National contractor GRAHAM has been appointed by the Environment Agency to deliver the Oxford Flood Alleviation Scheme, one of the most significant flood defence projects in England. The scheme will be built along the River Thames in Oxford and will protect all properties in the city currently vulnerable to flooding from the river. Over its lifetime, the scheme will save more than £1.8bn by reducing flood damage and disruption.
GRAHAM will create the 5km long scheme, consisting of a new stream and wetland wildlife corridor to the west of Oxford city centre, running from just north of Botley Road south to Kennington, where it will rejoin the River Thames.
The scheme will involve lowering parts of the floodplain to create the new stream and building new flood walls and embankments in some areas. When water levels in the River Thames and other existing streams are high, water will overflow from the new stream and start to fill the lowered floodplain next to it.
These measures will reduce the frequency of flooding by creating more space for water within the existing western floodplain of the city.
This work will reduce flood risk, while protecting the railway, local roads and key utilities including broadband infrastructure.
It will also bring additional environmental benefits, including creating more than 20 hectares of valuable new wetland habitat which will link up existing wildlife sites, and approximately 16 hectares of floodplain meadow.
Alastair Lewis, Contracts Director at GRAHAM, said: “This is an extremely important project, given Oxford has lived with the threat of serious flooding for generations. The vital piece of infrastructure will tackle the flood risk directly in a way that works with the landscape rather than against it.
“Our experienced team is well-versed on handling the complexities that come with this kind of work, and are very excited to be working for the Environment Agency on such a prestigious project. We look forward to delivering something that will make a real positive and lasting impact to the city.”
Robbie Williams, Environment Agency Project Director, said: “The Oxford Flood Alleviation Scheme will provide the communities of Oxford with peace of mind from the threat of flooding, for decades to come and will leave a lasting green legacy.
We are really looking forward to working with GRAHAM, following a rigorous tender process.”
The newly created channel will carry excess flow from the nearby Seacourt, Bulstake and Hinksey Streams during floods, reducing water levels in the main river and cutting the frequency of flooding in built-up areas.
The works also include new flood embankments and walls, culverts, bridges and flood gates. Removal of Towles Mill weir, a historic river barrier on the Seacourt Stream, will allow fish to move freely through Oxford’s waterways for the first time in more than a century.
The scheme has the support of a broad partnership including the Environment Agency, Oxfordshire County Council, Oxford City Council, the University of Oxford, Thames Water and National Highways.
Construction is expected to begin in 2027 and will take up to 5 years to complete.