HOMES on an Oxford estate have been pumping waste into a nearby nature reserve for months.

Thames Water has revealed it tracked mystery pollution at Lye Valley Nature Reserve back to properties on the Slade estate in Headington.

They had been ‘misconnected’, meaning pipes which should have sent water for treatment were in fact ending up in Boundary Brook - a plumbing mistake the water company estimates affects up to one in ten households.

As a result, waste from washing machines, dishwashers, sinks and – worst of all – toilets, was flowing towards the scientifically important habitat.

Oxford Mail:

Waste from headed towards the brook Pic: Thames Water

With more than 800 homes and businesses connected to the pipe system, Thames Water engineers had to work with residents to find the two properties which were causing the problem.

Thames Water’s Stephen Barry said: “After several months of hard work, we’re delighted to have this resolved. The waste coming into Boundary Brook could have had a real long-term environmental impact so we were determined to get to the bottom of this complex issue.

“Misconnections can be a big problem for local rivers and streams so we would urge anyone having a new appliance, such as a washing machine installed, to make sure they check it has been connected correctly.”

Across the Thames region, the water company estimates the equivalent of an Olympic-size swimming pool of wastewater enters the region’s rivers and streams every day from ‘misconnected’ pipes.

Responsibility for the issues lies with the property owner.

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Robert Davis, an environment officer for the Environment Agency in Oxfordshire, added: “The Environment Agency welcomes the work done to identify several sources of third-party pollution leading to Lye Valley Nature Reserve, and clear them.

“The rich variety of local wildlife will benefit from better water quality, which contributes to a nicer environment for people to visit.”

It comes after the water company was criticised by campaigners last month for allegedly overusing Combined Sewer Overflows (CSOs) and polluting Oxfordshire’s waterways. CSOs are used to stop sewage backing up into homes during heavy rainfall, but the Windrush Against Sewage Pollution (WASP) has found faults in the system which it says mean sewage works are overloaded.

READ AGAIN: Thames Water receives record fine for polluting waterways 

Thames Water, which was last year fined a record £20m for pumping untreated sewage into the Thames, does not monitor all of its 650 overflows all of the time, but said it plans to start doing so ‘by 2020’.

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