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Water Contamination Emergencies
Can we Cope?
By K.C. Thompson, J. Gray The Royal Society of Chemistry
Copyright © 2004 The Royal Society of Chemistry
All rights reserved.
ISBN: 978-0-85404-658-4
CHAPTER 1
OPENING ADDRESS TO THE WATER CONTAMINATION EMERGENCIES: CAN WE COPE? INTERNATIONAL CONFERENCE, 17 MARCH 2003.
R. Anderson
Department for the Environment, Food and Rural Affairs, Ashdown House, 123 Victoria Street, London SWIE 6DE
1 INTRODUCTION
Looking through your agenda for the next three days and the list of delegates, I had two immediate thoughts. First, it is a real privilege to give this address. The range and depth of expertise represented here today is impressive. And, speaking personally, I must say pretty formidable. Second, the agenda and the range of expertise, brings home the complexity and numerous variety of challenges we face today.
I propose to offer a lay perspective – or, perhaps more accurately, a perspective based on a different kind of experience and responsibility. My concerns are the policies and the framework within which water supply and regulation operates in England. I hope, therefore, that you will see my presentation as contextual.
The title of this conference is Water Contamination Emergencies: Can We Cope? Our ability to cope will, in part, reflect the robustness of our day-to-day arrangements. The robustness of the basic structure for delivery of water services. And, in part, our ability to respond to the unexpected.
2 BASIC STRUCTURE
2.1 How are we doing on the basic structure?
For me, this starts with the standards to which water services are provided. We need to be confident about service levels, about monitoring arrangements, and about enforcement – where necessary. We also need to be realistic about the robustness the system to cope with potential risks.
2.2 Expectations are rightly high.
When I turn on the tap at home and fill my glass with water, I do so in the belief that it is safe to drink it. I make the same assumption here today. The consumer may not know the technical quality standard to which the water must adhere, but assumes that Government will have set out standards and processes that make it safe.
You will not need me to go into the detail of present UK standards for drinking water and for maintaining environmental quality. The key point is that they reflect current scientific advice and are, in almost all respects, common across the EU. The 1980 Drinking Water Directive introduced mandatory standards to protect public health and to ensure that water supplies were wholesome throughout the European Community. Those concerning the environment are set at a level which is proportionate to the risk of pollution posed, while being sufficiently stringent to ensure that there is no observable effect to sensitive aquatic ecosystems.
5 HORIZON SCANNING
It is not enough to rely on what we currently know, we must research and learn. And we must learn to listen. Our record in the UK in the past has not always been successful. We did not fully anticipate the threat from Cryptosporidium. BSE was equally unanticipated. In each case, I think there was a failure to scan the horizon and ask the right people the right questions.
We must engage with those at the fringes of the Department's activities, including those who might have conflicting objectives or opinions. Not just those at the heart of what we do. And not just those who agree with us. And this needs to be built into the research process.
With this in mind, my Department has now incorporated "Horizon Scanning" as a keystone of its science strategy. An open house invitation was extended to Individuals and organisations to comment on:
• Potential threats and opportunities, including socio-economic aspects;
• Vulnerabilities of sectors for which DEFRA has responsibility with a view to developing policies that reinforce resilience; and
• Novel or critical perspectives on current policies with a view to improving the robustness of the policy making process.
As a result, across the Department we are focussing on five priority themes:
• Future landscapes and the influence of land use and environmental planning;
• Environmental constraints and the impact of the reducing availability of natural resources;
• Re-thinking the food economy;
• Coping with threats – society's ability to adapt to environmental change and the impact of new diseases; and
• Meeting people's future needs.
These themes go much wider than water. But, by taking this broad interlocking approach, we seek to ensure that research on water issues is seen in a wider context.
4 RESEARCH EFFORTS
So, looking forward, where should we concentrate our research efforts? A substantial proportion of the drinking water research budget is likely to be devoted to characterising the possibility of risk amplification arising from the coincidence of different low frequency / low risk events. By way of example I will mention two areas.
One is storage of water for drinking within buildings. This might create conditions that favour the multiplication of bacterial species that would not normally present a risk via drinking water.
Another is low concentrations of disinfection by-products in water. Showering or swimming could give rise inhalation of volatile DBP and could present amplified risk at certain stages of pregnancy.
In the field of environmental water protection, the focus of current research is towards understanding and addressing challenges such as agricultural and urban diffuse pollution and climate change and towards underpinning the regulatory regimes relating, for instance, to dangerous substances.
As we learn more from the results of future research, the findings can be fed into future revisions of standards. As we saw with the way in which the Drinking Water Directive was revised in 1998 to take account of the updated World Health Organisation guidance on water quality parameters.
The new regulations introduce a number of new standards and more stringent values for some existing parameters. The most important change is for lead where the current standard for lead of 50 micrograms per litre is tightened to 25 micrograms per litre by the end of 2003 and 10 micrograms per litre by the end of 2013.
5 MINIMISING RISK
So we have mechanisms for setting clear standards. We have processes in place to explore and assess potential threats. How then to ensure that the standards are delivered and day-to-day risks minimised? There are a number of partners and all have vital roles:
• There are the water companies, have the legal responsibility for the wholesomeness of public water supplies;
• There is the Drinking Water Inspectorate. The main role of the Drinking Water Inspectorate is to ensure that Water Companies supply water which complies with the standards set down. This it does mainly through regular audit of compliance data and by regular inspection of the Companies. Any deficiencies identified are required to be rectified by the Company;
• Responsibility for monitoring the wholesomeness of private water supplies rests with Local Authorities. Local authorities have legal obligations to inspect and take action when necessary; and
• The Environment Agency monitors and enforces environmental water standards.
6 DRINKING WATER INCIDENTS
When an event affects, or is likely to affect, the wholesomeness or sufficiency of drinking water supplies the Drinking Water Inspectorate is the focal point for receiving notifications made by water companies. It assesses the information provided and the actions taken by the company. If there were contraventions of standards, a decision is taken as to whether initiate enforcement action and, if water unfit for human consumption was supplied, whether a prosecution should be initiated.
In an emergency, the Inspectorate would be involved in providing technical and scientific advice to those managing the emergency. This would include advice to my Department and to Ministers.
Although we tend to take for granted clean and wholesome drinking water, this remains on of my Department's key objectives. There is no room for complacency. It is vital that we retain the confidence of consumers in the safety of drinking water supplies by maintaining high standards.
7 ENVIRONMENTAL WATER QUALITY
Turning from drinking water to environmental quality standards, the Environment Agency is the main organisation responsible for protecting and improving the environment – including the water environment – in England and Wales. The Agency's objectives include:
• tackling flooding and pollution incidents;
• reducing the impacts on the environment from industry and agriculture;
• cleaning up rivers, coastal waters and contaminated land; and
• improving wildlife habitats.
The way in which environmental quality standards for water are applied is crucial to their effectiveness, and the associated compliance regime must be appropriate. In England and Wales, environmental quality standards for surface waters are used by the Environment Agency to calculate emission standards in conditions in discharge consents, as well as to assess the quality of the aquatic environment.
It is worth adding that a range of approaches is possible when applying standards. Typically in the UK, they are determined by obligations under European and UK legislation and expressed in Regulations. This is particularly true of aquatic standards. However, there is also role for more flexible measures, such as general binding rules, codes of good practice or voluntary agreements.
The application of environmental quality standards for the aquatic environment has played a crucial role in improving the chemical quality of the aquatic environment in England and Wales over the past 10 years.
The work carried out over the past 20 years on aquatic environmental quality standards and their related compliance regimes has provided regulators here with a far better understanding of the impacts of risks posed by pollutants and has enabled the UK to contribute positively to discussions on standards at a European level. An example is the Water Framework Directive.
As with drinking water, we also need to ensure that we are looking ahead. New issues – such as the potential effects of endocrine disrupting substances – need to be properly studied and understood.
8 EMERGENCIES
Returning to the theme of this conference - can we cope? We can set standards. We can set up processes for enforcement. We can seek to anticipate future threats. But, we will not always be successful. If contamination does occur, how resilient is the system? Will consumers still be able to get basic services? Will the environment continue to be protected?
For drinking water, each water company is required to have emergency arrangements in place to cope with what they have judged to be their worst-case scenario. These plans are reviewed annually. They include measures enabling one company call upon the help of another – mutual aid. We have, as you might expect, reviewed these arrangements following 11 September.
We have also been providing a series of briefings on· security matters to boards and senior managers of most water companies as well as Scottish Water and OFWAT. We have worked with the industry and the Environment Agency and Scottish Environment Protection Agency to develop a Protocol for the Disposal of Contaminated Water. Work has been started to identify suitable methods of treatment of contaminated water, to permit subsequent safe disposal.
In the last resort, if drinking water is contaminated arrangements exist to ensure that there is an alternative supply.
Where contamination affects environmental quality, the option of alternative supply is rarely available. Instead, the focus is, rightly, upon how the effect can be minimised or contained.
The Environment Agency has long-established procedures for dealing with contamination and potential contamination to ground and surface waters. These procedures are designed to ensure there is effective control and co-operation between the emergency services, local authorities and water industry.
9 CONCLUSION
To sum up, we have, in England and Wales, seen a steady increase in the quality of drinking water and in the aquatic environment. In 2001, 99.86% of the 2.8 million tests showed compliance with the standards. Breaches of the standard were one twelfth of what they were in 1992. There were no reported confirmed cases of cryptosporidiosis related to the mains drinking water supply. 98% of coastal bathing waters met the European Bathing Water Directive and 94% of rivers were of good or fair chemical and biological quality. There is much to protect.
But things can go horribly wrong. Past success is no guarantee of success in the future and where mistakes have been made in the past we must learn from them. Contingency Planning has always been important. It has never been more so. Ministers have made it very clear to water companies and the regulators that they expect robust plans to be in place. An aim that I am sure that you will share. Your conference could not be more timely. I hope that it will help address issues such as where are the gaps? What further needs to be done? Are the lead responsibilities clear? And how can we learn from each other?
Unfortunately, I will not be able to stay for the full term, but my colleagues Nigel Cartwright and John Gray will be here. I will be interested in their report back. The next three days represents a rare opportunity to compare notes; to find the read across from different situations and perspectives; and to look beyond the immediate.
I would not be surprised if it was concluded that aspects of our present systems do warrant further scrutiny. We must be ready to respond so that water supplies continue to meet the standards consumers expect, the environment is protected, and we have a system which is resilient to attack.
Thank you. Have a good conference.
CHAPTER 2
THE CITY OF MILWAUKEE CRYPTOSPORIDIUM OUT BREAK: WHAT REALLY HAPPENED AND HOW VULNERABLE ARE WE?
D E Huffman
College of Marine Science, University of South Florida, 140 7th Ave. South St. Petersburg, Florida, USA
1 INTRODUCTION
It has been 10 years since the City of Milwaukee, Wisconsin's drinking water became contaminated with the protozoan parasite Cryptosporidium parvum. This single drinking water outbreak would become the focal point of hundreds of research studies focusing on the cause of this outbreak as well as methods for the prevention of future outbreaks of this magnitude. Could this outbreak have been prevented and what have we learned over the last decade with regard to Cryptosporidium parvum?
2 CRYPTOSPORIDIUM
If we begin with the basic biology of this organism, Cryptosporidium parvum belongs to the phylum Apicomplexa (referred to as the Sporozoa) and is one of approximately 5,000 species. It is a coccidian parasite that infects the gastrointestinal tract and has become one of the most important enteric pathogens in both humans and animals. The parasite was first described in 1907 by Tyzzer but over the last two decades there has been an escalation of published material on the biology, genomic characterization, taxonomy, transmission, detection and public health risks associated with this organism. There are currently ten recognized species within the genus Cryptosporidium, namely, C. baileyi and C. meleagridis found in birds, C. felis found in cats, C. muris found predominately in mice, and C. wrairi in guinea pigs, C. andersoni in cattle, C. nasorum found in fish, C. serpentis found in reptiles and C. saurophilum in skinks, but the species of concern from both a medical and veterinary perspective is C. parvum (2). Current research has identified two different genotypes of Cryptosporidium parvum that are infectious in humans. Genotype 1 isolates, which have only been shown to be infectious in humans and genotype 2 isolates which have been shown to be infectious in mice, calves, lambs, goats, horses as well as humans. This suggests the possibility that there are two distinct populations of oocysts cycling in humans with distinct transmission cycles; 1) zoonotic transmission from animal to human with subsequent human to human and human to animal transmission and 2) a transmission cycle exclusively in humans. While the number of species and genotypes of Cryptosporidium may seem highly technical and unrelated to the question of what really happened and the vulnerability of Milwaukee, it will become clear that determining the source of the contamination would provide information to assist in the determination of system vulnerability.
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Excerpted from Water Contamination Emergencies by K.C. Thompson, J. Gray. Copyright © 2004 The Royal Society of Chemistry. Excerpted by permission of The Royal Society of Chemistry.
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