On the 16th of August 2004, Boscastle, a small fishing village on the North coast of Cornwall, experienced one of the worst flash floods Britain has ever seen, 1 in 400 year flood. Two and a half miles up stream from Boscastle torrential rain started. Within the space of an hour 89 mm of rainfall was recorded, causing the capacity of the river to overflow. What didn't help matters was the steep valley in which the river Valency ran through into Boscastle, causing the rainwater to collect even quicker at the bottom of the valley. The river was too narrow and too shallow to hold the rain water causing the river banks to burst. What accelerated the rate of surface runoff was the fact that most of the ground was impermeable due to the slate found in the higher grounds. The prolonged rainfall over a period of 8 hours caused extensive damage; socially, economically and environmentally. When the storm had subsided the damage was clear to see, around a hundred cars were washed in to the local harbour, local businesses washed out and buildings damaged or completely destroyed. Fortunately not as many people were hurt, though they were distraught that their homes and lives had been destroyed. People were unable to work and get an income off the back of this and to make matters worse their insurance went up too, making it more expensive for them to live there. The tourist trade was effected immediately afterwards, people describing Boscastle as a ghost town. Trees and wildlife were uprooted and scattered across the river/sea bed. Since then Boscastle has introduced flood prevention strategies, such as channel straightening, deepening and widening, so that this chaotic event does not occur again.
Case study: Bocastle
Flooding can cause problems in both developed [developed: Refers to a country that has a lot of wealth or a population that is healthy and well educated.] and developing [developing: Refers to a country that has little wealth or a population that lacks healthcare and education.] countries.
Boscastle is a small coastal settlement in the south west of England. It flooded in August 2004, washing cars and buildings into the sea and putting peoples' lives in danger.
Causes of flooding in Boscastle:
Heavy localised rainfall – 89 mm of rain fell in an hour.
Saturated ground from previous rainfall.
Topography [topography: The shape of the land.] of the land. The landscape upstream of Boscastle, a steep-sided valley, acted as a funnel directing vast volumes of water into the village.
Narrow river channels in the village itself.
What has Boscastle done to prevent flooding in the future?
£4.5 million has been spent on a flood defence scheme.
The scheme stretches along the valley, incorporating drainage, sewerage systems and land re-grading.
Boscastle car park has been raised in height, which will stop the river from bursting its banks so easily.
New drains allow water to run into the lower section of the river quickly.
The river channel has been made deeper and wider so that it can accommodate more water.