Surrey: M25 Noise Pollution

Much has been made of the fact that one solution to the noise problem could be to resurface this section of the M25 with asphalt. It has been suggested that a layer of asphalt could simply be put over the concrete, or the whole section could be removed and replaced. However, both of those approaches would lead to further problems. Resurfacing over the concrete with a layer of asphalt would mean that the joints between the slabs would continue to show through, which would present real weaknesses in the road surface. This is particularly the case because this section of the M25 was widened in the mid-1990s, so the joints are now in the lane, not under the white lines as they were originally. Because the asphalt on those joints would be subjected to constant wear and tear from vehicles, it would degrade more quickly, resulting in more frequent closures to repeatedly resurface the road. It would also mean that one of the causes of the noise in the area—that is, the noise created by cars travelling over the joints—would not be properly resolved.

An alternative proposal is that the concrete be removed in its entirety. However, doing so on one of the busiest sections of motorway in the country would be prohibitively disruptive and expensive. Lanes would need to be shut entirely for extended periods of time to both remove the concrete and replace it with a new surface, and the difficulty of removing the concrete from under and around bridges would further increase costs. Therefore, both resurfacing over the concrete with asphalt and replacing the road surface in its entirety are costly and disruptive options: covering with asphalt would not resolve the issue sufficiently and would lead to an increase in disruptive works on the motorway, and replacing the concrete would be prohibitively expensive and disruptive.

Having covered some of the proposed solutions to the problem of noise from the M25 in Surrey and explained why they do not make either practical or economic sense, it is important to highlight what is being done. A great deal of work is going on that aims to reduce or resolve the noise issues experienced by those who live closest to the motorway. Highways England is well aware of the noise important areas that DEFRA has highlighted, and has done extensive work to ensure preventative methods are in place at these locations. In most cases, those preventative methods take the form of a barrier alongside the road that shields the properties nearby from much of the noise. There are no further sections of this part of the M25 in Surrey at which barriers would be of significant benefit to those living in the vicinity.

There are, of course, other areas that are not as densely populated and are without barriers, but nevertheless still need noise mitigation action to be carried out. In those areas, designated as locations where there are fewer than 10 properties, it does not make economic sense to install a barrier. Therefore, in those locations, there has been an offer to install noise insulation, which is essentially double glazing designed to reduce the amount of noise experienced in those properties. I absolutely take the point made by my hon. Friend the Member for Woking that such measures do necessarily not control the noise levels residents experience in their gardens and the wider atmosphere outside properties. I also note his point about the primary school.

Nine sites on this section of the M25 have already had noise insulation offered and installed where house- holds wanted it; on a further two sites it has yet to be completed. Highways England has also identified further sites where noise insulation would be a possible solution.

Noise insulation is not the only approach being taken. Extensive work is under way to replace the joints between the slabs of concrete. As my hon. Friend outlined, the joints are one of the main causes of noise, and replacing them is not only good for the condition of the road surface but helps to reduce noise. The joints are being made flush with the surface of the road.

Although work on this section of the M25 has been focused on mitigating noise and improving the experience of those living close by, other sections of the strategic road network also have concrete surfaces. Highways England is currently running a trial on the M1 at junction 5 near Bricket Wood in which it is looking at materials and surfacing techniques that could be used to reduce the noise of traffic travelling over concrete. The trial started in 2018 and is due to complete in 2022. So far, Highways England has identified a number of potential solutions to reducing noise. There are still more options to investigate before the trial finishes in 2022. I do not want to prejudge any of the results of the trial, but the solutions that it identifies will help form the basis of Highways England’s planning as it looks to the future. That is particularly important because any ways to reduce road surface noise effectively and cheaply mean that locations such as those in Surrey on the M25 can be treated, with the lives of those living nearby significantly improved.

Finally, I turn to what is happening now and in the immediate future on this section of the M25. Highways England is focused on maintenance to ensure that the road infrastructure on this section of the M25 remains in a suitable condition. That includes work to reduce the amount of water ingress through joints. There is a programme of retexturing that will increase safety for the travelling public as it will increase grip on the road surface, which has been smoothed down over time. Highways England will also conduct a review of the joints between junctions 8 and 10 this year, with an expectation that any works will be carried out in the 2020-21 financial year.

Once again, I thank my hon. Friend for securing the debate and for the constructive approach that Members have taken to tackling an issue that affects their constituents so much. As I said at the start of my speech, I recognise the noise concerns of those living in the vicinity of the M25. The Government are well aware of these issues—as my hon. Friend outlined, he and colleagues have been lobbying on it over a number of years—and Highways England is fully committed to doing what it can to reduce noise levels in those areas.

My hon. Friend asked me to guarantee that works will be agreed within 12 months of the trial finishing. He will appreciate that I am unable to guarantee that absolutely, but I guarantee that once the trials have taken place, Ministers will work with hon. Members to ensure that we can take forward the remedial works that are possible and economical. That will be either through mitigation such as barriers, noise insulation or regular maintenance of the road surface, or through innovation and development of new techniques and use of materials to reduce the level of noise for constituents living around the M25 and for those who drive over it.