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Camelford case study

Updated Thursday, 19th September 2013
How did clear thought help during the water contamination disaster at Camelford?

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What happens when 20 tons of aluminium sulphate is accidentally poured into a water treatment plant?

A mistake in July 1988 saw 20 tonnes of aluminium sulphate added to drinking water in Camelford, Cornwall.

Discovering the cause of the incident, and reacting, called for clear thinking; it's a strong example of how systems thinking can rise to the occasion in a crisis.




News report

The prosecution has opened in the Camelford trial.  South West Water is accused of polluting Camelford’s water supply two years ago and poisoning a number of people: twenty tonnes of aluminium sulphate were accidentally poured into a water treatment plant; the Authority is denying the charges.

The jury were told they would hear a story of bundling and incompetence, of how the South West Water Authority failed to follow its own procedures.  Francis Gilbert QC listed a series of alleged failures, all or most of which he said were later admitted by the Water Authority Chairman.


Court battles with South West Water and a series of inquiries have thrown the unassuming town of Camelford into the public eye.  It started with an accident in a water treatment works.  Accidents will happen, but to some of the residents this was an accident that would not go away.

Lower Moor Work started life as a fully manned water treatment station.  It was later converted to operate automatically for much of the time unsupervised.  The incoming water is rather acid, so lime is added to neutralise it.  Aluminium sulphate is then added to remove the brown colour and bacteria at an early stage, and filtered out again before the water gets anywhere near the mains.  It’s a common enough chemical, and used routinely by waterworks all over the country for this purpose.  More of the alkali lime is pumped in to bring the final pH back to normal.

On July 6th 1988, the low pH alarm would not stop ringing.  Twice that day an engineer had to be called in to deal with problems.  First with the pre lime pump, and then the post lime vent, both had become blocked.  There was an attempt to bring the backup pump into action, but this too was defective.  That same day at an Avonmouth industrial estate, a road tanker was being filled with a solution of aluminium sulphate.

It was to be a relief driver at the wheel.  He’d never visited Lower Moor Works before, and the plant would be unattended when he arrived.  He was carrying a key passed to him by the regular driver, who in turn had acquired it unofficially for use when the treatment plant was unmanned.  The relief driver entered the works and looked for the storage tank.

Unfortunately the key fitted both the mains water tank and the storage tank.  The driver got the wrong one and poured twenty tonnes of aluminium sulphate directly into the water tank.  The entire slug of acid solution flowed into the supply network and there was nothing to warn the engineers that 30,000 gallons of dilute acid and aluminium were on their way to the public.

The plant design at Lower Moor meant that there was no way of monitoring the situation: all the sensors were upstream of the final holding tank.  The water was so acid it stripped copper from the inside of hot water tanks and dissolved lead out of lead pipes and solder, forming a toxic cocktail.  And the people were the first to notice.

Paul Hilliard, witness

This was the…

Female witness

This was the water taken at the time we discovered it.

Paul Hilliard

This was the first, you know, the sample that we ever took really, this was when we first became aware of it.  Which is quite obviously really, you know, they didn’t need anybody to tell you really what’s wrong with it, but.


Within hours of the accident, the Water Authority realised that the water was too acid.  They deduced, incorrectly, that this was due to the problems with the lime pumps.  They made the appropriate response, which was to dilute the acidity by flushing out the distribution system.  This operation forced 300,000 gallons of contaminated water out into the CamelRiver, killing thousands of fish.  Local GP Dr Richard Newman remembers it well.

Dr Richard Newman

The first thing I was aware of was driving up through Camelford at four o’clock in the morning and finding all the stop cocks turned on and water flowing down the main street.  That day and the next, we began to get numbers of people coming in with mouth ulcers, diarrhoea and vomiting, skin rashes and conjunctivitis that we hadn’t expected.







Unexpected effects were cropping up all over Camelford.  Diana King’s hair turned bright green when she washed it two days after the incident.  But the Water Authority said nothing.

Soon after the accident, staff at Lower Moor discovered that the level in the aluminium tank was low.  They rang their suppliers to check on what they thought was a missing consignment.  It was then that engineers realised what had happened.  But the public were ‘reassured’.  This notice, placed by South West Water in the sports pages of the local paper compared the effects of aluminium sulphate to those of lemon juice.

An inside tipoff from South West Water to the Western Morning News told a different story.  An article was published accusing the Water Authority of covering up by representing the accident as a minor plant breakdown and not the major contamination incident that it was.  The extent of that contamination was perhaps best known to the engineers.  It would take them many months to purge the mains of pockets of contaminants and clear away the aluminium and other minerals that over the years had encrusted the insides of pipes.

Their managers were also having to clear things up.  Under increasing pressure from the community, they set up a public inquiry and commissioned an independent internal investigation.  The resulting report was released at a press conference.

(15th August 1988)

Dr John Lawrence

Early on the morning of 6th July, there was a blockage in the pre-lime pump, that’s number one...


The author was Dr John Lawrence, an ICI scientist and non-executive member of the Authority.  He was critical of the Authority, but evidently not critical enough for science writer Elizabeth Sigmund, who had contributed to his inquiry.

Elizabeth Sigmund

When you say that aluminium sulphate is not harmful to people, have you read the reports of what it does to dialysis patients?  They call it dialysis dementia.  We know that it damages kidneys.

Dr John Lawrence

Um, I think…

Elizabeth Sigmund

I haven’t finished, Dr Lawrence.  I’m trying to speak for the people who have no voice yet in this inquiry.  We know that it damages people’s stomachs; we know that it damages arthritic patients quite severely.  This is all corroborated by scientists who know a lot about it.  And the Norwegians have recommended that no aluminium sulphate should be allowed in the water, because they have done a lot of studies which ally this substance with Alzheimer’s disease.  The whole thing is a disgrace!  It’s a disgrace to you gentlemen sitting here and it’s a disgrace to the medical profession, and I think that heads should roll.  And I think that it is the people who have drunk this stuff and of whom yet there’s been no survey except by local people, who should make sure that heads do roll, because they're the people that you're feeding with this stuff.


Later on the same day, those local people were to get a chance to confront the heads of South West Water for themselves.  Determined to find out what had been going on, they crowded into a public meeting, where Dr Lawrence was to present his findings a second time.

Dr John Lawrence

I am critical that no manager took, no clear manager took charge of this system and there is undoubtedly in the Authority, perhaps in the water industry more generally, a culture of don’t tell everybody, let’s get it right and let the public trust us to get it right.  I'm not defending that, but that undoubtedly was one of the factors involved, and it’s something that’s got to be changed.


He said that management was to blame.  The most senior member of management,
Authority Chairman Keith Court
, was next to speak.

Keith Court

I regret that you have to be here tonight.  It’s a report of censure.  There’s been a sequence of errors, omissions and underestimation, and none of it is excusable.  You’ve written to me, some of you have phoned me, you're annoyed and angry.  I understand and I would be doing the same thing if I was in your situation...


But apologetic remorse was not enough for an unhappy and unforgiving audience.

Dr John Lawrence

The lady over there hasn’t had a chance.

Female speaker

I'm an arthritic sufferer, which is bad.  I find that this, since this pollution, I've been far, far worse.  I can show the committee my hands, which I've had a terrible flare-up, and I was never like it until this water pollution.








Male speaker

I'd just like to pass up to the table, the top table, a sample of the water taken from my tap on Friday this week.  When we say everything is going to be done, have a look at that!

Female speaker

Drink it.

Male speaker

You wouldn’t drink it, you wouldn’t wash in it.  I know it does.  I've got an animal at home and a wife.

Male speaker

Drink the lot.

Keith Court

I wouldn’t like to drink it.

I can't accept responsibility for somebody else’s job and the competence which he brings to that job.


Why not?

Keith Court

Well we all have to rely on one another, don’t we?  We do it on the basis of trust.  What I have to do is to ensure that there are checks and verification procedures in the system, and what I have to say to that is that in the process of my combing through the organisation, I hadn’t got to Lower Moor to establish that particular verification procedure.


But come on, a senior civil servant or a minister or a commanding officer, in accepting responsibility for the institution over which he has control would be almost obliged to resign in circumstances such as these.

Keith Court

Well, I've been in the industry a long time, and I've observed the missions and failures, and we’d be in a pretty hopeless state if every time there was some incompetence down the line everybody at the top had to resign.  It does have to be, the scale of the thing has to be taken into account.

25th August 1988


The Health Ministry in London had been asked about the possibility of chemical poisoning at Camelford.  Its reply expressed doubt that anyone would have consumed much of the water, and if they had, the Department’s opinion was that it would do no more harm than if they'd eaten two slices of American cheese or swallowed their toothpaste while brushing their teeth.

Winter 1988

The Water Authority appointed a full time officer to run what it called a recovery programme.  It announced a health survey, increased monitoring points and a 10% cut in water rates, but the Camelford story had now become a national issue.

News report

Well Brigitte Pentecost is one of those who drank the contaminated water last July and she’s suffered ill health ever since.  I asked her earlier on Breakfast Time for her reaction to the water authority’s offer of a 10% rebate on her water rates.

Brigitte Pentecost

If you’ve been poisoned, you haven’t been tested and you’ve got no answers, and you’ve got the added worry about long term health problems, and you're still covering up going on, what would anybody’s reaction to be, what’s 10%, what’s money, I just want my health.


While the residents were fighting it out with the recovery programme, South West Water were considering suing their suppliers, but they themselves were facing prosecution, with a major police investigation already underway.

(One year later)

One year on, it seemed that the accident had poisoned the local economy as well as its people.  In the summer months, tourism is the lifeblood of this part of Cornwall, where thousands of visitors bring seasonal income and employment.  The contamination was long gone but the tourists hadn’t come back.









Two hundred miles away at Westminster, local Tories pressed Roger Freeman, one of the health ministers, for an inquiry.  Eventually Professor Dame Barbara Clayton, who’d previously served on government environmental committees, was asked to investigate.  In July 1989, the Clayton Report finally emerged.  The report confirmed the Ministry’s original advice that there would be no long term health problems.  The panel members put persistent illness down to psychological factors.

Professor Dame Barbara Clayton

It’s not possible to attribute the very real current health effects, which some people are still suffering, to the toxic effects of the incident, except in so far as they are the consequence of the sustained anxiety which has been felt, quite naturally, by so many people…

We are quite definite that we don’t anticipate long term effects, except in so far as there is a deep anxiety in the community, a very deep anxiety, and I think that’s very understandable.  In the reports we had, on the way that population was given information or lack of information, or erroneous information, right at the beginning from the Water Authority, I think that began a great period of anxiety.  And anger and anxiety are still present in that community.


People in that community are quite anxious that you only spoke to a very small number of people there and for a very brief period.  I mean they feel this probably wasn’t enough.

Professor Dame Barbara Clayton

Well, we spoke to some of the people.  We heard about families and friends.  We spoke to a lot of GPs, we had Dr Rowlands, and we had a great deal of information.  We’re very satisfied with the information that we were able to obtain.  Some of it took longer to obtain than others, but we did receive all that we needed.


Several GPs in the area of course are not quite so happy with what they see as long term symptoms in some of their patients, and they feel that anxiety is not a sufficient explanation.

Professor Dame Barbara Clayton

Well, you’ve had a panel of four experienced people with different skills, both medical and scientific, and we have given our report after a very thorough study, and our conclusion is that we are not expecting long term effects.  I think there are three things you have to recall.  One is that there was deep anxiety from the beginning, and anger.  Secondly that when you get an incident like this, people who are already ill or become ill tend to latch onto an incident.  It’s very common, we all do it, with much less severe incidents than this, we try to find a reason.

Dr Richard Newman GP

I don’t think I've ever seen anxiety causing arthritis, and I do think after twenty years plus in general practice, I could distinguish between an anxiety problem and a physical one.

Professor Dame Barbara Clayton

Well, everybody’s entitled to their opinion, but this is the view of the group, which included one of the world’s experts on aluminium, one of the outstanding epidemiologists, a very senior member in relation to water quality, and myself, and we have given you our report.







Even as the Clayton Committee was still deliberating, research was being carried out at EdinburghUniversity, which pointed to biochemical changes in the brains of young mice when their mothers had drunk water containing aluminium at lower levels than those initially found in Camelford.  Although the link with humans was still unproven, this was just part of the growing and sometimes contradictory body of scientific evidence.

(Winter 1990)

It’s rare for a government department to reopen a case, but as new studies came to light and controversy still raged, Junior Health Minister Stephen Dorrell asked the Clayton Committee to think again.

Stephen Dorrell, Junior Health Minister

There has been some concern that not all the scientific questions have been answered, arising from Lower Moor, and so it seemed to be sensible to call together the once again very high quality scientific advice that we had, and to ask them to look again at any new evidence that has arisen since they completed their work, and they’ve kindly agreed to do that.


In London, the decision had been made and the policy had been changed.  But in Camelford, many people didn’t share the minister’s confidence in the Clayton Committee.

Ivan Skudder

I personally have got short term memory problems, I've got rheumatism which I didn’t have prior to coming to Camelford, I've got an upset stomach and I've got eczema, all of which have happened since we've had this water pollution.  Now I don’t think it’s good enough.  They're telling us in the report that it’s short-term; I would love to know what short term is.

Doreen Skudder

Now I've just heard that it’s pretty well the same rehash of the original Clayton Committee with Dame Barbara in charge, and I'm extremely disappointed.  And so I can only hope that they will attack this with a more positive approach and really try to find out what is going on.

(January 1991)

BBC News report


South West Water Authority has been found guilty of supplying polluted water to 20,000 people in the Camelford area of North Cornwall in 1988.  Supplies were contaminated when a lorry driver accidentally tipped aluminium sulphate into a treatment works.  The Authority was fined £10,000 with £25,000 costs.  It plans to appeal.


Those supporting the victims of the incident were delighted by a guilty verdict, which they say vindicates their campaign for a full public inquiry and compensation.

Female speaker

Now they know that we can go ahead and fight, both for medical treatment for them which they’ve never had, and also for compensation for loss of their lives, their work and their children’s health, which worries me more than anything.


In court, the judge said the penalty he’d imposed was modest, because many of the allegations against the Authority had in his words been demolished.  The judge also noted that as it was the old authority, a public body that had been taken to court, all the costs of the case including the fine would have to be met by the taxpayer.

And the costs are not over yet.  At a news conference, lawyers for the Water Authority said they will appeal against the conviction and eventually the Department of the Environment will have to pick up the bill from public funds.


South West Water Authority could now face more than 600 civil actions, brought by people who say their health was affected because of the incident.


Spring 1993

175 people are suing South West Water

The Skudders exhausted their resources before their case even came to court.

At first they were offered £300 each.  This was increased to £500 after brain damage was demonstrated.

So far South West Water has paid less than £100,000 out of court.

Those claimants who received payment got sums ranging from £10 to £2,000.



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