As part of National Pothole Day (15th January) the Road Surface Treatments Association (RSTA) has published an updated compendium of facts and figures behind the UK’s deteriorating local road network together with a range of recommendations to address the issue. The statistics cover the last 12 months and are pulled from a wide range of government and industry sources.

Mike Harper, RSTA chief executive said: “‘Potholes: the vital statistics’ provides the facts and figures that clearly demonstrate the need to invest in a well-maintained local road network.”

Key statistics include the £9.79bn that the Asphalt Industry Alliance’s Annual Local Authority Road Maintenance Survey reports would cost to bring the local road network up to an acceptable standard and the fact that, according to the Federation of Small Businesses, if you combined the depth of all of the potholes in England it would reach 28km – that is 25 times the depth of the Grand Canyon. Pot holes are also potentially dangerous with reporting that one-in-three drivers have had an accident because of a pothole.

RSTA is calling for a number of actions to address the issue of deteriorating local roads. Harper said: “Proper maintenance of the local road network needs long-term, consistent investment if programmes of cost-effective, preventative maintenance rather than expensive short-term patch-up are to be implemented. Intervening at the right time of year, with the right surface treatment, in the right place, would extend the life of existing roads and make road maintenance budgets go much further.”

Specific actions that should be considered include injecting £1.5 billion a year to address the local road maintenance backlog by investing just 2p a litre from the existing fuel duty, providing assured funding settlement that enables planned five-year maintenance programmes and further collaboration between local highway authorities and the supply chain to forward the exchange of best practice and realise potential joint cost efficiencies

‘Potholes: The Vital Statistics’ is available as a free download from:


According to media reports the Prime Minister, Boris Johnson, is hitting the ground running. The Road Surface Treatments Association (RSTA) advises him to ensure that he avoids the potholes.

The Conservatives manifesto pledged an additional £2 billion over the next four years to repair the road network as part of a National Infrastructure Strategy calling it the ‘biggest ever pot-hole filling programme’. This has been warmly welcomed by the RSTA as a recognition that increased funding for the the local road network is essential if the decades of under-investment is to be addressed. The overall condition of local road network has deteriorated to such an extent that the latest ALARM Survey from the Asphalt Industry Alliance reports that one-in-five roads are in such a poor condition that they will need replacing within five years.

“Improving the local road network would be an immediate and real sign that the Government is investing in local communities and local economies”, said Mike Harper, RSTA Chief Executive. “The additional funding over the next 4 years would give highway authorities increased means to not only repair our roads but to develop and implement proactive programmes of maintenance that would stop the potholes from forming in the first place.”


The Road Surface Treatments Association (RSTA) was welcomed the positioning of the poor state of the local road network as a key election issue for the two major political parties.

As a result of decades of under-investment the overall condition of local road network has deteriorated to such an extent that the latest ALARM Survey from the Asphalt Industry Alliance reports that one-in-five roads are in such a poor condition that they will need replacing within five years. The survey calculates that it would take ten years and cost £9.8 billion to bring the road network up to scratch.

The Conservatives manifesto has pledged an additional £2 billion over the next four years to repair the road network as part of a National Infrastructure Strategy calling it the ‘biggest ever pot-hole filling programme’. Labour has said it would invest to make ‘neglected local roads safer for drivers’. The other political parties have concentrated on bus and rail services.

“RSTA has long campaigned for the socio-economic importance of a well-maintained road network to be recognised and the necessary levels of funding investment to be provided,” said Mike Harper, RSTA Chief Executive. “We warmly welcomed the inclusion of pledges to improve the road network in the Conservative and Labour manifestos. We hope that these promises are carried through. £2 billion over 4 years – if additional funding – is a substantial and useful amount to invest to make a real change.

However, that change will not come from just ‘filling potholes’ but from implementing proactive maintenance programmes that call upon the vast array of proven road surface treatments that would keep roads in a safe and serviceable condition and avoid potholes from forming in the first place.”


The introduction of autonomous vehicles (AVs) could result in a better maintained local road network believes the Road Surface Treatments Association (RSTA).

Current live trials are pushing the momentum for the future introduction of driverless cars. In South London, driverless taxis car are currently being tested by FiveAL. The trials will test self-driving software on real busy roads in Croydon and Bromley. Trained drivers will be present in case something goes wrong. Also in London, focused on zones 1,2 and 3, Wayve are trialling eight driverless Jaguar I-Pace SUVs. Meanwhile, by the end of this year HumanDrive will have completed a 230 mile journey across the UK to test an AV in real road driving conditions from country roads to motorways.

The future benefits of self-driving cars include less accidents, improved use of road space, reduced congestion and pollution and more efficient fuel consumption. AVs would be equipped to ‘read the road’ and replicate the instinctive human ability to simultaneously observe, analyse, decide and react to every potential different road scenario such as potholes and reduced skid resistance.

“There is a flaw in the plan. The deterioration of the local road network due to decades on under-investment means that that rather than a vision of fast, smooth, well-spaced self-driving cars, the reality could be that poor road surfaces will cause the vehicles to switch to slow safety mode and signal constant warnings of approaching poor road surface conditions”, said Mike Harper, RSTA chief executive.

However, Harper believes that the AVs having to go into repetitive safe mode could have a silver lining for local road investment. “Having to go into safe move would highlight the poor condition of the road surface and the need to do something about it. This would help local authorities with their business case for more funding to invest in local roads.”

Sensors fitted to AVs could provide live data on the road condition and so help local authorities not only know where pothole repairs are need but could provide the information necessary for planned programmes of maintenance.

Harper points to a research project being undertaken by Transport Scotland, Transport for West Midlands and Jaguar Land Rover to develop a system that enables AVs to spot and report potholes. Using a platform created by transport analytics firm Inrix, the AV Road Rules system would have a link to local road authorities alerting them to road damage or potholes to enable fast and efficient repair.

He said: “This is where AV’s could have a very useful role in improving the condition of our roads. Their adoption would provide real-time data that could prove valuable in developing and implementing surface dressing and maintenance programmes using a range of surface treatments, at the earliest signs of decay that would prevent potholes from forming in the first place.

AVs are being trialled as the future. This future should be one where potholes are prevented from forming as part of a well-managed, long term approach to road maintenance using the range of innovative, cost-effective surface treatments already available through RSTA members.”

RSTA welcomes Department for Transport’s local road funding commitment

The Road Surface Treatments Association (RSTA) has welcomed the commitment by the Department for Transport (DfT) to make the case to HM Treasury for a long-term funding settlement that addresses the backlog of pothole repairs.

The DfT’s pledge is contained in the Government’s response to the Transport Committee’s report ‘Local road funding and maintenance: filling the gap’ to which the RSTA provided evidence of the results of decades of under-investment in local road maintenance and of the need for an assured long-term funding settlement that enables councils to plan and implement effective programmes of repair and maintenance.

Funding for local highway authorities is via a combination of capital funding from the DfT highways maintenance block plus revenue funding from the Ministry of Housing, Communities and Local Government. DfT is to work with government department to develop and submit a business case for a front-loaded long-term funding for local highway maintenance to be included in the future Spending Review.

“We have been calling for such a measure for several years and so this commitment by the DfT is warmly welcomed,” said Mike Harper RSTA chief executive. “The certainty of front-loaded, long-term funding would allow highway engineers and asset managers to make better, longer term decisions, which will lead to a more resilient network, fewer potholes and a lower whole life cost for roads. It would result in more forward planning ensuring that cost effective surface treatments can be planned into a preventative maintenance programmes that prevent potholes from forming in the first place.”

He continued: “We are delighted that our recommendations have been heard by DfT and central government and we look forward to continuing to work with DfT to promote the innovative and collaborative thinking that will make maintenance funding go much further.”


The skid resistance levels of over quarter of the local road network is reported to be questionable and needs further investigation according to the latest figures from the Department for Transport. In London this rises to over half of all local roads.

According to the latest Department for Transport Road Conditions in England statistics, over the 3 years period 2016 to 2019, 28% of the local road network has questionable skid resistance levels. This is an increase of 2% over the period 2013 to 2016. The London Boroughs had the highest proportion of the road network requiring further investigation, at 53%. This has increased from 45% from the period 2013 -2016. The skidding resistance figures do not necessarily reflect actual safety levels on the roads but do indicate sites where further investigation is required.

“The increase in the number of roads requiring skid resistance is worrying,” said Mike Harper, chief executive of the Road Surface Treatments Association (RSTA). “Reduced skidding resistance can mean increase the chance of accidents especially at approaches to road junctions and traffic lights, pedestrian crossings and roundabouts as well as road stretches that have high accidents levels. Local authorities need to ensure that these potential accident black spots are made as safe as possible by ensuring that they are investigated, properly surfaced and maintained”.

The Road Surface Treatments Association (RSTA) is calling for greater use of high friction surfacing (HFS) and other surface treatments to improve skid resistance. Furthermore, the Association warns that deterioration in skid resistance could be an early indicator that the road as a whole needs intervention.

There are a number of cost-effective road surface techniques that can be used including surface dressing, retexturing or high friction surfacing.  Surface dressing not only restores skid resistance but also protects the road surface against water ingress and pothole formation. Retexturing can improve skid resistance with minimal disruption to the road user as it can be carried out at high speed at any time of year.

Harper pointed out that: “Highway budgets have been under immense pressure over the last few years. However, in most cases skid resistance can be restored without major resurfacing works. For roads in good condition, retexturing can restore both the macro and micro texture. Surface dressing can restore skid resistance and protect the road surface against water ingress and pothole formation. High friction surfacing significantly increases skid resistance and reduces braking distance and is particularly suited at high risk road sites. With skid accident reduction rates of over 50% the success of high friction surfacing speaks for itself.”

He continued: “Over the last few years there has been a decline in the amount of high friction surfacing being installed on our road networks. At the same time we have seen the numbers of fatal worryingly to start to rise slightly in recent years – up to 1784 in 2018, compared to 1754 in 2012* We must make sure that we don’t forget the lessons that led to the UK having some of the world’s safest roads, and re-double our efforts to reduce accidents year-on-year by using proven road surface technology.”

*Department for Transport; Reported road casualties in Great Britain: 2018 annual report; 2019


Predictions that Britain is facing a new ‘Beast from the East’ could prove to be bad news for those highway authorities who have not carried out the necessary maintenance of the road network warns the Road Surface Treatments Association (RSTA).

Researchers at University College London have made one of the longest-range UK weather forecasts and predicted that January – February 2020 could be one of the coldest winters for 30 years with an average temperature of 3.9C, which is 0.5C below the 1981-2010 average for the same period.

“A severe winter would have a detrimental impact upon our roads and result in a significant increase in the number of potholes, particularly where roads have not been properly maintained or re-surfaced,” said Mike Harper, RSTA chief executive.

Potholes are caused by water or snow freezing in cracks in the road surface. The expansion of ice results in damage and breaking up of the road surface which is made worse by repeated freeze-thaw cycles. Budget constraints over the last 10 years, mean that many highway authorities have not had assured levels of funding for planned, comprehensive maintenance and are forced to adopt an expensive patch-and-mend approach.

“Years of under-investment by successive governments has resulted in a decline in proactive maintenance techniques such as surface treatments, where roads are treated before they get to a critical condition, by sealing the surface against water ingress and thus preventing potholes forming.  This is what highway authorities should be doing to comply with the new code of practice, Well-Managed Highway Infrastructure. The industry constantly counts how many potholes have been repaired, but in reality we should be stopping them forming in the first place. The resultant patch-and-mend mentality of repairing potholes reactively is a very expensive solution explained Harper. “Whilst the government has provided some much welcomed additional ad-hoc funding there are over 40,000 local roads that are in such a poor structural condition that they will need to be replaced within 5 years.”

Harper called for a new approach from both national and local government: “What is needed from national government is a 5 year settlement for the UK’s Local Road Network, similar to that already in place, and delivering benefits, for the Strategic Road Network.  Such a new approach would provide that assured funding that allows local highway authorities to plan and implement the programmes of maintenance that would enable roads to withstand the impact of severe winters and ever increasing traffic volumes.


Although disappointed that there was no mention of increased funding to address the deteriorating local road network, the Road Surface Treatments Association (RSTA) has welcomed today’s Spending Review that delivered a funding package of more than £3.5 billion for local authority services next year.

“This is the biggest year-on-year increase in real terms for local authority spending in ten years. We hope that it means councils will not have to raid highway maintenance budgets so much in the future in order to fund social care and other services”, said Mike Harper, RSTA chief executive. “Councils are being forced to ‘rob Peter to pay Paul’ and as road maintenance budgets are not ring fenced this has made them an easy target.”

Cuts in highway maintenance budgets has resulted in a deteriorating local road network riddled with potholes. According to the latest AIA ALARM Surve, the bill to restore the road network to an appropriate standard is £9.79 billion.

To address this, the RSTA is calling for the investment of 2p per litre taken from the existing fuel taxation, rather than make a fuel tax cut as the Prime Minister has recently proposed.  This could provide an additional £1.5 billion per annum for road maintenance, in addition to the current spend on maintaining local roads, which is currently around £1 billion. This extra funding could make a significant difference and start working through the backlog. Furthermore, RSTA believes that there should be a 5 year funding settlement for local roads, as is the case for the strategic road network. This would enable highway managers to implement long-term programmes of road surfacing and maintenance based on assured funding decisions.

“The Chancellor has recognised the need for increase in social care spending. He now needs to consider a long-term funding mechanism to rebuild the local road network after many years of depleted highway budgets,” said Harper.