I have just spent a week’s holiday on a small island in the North Sea enjoying the coming and going of high tide and low tide.
Groins / groynes like this one were made of wooden posts in former times. Nowadays they are rather made out of concrete or stone. In the ocean, groynes create beaches or prevent them being washed away by longshore drift. In a river, groynes prevent erosion and ice-jamming, which in turn aids navigation. Ocean groynes run generally perpendicular to the shore, extending from the upper foreshore or beach into the water.
Groins / groynes like this one were made of wooden posts in former times. Nowadays they are rather made out of concrete or stone. In the ocean, groynes create beaches or prevent them being washed away by longshore drift. In a river, groynes prevent erosion and ice-jamming, which in turn aids navigation. Ocean groynes run generally perpendicular to the shore, extending from the upper foreshore or beach into the water.
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Sig Nordal 