river severn Flashcards
when did it occur
mid-late june 2007
Areas on the Severn
Shrewsbury, Worcester, Gloucester, Tewkesbury, and Upton.
average discharge cumecs and catchment size (Upper)
52 cumecs and 580km squared
average discharge cumecs and catchment size (middle)
60 cumecs and 3700km squared
average discharge cumecs and catchment size (Lower)
100 cumecs and 9895 km squared
Physical Causes
Heaviest rainfall in 50 years – 150mm of rain in 2 days
Previous rainfall meant soil was already saturated and river was already flowing at maximum capacity.
Human Causes
3 miles of the new Worcester ring-road (A4440) and other large roads and motor ways increases impermeable surface area.
Further tarmacking and extended hard shoulders have done the same as ‘smart motorways’ are being developed.
Worcester city has been allocated 29,000 new homes by 2040, many of which will be built near/on River Severn flood plains.
Also increased density, from 28 dwellings per acre in 1950, to 40 dwellings per acre in 2010.
Impacts
Upton was totally cut off – 2,000 residents for 2-3 days.
Over 163,000 households were affected by the flood, with more than 165,000 insurance claims being made.
13 people died during the floods.
damages cost
Bill for damages likely to be over £33 billion.
Further impacts at tewkesbury
Mythe water treatment near Tewksbury was flooded and shut down, leaving 350,000 people across Gloucestershire without drinking water.
In Tewkesbury, at the end of November there were still 1,800 people out of their homes, with 200 families expected to be living in caravans over the Christmas period and into early 2008.
Responses
34 new flood defences built by 2008, protecting over 30,000 homes.
Upton flood barriers - £44 million – Protects 64 houses with a 1 in 150 chance of flooding each year.
also raising the A4104 by 0.8m.
Local dredging of streams and smaller tributaries.
Severn Trent water spent £36 million on new pipelines and flood defences around their treatments.
