Boscastle is a village on the North Cornish Coast which receives many tourists annually. The river Valency flows through the village and joins with the river Jordan, a tributary of the Valency, in the centre of the village. The flood of Boscastle occurred on Monday 16th of August and was one of the worst incidents of flooding in local memory. It was a flash flood event which took many by surprised due to the fact that Boscastle is not prone to regular annual flooding unlike other locations affected by such extreme events.
Causes of the Flood
The flood was a result of many exceptional factors, including both physical and human.
One major factor is the topography of the land. Boscastle is within the Valency valley. The river follows a very steep course into the valley itself from surrounding hills. Boscastle stands on the confluence of the River Jordan and the River Valency so there was an exceptional amount of water passing through the village. The steepness of the valley’s structure is a major physical factor as the rainwater falling on the hills travelled extremely quickly into the valley because of it. The shape of the valley also meant the rainwater was concentrated into a narrow space from the surrounding areas. Due to this there was an increase in run-off speed and discharge. This lead to the river channel in the village itself not being able to hold enough water and ascending from this, the flood later occurred.
On the days leading up to the flood itself, The North of Cornwall received a greatly higher than average amount of rainfall for August. Boscastle received 25% more than expected which consequently lead to saturated soils all around. Because of this, water was no longer able to infiltrate into the ground and therefore travelled as run-off over the land, meaning it reached the river a lot faster. Not only was the soil saturated but the majority of the grounds in the area was impermeable such as shale, slate and clay