Haunting BBC Pollution Film: Poison Water

On July 6th 1988, a relief tanker driver for the South West Water Authority discharged 20 tonnes of aluminium sulphate solution into the wrong tank at the unmanned water treatment works at Lowermoor, near Camelford in Cornwall. Consequently, water supplies serving a large area of North Cornwall were contaminated. 

Aluminium sulphate solution is routinely used as a coagulant and flocculant in potable water treatment, added early in the process to coagulate suspended solid matter and facilitate removal by sedimentation and filtration, as well as removing the majority of aluminium ions as hydroxide. 

In this instance, however, the solution was discharged into the chlorine contact tank instead of into a storage tank. The chlorine tank was located immediately upstream of the treated water reservoir for water waiting to be distributed through the mains.  

Contaminated water moved into the treated water reservoir and then into the distribution system. Defra was notified that all the aluminium from the mistaken delivery had entered the public system within two days of the incident taking place. 

In the evening of July 6th, customer complaints began to come in that water had a sticky feel to the touch and an unpleasant taste, consistent with water of low pH and the presence of aluminium sulphate. Initially, this was incorrectly put down to issues with the lime treatment plant. 

Later that night, the water authority began to flush out the acid water from the distribution pies, emptying it into rivers and waterways. The primary flush was made in the River Camel, upstream of Camelford, while the secondary flush was made into the River Allen. 

This meant that a lot of the aluminium sulphate in the chlorine contact tank and treated water reservoir was drawn into the distribution system and local waterways, leading to fish fatalities in both rivers before the full extent of the problem was recognised. 

The toxicity of the water was further increased because the higher acidity levels stripped lead and copper from the pipes. 

On the morning of July 8th, it was noticed that the aluminium levels in the correct storage tank were low, at which point the misdelivery and contamination source were discovered.

The area covered by the Lowermoor distribution system included around 7,000 properties, with estimations indicating that the local summer population was around 20,000 people, approximately 12,000 of whom were residents.

Residents in Camelford began experiencing issues such as sore throats, joint pain, bowel problems, vomiting and short-term memory loss… yet the water authority advised members of the public that the water was still safe to drink. 

Studies show that aluminium is a well-established neurotoxin and accidental contamination of Camelford drinking water supplies led to symptoms such as loss of concentration and short-term memory that were originally attributed to anxiety. 

Psychomotor performance was found to be poorer than predicted among those residents exposed to contaminated supplies and aluminium sulphate poisoning probably resulted in long-term cerebral impairment in some people. 

A report published in 2013 by the Lowermoor subgroup of the Committee on Toxicity of Chemicals in Food, Consumer Products and the Environment found that exposure to the chemicals wasn’t likely to cause delayed or persistent harm.

However, it also concluded that further research was needed, including on the effect of contaminants on neurological health – important given that there is already a link between aluminium and dementia.

The BBC film covers what is now known as Britain’s biggest mass poisoning event, leading to decades of searching for the truth, human suffering and accusations of a cover-up. 

At the time of the incident, which coincided with the privatisation of the water industry, speculation grew that the truth about what happened was deliberately withheld from the public. 

For example, a leaked government memo indicated that South West Water executives were worried that a police investigation into the case could potentially spook the stock market and affect the sale price of the company. 

Fast forward 37 years and water companies are back in the news time and time again, with pollution scandal after pollution scandal hitting the headlines… so what lessons, if any, have actually been learned? 

This new film covering what happened features archive footage and personal accounts, as well as locals who were badly affected by the incident, scientific interviews, the head of operations at the South West Water Authority, and Michael Howard – the minister responsible for water industry privatisation. 

Reviewing the dramatisation and giving it five stars, the Guardian described it as “a damning tale of greed [and] incompetence”, adding: 

“There is a risk that the final product could feel more like a repackaging [of a previous BBC horizon episode] than an original piece.  

“Naturally, though, taking a four-decade step back from events casts them in a different light. And there are enough new interviews here – with residents, experts and politicians – to bring the whole thing startlingly, discomfitingly into the present.” 

The Financial Times, meanwhile, wrote: “It does a tremendous job of unravelling events and determining what actually happened, as well as exposing the staggering levels of cover-up that meant that, for years, the truth about it was kept from the public … As a documentary, this is gripping and full of character. It is also timely.”

Although the Camelford incident took place nearly 40 years ago, water pollution is as big an issue now than ever – if not more so. 

If, as a business, you’re keen to improve your own water management practices and become part of the solution rather than part of the problem, get in touch with the H2o Building Services team to find out what we can achieve together.