Overtopping
Culvert, screen and outfall manual, (CIRIA C786) published by CIRIA in 2019, defines overtopping is: ‘The passage of water over a component such as a floodbank or seawall, due to wave action. Overtopping does not necessarily represent ‘failure’ of a flood defence to perform its function.’
Groynes in coastal engineering (CIRIA C793), published by CIRIA in 2020, defines overtopping as: ‘Water carried over the top of a coastal defence due to wave run-up exceeding the crest height.’
It defines overwashing as: 'The effect of waves overtopping a coastal defence, often carrying sediment landwards which is then lost to the beach system.'
See also: Overflowing.
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