The impact of climate change on stability of slopes and coping with spending cuts has been highlighted by several speakers at today’s GE Slope Engineering conference in London.
“Climate change is happening but the problem is with uncertainty about the rate of change and how this will impact on long term slope stability,” said Loughborough University professor of geotechnical engineering Neil Dixon. “What is clear though is that while the mean values are increasing, the rate of extreme events is increasing at twice a rate and it these events that often have the greatest impact on slope stability.
“These heavy rainfall events and increasing rainfall over a longer period result in pore pressure changes that trigger instability but we also have the problem of aging structures, stress history and vegetation of slopes contributing to the problems.”
Dixon called for more research into how different rainfall patterns affect failure mechanism and pointed to the data on Mam Tor in Derbyshire, which has been collected since 1900 and continues to be gathered despite closure of the road in 1979.
“We need to work out whether it is more important to be proactive or reactive when it comes to dealing with landslides,” said Dixon.
Atkins technical director David Shilston, who is also president of the Geological Society said that the growing impact of the climate on slope stability means that hydrogeologists are needed to provide input into designs and analysis. “In the future a new discipline of engineering hydrogeology will be needed to meet the challenges,” he added.
Shilston went on to highlight the issue of managing this climate challenge and need for more research alongside meeting government targets for reduced spending. “Many areas of public spending have been cut by 30% in the last few years at a time when there is already a £9.5bn backlog in maintenance needs,” he said. “The impact of even a small slope failure can have a huge effect on infrastructure and the cost of recovery and repair.”