The UK's rail network is preparing for potential widespread disruption as thunderstorms are forecast to bring heavy rainfall across parts of the country. Rail bosses have warned that drought-hardened ground, a result of recent record-breaking heatwaves, could prevent rain from soaking into the soil, leading to surface water and potential flooding on tracks.
This comes a week after a passenger train derailed near Lewes, East Sussex, amid extreme heat, resulting in 30 injuries. The Met Office has issued thunderstorm warnings for the coming days, with the anticipated rainfall marking the first significant precipitation for many areas of Britain after months of soaring temperatures.
Nearly three-quarters of England and all of Wales are currently experiencing drought conditions. July rainfall totals were significantly below average, with some regions receiving as little as 1% of their typical amount. Experts caution that even with the return of rain, it may take weeks of above-average precipitation to reverse the drought conditions.
When floodwater rises above rail levels, speed restrictions or service suspensions are typically imposed. Network Rail stated they are not predicting major disruption in the short or longer term but emphasized they are not complacent and are preparing for a potentially warm and wet winter, in line with climate change predictions.
The rail network has been under heightened scrutiny following two derailments within a 24-hour period last week. In addition to the Lewes incident on August 13, which injured three people, another train derailed south of Wickford railway station in Essex without casualties. The eight-carriage Southern service that derailed near Lewes was traveling between Haywards Heath and Lewes when three carriages overturned. The incident occurred as temperatures exceeded 35 degrees Celsius (95 degrees Fahrenheit).
Network Rail has implemented measures to mitigate flooding risks, including deploying inflatable barriers, clearing drainage systems, and establishing water pumping stations at identified hotspots. Ongoing efforts also include raising trackside electrical equipment and monitoring embankment stability.
Academics have noted the increasing need to manage intense rainfall events as part of climate change adaptation. William Powrie, professor of geotechnical engineering at the University of Southampton, warned that downpours could disrupt services and that the engineering profession must find affordable solutions for handling large volumes of rainfall in short periods. He added that while some flood-prone areas have seen drainage improvements, preparedness will depend on the intensity and location of rainfall.
Dr. Ioannis Koliousis, associate professor of logistics and supply chain management at Cranfield School of Management, highlighted the impact of speed restrictions on rail capacity due to soft ground conditions following rainfall, which can lead to delays. John Lawrence, chair of the railway technical network at the Institution of Engineering and Technology, noted that while raised electrical equipment may not prevent track flooding, it allows for quicker restoration of services by preventing damage to essential equipment. He also mentioned ongoing innovation in drainage systems and embankment stability monitoring.