Sea Defences at Minehead and Their Effectiveness

Sea Defences at Minehead and Their Effectiveness
Minehead is located in the South-west of England, on the Somerset coast (as shown in pictures 1 & 2). The area of sea is subject to the second largest tidal ranges in the world, 14m. Over the years the tides have been a mixed blessing, with it?s vary fast running currents. The tides have allowed Minehead to develop into a busy seaside area with their harbour. Minedhead has also been flooded on numerous occasions, for example in 1910, 1936, 1981, 1989, 1990, 1992 and twice in 1996. [image][image] Picture 2 Picture 1 History/ Background Minehead has had some form of sea defence for several years. When the town was just a small hamlet the only protection from the sea was by a high beach, which was backed by a natural shingle and cobble ridge. However with the town growing rapidly, the ridge was gradually replaced with a masonry wall. Minehead?s harbour to the west, ?rip-rap? groynes were placed along the beach which contributed to a major loss of the beach material since the early 20th century.
The old sea wall which was under attack was suffering frequent damage, but despite all of its repairs the wall had reached the end of what was called its ?useful life.? This meant that the government and local community found that if no improvements were made to the sea wall and defences. If a storm was forecast the damage today would cost over an estimated £21 million. Picture 3 However for a new wall to replace the damaged one the problem was down to who would be responsible for its ?upkeep?. This meant that for the new wall to built the Environment Agency, West Somerset Council, Butlins and Somerset County Council had to agree to employ engineering teams and landscape architects come to Minehead to build the wall which would cost millions of pounds. But before the sea front had a revamp, calculations of the size of the project, would show the town would suffer an inundation of over 120 million gallons of water, and engulf places such as Esplanade, Butlins, across the Warren and industrial areas of Minehead; but by pumping sand from the sea bed into where ever it was needed along the beach. Having new sea defences, it would be able to stop flooding except in an extreme event. The new Minehead sea defences has now reduced and controlled flooding dramatically! (See picture 3) Picture 4 Changes on the sea front [image]The sea front at Minehead has changed massively over the centuries. There have been many different attempts at trying to save Minehead, for example: - v Several hundreds of years ago ? the town was protected by natural shingle and cobble ridges. (See picture 4) v Before 1910 ? a sea wall was built to protect the town from flooding. v The beginning of the 20th century ?rip-rap? groynes were put in place on the west of the harbour. v Within the 20th century ? the old sea wall and sea defences were surfing frequent damages and had to be rebuilt a number of times. v In 1997-1998 Minehead? current sea wall and defences were built. Yet with the 1.8 miles of sea defences at Minehead was conceived to firstly stop regular flooding on the town and secondly, to stop coastal erosion by the waves and longshore drift. The people that were responsible for the construction and funding of the new sea wall and other defences were the Environment Agency, West Somerset Council, Butlins and Somerset County Council. They all came up with three formulated options. Option 1:- Option one involved increasing the height of the beach to the height of the promenade by importing vast amounts of sand a cobbles. This would cause the waves to break further away from the shore. This scheme was eventually considered unacceptable because it would have required too much long-term maintenance. It would have also needed the placement of groynes that were considered by the councils to be excessively long. [image] [image]Option 2: - Option two was to increase the height of the sea wall in excess of two metres to try and stop it breaching in inclement weather conditions. This scheme was eventually ruled out because of its adverse visual impact and because it would disrupt disabled access to the beach. [image] Option 3: - This option was developed as the preferred choice from the beginning. It would combine a small extension to the existing sea wall (0.6m) with replenishment of the beach height to around two metres. This not only causes waves to break further offshore but also eliminates waves topping the wall ?in all but extreme storms?. A series of four rock groynes were built to stop the movement of the newly replenished beach (by longshore drift, see diagram) to the eastern side of the bay. The material used to restore the beach would be pumped from the middle of the Bristol Channel. 180,000 tonnes of rock armour was also placed at the base of the wall to break up the energy of the larger waves. This rock armouring occurs along Quay Street. Along Warren Road, stepped concrete revetment was used to break up the larger waves and provide good access to the beach. Longshore Drift ? An Explanation Waves rarely approach any beach at right angles. When a wave breaks, the swash (foaming water rushing up the beach) carries material up the beach at the same angle at which the wave approached it. The back-swash then carries material back at right angles to the beach under the influence of gravity. This causes the zig-zag movement of material across the beach. Longshore drift usually happens in the same direction as the prevailing wind. In Minehead, the prevailing winds come from the Southwest so therefore the direction of longshore drift is Easterly. Current sea defences The current sea defences at Minehead had a shaky start from the planning and construction side, with each attempt changing. However the ?first sod? of the new scheme was cut in January of 1997. This launched the first phase of the project. The following items were to be constructed in the first phase; the sea wall, rock groynes (see picture 5) and armouring, raised areas and shelters, viewing and access ramps, and extension to the town culvert and finally the landscaping of the area. The 100,000 tonnes of rock needed for the armouring was transported from a Mendip quarry. This would have normally involved many lorry-loads of rock arriving at the site. Minehead does not have the infrastructure to support the extra strain on the roads. The Environment Agency wanted a ?greener? solution to this problem and so involved the West Somerset Railway. The company operates a steam train service, usually for tourists, between Bishops Lydeard and Minehead. The company agreed to transport the rock. The fee for using the railway benefited the area because it has gone into improving the rolling stock on the railway. Picture 5 [image]Phase two; this phrase involved the transportation of 320,000 tonnes of sand to replenish the beach. This cost for this was around £2.4 million. The sand was transported by Ham Dredging from a sand bank between the two islands of Flat Holm and Steep Holm (around 20km from Minehead). The sand was then sieved to provide acceptable standards for holidaymakers. Once the sand was in place, many bulldozers levelled it out. Some money went into improving the amenity value of the site, with new streetlamps and a sculpture to mark the end of the South West Coast Path. In May 2001 the sea defences were officially opened. Minehead?s Sea Defence Project The scheme was promoted by the Environmental Agency?s Somerset Local flood Defence Committee Funding Authorities:- Ministry of Agriculture, Fisheries and food, Environmental Agency, Somerset Local flood Defence Committee, West Somerset District Council and Butlins. Lengths The length of Sea Defence ? 1.8km! Quantity or rock armour ? 100,000 tonnes! Quantity of sand and shingle ? 320,000 tonnes! Consultants Engineering: Mouchel Consulting Ltd. Landscape and Environmental Planning Consultants: Nicholas Person Associates Ltd. Contractors: Phase 1 ? Carrillion Civil Engineering Phase 2 ? Ham Dredging Cost Cost of construction (Phase 1) ? £9.9 million! Cost of construction (Phase 2) ? £2.4 million! Total cost of construction ? £12.3 million! Comparing MineheadSeaDefences to Cyprus?s PerneraBeachsea defences On Pernera Beach in Cyprus, the same type of sea defences have been put in place, as well as the same type of groynesâ??â??â??..the ?rip-rap? ones. Before the defences were put in place in Cyprus, they found that they were also losing one of the Islands best tourist beaches. So the government helped to raise money for the new sea wall and defences to be put in place and help save the beach. Although in my opinion I don?t think that the defences are as effective as Minehead because on the one hand they have stopped beach from eroding quickly, and helping the area to become a tourist spot; but on the other hand, they haven taken up a lot of the beach, spoilt the view and it makes it harder to swim, as you have to be very careful where about you swim. Advantages and Disadvantages of the Sea Defences Advantages of the Sea Defences Disadvantages of the Sea Defences Advanced flood protection system saving the town from constant tidal flooding. The cost of the sea defences was in total around £14.5 million. The economy of the town would be greatly reduced if Butlins moved their resort from Minehead. They also have flood protection. The promenade area was ?out of action? while the new sea defences were installed. This could have affected the business of the arcades and hotels on the seafront. Longshore Drift is minimized by the new rock (rip-rap) groynes. Some residents could find that the value of their houses has depreciated because of the sea wall blocking the view of the bay. The modern and highly amenable promenade area is an attraction for tourists. It is clean and well kept. The ?Marmite? effect. Some of the residents like the modern look of the sea defences. Others think that it is an eyesore because it is not in keeping with its surroundings. The sea defences have brought Minehead into the twenty-first century with their modern looks. The better lighting and seating not only benefits tourists but also locals who want to use these facilities. The new sea defence system reduces the annual outlay that is spent on clearing up after the regular tidal floods. The West Somerset Railway?s rolling stock has been improved because of their rock haulage contract. This attracts more tourists. The newly designed access ramps have greatly improved disabled access to the beach area. The issues with Minehead sea defences are highly complex. The table of Advantages and Disadvantages above show you just some of the issues involved Rounded Rectangular Callout: The Sea defences have ruined the traditional seaside atmosphere of the town. They donâ??t keep in with their surroundings. The new sea wall has ruined my only beautiful view across the bay. I do appreciate however, having easy access onto the beach by the new steps and ramps for disabled and elderly people like myself. Rounded Rectangular Callout: I think that with the new sea defences within the area are excellent. Not only have they been made to look modern they now protect my business from flooding all year round. When I use to get flooded to use to cost me several thousand pounds every year to repair the damage. Other people?s opinions Local shopkeeper/Hotelier Elderly Resident of Minehead Rounded Rectangular Callout: The Butlins Family is immensely pleased with the work done to prevent flooding here in Minehead. Bultins contributed money into the project Rounded Rectangular Callout: Minehead terminus used to be flooded all the time, when tides breached the old sea wall. The new sea defences have halted this. When the company was approached to transport the stone for the defences, we jumped at the chance! The money from the contract has gone into improving the rolling stock for tourists. Butlins Employee Contractors Rounded Rectangular Callout: I think the new sea defences in Minehead are very satisfying. They look very attractive and modern. They also seem very clean. The seating areas are pleasing and the wall is designed to stop my four children from climbing along it. I also think that the extra lighting makes me feel safe at night when walking along the sea front. Rounded Rectangular Callout: Minhead Environmental Protection Group is exceptionally pleased with the sea defences. The new rock armour is providing a new home for much marine life such as crabs. The new sea wall was built methodically with the stone transportation done in the most environmentally friendly way most possible. Single mother of four from an impoverished region of mid-Wales Environmentalists My Opinion and Conclusion In my opinion the sea defences at Minehead are effective. My claim is backed up with other research from other sources like the Internet and Environmental Agency publications. From looking within the table I produced, you can see clearly how the advantages have outweighed the disadvantages. When you look at the local communities opinions, they appreciate the sea defences because they stop yearly flooding, and from ruining their businesses. They have also enhanced the aesthetic appeal of the area and have encouraged much wildlife into the area. The ?rip-rap? groynes that were an integral part of the sea defence system seem to be performing their duty admirably, and keeping the sparse bay in a reasonable state. I believe that the sea defences have only enhanced tourism in the area because they offer a protection to the highly profitable Butlins holiday resort in Minehead. The resort is now not flooded regularly and offers a better attraction for tourists.

Sea Defences at Minehead and Their Effectiveness 8.5 of 10 on the basis of 1848 Review.