River flooding in an MEDC - Morpeth floods of 2008 | ||
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Background to the Morpeth Floods
Morpeth is an ancient market town situated in a loop of the river
Wansbeck in the northeast of England about 15 miles north of Newcastle
upon Tyne and 12 miles west from the North Sea. The physical form of the
town with its existing street patterns was established in mediaeval
times and its motto is “Inter Sylvas et Flumina Habitans” -
"Living amid the Woods and Waters".
Previous flooding events occurred in 1863, 1876, 1877, 1878, 1881, 1886,
1898, 1900, 1903, 1924, 1963 and 1968 (Cotting Burn). Following the 1963
flood, a flood defence scheme was established. Flood walls were erected
on the north bank to protect the main business district. Housing
properties at Middle Greens on the south bank were also protected by
flood walls. When the Wansbeck swelled on the
6th and 7th September 2008,
the floodwater simply flowed over the top of the defences, which were
not high enough to hold back the volume of water.
Rainfall
The
flood is currently estimated to have been a
1 in 115 year
event. Prolonged rainfall coincided with the flood peak
from higher areas of the catchment
which led to a
peak water level of 3.99 metres was recorded in the river channel, the
biggest flow ever recorded in the Wansbeck.
The Environment Agency recorded 150 millimetres
of precipitation falling in the Wansbeck catchment between Friday 5
September and Saturday 6 September.
Figures suggest that in Morpeth alone there was 86 millimetres
of rain compared to an average of 74 millimetres for a month.
The
huge volume of water caused the drainage system to back up, plus Oldgate
Bridge obstructed the flow.
Housing
Several houses along the banks of the Wansbeck date back to the 14th
century, but many buildings near the town's main thoroughfare, Bridge
Street, were built in the 1970s and 1980s – after the town was
devastated by the flood of 1963. The Environment Agency is strongly
opposed to building on flood plains, which puts properties at constant
risk of flooding. Building in these areas can also damage a river's
natural drainage ground and push floodwater further downstream.
Of the 1,062 properties sited on the flood plain, only 62
escaped the destruction inflicted by the rising Wansbeck at the weekend.
Physical Factors
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8.Morpeth floods by rgamesby |
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Impacts
During 6 September 2008, more than 400 residents were evacuated.
Shelter
was provided in the Town Hall, King Edward VI High School and County
Hall. An error made by the Environment Agency's warning system meant
that 198 properties in the Middle Greens area of the town did not
receive a flood warning. Fire fighters, ambulance crews, the RAF, the
RNLI and the British Red Cross were among the emergency services
involved in rescue and recovery operations over the weekend. Many
residents had to be forced from their homes, and lived in caravans or
with relatives as rebuilding took place.
More than 1,000 houses were affected when the
River Wansbeck burst its banks on Saturday, September 6, 2008.
995 properties in Morpeth town centre were directly affected by the
flood water. Early estimates suggest that damages could be over £10
million. On Sunday 7 September, Morpeth Lions Club and the Red Cross
launched the Morpeth Flood Disaster Fund and by Wednesday 10 September
had raised over £20,000. |
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Future Management - LONG TERM RESPONSES
Proposed Flood defences for Morpeth
The Environment Agency is proposing the creation of an upstream
reservoir to restrict water volumes flowing through the town in the
event of flooding.
More flood walls would also be built to prevent the Wansbeck
bursting its banks, as happened in 2008 when about 1,000 properties were
damaged.
Many parts of Morpeth are already protected from a flood which has a
one in 50 chance of happening in the town in any given year, the agency
said.
The new walls would be built in areas such as High Stanners and Mitford
Road, which are currently undefended.
In the event of flooding, the upstream reservoir - which would
hold over one million cubic metres - would only allow through a volume
of water manageable by the town centre defences.
The new flood walls would also be "less obtrusive", at up to
1.6m (5ft) tall.
The agency said the new defences would provide protection from
a flood that has a one in 115 chance of happening in any given year -
the conditions which occurred in September 2008.
These options would
be complemented by improvements to culverts in Morpeth.
Increasing the culverts’ capacity should reduce the risk of flooding
from Cotting Burn, Church Burn and Postern Burn.
Further
details of the flood defence works in Morpeth town centre;
They
are:
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Think about it
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