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

Already the rear yard at Michelle and Andy Corcoran's home in Halifax Road, Keighley, has subsided.

Stones have come loose from a buttress, which supports the yard, and part of the retaining wall has been pushed out by about two feet.

They 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 and, apart from a short period in the summer, water has been constantly flowing.

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

"There has almost always been a trickle from that area, but now it's a torrent," said Mrs Corcoran.

"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."

Mrs Peck added: "We could live with it if it just remained a small amount, but it's getting stronger and stronger.

"It's forming a small lake under the retaining wall and some of the stones in the buttress have moved. We have spoken to Bradford Council who said they were at a loss to know where the water was coming from."

A Bradford Council spokesman said: "There is an ongoing investigation to discover the source of this water and the council will continue its attempts to resolve the problem."