Transcript Water Safety Plans | November 2010

Household and small
community water safety
Kuching
2 November 2010

Water Safety Plans | November 2010
Bruce Gordon
Water, Sanitation, Hygiene and Health
Guidelines for Drinking-water Quality
(GDWQ)
 Flagship normative
publications of WHO.
– Demand for the document
is among the highest and
most sustained of all WHO
publications.
Water Safety Plans | November 2010
WHO Guidelines for Drinking Water Quality,
Framework for Safe Drinking Water:
 Considers overall public health context and
contribution of drinking-water to disease burden
Health-based targets
(National regulatory body)
 Eventually need to be expressed as Water
Quality, Performance, or Technology Targets
 Risk management plan
Water Safety Plan
(Water utility)
 Implementation of step-wise improvements
 Continuous monitoring
 Documentation and supporting programmes
Independent surveillance
 External audit of WSP
(Surveillance agency)
 Verification monitoring
Water Safety Plans | November 2010
Water Safety Plan (simplified)
What are the risks?
Continuous cycle
Monitoring
Source: Netti et al. 2005
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How do I control
the risks?
Implementing a WSP?
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WSP
Watersteps
Safety Plans
System mapping
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Risk Assessment
Monitoring +
Control measures
Improvements (e.g.
investment planning)
WSPs: Sanitary survey reborn?
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• Paradigm shift (from reactive to preventive)
• But common sense ("sanitary survey +")
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Benefits of WSP approach
 Reduce disease
 Risk-based approach
 Enhance good practice
 Evidence-based investments
 Save money in the long-term
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Small Community Water Supplies – the need for a WSP
approach
 Undertrained operators
 Varying and inconsistent perception of risks
 Unclear roles and responsibilities;
 Limited resources
More frequently associated with waterborne disease in
both developed & developing countries
Water Safety Plans | November 2010
The case for HWTS
 Dramatically improves microbial water
quality
 Significantly reduces diarrhoea
 Among the most effective of water,
sanitation, and hygiene interventions
 Can be rapidly deployed and taken up by
vulnerable populations
Water Safety Plans | November 2010
WHO Guidelines for Drinking-water Quality
 "HWTS has been shown to significantly improve water
quality and reduce waterborne infectious disease risks"
Water Safety Plans | November 2010
Effectiveness ranges of HWTS technologies for the reduction of microbes
in water
Porous ceramic filtration
Protozoa
Settling/sedimentation
Free chlorine disinfection
Viruses
Solar disinfection
Bacteria
UV irradiation
Thermal treatment
Diatomaceous earth filters
Fiber and fabric filters
Household slow sand filtration
Disinfection/coagulation
0
1
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3
4
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Log(10) reduction of microbes
8
Courtesy of Mark Sobsey, University of North Carolina
Water Safety Plans | November 2010
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The Need for a Network
Looking Back: the situation in 2003
• lack of awareness of effectiveness, and cost
effectiveness
• lack of supportive policies
• limited cooperation: fragmented advocacy, research
and implementation efforts
• limited tools available to support implementation
• major gaps in implementation research
Response: Establishment of an International
Network
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Limitations of HWTS
 Does not improve access to water (quantity)
 Does not provide the health and economic benefits
associated with a regular, piped-into home, water supply
 Places the burden of water quality management on
consumers
 Demands a lot from householders, requiring:
– Consistent and sustained behaviour change
– Time investments to manage water
– Financial investments
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Current Evidence (simplified)
Intervention
Effect size Reduction
on diarrhoea (percent)
morbidity
Reference
Water quality, under 12 months
0.56
44%
Waddington et al. 20091
Water quality, after 12 months or more
0.81
19%
Waddington et al. 20091
Sustainable impact
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Challenges
 Has not achieved sustained pubic health impact
 Government have not developed comprehensive policies
or regulations addressing (non-boiling) HWTS options as
part of their overall water safety efforts
 Largely a small-scale intervention undertaken by NGOs in
isolation from central government-formulated drinkingwater supply programmes
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Give up?
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NO!
 For many vulnerable populations, HWTS remains the only
viable approach to rapidly improving water safety
 Immense potential health and other benefits associated
with ultimately succeeding in scaling-up HWTS
 Challenges are significant, but are not dissimilar to those
that had been faced previously by successful current
interventions
– (e.g. bednets to protect against malaria).
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UNICEF and WHO:
7 point plan to control diarrhoea:
Water Safety Plans | November 2010