what are dwsps ? who initiative comprehensive risk assessment and risk management approach...

What are DWSPs ?

• WHO Initiative

• Comprehensive risk assessment and risk management approach

• Source-to-tap

• Multiple-barriers

• HACCP

• Many elements will already be part of existing good practice

More about DWSPs

• They may include quality assurance systems (e.g. ISO 9001:2000)

• However, existing practices may not include system-tailored hazard identification and risk assessment

• See 3rd Edition WHO Guidelines (2004): www.who.int/water_sanitation_health/dwq/en/gdwq3_4.pdf

• Water safety plans: Managing drinking-water quality from catchment to consumer (WHO August 2005) http://www.who.int/water_sanitation_health/dwq/wsp0506/en/index.html

• Water Safety Plan Manual and WSPs for large buildings in preparation by WHO

What are the drivers ?

• Standards on their own do not achieve reliable quality

• For some issues, risk-based approaches are much more appropriate than standards

• In many parts of the world, the need is not for more standards but proper controls and procedures to achieve the existing standards

• Improvement of customer confidence by ensuring quality reliability

• Introduction of proper risk-based management systems

A better way of achieving good water quality

DWSP components

• system assessment to determine whether the drinking-

water supply chain (up to the point of consumption) as a

whole can deliver water of a quality that meets health-

based targets. This also includes the assessment of

design criteria of new systems.

DWSP components

• identifying control measures in a drinking-water system that will collectively control identified risks and ensure that the health-based targets are met. For each control measure identified, an appropriate means of operational monitoring should be defined that will ensure that any deviation from required performance is rapidly detected in a timely manner.

DWSP components

• management plans describing actions to be taken during

normal operation or incident conditions and documenting

the system assessment (including upgrade and

improvement), monitoring and communication plans and

supporting programmes.

The process:• Identify the hazard

• Assess the risk of the hazard reaching the consumer and causing health effects

• Define the barriers and the operational controls that show that the barriers or the process is working at its optimum at all times

• Corrective action that is required to minimise the hazard

• Verify that the corrective action has been successful and has been recorded

DWSP Elements

The scope :-

• Catchment

• Treatment

• Storage and distribution

• Consumers’ premises, including public buildings

Amended Regulations (2007)

• Disinfection• Disinfect (remove or render harmless), and• Sufficient preliminary treatment to prepare it for

disinfection

• Risk Assessment • Water Safety Plan• Treatment works and connected supply system• By 1 October 2008• Risk assessments to be kept under review

Amended Regulations

• Cryptosporidium• Requirement for specific risk

assessment revoked • Transitional arrangements until 1/1/09• Notification arrangements (for

Cryptosporidium)

Drinking Water Protected Areas

• WFD Article 7 establishes a register of Protected Areas

and identifies water used for the abstraction of drinking

water

• All bodies of water used for abstraction for human

consumption providing >10 m3/day (on average) or

serving more than 50 people