Tests conducted on the most used stretch of the River Thames, that which flows through Kew, Putney and Barnes, have shown the presence of high levels of bacteria and viruses. These pathogens can cause infections such as gastroenteritis and lead to nausea, diarrhoea or abdominal pain. Although only 18 people out of about 1200 leisure users have reported such symptoms, health experts believe there are many unreported cases. Large numbers of people use the river for recreational activities such as rowing, canoeing and fishing, and so the health risk to the public is high and imminent. Visitors who have built no immunity to the pathogens are most at risk, as are children and the elderly. Dr Susanne Surman-Lee, of the government’s Health Protection Agency, advises that people should ‘wash their hands regularly after using the river, particularly before eating or drinking, and try not to swallow any water if they should fall in’. With the approach of the 2012 Olympics, health agencies have warned competitors not to train on the river. As well as putting human health at risk, the pollutants also kill plants and fish, reduce biodiversity and decrease the aesthetic and general quality of the water.
The contamination seems to be the result of a discharge of untreated sewage into the river following heavy rainfall. When treatment works are unable to cope with excess surface water, such as after heavy rain, water is discharged, unfortunately along with untreated sewage. Recreational users of the river are thought to be at risk of infection for three or four days after such heavy rainfall. Some believe that climate change and the associated unpredictable weather will lead to increased pollution of this kind. Jenny Bates, the London campaigns co-ordinator for Friends of the Earth, says ‘the solution is for the Thames interceptor tunnel to be built urgently and for the government to introduce a strong climate change bill’.
http://www.guardian.co.uk/environment/2007/sep/27/pollution.uknews (27/9/07)
