In 2023, NHC was engaged by the Government of the Northwest Territories to develop flood hazard maps for the communities of Hay River, K’atl’odeeche First Nation, and Fort Simpson. For Hay River and K’atl’odeeche First Nation, flood hazard maps are to be developed for two ice jam scenarios and one open water scenario; and for Fort Simpson, flood hazard maps are to be developed for two ice jam scenarios. This study is being conducted in accordance with the Canadian Federal Flood mapping Guidelines Series, and the Northwest Territories Ice Jam Flood Mapping Guidelines (which NHC developed in 2023).

The hazard maps will advance the state of flood mapping in the Northwest Territories. It is intended that the flood hazard maps will be used for community infrastructure planning and other flood mitigation measures, and emergency preparedness. The flood maps would be of a sufficient standard that they could in the future be adopted by the GNWT as regulatory flood maps. The work follows a detailed engineering methodology to develop flood hazard models and mapping for the communities of Hay River, K’atl’odeeche First Nation on the Hay River (~ 56 km length of river) and Fort Simpson (~ 30 km length of river). These are major rivers in Canada’s north. The Hay River study basin is approximately 52,000 km2 and the basin area reporting to the confluence of the Liard and Mackenzie rivers at Fort Simpson is approximately 1,300,000 km2.