RESIDENTS across Oxfordshire are being warned there is still a risk of sewers overflowing as a result of high ground- water levels.

Following the wettest year on record, January’s rain and snow has left rivers full and the water table so high, there is no capacity to absorb more water.

In many cases spring and river water is running directly into the sewers, which are designed to take only wastewater from homes and businesses.

This is putting the network under strain and Thames Water has been sending out its 6,000-gallon tanker lorries to pump away the excess water.

Dr Barnaby Smith, a spokesman for Wallingford-based Centre for Ecology and Hydrology, said: “In January the amount of rainfall for the river basin of the Thames was 62mm, which is just below average for the time of year.

“But the last nine months of 2012 were extremely wet, and that helped to create the high groundwater levels which remain and are not going away.

“The weather is not warm enough yet to start evaporating the groundwater – the evaporation season does not start until the end of March when air temperatures get significantly higher.

“There is still lots of standing water on the fields, much more than you would expect for this time of year.”

Frank Dumbleton, 67, of Main Street, Chilton, said Thames Water staff had made repeated visits to the village in the past two months because of sewage covering The Lane.

He said the sewage has not got into people’s homes, but added that there has been repeated contamination of the lane.

Thames Water spokesman Simon Evans said the company has also been sent to Standlake High Street near Abingdon to suck out excess flows from overloaded sewers and prevent homes and businesses flooding with sewage.

Tanker staff have also been working in Brize Norton.

He added: “Once groundwater flows above the level of the sewers there’s the possibility of sewage flooding on to roads and, potentially, into houses and gardens.”

Sustainability director for Thames Water, Richard Aylard, said: “While we recognise that having tanker lorries running 24/7 is not ideal, particularly on narrow country lanes, right now this is the only way to stop some of our customers’ properties flooding with wastewater from our overloaded sewers.

“We will continue tankering in the areas worst affected for as long as is necessary. “Flooding tends to ease when the rain stops only to return when it rains again. That is because the underlying cause – high groundwater and full rivers – remain.

“This means, potentially, for the rest of the winter months, flooding-related problems could recur at hotspots, particularly after any significant rainfall.”