Sun Times staff
Justice Dennis O’Connor’s first report on the events of May, 2000 drew together decades of events and oversights that played parts in the deadly outbreak.
He found a heavy rain beginning May 8 washed E. coli and Campylobacter jejuni from a nearby farm into the town’s Well 5, which along with Well 6 and Well 7, provided the town’s drinking water at the time. He found Well 5 to be the source of contamination that killed seven and made about 3,000 people ill, some permanently.
The following timeline is based on Part 1 of the Report of the Walkerton Inquiry.
Walkerton’s Well 5 is drilled shallow in fractured bedrock. It is identified as vulnerable to surface contamination, but no special requirements are made to ensure the water is chlorinated and tested properly.
Ministry of the Environment inspects Well 5 in 1991, 1995 and 1998, but it is not assessed to see if it is directly affected by surface water. Problems with testing and chlorination are identified, but the ministry relies on the Walkerton PUC to fix them without ordering it to do so.
MOE budget cuts start in 1992 and are stepped up after the election of 1995.
Drinking water lab tests are privatized in 1996 without making it necessary for those doing the tests to inform the MOE or local health officials of trouble.
May 8-13, 2000
Heavy rains begin and flooding follows. E. coli and Campylobacter jejuni enter Walkerton’s Well 5 from a nearby farm.
The well is the primary source of drinking water for the system in this period.
Chlorine residual measurements, which in part indicate if the chlorine’s disinfectant capacity is being overwhelmed, are not taken at the well.
It has been common practice at the PUC to make fictitious entries for chlorine residuals. Exposure to pathogens begins for people drinking the town’s water.
May 15, 2000
Water samples are taken by a PUC worker, but they are mislabelled. Samples also taken at a watermain construction site. PUC manager Stan Koebel returns to Walkerton after being away for more than a week and learns the town’s Well 7 has been operating without a chlorinator. He allows it to continue working. Well 5 is turned off, but the contaminated water has entered the system.
May 17, 2000
Private lab informs Koebel water samples taken May 15 are contaminated with E. coli, but lab doesn’t inform the MOE office in Owen Sound or the local health unit.
May 18, 2000
Signs of illness are noted when two children with bloody diarrhea are admitted to hospital in Owen Sound. Many more children are kept home from school and the PUC starts getting calls asking if something is wrong with the water.
May 19, 2000
More students are kept home from school and signs of illness are noticed by more people.
In Owen Sound, pediatrician Dr. Kristen Hallett contacts the health unit with suspicions the two children in hospital in the city have E. coli O157:H7 and notes other people in Walkerton show signs of illness.
Health unit officials phone Stan Koebel and ask if there is a problem with the water. He does not tell them of the adverse lab results, or that Well 7 had been operating without a chlorinator, which is unacceptable. After speaking with the health unit staff, Koebel begins flushing and superchlorinating the system.
“I am satisfied that Mr. Koebel was concerned during the weekend about people becoming ill from the water and he did not know that E. coli could be fatal,” O’Connor wrote.
May 20, 2000
E. coli is found in a preliminary test of one of the children at the Owen Sound hospital, prompting more calls from the health unit to Koebel. Again he doesn’t reveal what he knows about the May 15 lab tests. The health unit assures callers water isn’t the culprit.
A PUC worker makes an anonymous call to an MOE emergency number and says Walkerton water samples have failed lab tests.
May 21, 2000
E. coli O157:H7 is confirmed in tests at the Owen Sound hospital.
Health unit issues a boil water advisory at 1:30 p.m. and takes its own water samples in Walkerton.
There is rapid increase in the number of people affected by the contamination and Walkerton’s hospital is flooded with patients and calls.
The first child is airlifted to London.
May 22, 2000
First person dies. E. coli O157:H7 listed as contributing factor.
The MOE begins its own investigation of the water system at the request of the health unit. It isn’t until the MOE requests documents that Stan Koebel produces a fax sent to him by the lab May 17. He provides daily operating sheets for Well 5 and Well 6, and instructs his brother Frank to alter the documents for Well 7.
May 23, 2000
Second person dies. E. coli O157:H7 listed as cause.
Stan Koebel provides MOE with altered daily operating sheets for Well 7.
The health unit gets back test results showing E. coli is in the town’s water system. When informed, Koebel tells the health unit about the samples from May 15.
May 24, 2000
Two more people die. E. coli O157:H7 listed as cause in both cases.
Many others are transferred to London.
May 29, 2000
Fifth person dies. Campylobacter jejuni listed as contributing factor.
May 30, 2000
Sixth death. E. coli O157:H7 listed as cause.
July 25, 2000
Last death officially associated with outbreak. Campylobacter jejuni listed as a contributing factor.