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Water Safety Plans for O&M Improvements

Water Safety Plans for O&M Improvements. Water Safety Conference Kuching, Malaysia 2- 4 November 2010 Asoka Jayaratne Water Quality Specialist Yarra Valley Water Melbourne, Australia. Outline. Linkage between Water Safety Plan (WSP) and operation & maintenance (O&M)

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Water Safety Plans for O&M Improvements

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  1. Water Safety Plans for O&M Improvements Water Safety Conference Kuching, Malaysia 2- 4 November 2010 Asoka Jayaratne Water Quality Specialist Yarra Valley Water Melbourne, Australia

  2. Outline • Linkage between Water Safety Plan (WSP) and operation & maintenance (O&M) • Lessons learned from poor O&M practices • WSP as a tool to drive O&M improvements • O&M framework for safe water Yarra Valley Water Ltd

  3. Why Do We Need Water Safety Plans? • Aim of water supply system • Provide safe drinking water • Provide safe drinking water 100% of the time Does zero E coli mean safe drinking water? Yarra Valley Water Ltd

  4. Linkage between WSP and O&M WHO Framework Health-based targets (National regulatory body) Public health context and health outcomes Water Safety Plans System Assessment Management Plans Operational Monitoring System Assessment Independent Surveillance (Surveillance agency)

  5. Water resources & sources Distribution system Treatment Consumer system Linkage between WSP and O&MWater Safety Plan Concepts • A documented plan that: • Identifies hazards, assesses risks from catchment to consumer • Prioritises risks focus on highest risks • Mitigates risks through control measures • Meaning: • Less outputmonitoring (final water) • More input monitoring (is the system working?) 17 November 2014 Yarra Valley Water Ltd 5

  6. Linkage between WSP and O&MWHO Manual – WSP Components

  7. The Link Water Safety Plan Good O&M Processes Well developed O&M Procedures = Effective Water Safety Plan = Safe water 100% of time Poor O&M Procedures = ineffective Water Safety Plan = Potentially unsafe water 17 November 2014 Yarra Valley Water Ltd 7

  8. Poor O&M = Unsafe Water Supply Lessons from the past…. 17 November 2014 Yarra Valley Water Ltd 8

  9. Gideon, Missouri, 1993 • Hazard (contaminant): • Salmonella • Hazardous event (cause): • Pigeons nesting on a water tank roof • Tank roof was not sealed and pigeon faeces washed into the tank • There was a concentration of Salmonella bacteria in the water tank sediment and at the surface • The water tank rapidly drained into the distribution system during a flushing event and chlorine residual was not maintained • Effect • ~ 500 ill from town of 1,104 • 7 Dead 17 November 2014 Yarra Valley Water Ltd 9

  10. Milwaukee, Wisconsin, 1993 Hazard (contaminant): Cryptosporidium oocysts Hazardous event (cause): Runoff from heavy spring rains Carrying sewage into Lake Michigan (from which raw water was drawn) Coagulation problems on the filtration system in Milwaukee’s Southern water treatment plant Turbidity did not rise above 1.7 NTU Effect: 400,000 ill from 1.2 million in city 100 dead US$96.2 million • www.ionizers.org/images/cryptosporidium.jpg acd 2 March 2006 MacKenzie et al, 1984; Corso et al, 2003 17 November 2014 Yarra Valley Water Ltd 10

  11. Oulu, Finland, 1998 • Hazard (contaminant): • Campylobacter • Hazardous event (cause): • Water and sewer burst at the same time and place • The water main was repaired and flushed out but traces of sewage remained in the water main • Traces of Campylobacter remained in the water main after it was reinstated • The supply was not a chlorinated one • Effect • ~ 50 medically attended cases from town of around 15,000 17 November 2014 Yarra Valley Water Ltd 11

  12. Walkerton, Ontario, 2000 Hazard (contaminant): E. coli O157:H7 Campylobacter jejuni Hazardous event (cause): Heaving Spring rains Cow manure washed into the well No on line monitoring Failure to chlorinate Water supplied by local water utility Operators, managers & government cutbacks found responsible Effect 2,300 ill 7 Dead $ C$155 million www.cdc.gov/ncidod/eid/vol5no1/altek2b.jpg www.ehagroup.com/epidemiology/illnesses/images/e-coli-0157-h7-C.jpg acd 2 March 2006 17 November 2014 Yarra Valley Water Ltd 12 O’Connor, 2002

  13. Distribution system re-contamination 32% of waterborne disease outbreaks in US are caused by microbial pathogens in the water distribution system Source: AWWA and Centres for Disease Control and Prevention

  14. The List goes on!!400 + outbreaks in affluent countries 17 November 2014 Yarra Valley Water Ltd 16

  15. Water Safety Plans for O&M Improvements Yarra Valley Water Ltd

  16. Driver for O&M Improvements WSP Drives Improvements Structure to identify gaps in routine/emergency maintenance Identify gaps in operational procedures based on level of risks Infrastructure upgrades leading to improved operations Benefits Longer term cost savings due to reduced incidents and events Improved operational efficiency 17 November 2014 Yarra Valley Water Ltd 18

  17. WSP for O&M ImprovementsAustralian Examples – Yarra Valley Water Gaps in tank inspection and maintenance program Improved spot chlorination method Improved storage area security procedures 17 November 2014 19 Yarra Valley Water Ltd

  18. WSP for O&M ImprovementsAustralian Examples - YVW Equipment calibration programs Treatment chemical (hypochlorite) QA procedures storage and shelf life impurities batch control Water quality focus on water mains construction and replacement process – new industry Code Incident and emergency management protocols 17 November 2014 Yarra Valley Water Ltd 20

  19. WSP for O&M ImprovementsExamples from India Pilot WSP - Hyderabad Metropolitan Water Supply and Drainage Board Identified O&M issues based on level of risk  funding requirements Leakage from sewers Infiltration from storm water drains Illegal sewer connection 17 November 2014 Yarra Valley Water Ltd 23

  20. WSP for O&M ImprovementsExamples from India Pilot WSP - Hyderabad Metropolitan Water Supply and Drainage Board Treatment plant operational issues Non uniform dispersion of chlorine Inconsistent alum dosing Sand filter backwash not based on head loss Non representative lab sample program Inadequate chlorine residual monitoring 17 November 2014 Yarra Valley Water Ltd 24

  21. O&M Plan - Key Components Standard Operating Procedures (SOP) for operation of water supply system from the catchment to consumer including Operational Manuals Procedures for programmed and unscheduled (emergency) maintenance activities Emergency and Incident Management Protocols and Manuals Equipment calibration and maintenance programs Asset information data capture and management systems 17 November 2014 Yarra Valley Water Ltd 25

  22. O&M Plan - Key Components Key Performance Indicators (KPI) Monitoring, reporting & review of KPI (government regulated/self regulated) Long term asset management strategy and funding arrangements Staff and contractor training programs Quality Control / Quality Assurance systems, internal and third party Auditing (of WSP, O&M process and KPIs) 17 November 2014 Yarra Valley Water Ltd 26

  23. O&M Plan Examples - Storage Reservoir water quality monitoring program off take levels Normal operation Events (floods, after fires, algal blooms) Reservoir inspection program - security Algae management plan Contingency plan for high rainfall events 17 November 2014 Yarra Valley Water Ltd 27

  24. O&M Plan Examples - Treatment Maintenance program – filters, equipment….. Water treatment plant operational procedures Operations and Emergency Response Manuals Contingency plans for treatment plant failures Treatment chemical quality control procedures 17 November 2014 Yarra Valley Water Ltd 28

  25. O&M Plan Examples - Distribution Storage tank operational procedures – taste and odour, chlorine…. Storage tank structural inspection and cleaning program Valve and hydrant inspection programs Water main break repair procedures (flushing, disinfection, shut down) Mains replacement program (prioritised based on risks) Backflow/cross connection prevention program Asset information system - data collection, analysis and reporting 17 November 2014 Yarra Valley Water Ltd 29

  26. Time to develop a Good O&M Planto deliver safe water Yarra Valley Water Ltd

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