Phase 1 of River Thames Scheme will increase the flow capacity of three existing weirs
But residents still concerned over shortfall in funding
Feb 26th 2015
Residents living on the floodplain of the River Thames will benefit from a £30 million fund that has been agreed in a Growth Deal struck between the government’s Local Growth Fund and the Enterprise M3 Local Enterprise Partnership. The deal includes projects to develop flood defences along the Lower Thames as part of the Environment Agency’s River Thames Flood Alleviation Scheme.
The Environment Agency published a policy paper on managing flood risk from the River Thames in November 2010. The Agency said that the length of the River Thames between Datchet in Berkshire and Teddington in south-west London contains the largest area of developed floodplain in England without flood defences, with over 15,000 homes and businesses at a high risk of flooding. Major flooding, the Agency said, would cause severe disruption to the road network, the suspension of several major drinking water abstractions supplying the south-east, and threaten up to 20 electricity sub-stations.
According to the Environment Agency’s calculations, damages from a major flood of the River Thames could exceed £850 million. The Agency also predicts that the effects of climate change will double flood damages from the current level of £850 million to around £2 billion by 2055, with the number of properties at a high risk of flooding reaching 35,000. Responding to these concerns, the government published a flood risk management strategy for the Lower Thames in 2010. Its recommendations have been incorporated into the Environment Agency’s River Thames Flood Alleviation Scheme, which has been developed in partnership with Defra (Department for the Environment, Food and Rural Affairs), Thames Water, and seven local authorities including Surrey County Council.
The River Thames Scheme consists of a new flood channel, improvements to three of the existing Thames weirs, and improved flood incident response plans. The flood channel will be 30 to 60 metres wide, 17 kilometres long, and built in three sections. Residents along the Datchet to Teddington stretch of the River Thames will also be offered property-level products (such as door barriers, non-return valves and air brick covers) to make them more resistant to floods. The Environment Agency says installation of the products will benefit up to 1,200 homes. It also says that all communities between Datchet and Teddington will benefit from the River Thames Scheme, including the communities downstream of the flood channel as modifications to the weirs will also reduce water levels between Walton Bridge and Teddington.
The Agency’s policy paper said that implementing the River Thames Scheme will be carried out in two phases, subject to funding. Phase 1 includes a number of measures including ecological surveys, hydrological studies, major incident planning, installing the property-level products, and developing a funding strategy for the scheme, the cost of which is estimated at around £300 million. Phase 1 also includes construction work to increase the flow capacity of the weirs at Sunbury, Molesey and Teddington, and obtaining the necessary planning consent. Phase 2 includes building all three sections of the flood channel and associated structures, and increasing the capacity of Desborough Cut. This Phase 2 work is expected to start in 2020 and take approximately five years to complete. However, the Agency expressed the hope that construction work could begin as early as summer 2016 on the modifications to the first Thames weir.
The £300 million River Thames Scheme was regarded as unrealistic by many local residents owing to a shortage of funding. Defra had initially pledged £165 million towards the scheme, with local authorities and other partners expected to find the rest. The ‘black hole’ in funding prompted local residents to form a pressure group and to ask government minsters for more.
Defra then pledged a further £60 million in last year’s run up to Christmas, but this still left a shortfall of 25% of the estimated costs and the new funding will not be available until 2021. The Surrey residents who were devastated by the floods of 2013-2014 must now be hoping that the latest announcement will bring about the much anticipated reduction in flood risk, including the planned capacity improvements to the three existing weirs. However, the Growth Deal, which covers Hampshire as well as Surrey, also includes projects intended to enhance town centres, reduce road congestion, and create new affordable housing, and Surrey residents in the north-west of the county have complained that the funding allocated for flood risk management is not enough when compared with the billions announced for new road schemes in the area.
Photograph: Eastern Bridge over Desborough Cut © Copyright Philip Halling and licensed for reuse under this Creative Commons Licence. The Desborough Cut was constructed between 1930 and 1935 to avoid the meander of the River Thames at Lower Halliford. The cut is named after Lord Desborough who was the chairman of the Thames Conservancy at the time of its construction.