Boscastle Floods

Boscastle Floods

1. Background information

   • It happed between Monday 16th August 2004, the peak time of the flood was between 5-6pm
   • It occurred in Boscastle, Crackinton Haven in Cornwall, England
   • The flloods were the worst in local history
   • The peak flow was 140m/s between 5 and 6pm
   • The last time this happened was in 1996 due to hurircane Lilly

2. Causes

   • Human
     • The village of Bostcastle was allowed to develop on floodplains where rainfall was high. This means that the river was unable to naturally flood. This meant instead of permeable grass that would absorb the water there was impermeable surfaces that could not absorb the water. This caused the flooding to be much worse.
     • The rainfall hit when the population was twice as high as usual
     • There were no man made flood defences. This meant that they had no extra protection from the flooding
     • Houses were built close to the river. This meant that river was not allowed the natural space it needed to flood without causing any harm. More impermeable surfaces and the houses are put more at risk, meaning the effects of the flood will be worse.
     • The drainage system was old and damaged.
     • Boscastle car park was built close to the river so it made the river channel narrow
     • Small bridges The river had been narrowed so bridges could be built so the river couldn’t carry the amount of water it needed to.
     • Small bridges had been built that were blocked by cars and vegetation. This meant the water had to flow around the bridge.
   • Physical
     • Over 60mm of rainfall fell in 2 hours (this is a months rainfall)
     • The ground was already saturated due to above average rainfall in previous weeks. This means that the ground couldn't absorb as much rainfall, more surface runoff
     • The flooding coincided with high tide
     • The drainage basin has steep slopes and impermeable slate causing run off. This means that the water reached the river quicker and the less of the water was absorbed, meaning that there was a larger volume of water.
     • Boscastle is at the confluence of 3 rivers (where tributaries meet) so there was a large amount of water in a short time.

3. Effects

   • Human
     • Homes,businesses and cars belonging to more than 1000 people were swept away by the floods
     • 90% of Boscastle's income depended on tourism but this was lost due to the flood. Tourism is the main source of income
     • Long term stress and anxiety for people that were traumatised by the flood.
     • More than half of B&Bs were forced to close, this meant that the owners lost lots of money.
     • The museum of witchcraft lost artifacts
     • It took away a year of the villages tourism because the town was unable to open to tourists for a year
     • Approx 100 homes and businesses were destroyed, this lead to a huge financial cost because there was so much damage
   • Physical
     • Coastal pollution was caused as debris and fuel from cars flowed out to sea
     • Wildlife habitats were damaged
     • It eroded the river banks
     • It uprooted trees
     • Walls and bridges were washed away.

4. Responces

   • Short term
     • Immediate rescue mission was launched. Fire engines, lifeboats and helicopters were sent in
     • More than 100 people were airlifted to safety
   • Long term
     • Deeper drainage channel was constructed on the river Jordon
     • £8000 flood defence scheme was launched by the environmental agency
     • Prince Charles made a large donation to fund to help rebuild parts of Boscastle
     • A low bridge near the harbour is being rebuilt as a higher structure as it blocked water flow in the floodj
     • The environmental Agency constructed an underground pipe that will get rid of water from the river Jordan
     • The river Valancy was widened so it could carry more water