materials, their weight, their durability and the capacity of local equipment to manipulate the drainage system’s components. By way of example, rain outlets with dissipation manholes were specified along the Great Whale River’s shore. These needed sufficient capacity to carry water away and withstand tides and ice movements, but since there was no ad-
“An example of smart design and engineering, with the right technology to meet the community’s needs.” - Jury
equate equipment to lift the manholes, CIMA+’s simulations led to reducing their diameter before installing them using local equipment. Design and engineering work had to consider the budgetary constraints associated with short seasons, construction methods, materials and transportation costs by boat billed according to weight and volume. The local geology, characterized by an appreciable thickness of loose, sandy soil, allowed for a design that would replenish the groundwater table. To limit the transport of sediments toward the rain outfalls, retention chambers were added to the
PHOTO COU RT E SY C I M A+
he Whapmagoostui Cree First Nation is exposed to extreme meteorological and climatic events. In this isolated community of approximately 980 inhabitants, the increasing frequency of heavy rains in the fall and spring, combined with snow melt, causes a substantial accumulation of runoff water in certain areas, which impedes pedestrian and vehicle traffic, in addition to accelerating the deterioration of gravel roads and causing damage to foundations and infrastructure already subject to freeze-thaw conditions. The Cree Nation Government (CNG) commissioned CIMA+ to create a drainage master plan for this community, with the work to be carried out by the members of the Cree Nation. This project is the first of its kind in Nunavik, north of the 55th parallel, accessible only by plane or boat. The solution was developed through a six-stage master plan, phased from 2016 to 2022. The 2018, 2019, 2020 stages have been completed and are already operational.
September/October 2021
2021-10-18 10:14 AM
