We worked closely with MacDonald Hydrology Consultants Ltd. to complete preliminary flood modeling for 16 km of the Elk River between Hosmer and Fernie, BC for the Elk River Watershed Alliance. Using detailed LiDAR and supplemental bathymetric survey, cross-sections were cut at approximately 50 m intervals for import to HEC-RAS. Important hydraulic features such as levees, bridges, culverts, and the overflow from the main channel to a tributary creek were defined in HEC-RAS.
The 1:200 year, 1995, and 2013 event flood extents were modeled and exported to GIS for the preparation of floodplain visuals. Results were compared with anecdotal information and photos from past events from the client. Models were also built to simulate an additional berm and relief culverts to determine at a high level if additional construction could alleviate some flooding in Hosmer.
Floodplain delineation results were included in a publicly accessible database format, available at the link below:
MacDonald Hydrology Consultants