Floodplain maps are important tools to help First Nations and local governments make informed decisions related to land use, emergency preparedness and flood response. Detailed floodplain maps are currently in progress for the Nicola and Coldwater Rivers in Central British Columbia (BC) as part of the Provincially and Federally funded Flood Hazard Identification and Mapping Program (FHIMP). These rivers flow through the City of Merritt and several Nlaka’pamux and Syilx First Nations communities, including Nooaitch, Cook’s Ferry, Shackan, Upper and Lower Nicola, and Coldwater Indian Bands. Many of these communities were significantly impacted by the November 2021 atmospheric river (AR) flood event. Incorporating the traditional knowledge and experiences of communities that lived through recent extreme events is an important part of the study. As well, sharing of resources across the Nicola Valley watershed, often through data sharing agreements, on items such as bathymetric surveys, hydrologic and climate change analyses, hydraulic modelling, lidar and orthoimagery acquisition and quantitative analyses of geomorphic change significantly improved the study outcomes. Collaboration with other practitioners and decision makers in the watersheds helped in the development of high-quality, standardized and consistent floodplain maps and advanced a shared source of flood-related knowledge in the watersheds.
