Modeling surface waves and tide–surge interactions leading to enhanced total water levels in a macrotidal bay

Large waves and storm surge generated by powerful storms can have detrimental impacts on coastal areas. The Gulf of Maine and Bay of Fundy system in the Atlantic Ocean is a particularly dynamic environment where storm surge can synergistically combine with the large tides to yield serious impacts on low-lying coastal areas. In this study, impacts from Hurricane Arthur in 2014 were investigated with observations and numerical simulations using a coupled hydrodynamic-wave model. The results indicate that the storm generated significant wave heights up to 5 m in the Gulf of Maine and a storm surge of over 0.5 m in coastal areas in the Upper Bay of Fundy, however this surge occurred during the neap tide with no associated flooding. Additional simulations, including a historically important event called the Saxby Gale of 1869, were also simulated. This powerful storm occurred during a perigean spring tide, and the model results indicate wave heights of over 10 m and storm surge of over 0.7 m that caused significant flooding. The results indicate that a well-timed tropical cyclone during a high spring tide has the potential to create a storm surge that could overtop existing dyke systems, causing extensive flooding and damage.