A forensic approach

Scientists are completing the country's first ever comprehensive study of DNA extracted from water samples in a bid to further improve bathing water quality in the South-west.


Wessex Water is leading a project to complete microbial source tracking (MST) in Weston-super-Mare, Burnham-on-Sea, Minehead and Watchet.

The research involves isolating the DNA of bacteria found in bathing water samples so that it can be analysed to help determine what animal it might have come from including cattle, birds and humans. MST has been used in areas such as forensics for a number of years, but it is new to the water industry.

The study is being completed ahead of the revised Water Bathing Directive, which comes into force in 2012 and involves tightening the current standards.

Ruth Barden, Wessex Water’s environmental regulation manager, said: “Bacteria sometimes found in bathing water can come from many different sources which in the past have been extremely difficult to identify. But this scientific technique combined with other survey work we are using will help us eliminate this issue.

“Once we have identified the source of bacteria we can work with the Environment Agency to help focus efforts on any areas that would benefit from improvements where activities may be influencing water quality.”

The study has involved a series of sampling sessions during last year’s bathing season. Samples are taken close to the water’s edge, 30cm below the surface.

The samples are tested for bacteria at Wessex Water’s laboratory in Saltford. Additional sampling is carried out at a specialist centre near Cardiff for MST testing to determine where bacteria found may have come from.

Barden added: “We hope the results of these innovative surveys will give us the opportunity to invest in work which will bring maximum improvements to water quality.”

MST testing will take place for a further two bathing seasons and may continue so that the company can monitor how any new assets they invest in to improve bathing water quality are performing.

According to Wessex, it is being used alongside traditional analysis methods to safeguard the environment for the future.

Action inspires action. Stay ahead of the curve with sustainability and energy newsletters from edie

Subscribe