A family fears a stream which gushes from under their home could undermine the foundations of the building.

The rear yard at Michelle and Andy Corcoran's home in Hali-fax Road, Keighley, has already subsided. Stones have come lose from a buttress supporting the yard and part of the retaining wall has been pushed out.

The couple suspect the water is flowing under Halifax Road and beneath their terraced home, but its source remains a mystery.

Mrs Corcoran, 31, and her 32- year-old husband have lived in the house about nine years. The property is also shared by Mrs Corcoran's mother Nadine Peck, 55. They say the flooding problem has got worse since November 2000.

It has been investigated by Yorkshire Water, which says the water is not from the mains. Bradford Council is also involved in finding the source of the flow.

"There has almost always been a trickle from that area but now it's a torrent," said Mrs Corc-oran. "The houses are built on sandstone and we are aware what water can do to sandstone - we're worried it will wash away the foundations."

A Council spokesman said: "There is an ongoing investigation to discover the source of this water."