Every constituency projected to be at greater risk, with many areas likely to be uninsurable, Guardian investigation finds

Millions more homes in England, Scotland and Wales face devastating floods, and some towns may have to be abandoned as climate breakdown makes many areas uninsurable, a Guardian investigation has found.

New analysis from the insurance industry, seen by the Guardian, reveals the extent of concern in the sector, with bosses warning that large swathes of housing and commercial property in densely populated areas will be at greater risk.

Severe Flooding, Against a Background of Wind Turbines: November 2012, Tyringham, Bucks. (Image: T. Larkum)

Severe Flooding, Against a Background of Wind Turbines: November 2012, Tyringham, Bucks. (Image: T. Larkum)

Separately, experts have said that some towns may need to be abandoned as homes and businesses struggle to get insurance in areas repeatedly battered by storms and rising sea levels.

Densely populated areas including London, Manchester and parts of north-east England, are likely to be worst hit. Experts also say London’s flood defences need to be updated urgently to protect the capital from devastating floods.

“The findings are stark,” said Jason Storah, chief executive for UK & Ireland general insurance at Aviva, which published the analysis. “Millions more properties will be at risk from flooding, with rising temperatures, increased urbanisation and inadequate drainage.”

Tenbury Wells, a market town in Worcestershire, has become the first in the country to find that its public buildings are uninsurable. The town has historically suffered damaging floods about once a decade, but in the past six years people there have been hit four times.

Read more: The Guardian