A conference has heard how urban drainage systems have struggled to cope with the heavy rainfall of recent weeks.
Research presented to the Royal Geographical Society event in Edinburgh warned of the on-going flood risks to millions of city dwellers as the run-off resulting from intense periods of rain can quickly overwhelm systems, causing surface water to build up in low-lying areas.
From modelling of at-risk areas in Glasgow, Belfast and Luton, the work also concluded there is a slightly increased risk of rain-related or ‘pluvial’ flooding for people in vulnerable social groups. For example, lower income groups and renters are more at risk than because tend to live in low-lying areas around town centres dominated by higher density terraced housing and flats.
Dr Alastair Geddes of Dundee University said: “Existing flood risk assessments are based on the number of properties at risk as opposed to the number of people. This approach downplays the impact on people, and in particular potentially vulnerable groups such as the elderly.
“We estimate that around two million urban residents are exposed to this kind of flood risk and that this applies more so to several vulnerable social groups.
“The number at risk is expected to increase by more than half, to 3.2 million people, by 2050, largely the result of regional population growth, although changes in precipitation caused by climate change will also be important.”
The research concluded that population change has the potential to put three times more additional people at risk than climate change.