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A Case Study:

A Case Study:. THE WALKERTON TRAGEDY. You Snooze………You Lose!!. Walkerton Public Water System. Operated by the Walkerton, Ontario, CA PUC Stan Koebel-general manager, brother Frank was the foreman 3 groundwater sources with chlorine treatment. Events…..May 8-15, 2000.

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A Case Study:

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  1. A Case Study: THE WALKERTON TRAGEDY

  2. You Snooze………You Lose!!

  3. Walkerton Public Water System • Operated by the Walkerton, Ontario, CA PUC • Stan Koebel-general manager, brother Frank was the foreman • 3 groundwater sources with chlorine treatment

  4. Events…..May 8-15, 2000 • Heavy rains, totaling more than 5 inches • Heaviest almost 3 inches • Well #5 was the primary source of water • May 13,14,15 - Frank Koebel performed daily rounds • Standard practice of not checking chlorine • Fictitious log entries

  5. Events….. May 15 • Stan Koebel returns after one week away • turns Well #7 on without chlorination • a new chlorinator had been installed • 3 bac’t samples taken by PUC employee • labels did not show sample location • from PUC workshop?

  6. Events…..May 15 - 17 • May 15 - 4 samples taken • one from the distribution system • 3 from a water main construction site • May 16- all samples are received by the lab • May 17- lab advises Stan Koebel: • 3 samples from the construction site are positive for total and fecal coliforms (E. coli) • other sample suspect • 6 days to notify health authorities

  7. Events…..May 18 - 19 • First indications of widespread illness • members of the public contact the PUC • Stan Koebel assures them ‘the water is safe to drink” • More illness, bloody diarrhea, vomiting • Doctor contacts Health Unit suspecting E. coli. • Health authorities begin an investigation

  8. Events…..May 19 • Stan informs the Health Unit that he thinks the water is ‘OK’ • does not mention positive samples or that Well 7 had been operating without chlorination • If health authorities were aware of test results and Well #7….with no chlorination….. • Boil Water Notice!!!!

  9. Events…..May 19 & 20 • Stan begins flushing and super chlorinating • the residual is elevated in the system and at the wellheads a few days later • Stool sample from a child tests E.coli positive • outbreak is expanding rapidly • Stan informs health authorities of the system residuals • false impression created

  10. Events…..May 21 • E.coli is confirmed • Health authorities issue boil order over AM/FM radio • Doctor contacts Mayor requesting further public notification-no further steps taken

  11. Events…..May 21 & 22 • Walkerton experiences its first death • Health authorities take 20 water samples • Hospital receives 270 calls for serious abdominal pain & diarrhea • Child is airlifted to London, Ontario for emergency treatment. • Stan provides for the first time the May 17 test results • Directs Frank to change the Well 7 log to imply that it had operated with a chlorinator, and provides altered logs to health authorities

  12. The Fallout….. • 7 people die • 2,300 people became ill • Many suffer permanent organ damage • It was all preventable!

  13. Suffering friends and family of lost ones Uncertainty about the future – will it happen again? A Community Devastated……& Loss of Confidence in Services

  14. What Went Wrong?? What Could Have Been Done To Address This?

  15. What Went Wrong?? What Could Have Been Done To Address This? • Chlorine residual & turbidity monitoring daily at Well #5. • Operator training • Inadequate chlorine dosages • Inadequate monitoring • False chlorine residual log entries • Poorly documented bacti sampling locations • Intentional violation of regulations • PUC Board members not well informed and may have delegated their responsibilities

  16. What Went Wrong?? What Could Have Been Done To Prevent This?? • Health authorities needed to be more aggressive • Lab should notify health authorities of lab results directly • Boil Water Notice should have been more broadly disseminated • Stan misrepresented and concealed information • Test results • Chlorinator not operating

  17. Anatomy of the Physical Causes • The Well • Shallow • Casing extended ~ 15 feet • Water table 8 – 40 feet • Nearby surface water influence • Fractured rock • Pathogenic bacteria quickly moved from the land surface to the ground water supply

  18. Anatomy of the Physical Causes • The Farm • Manure spreading, farm owner not faulted • The owner of the farm was using best management and widely accepted practices

  19. Lessons Learned • Who is ultimately responsible for the health of your customers? • What are the weak links in your operations? • Does anyone in your utility approach their job like the Koebel’s? • In the event of an emergency do you have a plan (ERP) in place? Do you know what to do? • Could this happen in your community?

  20. Stan The Man

  21. Walkerton Not An Isolated Case • Milwaukee, Wisconsin • Cabool, Missouri • New York State Fairgrounds • Centers For Disease Control –Reporting Waterborne Disease Incidents and Investigations

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