The findings were revealed in the Biennial Report on Reservoir Safety, based on two years of research from April 2005 to the end of March 2007.

Barbara Young, chief executive of the agency, said overall compliance with the Reservoirs Act 1975 had improved since the Environment Agency became the enforcement authority three years ago, but there was still work to be done.

“Dams and reservoirs store large amounts of our nation’s water, but if owners don’t monitor their condition and repair them when necessary, the huge amounts of water that they hold can threaten life and property,” she said.

Ms Young said the risk of dam failure was likely to increase because of more extreme weather events with climate change and an ageing reservoir stock.

According to the Environment Agency, the average age of dams in the UK is 110 years.

Legislative changes in the new report include better enforcement powers for reservoir emergency flood plans, funded powers to act at reservoirs with no owners, and mandatory post-incident reporting.

In October 2004, the Environment Agency became the enforcement authority for managing the safety of more than 2,000 reservoirs across England and Wales, which includes maintaining a register of reservoirs and making sure that undertakers have their reservoirs regularly inspected and repaired.

Ms Young said: “When we took over as the enforcement authority from local authorities, we faced a huge task.

“Since then, failure to carry out regular safety inspections has been cut by 80%, and over the past two years, we’ve issued 118 notices and prosecuted the undertakers at two reservoirs for failing to comply with the Act.”

A new Reservoir Safety Advisory Group is also being led by the Environment Agency to help with research and development.

The report is available on the Environment Agency’s website.

Dana Gornitzki

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