A prominent society is expecting a big turnout tonight at a meeting to rally opposition to the controversial Hampstead Heath dams project.

The Heath and Hampstead Society has branded the scheme the biggest threat to the Heath since the 1800s and tonight it will call on the public to get behind its battle to oppose the works.

Residents will have the opportunity to voice their views on the £15million scheme at St Stephen’s in Rosslyn Hill, Hampstead, from 8pm, before a formal consultation is launched by tomorrow.

The project is being pushed by the City of London Corporation, which manages the Heath, and would see parts of the park’s treasured landscape transformed, destroying cherished views, in order to strengthen dams at each of the ponds.

The City says it is necessary to protect against the threat to life posed by the small possibility of a catastrophic, “one in 400,000 year” storm. The Corporation has said nearly 1,500 people in downstream communities like Gospel Oak could drown.

But the Heath and Hampstead Society has accused the City’s engineers of exaggerating the risk, saying the dams have never been breached in their 300-year history and that there have never been any flood-related fatalities on the Heath.

It also argues that the City is following a misguided reading of its legal obligations, and that it has failed to properly explore the alternatives.

The society’s chairman Tony Hillier recently wrote: “We are deeply concerned at the direction being taken by the City.

“We believe these proposals are a much greater threat to the Heath landscape today than the works proposed by the LCC in 1895 that brought the society into being.

“We urge the City and their advisers to stop ignoring a whole series of reasons why they can still soften the designs to make them more appropriate for this very special landscape.”

He also said that the latest designs for the dam rebuilding project will “permanently disfigure the Heath in a way which is not necessary”.

The public meeting is at St Stephen’s in Rosslyn Hill, Hampstead, from 8pm tonight.