Protecting UK’s water supplies

Michael J Scott from SWIG takes an in-depth look at how prepared Britain is for dealing with water contamination emergencies and at how water compliance in the UK is a top priority


Provision of safe drinking water is a prime goal for water companies. Prescribed testing programmes have consistently shown drinking water in the UK to be both potable and safe – the Drinking Water Inspectorate’s (DWI) most recent report shows 99.88% compliance. This is testament to the intuition and persistence of Victorian public health engineers, as well as the rigorously enforced testing regimes and the sound operational practices and investment programmes of modern water companies.

However, as analytical capabilities, health awareness and consumer perceptions have advanced over the years, there has been pressure for even more scrutiny of this basic commodity for life. Water supply involves a series of interlinked operations and activities such as identifying raw water sources, establishing appropriate treatment, ensuring continuously effective treatment, pumping, storage and distribution of the potable water. In a similar way, treatment of water consists of multi-stages, without reliance being placed upon a single process.

The protection of the supply systems is likewise multi-layered. The source is protected so as to reduce the need for treatment. The treatment is protected so as to reduce the need for short term ’emergency’ intervention. The potable water in the distribution system is protected so as to protect the consumer. The water supply industry is not immune to wilful tampering by terrorist or other illegal activities and this has forced a wide range of professional bodies to consider what threats might exist and how they are to be dealt with.

Water supply is, inherently, a sealed system from treatment works to the customer tap and it is very difficult, but not impossible, to gain access. From catchment to customer, the protection of water supplies is a multi-faceted operation employing many ‘barriers’, controls and checks to unwanted substances. At the primary health level, chlorine residual is typically maintained throughout the distribution system and new technology is being developed to monitor and maintain levels right to the customer’s tap.

Many unwanted chemical compounds are detected by taste and odour signs before reaching harmful health concentrations. Dilution factors are inherently so large that harmful concentrations by wilful illegal activities are difficult to achieve. A final protective tier, independent of the water suppliers is provided by public health doctors and environmental health officials. They act as regulatory watchdogs on health matters on behalf of consumers and can rapidly access health risk databases to facilitate decision-making during emergencies. Suitable formal communication channels are maintained by water companies.

On a worldwide basis, water contamination emergencies have been rare and are becoming rarer. The successful International Water Contamination Emergencies Conference, held in Kenilworth in June 2003 and sponsored by the Institution of Water Officers, Royal Society of Chemistry and Society of Chemical Industry, showed the water industry is well prepared to cope with water contamination emergencies, but incidents have occurred where the water quality has been impaired and significant cost and inconvenience incurred.

Public health has been potentially at risk and sometimes public perception has been of a more serious problem than was usually the case. However, there is no room for complacency and some people believe there would be benefits in a raised state of awareness and a broad ranging review so as to reassure consumers the existing robust ‘barriers’ can be effective for chemical and bioterrorism and nuclear threats.

The conference in 2003 concluded there was a need for more proactive collaboration, for example, DWI, Health Protection Agency, local authorities, international agencies, academia, should all feature in any up-to-date re-assessment. A follow-up conference in June 2005 at the Manchester Conference Centre is set to explore the collective capability within the water industry and its ability to co-operate with other bodies and to draw on the external expertise, which is readily available. There is a firmly held belief water for industrial/commercial use is delivered effortlessly in constant quality terms and security is ensured because it is delivered in underground pipes.

However, since the water companies collect the raw material and distribute the finished product, they must individually and severally ensure their corporate governance includes planning for a water supply/quality emergency:

  • have contingencies in place to allow for extremes such as product recall,
  • can identify appropriate points in production processes where water quality is critical,
  • have identified contractors to provide critical supplies should the need arise,
  • have robust PR management plans in place to deal with customer queries relative to a water quality issue affecting production.
  • Although the bullet points are easily generated, they each raise a host of issues. For example, any one company may well have excellent plans in place but there is some doubt as to whether the plans have been sufficiently tested or indeed are well-known across all departments in the company. The necessary sharing of these plans between water companies is probably limited to high-level agreements and there appears to be room for more pro-active sharing of these plans with such bodies as the police and local authorities.

    There seems to be room for discussion and at least outline agreement about where liabilities rest with respect to water quality and the use of mains water once it enters industrial or commercial premises. All responsible companies and individuals have insurance but insurance, even if it is of the type applicable to a water quality emergency, only provides financial recompense – it does not deliver immediate management solutions and brand protection in the first few hours of a crisis.

    How do you know you have a problem? A problem or emergency only exists when it has been recognised. A key step in guarding drinking water quality is monitoring and, principally, laboratory testing. Samples from a potential pollution or deliberate contamination incident rarely have the target identified. Thus the analyst is challenged to prove an unknown negative, which is far more difficult than targeted analysis. In 1995 the major UK water laboratories set-up a mutual aid scheme.

    The laboratories meet formally each year and discuss any significant emergency incidents. The following advantages arise from this:

  • companies learn from other companies’ incidents and the way they were handled,
  • companies admit mistakes made during incidents and thus help another company avoid the same mistake,
  • there is a capability statement with a 24h contact telephone number for all 18 laboratories. Thus laboratories that can offer specialised analysis services are quickly identified (for example, radioactivity, class-three pathogens; parasites; ecotoxicity testing facilities; high-resolution gas-chromatography mass spectrometry; high-pressure liquid chromatography mass spectrometry (HPLC-MS), etc),
  • sub-groups have set up useful rapid screening methods so laboratories can run large numbers of emergency samples to rapidly identify the ‘problem’ samples (inorganic; organic; ecotoxicity and radioactivity),
  • a gas-chromatography mass spectrometry screening method has been developed that can give results down to about 1ug/l in a 15min cycle time with rapid sample pre-treatment and derivatisation step,
  • screening methods are currently being devised
    for HPLC-MS techniques with direct injection of water samples,
  • a number of low-cost, simple rapid screening methods suitable for large numbers of samples have also been developed. These include TOC, chlorine demand, cyanide, paraquat/diquat, permanganate index (PI), cholinesterase inhibitors and diode array UV scanning.
  • All the planning, training, pro-active co-operation and real-life practices will come to nought if the general public disbelieve what they are being told, wilfully refuse to follow instructions or panic. A major issue is the communication between the many companies and official bodies that will be involved in small incidents. Even a minor potential incident can rapidly become an expensive or even dangerous issue if the wrong message is given or picked up by the media or misguided enthusiasts. Dilution factors are so great that major incidents are rare and the incidents are now little more than nuisances.

    Strangely enough this presents a serious problem to those involved because science and technology is more important in analysing the actual problem. We all know scientists and engineers are not good at communicating with a wide range of listeners – the listeners, including the PR people and those holding budget strings for responses are not that good at listening. So there is a need to establish strong ongoing links with good ‘translators’ between the various management levels, skills and interests that are involved in any ‘incident’. This is not a trivial undertaking. The follow-up conference (Water Contamination Emergencies – Enhancing Our Response) to the 2003 Conference programme considers the various elements to be addressed in protecting water supplies and therefore protecting consumers.

    Issues to be debated include: Impacts on public health and commerce, representative sampling, analysis, communication of risk, emergency planning and control, chemical, biological, radiological and nuclear (CBRN) issues and threats to the industry whether physical, based on chemical or microbiological agents or linked to IT. The aim of the conference is not just to make formal presentations to relevant professionals but to provide the forum in which a free and energetic exchange may take place to allow a greater understanding by all of the many organisations and professional bodies that are required to operate effectively on a 24/7 basis.

    Sponsors include: Institute of Water Officers (IWO), Royal Society of Chemistry (RSC), Society of Chemical Industry (SCI), Drinking Water Inspectorate (DWI), Scottish Water, Severn Trent Water, AWG and Yorkshire Water.

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