Barton On Sea Case Study

Barton on sea is situated in the south coast of England between Lymington and Bournemouth. It is well known coastal area as it was the first place to try out rock groynes. The top of the cliff face is made from sand with gravel within it, and the bottom of the cliff where it’s starting to slump is made from clay which is porous and does not let water in easily unlike sand which is why we can see large amounts of coast erosion as the sand and gravel have pushed back so far.

Barton on sea has had many problems with coastal erosion as they have eroded away at an average of 1 meter per year and several buildings have been lost. Hydraulic action is just one example of the erosion process that is taking place as the force of the waves and sediment
knocking against the cliff face is causing the cliffs to erode. Also there are a type of weathering which effect the cliff face which is physical weathering where the water from the sea slips into the cracks in the cliff and then freezes and expands therefore making the cracks larger.

The way Barton on sea chose to manage the area was to put in sea defences to try to reduce the impacts of coastal erosion.
16 timber groynes and a flexible timber revetment backed by rock fill were put in over a stretch of 1.8km over the east Barton frontage. A cliff drainage system was also put in place to try reducing the impacts of coastal erosion aswell.

There are two sea defence types as hard and soft engineering were put in place at Barton to help reduce the strength of the waves as revetments, groynes and sea walls are types of hard engineering and the beach drainage system was put in place to dissipate the waves energy again reducing the impacts of coastal erosion.

It was impossible to show a cost/benefit ratio for spending 1.3 million to protect low value land used for holiday accommodations. The cost for all of the sea defences range on how effective they are and how much work is needed for them to be put in place as hard engineering is usually more expensive and takes more time and effort to put in place. There are very good benefits to this though as putting in groynes and placing drainage systems in stops the waves from hitting the cliffs with such a great force and also stops sediment from hitting the cliff face and moving along the beach (longshore
drift).

The 4 options that Barton on sea has to offer are; Do absolutely nothing about the coastal erosion and let the cliff face recede naturally; manage how far to a certain extent the cliff is going to be eroded (managed retreat), Hold the existing line by keeping the sea defences stable and fully functional, or advance the existing line by placing even more sea defences within the coastal area to try to reduce as much erosion as they can but these options do come with positives and negative as the more they try to stop coastal erosion the more money they will need to invest in to it.
The less they spend on trying to stop coastal erosion the more the cliff will actually erode.

The actual solutions that Barton on sea has taken are; to improve and maintain the existing coast protection works; create safe and convenient public access to the beach; work with Hampshire city council to include the cliff top footpaths in the Solent way. Another action they have chosen to take is to refuse to permit drainage of surface water to soak ways within a zone extending approximately 400m inland from the cliff edge where ground water flow can contribute to cliff
instability.

In the longer term the District Council will seek to improve the appearance of the cliff face by encouraging natural vegetation to re-establish, and by taking positive action to replace previously existing species that have been removed over the years.

Generally, Barton on sea is trying to deal with this issue to the best of their resources but there are other problems that they have to think about such as money. The current protection is helping a lot with the erosion as it is but they need to maintain the groynes and revetments better as they were built over 50 years ago.

I feel that the costs for the coast to be fully protected would not be beneficial as they are losing 1m per year off land as it is only taking away holiday accommodation land, they should spend the money elsewhere on something that could re generate even more money then invest it on something that can be more beneficial to the coast as the ratio of benefits to costs are low.