Diary of events on 16th August:
- 12:15 - Dry in Boscastle with clouds visible in Camelford
- 12:30 - Heavy rainfall begins
- 12:39 - Flood-watch issued
- 15:00 - First of many power cuts, caused by lightning
- 15:30 - River Valency begins to flood
- 15:46 - 2m rise in rivers in one hour reported
- 15:53 - Fire Brigade mobilised
- 16:00 - All access roads closed
- 16:30 - A 3m wall of water floes through Boscastle at 64kph
- 17:00 - Floods reach peak level, cars swept away and buildings destroyed
- 17:10 - Major incident declared, RAF search and rescue alerted.
The natural characteristics of the area make the village vulnerable to flooding. The small catchment includes the upland area of Bodmin Moor which consists of relatively impermeable land and rock. There are steep sided valleys that converge as they run towards the sea which means water is funelled towards the village and after heavy rainfall the surface run-off quickly reaches the rivers which increases the likelihood of flash flooding.
Furthermore, the summer of 2004 had been extremely wet so by August the ground was saturated. On the 16th of August the clouds that formed where the remnants of hurricane Alex that had moved across the Atlantic Ocean, these clouds remained stationary over the North of Cornwall beacuse of converging winds. Throughout the afternoonan estimated 1,400million litres fell in just two hours. The rainfall rapidly made its way into the rivers that rose nas they flowed towardas Boscastle.
The risks of flooding has been increased in Boscastle due to the amount of building that has taken place alongside the river as well as the construction of small bridges which trap material that is being washed downstream creating a 'dam-like' effect.
The flood of 2004 was a flash flood - an…