The Cogges Link Road must receive Environment Agency approval before construction can get under way.

Consultants from the agency could scupper the project if they decide it would have a negative impact.

County councillor David Robertson, of Witney, said: "The Environment Agency, who were heavily involved in the recent floods, lay down the rules and if they are against the road because of the risks involved, it would be a major factor."

Mr Robertson, the deputy leader of Oxfordshire County Council, is in charge of transport strategy.

He was responding to an online poll in the Oxford Mail's sister paper, the Witney Gazette , which shows people are almost equally divided over whether the road should go ahead or whether a four-way junction should be built instead at Shores Green on the Witney bypass.

The poll was conducted following the July floods, which swamped Bridge Street, cutting the town's transport network in half.

Floods affected many areas, including the Cogges estate, where houses in Manor Road were inundated.

The Environment Agency's risk assessment might not be ready until next year.

If there are no objections the road could be built by 2011.

The Shores Green scheme would require converting the existing two-way junction on the A40 into a four-way one, with a new roundabout on the southern side of the bypass.

Mr Robertson added: "We have to make sure that by building the road we are not going to make things worse. We have to follow the new government guidelines (predating the July floods) which are now ensuring that authorities allow for a great volume of floodwaters," said Mr Robertson.

"It is an issue because everyone is sensitive about the effects of flooding since July. The risks will form part of the assessment.

The latest timetable for the link road, provided there are no serious environmental objections, is for it to be built by 2011.

If the floodplain issue does cast serious doubt on the road, then Shore Green could come back into the equation, added Mr Robertson.

"But," he said, "the personal feedback I have been getting is that the Cogges Link is still preferred by local people. Ourt own studies showed that Shores Green was not as beneficial for traffic.