These are human made structures that are in the water and run perpendicular to the shoreline. The large rock jetty at Port Burwell was built about century ago to protect the harbour from the worst of the waves that caused problems for the ships using the port, primarily the |S. S. Ashtabula. The side effect of the jetty was to accumulate migrating sand on its west side thereby greatly increasing the size of the beach at what is now the Port Burwell Provincial Park.
The groins that once were at the tip of the Long Point Spit were built to capture sand and protect the spit. They can be seen in a aerial photograph on page 179 of Living with the Lake Erie Shore. When were they built and how long were they there?
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