HGIS: Sable Island Shallow Water Bathymetry

Coastal Zone Management

September, 1982

Shallow Water Bathymetry - Sable Island, Nova Scotia

Easterly view of Sable Island from West Light vicinity with northern dune ridge (A), extensive low sand flats (B) and offshore parallel bars.
Sable Island is situated on the Sable Island Bank some 290 km southeast of Halifax, Nova Scotia, in an extremely rough and stormy North Atlantic environment. The island is a mobile envelope of sediment which is continually being reworked and redistributed in cycle with the seasons. Large amounts o sediment are eroded and transported during winter storms. Constructive waves during summer extend the spits and shoals. The shoreline is twisted and pulled by waves from all directions. The east and west ends of the island are particularly dynamic, waxing and waning with littoral currents and wave influences.
No modern systematic and detailed hydrographic charts of the nearshore waters have ever been made for Sable Island due to the ever present surf, shifting sands, dangerous currents and other hazards to navigation and the hydrographic surveyor. Recent discoveries of oil and gas in the area have created a demand for accurate and detailed charts.
Under a contract with the Canadian Hydrographic Services, Hunter and Associates utilized airphoto interpretation to map the ever shifting shallow water and shoals around Sable Island. A detailed literature review of the sediment transport system, coastal geomorphology and marine biology was undertaken to provide the interpreter with a knowledge of the airphoto pattern elements.
The final report includes a detailed description of the sediment circulation in the nearshore and offshore areas and furthers understanding of the shifting sand and shoals in this ships graveyard of the Atlantic. Shoreline and nearshore information prepared by this study have been successfully integrated with offshore deep water sounding into the new Hydrographic Chart for the Sable Island Bank.