THE fast disappearing natural landscape of the British countryside could be making a small comeback in a secluded corner of the Tamar Valley.

A plan to breach the defences of the River Tamar and turn a 35-acre parcel of land at Cotehele into a wetland site is under way.

The site was reclaimed more than 150 years ago and is part of the Environment Agency's flood defence scheme for the area.

It could initially become a habitat for numerous invertebrates and birds such as the avocet and little egret, which thrive in muddy wetlands. Other birds will follow as the reed beds become established.

The land, owned by the National Trust, is part of the Cotehele estate — a mile downstream of Calstock. It is called Hayemarsh and lies between Morden Stream and Halton Barton.

Lewis Eynon, property manager at Cotehele, said: 'It is quite unusual to "un-reclaim" land, but we feel it is necessary to re-create the historic wetland sites.'

Hayemarsh was reclaimed some time in the early part of the 19th century and the relatively low grade grassland used for grazing.

Since 1947, it has belonged to the National Trust and is maintained by the Environment Agency as part of the flood defences.

Once the defensive bank is breached the grass will die off and the common reed will colonise the river silt being built up.

It is thought that for the first five years the area will be more than 90 per cent mud flats. But after about 10 years the reeds will take most of the site.

'It's not going to happen over night,' said Mr Eynon. 'It's like planning a woodland and the real impact won't be obvious for many years.

'It will look quite different for a while, but this is a long-term scheme — we are looking 20 years ahead. We are going to own this land forever and are looking at something sustainable.'

There are a lot of interested groups concerned with the effect on the navigable channel, the hydrological effects on silt deposition, scouring and erosion in the entire estuarine complex and on other habitats in the area.

The Queen's Harbour Master, the Environment Agency, English Nature, the Tamar Valley Countryside Service and the Estuaries Officer have all been involved.

Mr Eynon said there was unlikely to be a negative effect, but they were not taking the possibility lightly.

'We, nor any of the other parties, want any significant adverse impacts,' he said.

Apart from the ecological benefits of re-creating the wetland, the National Trust is hoping, in time, to create some access for visitors, including those with disabilities.

The project is still in its early stages. A management plan will be drawn up over the winter and detailed costs considered.

If the various issues still to be addressed are resolved it is hoped that work could begin in 2002.