Flood risk of a local river

Authors Avatar

Describe how both fieldwork and research can be used to investigate the flood risk of a small local river.

Fieldwork is the process of obtaining information by personally collecting primary data, such as measuring wind speed. Research involves using media such as the internet and newspapers to obtain information. The small river in which we investigated flood risk was Loughton Brook, a river which originates from a spring in Epping Forest, runs out through Staples Road overflow pond and through a highly urbanised area of Loughton, eventually joining the River Roding. It varies in width from 0.7m to 2m and in depth from around 0.7cm at the origin to 2m or higher, especially at the reservoir. The brook flooded in 1987 and 2000, but still poses a severe flood risk.

To investigate the flood risk, several different methods can be used to assess how prone the river is to flooding.

Precipitation is obviously the key factor we must consider when assessing flood risk; the more rain, the more likely it is to flood. Using simple rain gauges, emptied and measured every 24 hours, we can measure rainfall and from that, work out how much water the river will have to cope with. Large amounts of rainfall can mean that problems with the river such as small blockages or thin channels can be multiplied. However, rainfall reaching the river can be affected by other factors.

Join now!

Interception plays an important part in flood risk, as it dictates how much water will reach the soil to be carried as surface run-off or slower processes. To measure interception rates, insert large funnels into jars to collect rainwater, and place them in different vegetation areas, as well as in open air. By measuring these every 24 hours, we can see how the amount of rainfall reaching the floor varies. For example, 100% of the rain will hit the floor in uncovered areas; the deciduous areas will provide part cover, but only in spring and summer, and the coniferous ...

This is a preview of the whole essay