IFFLEY residents have spoken of their surprise that a nearby brook was being mistakenly used as an open sewer.
Boundary Brook, a tributary of the River Thames, was contaminated by waste from toilets, sinks, showers and washing machines.
Appliances had been incorrectly plumbed in around the Campbell Road area, said Thames Water, which has now fixed the issue.
The appliances were sending water into the surface water drains instead of the sewer network.
The firm said such plumbing problems are common and affect about one in 10 homes.
After detecting the high levels of pollution in November 2011, the firm surveyed 2,400 homes in the area.
Campbell Road mum-of-one Eleanor Crichton, 35, said: “At one point you could definitely smell it and you could tell something was wrong. Thames Water haven’t really communicated with us to say what was going on, but the trucks have been and fixed it now.
“That was noisy, but nothing like when they were pumping out the sewage.”
Neighbour Duncan Dingel, 30, a builder, said: “It’s not good. My dog goes in that brook when we go for walks and then she comes back into my home. I presumed it was clean water, so that is concerning.”
Thames Water’s Andrew Broadbent, who helped fix the problem, said: “The thought of human waste, cooking fat and dirty water going straight into this brook is frankly disgusting.
“We’ve got a massive job still to do to trace more of these misconnections.
“Anyone having extensions built or carrying out plumbing work should employ a reputable plumber and know exactly where their waste water is heading.”
The firm said “detective” work that started in June 2012 included hanging wire cages inside the drain network to collect waste samples.
It used video cameras and placed green-coloured dye into residents’ toilets to trace flushed water.
The firm worked with Oxford City Council and The Environment Agency, which said the problems reduced water quality for wildlife in the area.
Spokeswoman Jessica Bates said: “To ensure that this doesn’t happen again in the future we encourage homeowners to check that they are connected properly.”
Janet Keene, group secretary of Oxford Urban Wildlife Group, said the news was “serious and disturbing”.
In all, appliances wrongly plumbed in were:
- 22 hand basins
- 21 kitchen sinks
- 20 washing machines
- 19 toilets
- 17 showers
- 14 baths
- 13 dishwashers