Rivers Flashcards
What erosional process is predominantly responsible for the formation of plunge pools?
Abrasion
Give four things that have impermeable surfaces.
Roads
Buildings
Clay soil
Granite rock
What would lead to a larger sediment load?
- Steeper slopes
- Softer rock
- Wetter climate
Give 3 threats of flooding on the environment.
- Habitats can be polluted by floodwater.
- Vegetation can be uprooted and killed by forceful floodwater.
- Deposited silt can damage agricultural land.
Give 3 threats of flooding on the environment.
- Floods can wash people away and kill them.
- Businesses and homes can be damaged, leaving people homeless or jobless.
- Floodwater can easily get contaminated with sewage, leaving water unsafe to drink.
Mass movements are more common in what type of weather?
Cold and wet weather
What is discharge?
The volume of water flowing through a river channel at any given point in time.
What is discharge measured in?
Cumecs (cubic metres per second)
Floodplain
The flat and wide valley in the lower course.
Name 2 settlements along the River Severn’s course.
Shrewsbury and Tewkesbury.
Give an example of a year when the River Severn flooded.
2007.
Explain how rainfall helped cause the River’s Severn’s flooding in 2007.
Give at least 1 statistic.
May-July was the wettest since 1766 - June & July saw double the average rainfall.
140mm fell in a few hours on 20th July.
This caused the soils to saturate and caused lots of surface run-off.
Explain how urbanisation helped cause the River’s Severn’s flooding.
Increased urbanisation in the West Midlands increased drainage and surface run-off (more impermeable surfaces).
Explain how defences helped cause the River’s Severn’s flooding.
There was a lack of adequate defences to deal with the volume of water that entered the river.
Explain how rivers helped cause the River Severn’s flooding in 2007.
At Tewkesbury, the River Severn and River Avon meet at a confluence. The large catchments of each contributed to the flooding.
Describe the impacts of the River Severn’s flood in 2007.
Give at least 1 statistic.
Tewkesbury Abbey flooded for the first time in 250 years
Nearly 50,000 homes were flooded.
It cost the British economy over £3 billion.
State the source of the River Severn, and its annual precipitation.
Plynlimon, Welsh Mountains.
Over 2500mm/year.
Name a place in the River Severn’s middle course.
Shrewsbury.
Explain why the discharge of the River Severn increases in the middle course, using an example.
More tributaries join the river (e.g. the Ash Brook) so the discharge and speed increases.
Explain how the width and discharge of the River Severn changes in the lower course.
Give a statistic and fact.
Widens and discharge increases.
It’s 70m wide at Tewkesbury.
Major tributaries add to the discharge (e.g. the River Avon joins the River Severn).
Where is the River Severn’s mouth?
The Bristol Channel at Bristol.
Identify the major UK river system which has its source in Wales, but its mouth in England.
The River Severn.
