2.2 - Rivers Case Study - Rivers Valency and Jordan (Boscastle), UK

Question 1

Explain the causes of flooding in Boscastle: (3)

Answer 1

• There was 89mm of rain per hour which is the same amount of water that falls in the whole of august. Due to the high amount of rainfall, nor the river or the soil could intake any more water. This caused surface run-off and the water overflowed. Even the roads could not absorb some water because they are not permeable This led to Boscastle being flooded
  • Few days preceding, Boscastle received rain hat left the ground already saturated and boscastle received 25% more rain than expected. This caused a lot of surface run-off due to the ground already being saturated and there were a lack of trees in the area that could have been used for interception. This caused the water to overflow and therefore it flooded the village of Boscastle. ]
  • Due to boscastle being located on a confluence, the two intersecting rivers Valency and Jordan both suffered from an overflow of water which caused 2 billion litres water to rush down onto boscastle. This is because of the steep gradients of the valley sides in which the 2 rivers were located in. This caused water to rush down more quickly and the ground will infiltrate less quickly causing more water to rush down on Boscastle. This led to a significant increase in flooding.

Question 2

Explain the effects of flooding on Boscastle: (3)

Answer 2

• Due to the intensity of the floods. This destroyed 58 properties and over 1000 people lost their homes. This caused many people to be homeless as a result for flooding. The government offered the affected people temporary accommodation due to them being homeless as their houses were washed away due to the floods. This led to a lot of people being displaced as a result of flooding
  • The flooding also resulted in a destruction of not only houses, but infanstructure as well. Floodwater gushed into house, shops and pubs and a nearby church was filled with 6 feet of water. The damage of infanstructure led to a lot of money needed to rebuild.
  • The estimated cost of damage of the floods was 15 million pounds. This is because of the violence of the flood destroyed the majority of the infanstructure. It destroyed houses, shops, pubs etc. This leads to a large cost of damage left in the hands of the government.

Question 3

Explain the river management taking place at Boscastle to reduce the impacts of future floods: (3)

Answer 3

• 4.5 million pounds have been spent on a flood defence scheme which includes upgrading the drainage system which started in August 2006. By increasing the drainage system, it can help stabilize the flow of water if there is any or it could reduce the amount of flooding in the villages. This helps to prevent floods in the future
  • Boscastle carpark has been raised which will stop the river from bursting its banks. It will also have a more permeable surface. This can help prevent flooding because if the soil can no longer inflitrate water, the road may be able to absorb some due to it having a permeable surface. Therefore, this will lead to the amount of flooding being decreased
  • After the Boscastle floods, The Environmental Agency has been set up in Cornwall with the purpose of monitoring flood risks and they constantly revise the measures put in place in case a flood does occur. They are also responsible for implementing natural defence systems against floods. The Environmental Agency plants 20,000 trees in 2020. This reduces the risk of floods as when there are more trees, there is more interception which slows down water from flowing to Boscastle. (1)

Question 4

Explain the opportunities that Rivers Valency and Jordan present to the people of Boscastle: (3)

Answer 4

• Boscastle has its own fishing port. Fish that live in the area include cod, mackerel, and pollack. This is beneficial for Boscastle because it can provide food for its population and it can export the fish to countries like France as well and it creates job opportunities for people to go and help fish. This can lead to more income due to exporting, and people become more productive which is beneficial.
  • Boscastle also has its own harbour called Boscastle Harbour, which provides trade to and from Boscastle. This is great for boscastle because this can support businesses in the area by importing and exporting a wide range of goods. This leads to Boscastle attaining goods and resources as well as exporting resources to provide more income.
  • Nearby farms located within 3 miles of Boscastle like the Ringford Farm all depend on River Valency for the irrigation of their crops. This can be beneficial to the farms because water is needed for the plants survival and a nearby water source can help them grow their own crops which they can then use to either consume or sell which generates income

Question 5

Explain the hazards of living near Boscastle: (3)

Answer 5

• Because Boscastle is located on a confluence between Rivers Valency and Jordan, it is extremely vulnerable to flooding as both rivers have a steep gradient in which water flows down at a fast rate. In 2004, a water tumbled down here which caused Boscastle to lose 11% of its agricultural land due to the floods. (1)
• Nearby Boscastle, there are layers of rocks called the Crackington Formation. These consist of rocks like mudstones and sandstones. The river abrades these materials and transports them to Boscastle in the form of saltation. They then erode the banks of the river in the form of hydraulic action. This is a hazard because Bank erosion can put houses and infanstructure on the river banks at risk of collapsing. (1)
• In the location of Boscastle, there are very few trees or vegetation. Trees only make up around 20% of the area in Boscastle. As a result of this, when there is rain, there are not many trees to intercept the rain. This is a hazard because there is a lack of trees for the interception of rain and instead the rain falls straight to the ground and flows to the village more quickly. (1)