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Nishay PatelLynmouth Flooding Case study12/10/2008
The small coastal town of Lynmouth became known throughout the world for the disaster that struck in August 1952. It had rained steadily since mid morning and by 3pm, the sky was so overcast that the street and house lights went on. On the evening of the 15th, a storm sat over Exmoor and dropped 11 inches of rain in 24 hours. This means that a whole months worth of rain had fallen in just the first 2 weeks of August. In the days prior to the flood, it had been very wet and Cold, moist and unstable air ascended up the northward facing slopes of Exmoor. This introduced more moisture into the already heavy raining area. The West Lyn River had risen to 30ft above previous levels. A whopping 40ft of water gushed through the town destroying anything that got in its way.
This caused the East and West Lyn Rivers to rise suddenly and join together, called a confluence. Both the rivers quickly burst their banks, and water levels continued to rise as the rainwater drained from the moor. The steep valleys surrounding Lynmouth meant that the water was not only deep, but also fast moving sweeping away trees, bridges and other large items. The human factors of the flooding were that, flooding is made worse in towns and cities, as the ground is mostly concrete. If a flood occurs, then there will be nowhere for it to flow into, as concrete cannot absorb water like earth can. This causes surface runoff Another human factor of the flood is that there were not many trees, meaning that they could not absorb water, or stop rain from hitting the ground, as there was nothing there to do it. The physical factors of the flood were that, it had been a wet summer, and the peaty soil was already saturated and could absorb anymore water. Another factor is that there was too much rainfall! The torrential rain had caused the river to burst its banks horribly. The streams on Exmoor were already full to overflowing, meaning that any extra rain would cause an overflow. Bridges created 'debris dams' as trees and boulders blocked them. When they burst they released a torrential wave of water, which surged into the village. Signs such as the discolouration of the water were ignored. Locals just assumed that if it were important, someone would have spoken up already. It was clear that nobody had thought that a flood would have occurred at all because, there was very little flood defences and houses had been built right up to the river on a flood plain. The flood left 30ft walls of debris; mainly from the dozens of houses, shops and cars it had swept away. 15 ton boulders were carried down the river as if they were just twigs, also crushing many homes and cars. Thirty-four people lost their lives in the Lynmouth flood disaster and 39 buildings collapsed. Many bridges, roads and power lines were destroyed during this flooding. Survivors told how the air smelled of sulphur on the afternoon of the floods, and that the rain was so hard, it hurt people's faces.
Flood prevention strategies
The Lynmouth flood did not go unnoticed. The town has now added flood defences, and so they should be safer if a flood should occur again. The river was also widened and deepened so that there was more room for water to flow in before it reaches the sea. There is now more space between the river and the town. The town is safer, as if there is another flood, the river is slightly further away, giving the townspeople more of a warning, especially if there is a slow flood. There are mounds on the riverbanks, which means that river cannot easily burst its banks because the banks are higher. The harbour is larger as it is easier for the river to reach the sea. The Levees were also raised which gives the river more space to flow. Lastly, the river has been straightened so the water manages to reach the sea faster. This Reconstruction took several years. Plans were drawn up and a model produced, which was used for public debate.
Lynmouth is a village in Devon, England, on the north edge of Exmoor. It was made popular in Victorian times during which it became known as Little Switzerland. Lynmouth is surrounded on each side by high, steeply sloping cliffs and there are great views for miles around. The village has fascinating shops offering a range of crafts, ceramics, glassware and pottery. Many holiday makes come to enjoy the slow pace of the countryside and to get away from the hustle and bustle of the city.
The river seen here is the East Lyn River. The West Lyn River joins it at this point. This is called a confluence.
This is the rivers mouth. It is very close to Lynmouth and is where many houses and buildings were destroyed.
Not many trees in the centre of Lynmouth.
The West Lynn River was very narrow and formed an oxbow lake in the centre.
The West Lynn River is now wider, straighter and does not split into two.
The harbour is larger then before the flood occurred so that efficiency to the sea is greater.