Highgate campaigners have called for a halt to all basement expansions in Haringey until the council adopts an excavation policy in line with Camden’s.

The two local authorities slice through the middle of Highgate High Street, meaning that residents in Camden are subject to stricter building rules surrounding basement extensions than neighbours living just across the road.

Pointing to the “absurdity” of current practice, The Highgate Society has urged Haringey planners to adopt Camden’s policy.

Camden demands impact surveys on surface and ground water flow and structural stability before a basement extension can be given a green light.

Elspeth Clements, of The Highgate Society, said: “We have seen more than a dozen major applications lodged with Haringey over the past six weeks. We feel we have been fobbed off by Haringey Council.

“It is as if they are trying to move the massive houses of Bishops Avenue east to Highgate Village, which we don’t want.

“We have asked for a moratorium on basements until a coordinated policy is developed.”

Applications have clustered around Grange Road and Denewood Road, sparking fears that previous decisions to allow subterranean excavations in these and surrounding streets have opened the floodgates to more applications.

The calls come as Highgate resident Lord Bill Rodgers of Quarry Bank threw his support behind a Private Members Bill to curb basement developments, which critics say can cause structural damage and flooding to neighbouring properties.

Speaking in Parliament, Lord Rodgers said: “Last Saturday I walked through the streets that fall towards Hampstead Heath.

“For the most part they were covered by large Victorian and early 20th century houses with substantial gardens, but increasingly these are being demolished – a snowball effect – sometimes replaced by even larger ones, or they are being modernised with additional rooms and even swimming pools.

“As a result, they can disrupt the water table and drainage and can cause serious damage to nearby properties.

“Within a quarter square mile there must be a dozen significant residential building sites.”

Lord Rodgers, who has lived in North Road for 18 years, told the Ham&High residents and developers could be choosing basement excavations because extensions visible from the street are given greater protection in conservation areas.

He said: “Haringey planners might think this phenomenon only affects the village, but it can affect anyone at any time, whether it is a terrace, semi-detached or modern home.

“It is a growing issue and I hope that Haringey will keep up with the change.”

Marc Dorfman, assistant director of planning, said: “The council notes that other planning authorities are starting to develop planning guidance on this issue and Haringey will consider the need for this.

“Whilst this is being considered, we will continue to ensure water and land management issues are taken into account via application assessments and / or conditions, agreements or refusals.

“Building Control will also have a role to play in these matters if schemes are approved.”