MAJOR house building schemes across Oxford could grind to a halt as the city’s water and sewerage network may not be able to cope, it was claimed last night.

Thames Water has said the city’s infrastructure may not be up to handling hundreds of new homes planned by Oxford City Council .

It comes as residents say serious flooding this month in Northway shows the ageing drainage system cannot even deal with current levels of housing.

Stockleys Road, Borrowmead Road and Maltfield Road were under two feet of water on August 5, flooding garages and terraces.

But residents say 1,200 homes proposed nearby at Barton West would bring much worse flooding – with the prospect of the local sewerage and drainage systems being “totally devastated.”

With the city council’s list of sites for development going before a planning inspector on September 10, Thames Water informed the council: “The capacity of water infrastructure may not be able to cope with new development and further investigations may need to be funded by the applicant.”

And it delivered a further blow to the city’s housing plans by cautioning that infrastructure work – costing millions – could take up to three years to complete.

Earlier this summer, Thames Water told the council the Barton West scheme should not go ahead without upgrading the infrastructure.

But it has followed this with a list of earmarked sites, where it says the water supply or sewerage network capacity is “unlikely to be able to support the demand anticipated from development”.

Sites include Wolvercote Paper Mill, Warneford Hospital, Ruskin College, Railway Lane in Littlemore, Northway centre, the Nielsens site near Thornhill Park and Ride , Roger Dudman Way in West Oxford, Canalside in Jericho, Blackbird Leys central area, Bertie Place off Abingdon Road and the Barton Road cricket ground site.

It says sewerage capacity is insufficient to support the ongoing Oxford Brookes University Gipsy Lane campus redevelopment, key workers’ accommodation at the John Radcliffe Hospital and facilities at the Nuffield Ortho-paedic Centre in Headington.

Thames Water spokeswoman Natalie Slater said: “Having reviewed the sites proposed in Oxford City’s Sites and Housing Plan, additional infrastructure may be necessary. Where necessary, we require developers to fund studies to determine the impact of the development on existing infrastructure, and if this work identifies additional capacity is required, the developer may again be required to fund this.”

Colin Cook, city council board member for development, said: “Thames Water is covering its back. I don’t think it will have that big effect when it comes down to it.”

But Mr Cook said the prospect of huge infrastructure costs at Barton West meant the council was unlikely to secure 50 per cent affordable homes, as it had hoped.

Georgina Gibbs, of the Northway Residents’ Group, said: “We saw really bad flooding on August 5, with water halfway up the doors of cars. There would be a devastating impact if all these new homes simply tried to tap into the existing sewerage system.”

Disabled pensioner Betty Fletcher, of Stockleys Road, said: “The water came within two inches of my home. The idea of building even more homes before they sort this out is simply ridiculous.”

l The way has been cleared for hundreds of new homes in Botley and Cumnor Hill thanks to a £7m new drainage scheme.

Almost 450 homes are set to be built and the £15m revamp of Seacourt Retail Park can also go ahead thanks to Thames Water’s £7m sewer expansion project.