In August 2004, the village of Boscastle in Cornwall experienced a devastating flash flood due to an intense downpour that lasted for several hours. This unfortunate event highlighted the importance of implementing effective flood management strategies.
Let’s look into the specific measures that were taken to prevent similar disasters in the future:
Hard engineering strategies involve constructing physical structures to help control and manage the flow of rivers.
The river channel in Boscastle was both widened and deepened to increase its capacity. This change allows the river to hold a larger volume of water during heavy rainfall, therefore decreasing the risk of overflow and potential flooding.
The existing low bridges were replaced with wider ones. Low bridges often act as barriers, causing an accumulation of vegetation and debris, which obstructs water flow and increases flood risks.
The newer, wider bridges facilitate smoother water flow, reducing the likelihood of blockages and the resulting flooding.
To counter the threat of floods carrying away vehicles, the car park level was raised. In this case, permeable materials were used for the surface to allow water to infiltrate the ground.
This decreases surface runoff and prevents water accumulation, which helps to protect property and human lives by minimising the impact of floodwaters.
Soft engineering strategies aim to work with natural processes to manage flood risk.
In Boscastle, tree management was important in reducing blockages and channel obstructions during floods.
Dead trees, which could potentially be swept away causing obstructions, especially under bridges, were removed. Also, landowners were encouraged to maintain existing vegetation and plant new trees. This not only stabilises the soil but also helps absorb excess water.