Britain’s railway network is preparing for increasingly severe weather as a developing El Niño raises the possibility of record-breaking heat in 2027. Extreme temperatures have already disrupted rail services across the country, forcing operators to reduce train speeds and alter timetables. During the UK’s fifth heatwave in August, two trains derailed within 24 hours, highlighting the growing challenges that climate extremes pose to transport infrastructure.
One major problem is that much of Britain’s rail infrastructure was not designed for very high temperatures. Xueyu Geng, professor of ground engineering at the University of Warwick, explained that heat can place stress on tracks, surrounding ground and overhead electrical lines. As temperatures rise, infrastructure designed around Britain’s historically moderate climate may become increasingly vulnerable.
The developing El Niño could create additional challenges. The Met Office expects the Pacific climate pattern to become exceptionally strong, potentially producing Pacific sea surface temperature anomalies exceeding 3C. Britain could experience a combination of prolonged hot and dry periods alongside wetter, stormier conditions, requiring infrastructure capable of coping with very different weather extremes.
Experts argue that long-term adaptation must therefore accompany routine maintenance. Britain could learn from countries accustomed to greater temperature ranges. Rail systems in Spain, for example, operate in temperatures reaching around 45C, while infrastructure in Saudi Arabia can function at approximately 55C. Engineering techniques such as adjusting the pre-stressing of tracks could help Britain’s railway infrastructure withstand higher temperatures while retaining its ability to operate during extreme cold.
Network Rail has already increased investment in climate resilience. In 2024, its projected five-year spending on climate, earthworks and drainage increased fivefold compared with the amount allocated in 2019. Experts nevertheless argue that further adaptation is necessary as climate change alters the conditions under which infrastructure must operate.
Preparing for heavy rainfall is another priority. Recommended measures include clearing drainage systems, inspecting culverts, monitoring earthworks and managing vegetation, particularly in locations with histories of weather-related failures. Changes in soil moisture can also affect track stability and force operators to impose speed restrictions, potentially causing significant timetable disruption.
Researchers emphasize an important distinction between maintenance and adaptation. Clearing an existing drain may reduce the risk from an approaching storm, while redesigning the drainage system with greater capacity could protect infrastructure against more intense rainfall for decades. Britain will increasingly need to pursue both strategies simultaneously.
Network Rail says improving resilience to extreme weather remains an ongoing priority. Its current plans include a £2.6 billion programme covering track maintenance and renewals, drainage, earthworks, overhead power systems and other improvements. Monitoring and predictive technologies are also being introduced to identify potential problems earlier.
The challenge facing Britain’s railway system illustrates a wider problem for infrastructure built around historical climate conditions. As heatwaves, intense rainfall and storms become more disruptive, long-term engineering standards may need to change. Building resilience will require not only maintaining existing infrastructure but redesigning it for the broader range of weather conditions expected in the decades ahead.