Impacts of the February 9, 2013 storm along the Atlantic Coast of Nova Scotia

Abstract

Markers established at select coastal locations along Nova Scotia facilitate repetitive observations of physical shoreline changes caused by specific storms and a comparison of the impacts by different types of storms on shoreline stability. Following the storm of February 9, 2013, field observations of physical impacts were completed at five beaches along the Eastern Shore of Nova Scotia and information on storm impacts was gathered from local contacts at other locations farther along the Atlantic coast. Wave and tidal observations during the storm were provided from a wave gauge operated offshore of Halifax Harbour and from tide recorders operated by the Canadian Hydrographic Service, in Halifax Harbour, Yarmouth and North Sydney. Field observations were restricted to the use of ground photography, a hand-held GPS recorder and tape measurements from beach line markers. Detailed cross-shore surveys following the storm were not completed. Flood and wave-run-up elevations onshore (CGVD28-Geodetic Datum) are based on the most recent survey completed at each site before the storm. The storm on February 9, 2013 caused elevated water levels of 1.93 m (GD) just after high tide at Halifax but occurred closer to low tide in Yarmouth and North Sydney. The highest still water flood level observed was 1.1 m (GD) along the backshore lagoon at Conrads Beach. Wave runup reached elevations commonly of 3.5 m and as high as 3.8 m (GD) along higher pebble-cobble beaches. Waves scoured the base of the highest pebble-cobble beaches and only overtopped lower barrier beaches and built the beach crest higher. Along sand beaches, waves scoured the upper beach and lower foredune. The duration and intensity of waves generated during the storm was not sufficient to force waves long distances across coastal dunes nor to cause significant damage to coastal infrastructure such as beach access stairs. Farther away from Halifax, local observers along the Atlantic coast of Nova Scotia reported reduced impacts from the February 9 storm because of the presence of snow, freezing rain, shorefast ice and a more favourable wind direction.