The Helwick helps protect the very exposed South-West Gower beaches from the full force of the waves. When the wave height is 2m or above, there is extensive visible wave breaking along the Helwick for a couple of hours either side of low water. This obviously acts to dissipate wave energy at low tide - this is when the beaches shoreward of the bank (Mewslade Bay, Fall Bay) are exposed to breaking waves. On higher tides these beaches are covered by the tide
and the waves break against clffs. These beaches are in an AONB and I would describe their sand cover as a 'thin veneer'. Obviously if the dredging lowers the ridge crest or extent, there will be less breaking (dissipation) on the bank, and larger waves will reach the beaches and cause erosion. Ironically this eroded material may end up on the bank and help to maintain the bank volume!

Apparently Port Eynon Bay (a couple of miles downdrift) shows considerable erosion, whereas the next bay - Oxwich - does not. This is simply because Oxwich faces SE away from the main waves and is in a different transport cell.

In order that the South-West Gower beaches are not eroded, it must be shown that the dredging will NOT reduce EITHER the ridge crest elevation OR the extent of the shallow area of the ridge."

Dr Paul Russell*
Principal Lecturer in Physical Oceanography
Institute of Marine Studies
University of Plymouth

* Author of 30 papers in international scientific journals and presently participating in over £1 million of research grants on breaking waves, nearshore currents and coastal sediment transport.

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