Residents and councillors in West Hampstead have united to get to the bottom of a spate of flooding incidents over the last six months.

Reports that basements and cellars of homes in Fordwych Road and the West End Lane area have been flooded with clear water have been circulating since December last year.

One potential cause for the flooding is the poor condition of water mains in the area.

On Sunday a pipe was damaged in College Crescent, Swiss Cottage, at 10.30am, leaving 7,000 homes without water for almost 11 hours. No homes were reported to be flooded.

The recent surge of incidents has prompted Cllr Keith Moffitt, who represents West Hampstead, to arrange for Thames Water to meet locals to discuss potential causes.

Sue Measures, who lives in Fordwych Road, said her cellar has been flooded four times since February – with the water level reaching 3ft at its highest.

She said: “I was shocked. I’ve lived in this house since 1975 and, to my knowledge, the cellar has never flooded before this year.

“There are three other known properties on this road which have had flooding and we are all very concerned.”

A claim that recent deep basement developments could have altered the path of old rivers to cause the flooding was dismissed at a Camden Council culture and environment scrutiny committee meeting last Wednesday.

Harold Garner, the council’s sustainability manager, said: “There is nothing a basement could do to alter the route of a river. If it was that, they would be carrying sewage into the basements and cellars and the water identified appears to be clean.”

After the meeting, Mr Garner pointed to saturated top soil due to heavy rainfall or burst water mains as a potential cause.

He also suggested that the cumulative effect of historic basement developments, completed before the council introduced its requirement for a Basement Impact Assessment in areas of elevated groundwater, may have flooded cellars.

Cllr Moffitt said: “There are two separate issues – the condition of the water mains and flooding.

“There is a lot of concern. Thousands of new homes are being built in West Hampstead and there is concern that the infrastructure cannot withstand it. Cellars which have never flooded before are being flooded.”

The West Hampstead Area Forum meeting with Thames Water will take place on July 2 at Hampstead Synagogue, Dennington Park Road, West Hampstead.