Gathering of the clams poised to overwhelm our waterways


It is smaller than a matchbox and as big as a potato crisp, but the tiny Asiatic clam can cripple power stations, close factories and poison the water supply - and now it's here.

It is smaller than a matchbox and as big as a potato crisp, but the tiny Asiatic clam can cripple power stations, close factories and poison the water supply - and now it's here.

Scientists have discovered that millions of the 11/2in molluscs are silently massing in East Anglia, poised to wreak havoc across Britain's inland waterways.

The clam's small size and prolific breeding enable it to infiltrate and clog the pipes and condensing systems of industries that use rivers for cooling purposes. Power stations - including nuclear ones - are particularly vulnerable.

For the time being, the Asiatic clam, Corbicula fluminea, is restricted to the Norfolk Broads. But there are fears that unless it is contained it will emulate the damage it has caused in the United States, where the clear-up operation is a multi-million-dollar industry.

They also pose a serious health risk as tons of rotting clam flesh could poison the domestic water system.

"It is only a matter of time before it spreads," said Dr Roy Baker, a retired zoologist who first identified the Asiatic clam's presence in Britain. "We can't do anything about it. The potential is there for it to be a real problem. The only thing you can do is control it by chlorinating the water."

The clam, native to the South China Sea, is a bivalve first identified in the Norfolk Broads two years ago. Then they amounted to no more than a handful but today the population is thought to be several million - and growing.

The Asiatic clam is moving forward on two flanks. Like all cockles and mussels it uses its fleshy "foot" to pull itself through the silt. At the same time the clam releases free-standing larvae that float in the water and are carried along by the tide. It has already spread from the southern Broads around the Rivers Waveney and Yare to the River Thurne 25 miles away. It could soon enter the main water pipe supplying water from the region to London and Essex and young clams and larvae will soon find their way into the condensers of power stations.

It also threatens to displace native species such as the depressed river mussel. The Environment Agency is concerned because the clam is aggressive and takes up space on the sea bed needed by the depressed river mussel, which is highly endangered, while the Norfolk Wildlife Trust has found that the population of Asiatic clams on the River Chet has created a layer on the riverbed which stops other flora from flourishing.

Julia Stansfield, a biologist with the Environment Agency, likened the clam's impact to that of the grey squirrel on red squirrels. She said: "One solution is to poison the river bed to kill off the clams but that would wipe out the depressed river mussel as well. There is no action we can take to get rid of it that isn't drastic."

The Asiatic clam is thought to have been introduced to Britain by the trade in exotic fish, in particular koi carp. The water in which the carp are imported often contains the clams and their larvae which are simply dropped into the water system along with the fish.

Its advance through Norfolk's waterways has been helped by holidaymakers on barges. The clam attaches itself to the weights the boats use and is found in great concentrations near riverside pubs.

It was first identified in the US in 1957 and spread at a phenomenal rate: 10 years later it knocked out a nuclear power plant in Russelville, Arkansas.

Jacqueline Bisset has claimed that young women today are obsessed with being 'hot', rather than 'charming', 'romantic' or 'beautiful'
Arts and Entertainment
Lena Dunham
booksLena Dunham's memoirs - written at the age of 28 - are honest to the point of making you squirm
Arts and Entertainment
A bit rich: Maggie Smith in Downton Abbey
tvDownton Abbey review: It's six months since we last caught up with the Crawley clan
Frank Lampard and his non-celebration
premier leagueManchester City vs Chelsea match report from the Etihad Stadium
Have you tried new the Independent Digital Edition apps?
Life and Style
A new app has been launched that enables people to have a cuddle from a stranger
techNew app offers 'PG alternative' to dating services like Tinder
Greg Dyke insists he will not resign as Football Association chairman after receiving a watch worth more than £16,000 but has called for an end to the culture of gifts being given to football officials
Arts and Entertainment
Jake Quickenden sings his heart out in his second audition
tvX Factor: How did the Jakes - and Charlie Martinez - fare?
premier league
Arts and Entertainment
'New Tricks' star Dennis Waterman is departing from the show after he completes filming on two more episodes
tvOnly remaining original cast-member to leave crime series
Mario Balotelli celebrates his first Liverpool goal
premier leagueLiverpool striker expressed his opinion about the 5-3 thriller with Leicester - then this happened
Britain's shadow chancellor Ed Balls (L) challenges reporter Rob Merrick for the ball during the Labour Party versus the media soccer match,
peopleReporter left bleeding after tackle from shadow Chancellor in annual political football match
Arts and Entertainment
Female fans want more explicit male sex in Game of Thrones, George R R Martin says
tvSpoiler warning: Star of George RR Martin's hit series says viewers have 'not seen the last' of him/her
Plenty to ponder: Amir Khan has had repeated problems with US immigration because of his Muslim faith and now American television may shun him
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
iJobs Job Widget
iJobs General

IT Support Technician (2nd Line / Server Support) - Bedford

£24000 - £26000 per annum + Benefits: Ashdown Group: 2nd line IT Support Techn...


£100 - £130 per day: Randstad Education Chelmsford: Would you like to have a b...

Year 3 Teacher

£100 - £130 per day: Randstad Education Chelmsford: KS2 TeacherWould you like ...

Science Teacher

£100 - £140 per day: Randstad Education Preston: Are you a qualified science t...

Day In a Page

A roller-coaster tale from the 'voice of a generation'

Not That Kind of Girl:

A roller-coaster tale from 'voice of a generation' Lena Dunham
London is not bedlam or a cradle of vice. In fact it, as much as anywhere, deserves independence

London is not bedlam or a cradle of vice

In fact it, as much as anywhere, deserves independence
Vivienne Westwood 'didn’t want' relationship with Malcolm McLaren

Vivienne Westwood 'didn’t want' relationship with McLaren

Designer 'felt pressured' into going out with Sex Pistols manager
Jourdan Dunn: Model mother

Model mother

Jordan Dunn became one of the best-paid models in the world
Apple still coolest brand – despite U2 PR disaster

Apple still the coolest brand

Despite PR disaster of free U2 album
Scottish referendum: The Yes vote was the love that dared speak its name, but it was not to be

Despite the result, this is the end of the status quo

Boyd Tonkin on the fall-out from the Scottish referendum
Manolo Blahnik: The high priest of heels talks flats, Englishness, and why he loves Mary Beard

Manolo Blahnik: Flats, Englishness, and Mary Beard

The shoe designer who has been dubbed 'the patron saint of the stiletto'
The Beatles biographer reveals exclusive original manuscripts of some of the best pop songs ever written

Scrambled eggs and LSD

Behind The Beatles' lyrics - thanks to Hunter Davis's original manuscript copies
'Normcore' fashion: Blending in is the new standing out in latest catwalk non-trend

'Normcore': Blending in is the new standing out

Just when fashion was in grave danger of running out of trends, it only went and invented the non-trend. Rebecca Gonsalves investigates
Dance’s new leading ladies fight back: How female vocalists are now writing their own hits

New leading ladies of dance fight back

How female vocalists are now writing their own hits
Mystery of the Ground Zero wedding photo

A shot in the dark

Mystery of the wedding photo from Ground Zero
His life, the universe and everything

His life, the universe and everything

New biography sheds light on comic genius of Douglas Adams
Save us from small screen superheroes

Save us from small screen superheroes

Shows like Agents of S.H.I.E.L.D are little more than marketing tools
Reach for the skies

Reach for the skies

From pools to football pitches, rooftop living is looking up
These are the 12 best hotel spas in the UK

12 best hotel spas in the UK

Some hotels go all out on facilities; others stand out for the sheer quality of treatments