MOTORISTS have been spared six weeks of traffic misery, after contractors finished the latest stage of Selby district's water mains upgrade early.

As reported in The Press in January, Yorkshire Water began the second phase of its revamp of the water mains ring around Selby and surrounding villages - which includes relining the existing pipes beneath the A1041 Bawtry Road, between Brayton roundabout and Camblesforth.

Ian Johnson, the Yorkshire Water project manager, said: "This is an impressive achievement.

"Local motorists will be pleased the roadworks have disappeared six weeks earlier than we had anticipated - but we hope they'll say a mental thank you to Balfour Beatty for their ingenuity."

He said the contractors had been able to finish the work ahead of schedule because of a breakthrough in the way old pipes are cleaned.

He said pipes were cleaned using either a "mole" device, or a blast of 300mph air called a Whirlwind.

In the process, tiny bits of flint are put into the airflow, effectively sandblasting the pipe clean.

Mr Johnson said the innovation had been in the subsequent relining of the pipes, using a protective polymer.

"A relining rig is sent down, which travels down the pipe, rotating as it goes, spraying the polymeric lining," he said.

"Normally we work on sections of no more than 200 metres, and often much smaller than that.

"But Balfour Beatty, after research and development work, have managed to extend the rig to work on longer sections.

"This is the first time they've used it, and as far as we know, it's a national first."

The Selby ring main crew claimed the first when they successfully relined 204 metres of a 600-millimetre main in one go.

Mr Johnson said the process took only one hour and 42 minutes - the equivalent of about two metres of pipe being coated a minute.

Mr Johnson said most of the rest of the project involved excavation work on private land, which should not involve further disruption on the roads.

"From the public's point of view, the worst should already be over," he said.

"Once the project is complete in 2009, a total of 51 miles of water main around Selby will have been replaced, relined or cleaned, ensuring the area continues to benefit from a safe, reliable supply of drinking water in years to come.

"There will have been people who have had to put up with some inconvenience since we started work on the A1041 in January and we'd like to apologise.

"However, we hope customers will agree the long-term benefits are worth the short-term disruption."