Accretion is the process of coastal sediment returning to the visible portion of a beach or foreshore after a submersion event.
[1] A sustainable beach or foreshore often goes through a cycle of submersion during rough weather and later accretion during calmer periods.
[1] If a coastline is not in a healthy sustainable state, erosion can be more serious, and accretion does not fully restore the original volume of the visible beach or foreshore, which leads to permanent beach loss.
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