TWO main roads in Oxford will be closed for up to 15 months as part of the three-year construction of Oxford's flood alleviation channel, new documents have revealed.

After a campaign to raise funds was successful, a formal planning application for the scheme to protect more than 1,000 homes has been submitted.

But documents for the £121m scheme have warned the necessary shutting of Old Abingdon Road and Kennington Road, probably for more than a year, will likely have a knock-on effect for the Southern Bypass and Abingdon Road.

Traffic and transport assessments by the Environment Agency have also revealed for the first time that the main routes to be used by construction vehicles will be the A34, A420, Botley Road and West Way, and the number of vehicles required will equate to approximately 'one vehicle movement each way on the A34 every five minutes during working hours'.

In the full plans lodged with Oxfordshire County Council, the Environment Agency wrote: "As with most projects of this nature, there will be some traffic disruption during construction, from new access routes to construction sites, and from construction related traffic.

"The main access routes that will be used by construction vehicles for the scheme will be the A34 via the A420 Botley Road/ West Way where we will share access to Seacourt Park and Ride, the South Hinksey Interchange on the A34 and Old Abingdon Road and the A4144 Abingdon Road."

This 'peak traffic level' is set to last for approximately 21 months within the three-year construction period.

The document goes on to say that during construction, Old Abingdon Road and Kennington Road are set to be closed for 'up to' 15 months, 'which will disrupt traffic for those accessing the A423 Southern By-Pass and the A4144 Abingdon Road and looping around the Hinksey Hill interchange and Kennington roundabouts'.

The temporary closure of Old Abingdon Road will also hit Oxford Bus Company's 35 service, which run between the city centre, Kennington and Abingdon.

In other areas, the EA warned businesses on Botley Road and Abingdon Road, the Oxford Spires Hotel in Sandford on Thames and retail parks along the scheme route should be braced for the impact of the road closures and construction traffic.

However, scheme engineers reassured the county council: "We will manage this transport disruption and increased traffic flows through measures described in an outline construction traffic management plan, which will be finalised in consultation with the highway authorities.

"We will plan deliveries in advance, keeping the roads clean and providing temporary signage to minimise disruption and maintain access as far as possible during construction."

The agency also reminded the council that the finished scheme is designed precisely to protect local roads and the railway line from the flooding which, in the past, has forced emergency closures.

Peter Rawcliffe of Oxford Flood Alliance, which has helped the EA design the scheme, said his group was 'delighted' to see the application, aimed at reducing the flood risk to 1,500 homes, go in on schedule.

However he said the group – created in 2007 to act as a voice for those affected by flooding – would now be scrutinising the 250 pages of plans in detail before making further comment.

The final planning application for the scheme comes four years after then-Prime Minister David Cameron visited Oxford in the wake of severe flooding in 2014 and pledged £42m and his full support for the scheme.

Oxfordshire Local Enterprise Partnership promised £26m, the Thames Regional Flood and Coastal Committee £14m, and local councils stumped up £2m.

The project then hit a funding brick wall before Oxford City Council announced in March that it was contributing the final £4.35m needed, which will come out of a Government grant to bring forward a massive Oxford University development on Osney Mead.

However the struggles are far from over: the EA still needs to acquire all the land it needs to construct the three-mile flood channel between Seacourt Park and Ride on Botley Road and Sandford on Thames.

Oxford Preservation Trust, the Ferry Hinksey Charitable Trust and even supermarket chain the Midcounties Co-operative, which all own parts of the land, have indicated they may not part with their land willingly.

That will leave the EA having to use Government Compulsory Purchase Orders just to start construction.

Once the land has been secured, the EA will then have to get final government approval to start digging.

The main pillar of the scheme is to dig a three-mile flood channel around the west of Oxford, starting from next to Seacourt Park and Ride, which would join the river Thames near Kennington.

Oxford Preservation Trust is hosting a drop-in meeting to discuss the planning application at The Fishes pub in North Hinksey from 6.30pm to 8pm.

The full plans are available to view via with comments open until June 14.