water rises

The report, Vulnerability to Heat Waves and Drought: Adaptation to Climate Change, by the environmental consultancy AEA and a team from the University of Surrey, warns that water is becoming scarce as a result of climate change and increased consumer demand. An estimated four million households in the UK are already "water poor", according to the report, and the situation is likely to worsen.

Joseph Rowntree Foundation, one of the largest social policy research-and-development charities, says that low-income households are at particular risk because of new methods being introduced to increase the efficient use and distribution of water. It defines "water poverty" as when households spend 3% or more of their income on water bills. Water companies are moving away from flat-rate fees to new charging models that bill customers with steadily higher prices according to how much water they use. The report warns that this could create affordability problems for some low-income households and lead to "water poverty".

"We currently waste a lot of water, so on one level it makes sense to encourage greater efficiency by charging people depending on how much water they use," the report's lead author, Magnus Benzie said. "But some tariffs can put unfair pressure on households that cannot reduce their water consumption, either because of household size, medical needs or an inability to invest in water-efficient appliances."

Water poverty is expected to be acute in "urban heat islands" – built-up environments that retain heat more than surrounding areas. Failures to anticipate the threat posed by climate change can be fatal. The authors point to the heatwave across Europe in 2003 that led to more than 30,000 premature deaths.