Improving the water quality of the River Crane

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Polluted outfall

[Above: A stock image of a polluted outfall, before misconnection investigations have taken place] 


Over 270 appliances, including washing machines and baths, no longer empty their contents into the River Crane and its tributaries, thanks to 12 months of hard work by Thames Water and the Environment Agency.


Following extensive detective work at over 5,000 properties, across five west London boroughs, 13 outfalls, where surface water enters the river, have been significantly improved.  


This means that the dirty water is now correctly destined for foul sewer pipes and Thames Water’s local treatment works, instead of flowing into drains only meant for surface water and then out into local watercourses.


The Environment Agency suspected that properties had incorrectly connected their wastewater pipes (for dirty water from appliances like kitchen sinks, washing machines, baths and showers) into the surface water pipe network, prompting investigations by Thames Water across the boroughs of Hounslow, Hillingdon, Richmond, Harrow and Ealing.


By close of the investigation, the team had identified 271 misconnected appliances, ranging from baths, to dishwashers and washing machines.


Ruta Akelyte, from Thames Water’s environment team, said: “No one wants foul water from homes emptying directly into their local river, so it’s great that we’ve managed to improve the water quality in the River Crane.


“We’ve still got more to do though to trace more misconnections in our region. That’s why it’s really important that anyone having an extension built, or is carrying out plumbing work, employs a reputable plumber.”


Mark Craig, from the Environment Agency, said: “The Environment Agency is really pleased that Thames Water’s hard work has helped clean up this watercourse. Washing machines, showers and baths were regularly discharging into the River Crane and reducing the water quality.


“To ensure that this doesn’t happen again in the future we encourage homeowners to check that they are connected right – you can find information on how to do this on the ConnectRight website (”


Across the Thames Water region, plumbing mistakes can result in one in 10 households misconnecting waste appliances to the surface water system – the equivalent of over three Olympic-size swimming pools of wastewater wrongly entering the region’s rivers and tributaries every single day.


The Thames Water misconnections team work in close partnership with the Environment Agency to trace and reduce the number of misconnections, but it is predicted that there are at least another 60,000 misconnections still to be found.