Transport Secretary Grant Shapps admitted the UK’s transport network cannot cope with the record heat, saying the Victorian-era infrastructure was “simply not built to withstand this type of temperature”. But why are extreme temperatures wreaking such havoc on the UK’s transport network? Across the country, damage to pavements due to the heat has been reported, while Luton Airport was forced to close its runway on Monday after a fault was found in the tarmac. On Tuesday, the A14 in Cambridgeshire – a major transport artery to Britain’s biggest container port – was the latest road to succumb. Police tweeted an image of a submerged road saying: “No, the A14 is not turning into a skatepark… unfortunately the pavement doesn’t do well in this heat.” How come our roads are melting? British roads are made of asphalt, but some are made of concrete. The Road Surface Treatments Association said the surface can start to melt as it reaches 50 degrees Celsius. This can happen even when the air temperature drops as much as 20 C at the end of the day because the pavement absorbs heat during the heat of the day. Why can’t railways cope with extreme heat? Forecasters said road surface temperatures could reach 60 degrees Celsius or higher due to prolonged exposure to the sun. That was certainly the case on the rail network on Monday, with Network Rail revealing that the hottest rail line on record reached 62C (144F), in Suffolk. Network Rail says Britain’s rails are pre-stressed to help them withstand high temperatures. British tracks have a stress-free 27 degrees – the average summer temperature on UK railways. Countries with traditionally warmer climates will “set” the rails to higher temperatures. When the air temperature reaches 30 degrees, the temperature on the rail can actually be up to 20 degrees higher. When steel rails heat up, they expand, which can cause a bent rail – and increases the risk of derailment. Why can’t we make adjustments to cope? Network Rail said some countries regularly experience extreme temperatures that affect their railways and may adjust their tracks between summer and winter or have other measures to manage the effects in the long term. But it said it would not be “practical or cost-effective” to adapt the rails to manage the effects of temperature in the long term. What causes buckling? Metal can expand or contract depending on temperature. This creates forces that try to push and pull the railroad out of shape. Railroad engineers try to prevent this by using sleepers and ballast. Network Rail says measures used in other countries include using a solid concrete slab to hold the higher forces – but warns that “slab rails cost around four times more than standard ballasted rail”. He said: “The movement of trains also creates forces on the track. The higher the speed, the higher the power of a train. “When thermal expansion forces are high, trains deliberately slow down to reduce the additional forces they exert on the rail.” When will UK infrastructure improve to cope? Mr Shapps said rail and road problems would continue for decades during extreme heat. Asked how long it would take to upgrade the existing rail infrastructure to make it more resilient, he told Sky News: “Decades, actually, to replace it all. The same with the asphalt on the roads.” He told BBC Breakfast: “We’ve seen significant travel disruption, we’re probably going to see the hottest day on record in the UK today and the infrastructure, a lot of it built in the Victorian era, just wasn’t built to withstand this type of temperature – and it will be many years before we can replace the infrastructure with the kind of infrastructure that could, because the temperatures are so extreme.” Asked if the transport system could cope with the weather, he said: “The simple answer right now is no.” Workers repairing the runway at Luton Airport Credit: ITV News Luton Airport had to divert flights on Monday after high temperatures melted the surface of its runway. The airport said it discovered a defect in the surface that was being repaired and apologized to passengers. Want a quick and special update on the biggest news? Listen to our latest podcasts to find out what you need to know…
