More than a million people in Britain could be left without piped drinking water in the event of a major infrastructure failure, according to a revised government risk assessment that has sharply escalated its warnings within a year. The National Risk Register, published in July, now rates the likely impact of a major water infrastructure failure as 'catastrophic’, up from 'minor' the previous year, and estimates a 5% to 25% probability of such a failure affecting a large urban area within the next four to twenty years. Paul Netherton, former police national lead for resilience, said climate change and hostile state aggression were both contributing to the heightened risk, warning that a hostile state could exploit public anger at Britain's privately-run water companies by targeting supplies with a cyberattack or contamination. 'There are not enough pumping stations and treatment plants to cope with the strain on the system’, he said, with any major failure risking evacuations, school closures, and disruption to hospitals.