Soft Engineering River Management
AQA GCSE Geography > Physical Landscapes in the UK > River Landscapes in the UK > Soft Engineering River Management
Soft engineering river management schemes work with the natural processes along the river to reduce the risk of flooding.
Flood warnings and preparation
UK flood alert map – click to view current alerts.
Flood warnings and preparation involve developing a system of alerting people to the risk of flooding. In the UK, the Environment Agency is responsible for warning people about flooding through TV, Radio, the internet, newspapers, and apps.
Advantages
The impact of flooding is reduced as people are better prepared. There is more time for people to move things upstairs, put sandbags and other flood defences in place and evacuate.
Disadvantages
Warnings do not stop a flood event. Not all people will be aware of flood warnings.
Floodplain zoning
Flood plain zoning
Floodplain zoning involves putting building restrictions on floodplains at risk of flooding.
Advantages
Buildings are not constructed in areas at risk of flooding. Impermeable surfaces are not constructed on the floodplain, so the risk of flooding is not increased.
Disadvantages
The growth of urban areas can be limited if building on floodplains is restricted. The risk of flooding is not reduced in floodplains that have been built on in the past.
Planting trees
Afforestation
Planting trees increases interception and lag time (the time between the peak rainfall and peak river discharge). This reduces the risk of flooding.
Advantages
Discharge in the river is reduced. The trees also reduce the risk of soil erosion, which can reduce the river channel’s capacity to carry water.
Disadvantages
Restricts what land can be used for, particularly in the upper stages of the river valley.
River restoration
River restoration
River restoration involves returning a river to its natural state. This can involve removing man-made levees or removing river straightening.
Advantages
Discharge in the river reduces, meaning there is less risk of flooding downstream. Little or no maintenance is required, which makes this a low-cost solution. Biodiversity is maintained along the river.
Disadvantages
Flood risks can increase if nothing is done along the river.
