Inquiry told upgrading of M50 will not add to noise

The addition of an extra lane of traffic to the upgraded M50 motorway would not increase the noise levels from the road, a noise and vibrations expert has told a Bord Pleanála inquiry.

A series of measures would be put in place during construction, and when the new widened road was in operation, to minimise the noise disturbance to residences and businesses along the route, Mr Christopher Dilworth, an engineer and member of the British Institute of Acoustics, said yesterday.

The M50 is being widened to three lanes along 31km of its length and 10 of the access points or "interchanges" are being upgraded along the route to reduce the average travel time by 19 per cent in 2008 and by 11 per cent in 2023.

During the construction phase noise would be created by dozers, dump trucks, asphalt-spreaders, road-rollers, concrete pumps and vibratory rollers.

However, Mr Dilworth, who has been contracted by Dún Laoghaire/Rathdown County Council, the promoters of the upgrading scheme, said that the background traffic would help to mask any noise from the work. "Many construction activities will, in fact, be inaudible at most nearby properties," he told the inquiry.

Vibrations might be perceptible in nearby housing estates, but Mr Dilworth said that this was "unlikely to be of sufficient magnitude to give rise to structural damage, cosmetic damage or even undue disturbance".

A "low-noise" road surface was being applied to the entire length of the upgraded motorway and solid barriers were being erected at 127 locations to minimise the noise from the addition of the new lane.

"The low-noise surface will reduce the levels of traffic noise by quite a relevant degree. The noise from the traffic will not increase and, in some cases, there will even be a small decrease," he said.