If a coastline has groynes installed perpendicular to the shore, which consequence follows for sediment distribution due to longshore drift?

💡 Explanation

Groynes disrupt longshore transport, because they trap sediment on their up-drift side, which depletes the sediment supply down-drift causing increased erosion. Therefore, the answer is accretion up-drift, erosion down-drift, rather than uniform distribution because the sediment transport is interrupted.

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