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COASTS. PROTECTION METHODS. Storm waves attacking a sea wall. At the end of winter’s storms, much work is done to improve or repair sea defences. Note the groynes in the background. Rip raps and a sea wall. Hard engineering in progress. The rock Groyne at Mappleton. Sea Walls & Groynes.
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COASTS PROTECTION METHODS
At the end of winter’s storms, much work is done to improve or repair sea defences. Note the groynes in the background.
Sea Walls & Groynes • Erosion rates at Aberystwyth in West Wales are not very high but the damage done by pebbles in waves can be enormous. The hard sea wall (concave) is supported by a wooden groyne.
Cromer’s sea defences GROYNES
Revetments • These are wooden barriers with louvre-like slats across them. They trap sediment behind them – it falls through the slats – and water is able to drain away easily. • These at Cromer, Norfolk, have not stood up well to wave attack.
COASTAL PROTECTION • Rip Raps • These are large boulders placed at the base of cliffs or sea walls to act as additional protection against wave attack. These are at Sheringham, Norfolk
Off shore bars/reefs • Bournemouth – Countryfile film • Breaks waves earlier • Additional benefits – surfing tourism
Here in Porthcawl a concave sea wall and rip rap groynes have been put in place. However, arguably the best natural form of defence is a large beach – effective & looks natural.
In many areas natural sea defences in the form of sand dunes are very effective. To protect these at Ynyslas from excessive erosion from walkers, a boardwalk has been constructed.