Re: soft-engineering, Barton-on-sea
Rachel Oakley (rido196@soton.ac.uk)
Thu, 11 Mar 1999 11:11:08 GMT
The sustainable strategy you advocated for the protection of the coast at Barton-on-sea was soft engineering options such as beach replenishment and groynes. I beg to differ with you Jenny.
Groynes are present along the south coast especially at Sand Down, Avon Mouth, Highcliff and Barton-on-sea. Groynes effectively reduces long shore drift of sediment at Highcliff and Barton-on-sea but have done nothing to prevent the slumping and crumbling of the cliffs into the sea. The only structures protecting the housing at Barton-on-sea are hard engineering structures in the form of large concrete blocks. These sea defences are parallel to houses and accumulate any long shore drift. A terminal scour is created next to the sea defences and interstitial erosion is prominent along this stretch of the coast. Thus the undeveloped land at Barton-on-sea is surrendered to the sea. This is unsustainable as the soft eocene clays and sands that comprise the suburban retreating coast are retreating at a rate of 0.25 - 2m a year (Dr Ian West).
Evidence that the soft engineering strategies are not working to save the coast line at Barton-on-sea can be seen as you walk along the cliffs by the golf course. In September 1998 I was surfing at Barton-on-sea and had a particularly bad day in the surf because I was preoccupied watching the cliffs. Large chunks of the near vertical cliffs were divorced and tumbled down to the beach following heavy rainfall.
The soft engineering strategies employed at Barton-on-sea and Highcliff have so far done nothing to arrest the slumping and collapse of the cliffs. Last year out surfing at Highcliff I nearly tripped on a chimney stack lying on the beach. It had remained high on the cliff many years after the house it belonged to was lost to the sea (Rachel Oakley 1999).
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