2019 CSCE Annual Conference - Laval (Greater Montreal)

2019 CSCE Annual Conference - Laval (Greater Montreal) Conference

Wave Run-Up Contributions to Coastal Flood Hazards in New Brunswick

Mr. Enda Murphy, National Research Council of Canada
Mr. Jasmin Boisvert, New Brunswick Department of Environment and Local Government
Mr. Reid McLean, NBELG
Dr. Vahid Pilechi, National Research Council of Canada
Mr. Julien Cousineau, National Research Council, Canada
Dr. Laxmi Sushama, McGill University
Mr. Zijian Liang
Dr. Andrew Cornett, National Research Council (Presenter)

New Brunswick’s coastal communities and civil engineering systems are vulnerable to flooding associated with tides, extreme storm surges and wave events. Coastal flood hazards and risks are projected to increase over time, as a consequence of urbanization and climate change effects, including relative sea level rise. New Brunswick’s Flood Risk Reduction Strategy (2014) and Climate Change Action Plan (2016) call for the renewal and expansion of the province’s existing set of coastal and inland flood hazard maps. The Coastal Flood Hazard Mapping project aims to develop new maps for approximately 2,270 linear kilometers of the New Brunswick coast.

Initial project tasks focused on establishing future extreme water levels for fourteen identified quasi-homogenous coastal flood hazard zones in New Brunswick. This excluded allowances for wave-related contributions to coastal flood hazards, such as wave run-up on the shore. A new, regional wave run-up study was conducted to address this data gap, and to provide representative extreme wave run-up heights for 614 zones along the New Brunswick coast. Zones were identified and classified according to extreme water level characteristics, wave exposure, shore type and gradient. The study involved statistical analyses of offshore wind and wave hindcast data, numerical wave transformation modelling to evaluate nearshore extreme wave conditions, and a systematic approach to calculating extreme wave run-up heights for each zone.

Nearshore extreme wave parameters and wave run-up height data generated by the study will be incorporated in a publicly accessible, web-based map application, which will inform coastal flood risk management and climate change adaptation efforts in New Brunswick. Further, exploratory research is underway to investigate the potential impacts of climate change on the nearshore extreme wave conditions in the region.