2008 Morpeth Flood

Infobox flood
name=2008 Morpeth Flood


image location=Telford Bridge 6 September 2008.jpg
duration=6 September 2008
total da

total fatalities=0
areas affected=Morpeth, HepscottThe 2008 Morpeth Flood occurred on Saturday, 6 September 2008. It was caused by heavy sustained rainfall in the preceding 24 hours. The River Wansbeck burst its banks and inundated the town’s flood defences around 1500 BST, causing damage to 995 properties, 906 of which were residential.

Background

Previous flooding events occurred in 1863, 1876, 1877, 1878, 1881, 1886, 1898, 1900, 1903, 1924, 1963 and 1968 (Cotting Burn).

The last major flood to affect Morpeth took place on 7 March 1963. Unlike the 2008 flood, the primary cause was rapid thawing of snow and ice in the town and Wansbeck valley. The winter of 1962/3 was particularly harsh and snow had built up to over 3ft in the upper valley areas. All this snow thawed in a 48 hour period, overwhelming the River Wansbeck drainage basin system. 482 homes and 21 businesses were damaged by the ensuing surge. In the after math a relief fund was set up, raising £16,000 that was paid out to 350 claims. [Morpeth Herald 6 March 2003] An estimated £50,000 of losses was suffered by businesses and the local authority. [Morpeth Herald 6 March 2003]

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.

In 1992, a record peak water level of 3.19 metres was recorded in the river channel. [Morpeth Herald "Worst on Record" Thursday 11 September 2008] The 2008 flood level was 0.8 metres higher than this. However, there was not a flood event in 1992 as the defences successfully protected the town centre.

Causes

Meteorlogical

The Environment Agency recorded 150mm (6in) of precipitation falling in the Wansbeck catchment between Friday 5 September and Saturday 6 September. [BBC News "Flood clean-up operation begins" Monday 8 September 2008] Figures suggest that in Morpeth alone there was 86mm of rain compared to an average of 74mm for a month. [Morpeth Herald "Worst on Record" Thursday 11 September 2008] Environment Agency statistics show that it was a unique event as peak river discharge was the highest that had ever been recorded. [T Willison, Environment Agency Regional Director] The intense rain fall could have been further exasperated by a sluice gate in the river estuary which had remained closed on 6 September.

Physical

The River Wansbeck Valley is narrow and steep and as a consequence has exaggerated amounts of surface runoff. Based on three storm events, a reliable flow gauge located upstream of Morpeth at the confluence of the Wansbeck and Font showed that 56% of rain fall is converted into surface runoff. [Environment Agency, Wansbeck and Blyth Catchment Flood Management Plan] Because the soil was already saturated as a result of the wet summer, the effect of surface runoff was greatly enhanced. Furthermore, increased urbanisation since the 1960s in Morpeth meant that most water falling on the town would have drained directly to the river channel. Other tests investigating the catchment lag time (time lapse between the mid point of storm rainfall and peak river level) indicate that the Wansbeck has a LAG time of only 8 hours. [Environment Agency, Wansbeck and Blyth Catchment Flood Management Plan] This means that any water falling in the catchment area would have been rapidly converted into channel flow by surface runoff and to a lesser extent by throughflow. This is due to the steepness of the valley and the soil composition.

Effects

ocial

During 6 September 2008, more than 400 residents were evacuated. [BBC News 'Morpeth a scene of devastation' Sunday 7 September 2008] Shelter was provided in the Town Hall, King Edward VI High School and County Hall. An error made by the Environment Agency warning system meant that a further 200 people were not given guidance about leaving their homes. Firefighters, ambulance crews, the RAF and the RNLI were among the emergency services involved in rescue and recovery operations over the weekend.

Economic

995 properties in Morpeth town centre were directly affected by the flood water. Early estimates suggest that damages could be over £10 million. [Morpeth Herald "Worst on Record" Thursday 11 September 2008] On Sunday 7 September, Morpeth Lions Club launched the Morpeth Flood Disaster Fund and by Wednesday 10 September had raised over £20,000. [Morpeth Herald "Morpeth Flood Appeal tops £20,000" Wednesday 10 September 2008]

Environmental

At the peak of the flood, Morpeth High Street (Bridge Street) was under 0.6m (2ft) of water. [BBC News “Flood clean-up operation begins” Monday 8 September 2008] Not since 1963 had the main street been flooded. The library suffered severe structural damage due to the heavy debris transported by the river. Such was the extent of the damage that structural engineers were required to test its safety.

Aftermath and Solutions

On Monday 8 September 2008, John Healey, Floods Recovery Minister visited Morpeth. Official Government aid was pledged to the local authority to help with costs of the disaster through the Bellwin Scheme. Mr Healey was also in talks with insurance industry chiefs, discussing their plans for dealing with a large number of claims in affected areas as quickly and effectively as possible.

Furthermore, discussions with the Environment Agency to bring forward proposals for new flood defences took place. An Environment Agency report of December 2007 suggested improvements are needed to the town flood walls. Oldgate Bridge may need some structural changes made as it has a damming effect during flood events. An upstream reservoir to hold back flood water was also proposed. If successful, improvements could be made by 2011.

Morpeth Lions Club aims to raise £100,000 which could be paid out to those without insurance.

HRH Prince Charles of Wales and Camilla, Duchess of Cornwall made an official visit on Friday 12 September. During their visit they inspected the damage and spoke with victims of the flood.

References