Upstairs Downstairs TV star John Alderton has become embroiled in a row over basement developments – claiming that plans for a neighbouring house could destroy his historic home.

The Hampstead actor, who also starred in the film Calendar Girls, made an impassioned plea to a planning inspector at a meeting last week to stop plans for a neighbouring house in Redington Road to be demolished and rebuilt with a basement.

The 71-year-old, who lives with his actress wife Pauline Collins, said yet another basement in the area could cause an underground dam to form near his Grade II-listed house.

He claims the resulting build-up of water from underground streams could wash away the foundations of his home.

Camden Council planning officials turned down the application last year, saying it would have a negative impact on Mr Alderton’s home and the Redington And Frognal Conservation Area.

In a letter to the Planning Inspectorate Mr Alderton, said: “My shallow foundations are likely to be exposed with major damage. My house could become an island between two rivers.”

Mr Alderton’s house is flanked by basements.

Geologist Dr Michael De Freitas, a research fellow at Imperial College London, wrote a report to back up Mr Alderton’s claims.

But Dr Shon Williams, a specialist in retaining water and ground movement, criticised the report at the planning appeal on Thursday and accused Dr De Freitas of having ‘‘his own agenda against basements”.

“The idea that the basements will give this big damming effect is just quite frankly incorrect,” said Dr Williams, who helped with the basement impact assessment on the plans.

“The reality is, this water could flow around it. There is a lot of room for water to flow. To me, that’s not damming the water.”

Last year the Ham&High reported that part of Redington Road, near the Upstairs Downstairs actor’s house, gave way to reveal a large underground cavern.

The planning inquiry heard the area has suffered such problems for more than 20 years.

The planning inspector will now decide whether to overrule the decision to refuse planning permission.