FIVE new park and ride sites could be built outside of the city by 2031 at a cost of nearly £75m.

A study published by Oxfordshire County Council yesterday said the sites – all in the Green Belt – should be at Cumnor, Lodge Hill, Sandford and Oxford Airport, in addition to one already announced at Eynsham.

They would have a combined capacity of up to 5,900 spaces, on top of an extra 435 added to the existing Thornhill car park and 1,070 at Oxford Parkway rail station.

The report is looking at a number of scenarios to reduce traffic coming into the city, with one recommending the closure of the city's current sites at Pear Tree, Seacourt and Redbridge.

David Nimmo Smith, the county council's cabinet member for transport, said the new park and rides were needed because of 100,000 new homes and 85,000 new jobs forecast in the county over the next 15 years.

He added: "Oxfordshire is a growing county, meaning long term solutions are needed so the transport system meets the demand of the future.

"This is only a technical study. But this means we are able to proactively respond to future challenges."

Eynsham's new site, on land north of the village, is already funded as part of improvements planned for the A40 and will be complete by 2021.

But the study, by consultancy firm Atkins and commissioned by Oxfordshire County Council, said the new site west of Oxford Airport and an expansion at Oxford Parkway could also be finished by then.

This would be followed by the Thornhill expansion between 2021 and 2026, then construction of the new sites at the Cumnor A420 junction, the A34 Lodge Hill junction and on the A4074 just south of Sandford by 2031.

It proposed the closure of Pear Tree park and ride by 2021 and Seacourt and Redbridge by 2031. Although officials said yesterday that they would remain "flexible" about whether they should remain open.

It is understood that the funding for the scheme would likely have to come from the Government. In the two scenarios looked at, new "rapid" services would either be created to serve the sites or existing routes would be extended.

The council said it was working on more detailed plans which it would publish in the future.