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2. Session structure Overview Definition & examples Actions Outputs Challenges Exercises Module 4 Control measures & risk reassessment 2

3. Overview Document existing and potential control measures Assess their effectiveness (validation) Recalculate risks accounting for existing control measures Prioritize risks 3 Module 4 Control measures & risk reassessment

4. Control measure definition: Any action or activity that can be used to prevent, eliminate or reduce to an acceptable level any water safety hazard 4 Module 4 Control measures & risk reassessment

5. Examples – Control measures – low tech Cover Well head Designated bucket 5 Module 4 Control measures & risk reassessment

6. Examples – Control measures Module 4 Control measures & risk reassessment 6 Source water protected from livestock Automated chlorine dosing system Module 4 Control measures &

7. Actions Identify existing controls Document need for new control measures as necessary 7 Identify control measures Assess effectiveness Reassess risks Prioritize risks Module 4 Control measures & risk reassessment

8. Actions continued... Assess effectiveness (normal & exceptional circumstances) 8 Validation Investigative activity to identify the effectiveness of control measures. It provides the evidence that elements of the WSP can effectively meet the water quality targets. Module 4 Control measures & risk reassessment

9. Actions continued... Assess effectiveness (normal & exceptional circumstances) Monitoring Not in isolation but as part of process chain Data from studies / historical records Introducing contaminant – testing removal Sanitary surveys 9 Module 4 Control measures & risk reassessment

10. Actions continued... Reassess risks accounting for effectiveness of control measures Based on long-term average performance Highlight where controls are not in place 10 Module 4 Control measures & risk reassessment

11. Actions continued... Prioritize all identified risks Rank the reassessed risks Screen for critical risks 11 Module 4 Control measures & risk reassessment

12. Outputs 12 Module 4 Identification of control measures Validation of control measures Prioritization of risks Module 4 Control measures & risk reassessment

13. Challenges Uncertainty in prioritizing risks Lack of knowledge Poor data Different approaches = different outcome Qualitative versus quantitative Assessing effectiveness of certain controls Catchment – how to measure/enforce? 13 Module 4 Control measures & risk reassessment

14. 14 Exercise In small groups Part 1 (5 minutes) Match up hazardous events with suitable control measures Identify possible control measures for three hazardous events Part 2 (5 minutes) Describe how these control measures can be validated Part 3 and 4 (20 minutes) Reassess the likelihood and severity by considering the implementation of control measures and rank the risks again from highest to lowest Module 4 Control measures & risk reassessment