Gardens in Blackbird Leys, Oxford, were swamped in sewage after a pumping station broke, following 20mm of weekend rainfall.

Thames Water had to take emergency action after Minchery Farm pumping station was "inundated" with water and put out of action.

Engineers were forced to pump sewage into Northfield Brook in Greater Leys, while homeowners living nearby were left to clear up stinking effluent from their gardens.

Last night Thames Water said a "rigorous clean-up operation" was under way.

Blackbird Leys pensioner Jimmy Hayes' garden was flooded with sewage for the third time in a year, after rain pushed raw sewage back through his drains.

Mr Hayes, 69, was left with a film of filth covering his back garden in Windale Avenue.

He said: "It is raw sewage. It looks like a grey slime.

"On Sunday, the smell was pretty awful - and, apart from the stench and stink, it is a health hazard.

"Sometimes my grandchildren come here. I could not let them out in the garden to play now."

The pumping station - which transfers household waste to the main sewer network and then on to a treatment works - was blocked because a high volume of fat and oil had caked the inside of sewers.

Its electrical equipment failed after water breached the doors, shutting down the entire system.

Thames Water said it was "overwhelmed" with calls from across Oxford, and sent emergency crews to deal with backed-up drains in Old Marston, Kennington and Blackbird Leys.

But angry homeowners have demanded the company takes action to ensure a similar situation does not happen again.

In Blackbird Leys, Clive Mitchell, 68, said a rain gauge in his garden showed 12mm of rain had fallen between midnight and 6am on Sunday.

He said Spindleberry Brook had gone from being a foot deep to six feet deep by Sunday morning.

Neighbour Walter Spencer, 71, said: "It has not been very nice. This has happened many times before."

Jim Shepherd alerted the Oxford Mail when he saw the sewage going into Northfield Brook.

Mr Shepherd, 58, said: "I couldn't believe what I was seeing.

"I was absolutely amazed.

"There was this rather nasty sewage being pumped into the brook.

"There were a couple of large pipes leading from the pumping station into the brook and where one of them wasn't working you could see this sludge going into the water.

"There were flies everywhere."

Last night Thames Water said it was not known how many homes were affected by sewage seeping out of drains.

A Thames Water spokesman said: "Engineers had to pump diluted sewage into Northfield Brook to enable emergency repairs to be carried out.

"This was under the full consent of the Environment Agency."

Mr Hayes said he had suffered similar overflows at least three times over the past year - and at least six times in the past five years.

He added: "I am fed up by their lack of concern.

"They should come and sort this problem out once and for all."