Cleaning up Wimbledon Park Lake

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Wimbledon Park Lake

[Above: Stock image of a polluted surface water outfall]

To protect precious green spaces in Merton, Thames Water is reminding households and businesses to ensure drains are properly connected. 

The reminder comes as the UK’s largest water and wastewater company’s work to protect Wimbledon Park Lake has been recognised by the Environment Agency. 

The lake, a beauty spot for locals, has been suffering from poor water quality over the past two years owing to a combination of fly-tipping and misconnected pipes, with water which should be destined for sewage works instead ending up in the watercourse. 

Gary Waddup of the Environment Agency said: “Thames Water have carried out important work identifying and rectifying misconnections in this catchment following our requests to clean up the surface water drain that enters Wimbledon Park Lake. The Lake is a much loved community asset and this project is an excellent example of the Environment Agency and Thames Water working together to improve water quality.”

Ruta Akelyte, from Thames Water’s environmental protection team, added: “There are two separate drainage systems in this area, one for rain water and one for waste water. That’s why it’s vital domestic and commercial drains are connected correctly so that waste water from people’s sinks, baths and dishwashers does not end up harming the environment.”

Across the whole Thames Water region, private plumbing mistakes account for a significant amount of pollution to watercourses, and investigations have found misconnections – private plumbing mistakes which often happen during the construction of new buildings or the refurbishment of older ones – can be as high as one in every 10 properties. 

Ruta added: “Since 2015 we’ve identified more than 5,000 private properties with misconnections, totalling almost 10,000 waste appliances, which is the equivalent volume of 50 Olympic-size swimming pools of wastewater wrongly entering our region’s waterways over the course of a year.”

Pipes that are incorrectly plumbed to a surface water drain are illegally misconnected and the responsibility rests with the owner of the respective property to put things right. Therefore, households and owners of commercial premises should always choose a competent plumber for any drainage work.

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