A Case Study of the Boscastle Floods
Where?
Boscastle is in North Cornwall, in the South West of England. A small seaside town, it faces out onto the Atlantic Ocean.
What?
Flash floods hit the town on Monday 16th August 2004 in a 1 in 50 year occurrence. This caused 120mm of rain in 7 hours, twice the monthly average and causing the river to rise 8/9 feet. Understandably the river broke its banks, flooding Boscastle severely.
Causes?
The main cause was quite simply the fact that there was a lot of rain. 120mm of it in fact. Seeing as it had been raining for a few weeks before, saturating the ground, the water had nowhere to go but down the 2 steep valleys surrounding the village into the river. Or rivers – Boscastle is at the confluence of 3 rivers, the Valency and the Jordan. These understandably burst and the water was funnelled into the main road. Although this particular storm wasn’t down the global warming, we are getting more heavy storms in recent years which is very likely to be to do with global warming.
Impacts?
Because of the enormous volume of the water and the shape of the hills, the water went very fast towards the sea, as high as 3 metres, and a speed of 40mph, leaving destruction behind. These speeds can move cars, 100 actually through the village, emptying and destroying the car park, washing them into the harbour and sea, or just leaving them dumped in the village. The amazing rush of water coupled with cars acting as out of control cannon balls, caused homes and businesses to be knocked down or washed away.
One 16th century building was completely destroyed by a run away camper van. Water rushed easily into homes, destroying everything inside. With the main road turned into a river, the tarmac was destroyed, likewise bridges and signs etc. Although resembling something like a production from the Doctor Who Special Effects team, miraculously nobody was hurt or killed, probably because of the event happening in the day, unlike the Lynmouth flood in Devon 52 years to the day which took the lives of 34 people. They also have the emergency services to thank, who rescued 120 people, many of whom scrambled onto their roofs. 60 people were evacuated to a nearby village.
Longer term impacts of the floods affect both the authorities and the people. People will be put off holidaying in Boscastle, an area almost totally reliant on tourism, costing their economy and the jobs and livelihood of people. The authorities will also have to replace damaged roads etc. and think about flood defences for the future. Insurance companies predict the clean up bill will run into millions of pounds. For the inhabitants of Boscastle, not only have their businesses been destroyed. The floods have damaged houses not only through pure destruction, but through damp as well. Possessions will have to be replaced as well as the floods having a great emotional impact on people.
Reduction Methods?
Considering Boscastle is a small village, which has only been flooded severely once, not much money can be allowed to be spent on stopping future floods. However, small reduction methods could be made such as deepening the river so it can hold more water. The material dug out can be used to create embankments to further deepen it. The course of the rivers could be changed, such as straightening them to make the water reach the sea faster without so many meanders to turn round. The river could be pumped underground in large pipes, although Boscastle would lose the river, which is one of the tourist appeals of the place.
The authorities have actually spent �0.8m on widening and lowering the river Valency. They’ve also put a relief channel underground which can take water away from the river when there is a lot of rainfall. Finally, they’ve inserted a tree catcher so trees cannot create dams downstream if washed into the river.
