A pond filled in more than 70 years ago is to be brought back to life as a nature reserve.

Conservationist David Wingate said the Eve’s Pond project is the largest attempted by the Buy Back Bermuda campaign, which was set up by the Bermuda Audubon Society and the Bermuda National Trust.

Dr Wingate said: “It will give Bermuda another place where a family can go out on a Sunday with their children, have a nice walk and see a bit of nature.”

Eve’s Pond was a tidal, saltwater pond in Hamilton Parish about 50 metres wide and 100 metres long, and linked to Harrington Sound through an underwater cave.

The pond was filled with sand from Flatts Inlet in 1941.

Buy Back Bermuda launched a campaign to purchase the property in 2005 and the sale was finalised seven years later.

“It has taken for ever to get the planning application ready for the restoration of this project because it was technically the most complex one we have undertaken in terms of restoration,” Dr Wingate said.

“Most of the pond restoration projects I have been involved in have involved ponds that have been filled in with garbage, so it is a matter of digging the garbage back out and recycling it until you recreate the wetland habitat.

“This one was not filled in as a garbage dump. It was filled in by the pumping of marine sediment from Flatts Inlet when they were deepening it.”

He added: “At the time, it was a mosquito-breeding pond. The attitude at the time was to fill it in because people didn’t appreciate wetlands.

“When the opportunity to use the sediment came, they rigged up a pipeline all the way from Flatts along what is now the Railway Trail.”

Dr Wingate said the land could not develop a healthy plant ecosystem because marine sand was used to fill it and the area was instead taken over by invasive species such as casuarinas.

“It is almost birdless and is a pretty sterile environment,” Dr Wingate said. “A few cedars and palmettos did recolonise the site, but very few, and there was a sea-level rise several years ago that killed a lot of cedars in all of the marsh basins.”

Dr Wingate said he did not know of any pictures of Eve’s Pond before it was filled in, but it was understood it was unique on the island as a tidal saltwater pond without mangroves.

The filling of the pond also caused damage to the Green Bay cave system, the largest underwater cave system on the island, which fed it.

To avoid further damage to the caves, the restored pond will not be linked into the cave system.

It is hoped to create a brackish pond similar to Spittal Pond, which would provide a habitat for migratory ducks and other wetland bird species.

Dr Wingate said:: “Most of our migratory waterfowl prefer fresh water spots, and of course fresh water is rare in Bermuda.

“This will still be tidal, but if it ends up at 15 parts per thousand, about halfway to salt water, it will be very close to Spittal Pond, which is our richest wetland area.

“You never really know until you have created the pond and you see how much the tidal flow is affected by the blockage of the sinkhole. We may be lucky and have it come out really close to fresh water, which would be ideal.”

Invasive species will be cleared from the area before the sand is removed and used to build an embankment along North Shore Road.

Dr Wingate said: “We want to do it as quickly as possible because it is going to look very ugly and raw simply because we have to remove all the vegetation before we can do the job.

“Once the embankment is built, we will immediately resoil it with soil we have salvaged and replant with an emphasis on endemics.”

A nature trail will also run through the site with an observation platform on the nearby hillside.