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Community partnership helps stop incorrectly plumbed domestic appliances from polluting the Hogsmill River

Tuesday 30th November 2021 11:59

A pipe flowing into a river

  • Thames Water, the South East Rivers Trust, ZSL and local volunteers have stopped over 400 misconnected household appliances from polluting the River Hogsmill.
  • Responsibility for fixing misconnections lies with the property owner and it is estimated that four per cent of properties in the Thames Water region have a misconnection issue.
  • Thames Water urges customers installing a new appliance or fitting new connections to make sure they’re plumbed in properly.
Hundreds of incorrectly plumbed washing machines, toilets and dishwashers that pollute rivers and streams have been uncovered by Thames Water, the South East Rivers Trust, ZSL and local volunteers.
 
Since 2016, the UK’s largest water company has worked with its community partners to identify more than 400 misconnected appliances along the Hogsmill River. 
 
All household goods should be plumbed into the wastewater sewer network, so the water can be taken away and treated. Misconnected pipes from household appliances can allow wastewater to get in to surface water sewers, which are designed to hold rainwater and drain into natural watercourses.
 
Community volunteers conduct Outfall Safaris which survey and assess surface water pipes found polluting the River. 
 
The Thames Water funded project, has helped raise awareness of the environmental impact caused by misconnected pipes while generating community engagement and interest in local rivers and watercourses. 
 
Richard Pumfrett, Thames Water’s environmental protection technical lead, said: “Household appliances which are connected to the wrong drainage pipe can have a serious impact on the environment. Most misconnections will have been done entirely by accident, but we would urge anyone installing a new appliance or fitting new connections to make sure they’re plumbed in properly. 
 
“The Hogsmill Outfall Safaris have been a great way to increase awareness of the issue, while involving the local community to take stewardship and help manage this wonderful chalk stream. Through this partnership we’re pleased to have found so many of these misconnections along the Hogsmill River and helped owners fix them, but we’re determined to keep doing more to ensure all wastewater is taken to our sewage works where it can be safely treated.”
 
Joe Pecorelli, conservation project manager at ZSL, said: “Urban rivers are precious and important places for people and wildlife. Working with Thames Water and local communities on Outfall Safari is one important means by which we can scale up our efforts to tackle the issue of pollution entering rivers via the surface water network but so much more needs to be done to bring rivers and their wildlife back to health.”
 
Jess Mead, project officer at the South East Rivers Trust, said: "The Hogsmill is one of just over 200 Chalk Streams in the entire world. It should be famed for its pristine waters but unfortunately it suffers from a multitude of issues including pollution from misconnected drainage. There's still lots to do to improve the health of the river for both people and wildlife, but we're extremely happy to see the difference the hard work of local volunteers has made in helping Thames Water to reduce pollution from misconnections."
 
Thames Water works with environmental groups, the Environment Agency and local authorities to identify points where pollution is entering waterways to spot possible misconnections. 
 
If pollution is spotted by the Hogsmill Outfall Safari volunteers, it is reported and catalogued on an app, which is then further investigated by Thames Water to identify the offending properties. 
 
Responsibility for fixing misconnections lies with the property owner and it is estimated that four per cent of properties in the Thames Water region have a misconnection issue.
 
Find out more information about misconnections and how to avoid them.
 
The Hogsmill River is a chalk stream and tributary of the River Thames. It flows from Ewell in Surrey through Old Malden, New Malden and Berrylands to the River Thames and is approximately seven miles long. 
 
Breakdown of misconnected appliances found following investigations of pollutions which were identified on Hogsmill Outfall Safaris

 

Appliance Number
Kitchen Sinks 92
Washing Machines 118
Dishwashers  40
Hand-basins  92
Baths 26
Showers 21
Toilets 15
Other 25
Total 429