10/08/2012

Cardigan Bay councils plan for rising sea levels


A consortium of local authorities are proposing that the sea be allowed to break through at Tanybwlch beach just South of Aberystwyth and allowed to flood into the Ystwyth valley.

The Cardigan Bay Coastal Group’s Shoreline Management Plan accepts that maintaining a sea defence at Tanybwlch (above) is unsustainable in the long-term due to rising sea levels. It proposes allowing the sea to eventually flood into the Ystwyth Valley, joining with the river Ystwyth in the direction of Rhydyfelin where flood defence work may eventually need to take place.

The plan would take the mouth of the Ystwyth back to its original state of a broad tidal estuary. In the 18th century the river was diverted into the mouth of Aberystwyth harbour by the placing of large boulders across the estuary and digging a trench through a rocky bar along the foot of Pen Dinas. It is not thought that letting nature take its course will have a significantly detrimental effect on the harbour which is only dependent on the river Rheidol.

For the rest of Aberystwyth, the plan proposes a ‘hold the line’ approach to the sea, envisaging shoring up existing defences, especially in the Trefechan area. The report raises the long-term possibility of ‘re-charging’ Aberystwyth beaches and even land reclamation in order to control the shoreline.

Further north, the plan envisages the village of Clarach slowly retreating inland, the loss of Borth golf course to the sea in the long-term and even discusses the eventual need to re-locate the railway line.

It is sobering to see the authorities now coming to terms with the inevitability of rising sea levels and making plans accordingly.

The West of Wales Shoreline Management Plan is a huge document put together by the five county councils along the coast together with the Welsh Government and other involved organisations.

Image source: http://www.geograph.org.uk/photo/846582