AN underpass critical to the success of the A64 Copmanthorpe roadworks may be too narrow for safety, bus chiefs fear.

Concerned bus company managers - who have visited the site with a tape measure - say that if the road is not wide enough, they might have to keep their buses off the road.

But engineers behind the £4.1m road improvement scheme insisted today that the road is wide enough to allow two buses to pass safely.

Contractors have spent the last nine months replacing the Copmanthorpe traffic lights and closing a gap in the A64 central reservation, a notorious accident blackspot.

An underpass enabling traffic from Top Lane, Copmanthorpe, to cross the dual carriageway safely is being built and is due for completion next month.

However, both the First and the Yorkshire Coastliner bus companies are alarmed that their drivers may not be able to pass each other in safety on the road, which is six metres wide.

They say buses are almost three metres wide, including the wing mirrors, and space is also needed between buses and other vehicles and the kerb to pass safely.

A spokesman for Yorkshire Coastliner said: "We are very concerned and we are doing our own research. It is a problem we need to have resolved."

Paul Bell, operations manager at First York, said: "The only way to find out is to take two vehicles and try them out.

"This could have been an opportunity to build a really safe new road that would last. If it is not wide enough, we will have to carry on using the A64, which is not ideal."

Both the Highways Agency, which is in charge of the road construction, and City of York Council, which will take on responsibility for the road when it opens, say the new road is in fact wider than many existing bus routes.

Peter Evely, head of highways regulation at City of York Council, said it was adequate, particularly as there was also a cycle and pedestrian path, plus a metre of hardstanding, alongside the carriageway.

The route would also not be as heavily used as roads such as Coppergate, which was 5.8m wide.

Mr Evely said: "We have no concerns about the width of the road, it is the same width as Top Lane, and wider than the road that goes from the A64 into Copmanthorpe on the other side, which buses have been using for decades."

A spokesman for the Highways Agency said the road had been made narrower than the normal carriageway width to link in with the existing Top Lane, which was also six metres wide.

"It is only intended as a local access, and not designed to be used by large volumes of traffic. Yorkshire Coastliner was consulted as part of the consultation process on the design of the road, as was York City Council. A public inquiry was also held with a public exhibition setting out the details."

Updated: 12:13 Tuesday, August 20, 2002