Land that will grow four tons of wheat to the acre and give good grazing is too valuable to be flooded with sewage effluent

For 300 years Neville Waters's family has farmed in the parish of Nash, just outside Newport in Gwent. But now their livelihood, like that of other farmers round them, is threatened by a scheme so idiotic as to be scarcely credible. The aim is to flood 1,000 acres of land - most of it with sewage effluent, some with sea water - to create a bird reserve.

To Mr Waters, the proposal is both practical madness and personal insult. If it goes ahead, he will lose 150 of the 270 acres which he farms, and his dairy herd may well go out of business. Apart from the fact that the scheme will cost pounds 6m or pounds 7m to implement, it will take pounds 500,000 a year to run, and reduce annual agricultural production by at least pounds 1m. It may also prove fatal to the rare plants and insects for which the area has been designated a site of special scientific interest.

The trouble has its origins in Cardiff Bay, 15 miles to the south west, where the Cardiff Bay Development Corporation is attempting to revitalise the waterfront. This project is now well advanced, and a key feature is the construction of a barrage across the estuary of the Taff and Ely rivers. This will turn the bay into a freshwater lake, flooding 500 acres of tidal mudflats and thus depriving several thousand wading birds, principally dunlin and redshank, of their feeding grounds.

Having fought the scheme unsuccessfully, the Royal Society for the Protection of Birds and other conservation bodies demanded compensation, and extracted a promise from the Secretary of State for Wales that alternative bird accommodation would be found.

The promise was backed by the European Commission, which threatened prosecution if the Government did not take action. Now, with four other areas considered and rejected, the axe is poised above the Gwent Levels, a strip of farmland along the coast south of Newport.

Nobody claims that this area is beautiful. Its western end is dominated by a vast power station, now closed down; inland, industrial development has sprawled out in a hideous barrier between the coastal plain and the hills. Nevertheless, the Levels are fascinating, for every acre bears evidence of man's 2,000-year struggle to control the ubiquitous water. Within a high sea-wall the flat fields are bounded by a network of reens (major watercourses) and lesser ditches. The oldest fields have shallow open channels, known as grips, running at right angles to the main ridge- and-furrow drainage system. Out of sight below ground are more modern drains filled with pipes and shingle.

The developers claim that the soil is very poor, and should be graded 3B. Local farmers retort that 80 per cent of the land in Wales is graded 4 or 5, and is rock or bog: the Levels are thus in the top 20 per cent by any reckoning. Land which will grow four tons of wheat to an acre and produce excellent grazing is far too valuable (they say) to be flooded with sewage effluent.

That is the imminent fate of the area known as saltmarsh. All drains will be blocked. Fields will be surrounded by bunds, or banks, of earth. Houses within the reserve will be ringed by individual bunds, with effluent lapping outside them from October to May.

Close to the derelict power station, ash has settled over the years to a depth of 12ft or 14ft in huge ponds specially built to contain it. These deposits contain boron, arsenic and other noxious materials, yet now some of them are to be excavated to a depth of 3ft so that they too can be flooded with sewage, in the hope of establishing a colony of - wait for it - bitterns.

There is clearly some risk that poisonous substances will contaminate the sewage effluent. Even advocates of the scheme admit that the habitat of the new reserve will be different from that of Cardiff Bay, and will not attract the displaced species.

Until last week, the Newport Planning Committee had been proposing to make a recommendation to the local council without even looking at the site. Then, at the last minute, they agreed to hold a site inspection. So the protest group has won a temporary reprieve.

No wonder the farmers are enraged by the thought that the labour of generations will be brought to nothing, that they will lose their land by compulsory purchase, and that several small family businesses will go under.

What annoys them most is that decisions are being taken by distant quangos whose members are totally ignorant of the area.

"The Government keeps talking about freedom of choice," said Mr Waters, "and yet we have none. Instead, we have to listen to a lot of twaddle from people who don't know the first thing about our environment, our heritage, our businesses, our traditions - and from people who don't care, either."