ENVIRONMENTALIST Dr David Bellamy yesterday launched a project replacing some of Britain's disappearing wetland that could help a rare visitor return to the North-East.

Using a mechanical digger, Dr Bellamy dug the first hole to transform an old sewage treatment works into a 15-acre wetland, extending Durham Wildlife Trust's reserve at Low Barns, Witton-le-Wear.

The trust hopes the site will become a home for the extremely rare bittern, a bird with a distinctive booming call which lives in reedbeds.

Last winter, a single bittern spent four months at the reserve, proving a big attraction for birdwatchers and other visitors because there are only about 20 breeding birds in the country and none has bred in County Durham for 50 years.

Reedbeds are among a range of habitats being created through a £270,000 year-long project being managed by the trust and Northumbrian Water.

About 75 per cent of the country's wetland has been lost to provide roads, industrial sites and housing land during the last century.

This land became available because improvements to sewage treatment in Wear Valley meant that the water company no longer needed its three-acre works near the reserve.

Funding of £190,000 is coming from the Mineral Valleys Project from the Heritage Lottery Fund, while Northumbrian Water contributed £40,000, donated the land and is paying for a project manager's post. English Nature and the Environment Agency are also supporting the scheme.

Bird watchers will be able to use two new hides overlooking the wetlands, which are reached by improved access roads and paths.

Dr Chris Spray, Northumbrian Water's environment director, said: "This is a really imaginative solution to the problem of what to do with an abandoned sewage treatment works."

Durham Wildlife Trust project manager David Long said: "The support of the Heritage Lottery Fund will enable us to extend and improve the wetland habitats at the nature reserve.

"Wet meadows and reedbeds are two of the most threatened habitats in the county and are key targets for creation and enhancement in the Durham Biodiversity Action Plan.