Marine life put at risk by plans to dredge the Channel's seabed

It's size beggars belief. A section of the English Channel's seabed, it extends for nearly 400 square miles, about half the size of Luxembourg – and it is likely to become a gigantic quarry.

It's size beggars belief. A section of the English Channel's seabed, it extends for nearly 400 square miles, about half the size of Luxembourg – and it is likely to become a gigantic quarry.

If a group of six British companies has its way, dredgers will extract hundreds of millions of tons of sand and gravel contained from the area 30 miles offshore, between the Sussex coast and the Pas-de-Calais. The intention is to satisfy the construction industry's insatiable hunger for building materials for years to come.

But the proposal for the super quarry is arousing concern among marine conservationists – and something approaching panic among French fishing communities, who say it is a vital fish spawning ground.

Although the dredging would be in British waters – the site is just on the British side of the UK-France "median line" – it would occupy an area rich in sea life, from scallops to whiting, sole and plaice, which is mostly fished by Dutch, Belgian and above all French boats, based along the northern coast, from Boulogne to Cherbourg.

Leaders of the French fishing industry have protested to the European Commission, claiming that sand and gravel extraction on such a scale would virtually "sterilise" a large part of the Channel. They want Brussels to investigate the impact on the already dwindling Channel fish stocks.

Yet the Commission and the French Government would have few rights to object to the plan if the British Government gives the go-ahead. Seabed mining and dredging is a national prerogative under maritime and EU law. The decision on whether the project will go ahead lies with the Department of Transport, Local Government and the Regions , and ultimately with its Secretary of State, Stephen Byers.

Behind the proposal is the UK construction industry's unceasing demand for aggregates – the sand, gravel and crushed rock used as raw materials in building everything from office blocks to motorways.

Demand for marine aggregates – those that can be taken from the seabed – has increased significantly in the past 30 years. The aggregates now account for a fifth of Britain's demand for sand and gravel as a whole, but a third of the demand in the South-east, and as much as half of the demand in London, where they have supplied most of the raw material for the group of skyscrapers being built at Canary Wharf in the east of the capital.

However, many of the 74 existing extraction licences, at sites all round the coast, are nearing the end of their commercial lives, and over several years the industry has mounted an intensive investigation for new sources.

The East Channel site, as it is known, is the result. Yet its unprecedented size – it is thought to contain 550 million tons of sand and gravel – has set alarm bells ringing among scientists concerned with sea life. "We are very concerned about the Eastern English Channel proposal," said Melissa Morton of the Marine Conservation Society. "If it is licensed it will result in the suction dredging of hundreds of millions of tons of the seabed and the associated marine species that live there.

"As well as direct impacts at the site, this proposal may affect the wider marine environment by stirring up sediment which may smother neighbouring habitats, and there is likely to be a knock-on effect up the food chain too, as the bottom-dwelling species and seaweeds which are removed represent a source of food for crustaceans and fish."

This last concern is at the heart of the French objections. "We are very, very worried," said Jean-Pierre Grandidier, the director of a fishing co-operative at Étaples, near Le Touquet, in the Pas-de-Calais. "This area is not only rich in mature fish, it is one of the main breeding grounds for all the species which make our livelihood: scallops, red mullet, cuttlefish, sole, plaice and whiting.

"If you extract hundreds of thousands of tons of gravel and sand from the seabed, you not only disturb the mature fish, you destroy the vegetation on which immature fish feed. As one of my members said, it would be like taking a metre of topsoil from one of the best vineyards in Bordeaux."

A private study of the environmental impact, commissioned by the six British companies, known together as the East Channel Association, is expected to be completed next month.

A French maritime expert commissioned to contribute to the study, Benoît Caillart, told The Independent yesterday that there was no doubt that the underwater quarry, if it went ahead, would "seriously damage" fish stocks. He estimates that the 300 French fishing boats operating in the eastern Channel would lose around half their earnings.

In its letter of protest to the European Commission, the French national fisheries committee says sand and gravel extraction on such a scale would "amount to an irreversible change in the environment, which could leave a large part of the Channel virtually sterile of all living resources".

The committee says it is absurd for the EU to claim to manage fisheries on the one hand – imposing tighter and tighter limits on catches and net sizes – while allowing fish stocks to be damaged beyond repair by off-shore, industrial activities.

The East Channel Association companies say they will take account of the worries. "We accept the concerns that are being raised, and they will be addressed as part of the environmental impact assessments that will be carried out," said their spokesman, Dr Andrew Bellamy of the company United Marine Dredging.

"The [Government] will not give permission to dredge unless they are satisfied that the proposal is environmentally acceptable, and concerns and wishes of stakeholders, including fishermen, are taken into account."

Dr Bellamy said that by no means the whole area would be dredged at one time. "For example, 90 per cent of the marine dredging that is currently going on is taking place in an area of just 12 square kilometres." And the seabed gradually recovered after dredging, he said. Recent research suggested recovery could take between three and five years.

There was a need for a continuing supply of marine sand and gravel, Dr Bellamy said, for "everything from houses, shops and hospitals to Canary Wharf".

Officials in Stephen Byers's department are studying the first three of 10 planning applications that the dredging companies are due to submit.

"The Government will not allow marine dredging operations to be undertaken unless it is satisfied there would be no adverse impact on the coast, and no unacceptable effect on marine habitats that cannot be mitigated," a spokesman for the department said.

But Ms Morton, of the Marine Conservation Society, said: "The Government claims that it is committed to sustainable development, yet given that this is a finite resource, this is clearly not sustainable.

"It appears to be assumed that because the site is offshore and hence out of sight and out of mind, the public will not be concerned about the habitat and species destruction caused," Ms Morton said.

"But the effect of this dredging in combination with overfishing, shipping and pollution could be significant for the Channel."

The species under threat

Cuttlefish

A relative of the squid, cuttlefish is hardly eaten in Britain but is a delicacy in some European countries. Its scientific name is Sepia officinalis; sepia is the name of the ink once used by artists.

Plaice

A bottom-dwelling flatfish found on sand at depths of up to 150ft, plaice are an important fish for European fisheries; Channel stocks are already depleted beyond safe biological limits.

Scallops

Scallops are found at depths down to 300ft, living on the sea bed, partially buried. Dredging for scallops itself damages the sea bed and bigger specimens are now usually caught by divers.

Sole

Another bottom-dwelling flatfish, sole in the Eastern Channel is being harvested outside safe biological limits, according to the International Council for the Exploitation of the Sea.

Whiting

Whiting are found all over the north-east Atlantic, but as an important commercial species they are very heavily fished and many stocks are already regarded as below safe biological limits.