'Roads could melt': Why gritters are out in the heatwave

Gritters have been deployed across Warwickshire to help keep road surfaces cooler Credit: Good Morning Britain, ITV

People across the Midlands may be surprised to see gritters out over the next few days.

Warwickshire County Council are one of many across the region that have gritters on standby for melting roads, as the UK experiences extreme heat.

Gritter lorries are usually deployed during the winter to clear dangerous ice and snow from roads to prevent the risk of skidding for drivers.

But with the unprecedented temperatures posing an increasing risk to road surfaces, they've now come out of hibernation.

The heatwave, which triggered the Met Office's first ever red warning for heat – meaning a "very likely" risk to life – has already led to school closures and train cancellations across the Midlands.

How do gritters prevent roads from melting?

Good Morning Britain correspondent Nick Dixon at Warwick Gritting depot earlier today

Experts say when deployed, the gritters will spread light dustings of sand or 'cracker dust' which is made up of ground down stone.

This will help soak up excess tar and reduces the risk of roads melting to help minimise disruption to commuters.

Speaking to a correspondent at Good Morning Britain, Jeff Morris, Operations Manager at Warwick Gritting depot, explains how it works:

"As the heatwave progresses, the temperatures in the road can rise above 50 degrees. The tarmac at the top can begin to soften. So we're all prepped and ready to go with our gritters and this cracker-dust.

"We put it on and it soaks up the liquid bitumen and makes it safer and better for vehicles to run on. It also reflects some of the sun's rays and stops it getting worse"

cracker dust is made up of ground down stone to help soak up excess tar on roads Credit: GMB

The UK is facing travel disruption, closed schools and health warnings as the country braces for extreme heat over the next two days.

In a statement, Warwick County Council said:

"In order to combat these temperatures and their effects on our highways, Warwickshire’s gritters are on standby to spread a light-dustings of stone dust to soak up excess tar and minimise chances of road surfaces melting by reflecting a larger amount of the sun’s rays.

"This proactive work aims to help reduce the potential damage high temperatures can inflict on our roads and keep them safe, limiting disruptions to the network.

Councillor Wallace Redford, Portfolio Holder for Transport and Planning, said:

“Our gritting fleet does a fantastic job keeping Warwickshire’s residents safe and the network running throughout the winter months.

“Many residents may be surprised to see them out at the height of summer, but their work at this time of year, preventing costly damage to the roads of Warwickshire is no less important than their cold-weather work and all contributes to ensuring our residents are supported through excellent transport infrastructure.”

The council is asking residents to report any road damage directly through the council website.

Keith Brett, chair of Road Surface Treatments Association (RSTA) speaking to ITV Central

Experts warn road temperatures could reach highs of 55 degrees, with people advised to drive if only necessary.

Keith Brett, Chair of the Wolverhampton-based Road Surface Treatments Association (RSTA) is urging drivers to be patient as gritters are out more in the coming days.

"Be careful, if you are overtaking the gritter, because these would be moving far slower than a normal gritter would in the winter."

"If you look at the road and you see the road looks discoloured, then please be aware it could be slippy as-well.

He's warning that even temperatures cool down, some parts of some roads will still be at risk of melting and will need fixing.

"Working from home, would also take some traffic off the road which could help."


Why are roads melting?

The RSTA says road surfaces are generally very resilient, however, when their temperatures exceed 50 degrees, they will begin to melt, causing damage.

Even on a sunny day around 20 degrees can be enough to generate 50 degrees on the road, as the dark asphalt road surface absorbs a lot of heat, which builds up during the day.

As temperatures rise, the bitumen in roads can soften and rise to the top. This makes road surfaces sticky and more susceptible to pressure loads from heavier vehicles, leading to ridging and rutting.

Explaining why UK roads are susceptible to melting Mr. Brett said:

"Roads are built to accommodate a vast variety of situations from very freezing cold weathers to very hot summers and that's difficult to make that all encompassing.

If you live in a cold climate, you build a road for a cold climate. If you live in a hot climate, you build a road for a hot climate.

We're trying to accommodate every situation in the UK".

He says:

"Just remember these are unusual and unique times. This will be a record. The Midlands is very urban".

"There are a lot of people, a lot of drivers so yes we will see the effect of this in the Midlands. So let's be prepared and try and mitigate it as much as we can"

"People working from home if they could, would also take some traffic off the road which could help.

He adds it is vital that people continue taking precaution even after temperatures reduce, as "although the air temperature may have dropped, it may take a couple of days for road surfaces to lose the heat that they've built up"

What roads are most at risk?

The RSTA said rural, open roads with little tree cover or shade that are in direct line of sunlight will be most at risk.

As well as this main A-roads such as the A41, A42 and others that see a lot of HGV's could also be prone to damage.

How to keep yourself and your vehicle protected:

  • Only drive when absolutely necessary and plan your journey beforehand to avoid un-necessary delays

  • Ensure you've taken plenty of water with you for you and your passengers to stay hydrated

  • Carry out crucial checks on your car before you set off on your journey to avoid breakdowns

  • Park in the shade

  • If you find you have tar stuck to your vehicle, it can be easily cleaned with soap and water, but it is best to leave it until it becomes cooler