Water drawn from ancient aquifers across Britain is steadily becoming unusable because of widespread pollution from fertilisers, pesticides, oil and other contaminants. The warning appears in an Environment Agency report to be published tomorrow and follows countrywide testing of 7,300 groundwater supplies, which in some regions provide up to a third of available tapwater.

The report - Underground, Under Threat - highlights widespread leaks and chemicals spread on to farmland, known as diffuse pollution, as the greatest threat to groundwater, and estimates 81% of sites in England and 35% in Wales are at risk of failing water quality standards. Poor water quality has already led to the closure of 146 groundwater sources in the past 30 years, leading to the loss of at least 425,000 cubic metres of water every day, enough to supply nearly 3 million people. But growing urbanisation and rising pollution is putting the supplies at even greater risk, the report claims.

Previous tests found pesticide contamination in more than a quarter of groundwater sites. The latest tests also revealed problems with nitrate contamination from fertilisers and traces of drugs such as the anti-bacterial triclosan, that might kill off microbes that help break down pollutants. Other chemicals, such as fuels, fuel additives and solvents were also detected, but are too modern to know what their effects will be, the report adds.

"Groundwater is very vulnerable to pollution and while it takes just a few careless moments to pollute or contaminate, it can take decades or even centuries to recover. Thats why we need to do what we can to stop it from being polluted in the first place," said Tricia Henton, environment protection director at the Environment Agency.
(By Ian Sample, The Guardian, 18/10/2006)
http://www.guardian.co.uk/science/story/0,,1924734,00.html?gusrc=rss&feed=18