The Boscastle floods were an example of flash flooding - an immediate response by a river to a period of intensive heavy rainfall. They occured on August 16th 2004 as a result of heavy rainfall that began at 12.30pm and dropped over 1.400 litres of water in just 2 hours. You can see the imapct the flooding had by looking at the images here and comparing the before and after shots of the bridge in the village centre. The catchment of the river Valency is small, (about 23 squared km) and includes the impermeable highland area of Bodmin moor. Steep sided valleys converge as they run down into Boscastle, creating a funnel effect, directing all the runoff into the main village. The ground was already saturated as a result of a very wet Auguast so the water flowed straight into the river Valency and made the water levels rise over 3m in less than 1 1/2 hours. This rise in water levels created a tide of water which flowed down through the village of Boscastle at speeds of up to 64km hour. Cars were swpt away, buildings destroyed and several peopel had to be rescued by the RAF.
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