Pollution from watercress farm casts a shadow over fly-fishing's classic river

Europe's biggest watercress farm is seeking to expand along one of England's most beloved small rivers, whose waters it has already badly polluted.

Europe's biggest watercress farm is seeking to expand along one of England's most beloved small rivers, whose waters it has already badly polluted.

Vitacress Salads wants to increase production at its plant on the Bourne rivulet in Hampshire, a miniature chalk stream less than three miles long, which despite its size has become a place of pilgrimage for fly-fishermen from around the world.

The Bourne, a crystal-clear tributary of the river Test, was made famous by a fishing-mad classical singer, Harry PlunketGreene, who lived in the valley from 1902 to 1912. His account of his happy years by the Bourne, Where The Bright Waters Meet, published in 1924, is regarded as a classic of angling literature, and fishermen from many countries come to the valley to fish the river and pay homage to Plunket Greene's memory.

However, according to a report from the Environment Agency, the ultra-pure waters that Plunket Greene knew have been seriously degraded by effluent from the watercress farm at the village of St Mary Bourne.

It is a sizeable industrial plant, which Vitacress says produced more than one million bags of salad per week last year, mainly to supply supermarkets. The company is now seeking planning permission for eight new cress beds.

Yet the operation, the Environment Agency says, is damaging the river. "It is clear that St Mary Bourne cress farm is causing a significant decline in the ecology of the Bourne rivulet," the report says. "The macro invertebrate communities [creatures such as insects and shrimps] have changed in response to pollutants of a toxic nature and to increased siltation of the stream." The report may come as a shock to anyone who thinks of watercress as symbolising all that is simple, clean and healthy. It spells out the downstream harm caused by various chemicals used on the Vitacress farm, including pesticides, chlorine and zinc.

The detrimental effects of pesticides and chlorine may be seen in the disappearance of pollution-sensitive caddis flies and a reduction in mayflies, the report says.

Silt produced by the farm has killed aquatic insects such as riffle beetles, while zinc, used to control an infection of cress farms called crook root disease, is having a "profound" effect on the common freshwater shrimp, Gammarus pulex.

The shrimps, normally super-abundant, are the main food for the Bourne's trout, and the reason – to Plunket Greene's delight as an angler 100 years ago – the fish of such a small stream grow so fat. Nothing can better illustrate the effect of the Vitacress plant than to look at the narrow branch of the river where, on 29 August 1904, the singer-fisherman caught three large trout without moving from the same spot (and never ceased talking about it).

This branch is now the main effluent channel from the cress farm and is virtually dead. Freshwater shrimps are absent, the agency report says, while in the neighbouring branch of the river a few yards away a recent survey showed them present in thousands in a small area.

After the two branches join, the life of the river is badly affected for much of its length.

Last week, William Daniel, a fishing guide who takes people on Plunket Greene pilgrimages along the Bourne, demonstrated the continuing truth of this: stirring the river-bed gravel and netting the water, he produced a net full of shrimps and other tiny creatures from one branch of the Bourne, and a net from the other with no life in it at all.

"This is one of the world's most important chalk streams in an area of outstanding natural beauty, and the way it is being damaged by the largest cress and salad operation in Europe is nothing short of scandalous," Mr Daniel said.

"Any increase in its size will have a further adverse effect on the wildlife and I will strongly object to it." The Environment Agency would also be objecting, said Shirley Medgett, the agency biologist who wrote the report on the Bourne in 1998 and continues to monitor the health of river.

The report's conclusions were valid today, she said. "Any increase in production is likely to cause further detriment to the river and we would be likely to object on those grounds," she said.

The very visible damage to such a small and beautiful watercourse produces haunting echoes ofThe Stream, the novel by Brian Clarke about the death of a chalk stream from pollution, development and intensive farming, which won two important literary prizes last year.

Mr Clarke knows the Bourne himself and said he was appalled at what was happening to it.

"This is a living example of the stream in my novel," he said. "What I tried to show was how, little by little, we may unwittingly be causing changes to the environment on which our own lives ultimately depend.

"But if I'd used a stream treated with the deliberate callousness of this piece of the Bourne, I'd have been accused of wild exaggeration.

"An expansion of this farm is absolutely the last thing we need. What is needed is an urgent brake on its activities until the cause of the problems can be identified and resolved," Mr Clarke said.

No one from Vitacress management was available for comment last week.

The Independent was referred to Rick Sturdy, a landscape architect and agent for the company's planning application. His wife, Ayda Sturdy, said: "We are landscape architects. We don't know anything about pollution."