2. Boscastle (2004): Case Study of flooding in an MEDC

3. Where is Boscastle?
A small town on the north coast of Cornwall. 30 kms north west of Plymouth.

4. The Land (Topography) Very small drainage basin (only 23km2).
The Valency valley is steep sided and narrow.
Confluence of two rivers (Valency and Jordan, a third stream, The Paradise, also flows through the village).
Impermeable slatey rocks with clay soils.

5. The Weather

6. The Weather Stormy weather earlier in the week.
A LOW PRESSURE (or DEPRESSION) system dominated the East Atlantic that day.
The prevailing SW winds blew the moist air inland.
Small storms with intense rain.
Stormy weather earlier in the week meant that the ground was already saturated.
A LOW PRESSURE (or DEPRESSION) system dominated the East Atlantic that day – it sucked in MOIST tropical air (including the remnants of HURRICANE ALEX).
The prevailing SW winds blew the moist air inland, this combined with a very warm morning and high temperatures to produce CLOUDS over the North Cornwall coast. The combination of high temperatures, lots of unabsorbed surface water, moist winds and the local relief (steep) meant that warm, moist air rose quickly – this led to localised storms.
These grew into small storms with intense rain – up to 200mm fell in 24 hours. At its peak 25mm fell in 15 minutes (the equivalent of 21 petrol tankers flowing through Boscastle every second!).

8. The People No flood control system. Old sewer and drainage systems.
Structures, particularly the bridge in the middle of the village obstructed floodwater.
No flood control system.
Old sewer and drainage systems with small capacities. The floods broke the system meaning that there was no controlled drainage of floodwater, it simply travelled overland causing more damage.

9. There was severe flooding in Boscastle during August 2004
There was severe flooding in Boscastle during August The most severely affected area was within grid square Summarise the map evidence which might explain the rapid and severe impact of flooding within this area. [8 marks]

11. There was severe flooding in Boscastle during August 2004
There was severe flooding in Boscastle during August The most severely affected area was within grid square Summarise the map evidence which might explain the rapid and severe impact of flooding within this area. [8 marks]

12. Label Figures 3a and 3b to show the impact of the flood on the river channel and the settlement of Boscastle. [8 marks]
Compulsory evacuation Monday 16th August
Approximately 1,000 residents and visitors were affected.
7 helicopters airlifted 100 people to safety.
58 properties flooded and 4 were demolished.
84 wrecked cars were recovered from Boscastle’s harbour, 32 more could still be out at sea.
Up to £2 million in damage.
There was also serious damage to Boscastle’s infrastructure, with water, power and telephone services cut and roads extensively damaged
Raw sewage contaminated floodwater at Boscastle and led to public health concerns after about 300m of sewer pipes were blocked or washed away.

13. Responses
The Environment Agency have improved the culvert under the Wellington Hotel in the village.
Bridge changes.
This will carry away flood water much quicker, reducing the likelihood of this happening again.

14. Environment Agency (http://www.environment-agency.gov.uk/news/1840431)

15. “Weigh up the importance of something”
Figures 5a and 5b describe the causes of flooding in Boscastle and Bangladesh in Assess the relative importance of human activities in the causes of flooding in these two locations. [8 marks]
“Weigh up the importance of something”

16. Figures 6a and 6b describe the responses to flooding in Boscastle and Bangladesh from a number of different sources. Comment on the opinion that the responses to flooding are similar in both Boscastle and Bangladesh; only the scale and effectiveness are different. [9 marks]
Are the responses the same?
Is the scale (size) of the response similar?
How effective were the responses?