Canadian Consulting Engineer

Cover Story: Water Treatment: Changing Times: Providing drinking water in a Post-Walkerton World

wo cartoons shown by presenters at the 10th Canadian National Conference and 1st Policy Forum on Drinking Water held in Halifax April 27-30 summed up the mood. One drawing was of a small boy holding a...

June 1, 2002   By Bronwen Parsons

wo cartoons shown by presenters at the 10th Canadian National Conference and 1st Policy Forum on Drinking Water held in Halifax April 27-30 summed up the mood. One drawing was of a small boy holding a water gun. To the consternation of his mother, he was being arrested by the local cop for being in possession of a dangerous weapon. The other cartoon was of people at a management meeting, whose voice balloons showed them endlessly caught in circles as they defined and redefined their goals.

The water gun was an obvious image for a post-Walkerton world where the substance of life has come to be feared as a potentially deadly fluid. Almost every session at the Halifax conference reverberated around the tragedy in rural Ontario. By an eerie coincidence, as several speakers took pains to point out, the date of the last conference in Regina in May 2000 coincided exactly with the time when E. coli 0:157:H was creeping into well No. 5 in Walkerton.

As for the cartoon of the management meeting, it captured the sense some of us attendees had of being trapped in the fuzzy world of endless planning and policy making. Since this was a “policy forum” (sponsored by the Federal-Provincial-Territorial Drinking Water Subcommittee of Health Canada), there was no shortage of government experts presenting goals for developing various drinking water guidelines and management plans. Their bullet point lists were often tiresomely abstract or self-evident, and the duplication left one wondering why so many different governments and regions cannot combine their efforts in an area where surely the science can be applied universally.

Source to tap

That the Walkerton tragedy has brought a sea change in the water supply industry was clear. For the microbiologists who research the science, the government planners who set the policies, and the engineers and municipalities who design and run the infrastructure, the world is never going to be the same. Consequently, they turned out in record numbers in Halifax to see what the future holds in store. The Canadian Water and Wastewater Association that organizes the conference seemed almost overwhelmed by their success. They had 350 attendees — more than double the number of the last conference — and ran out of programs. And for the first time in 10 years some sessions were open to the public.

The shake-up from Walkerton has been felt throughout Canada. Almost every municipality and every provincial government is re-examining and restructuring the way it delivers water. Those that moved too slowly have been warned. Eleven months after Walkerton, the residents in North Battleford, Saskatchewan, suffered their own outbreak. Approximately 7,100 people suffered from a waterborne infection caused by crytospyridium, likely from a sewage treatment plant located an incredible two kilometres upstream from the raw water intake. Walkerton’s E. coli caused 2,300 to become seriously ill. Sixty-five of them were hospitalized, half of those infants, and there were seven deaths.

Among the policy makers intent on finding ways to avoid such crises in the future, the mantra is a “multi-barrier” approach. The term means taking a holistic, “source to tap” perspective on protecting water quality, where every stage of the delivery journey is taken into account, starting with watershed protection, through treatment and distribution and monitoring.

Michle Giddings, manager of the water quality program with Health Canada in Ottawa, elaborated on the multi-barrier approach. She is on the Federal-Provincial-Territorial Subcommittee on Drinking Water, a body of 25 or so experts charged with drawing up the national Guidelines for Canadian Drinking Water Quality. “Since Walkerton and New Battleford there is no such thing as the status quo,” she began. As a result of the extraordinary circumstances, the subcommittee has departed from its normal work to produce a special guidance document on the multi-barrier approach called “From Source to Tap.” It was being finalized in May.

Michael Brodsky, president of his own company in Thornhill, Ontario, advocated a particular method for achieving a multi-barrier approach to water systems. He described the Hazard Analysis Critical Control Point (HACCP) procedure which was developed for the space program and is now used in the food and drug industry.

Brodsky’s main point was that we should be preventing pathogens entering the water system in the first place instead of relying on detecting them afterwards. He said it is no use depending on traditional fecal indicators to detect the presence of E. coli since coliforms can be formed by thermal industrial processes like pulp and paper and vegetable processing plants. Current methods for detecting protozoas and enteroviruses are inadequate and the organisms are not killed by chlorine disinfectant. Any point in the system where there is loss of control, he said, will present a risk.

Ignoring the signs

Steve Hrudey’s intimate knowledge of the Walkerton case made for a gripping presentation to lead off the conference’s second day. Hrudey, a professor at the University of Alberta and an engineer, is helping to write revisions to the Australian drinking water guidelines. He was also on a panel advising the Commissioner for the Walkerton Inquiry. He and others had studied the literature on outbreaks in other developed countries to find out whether there were any warning signals for what went wrong in Walkerton. They took 15 examples of waterborne outbreaks in Denmark, the U.S., England and Canada, and found six involved heavy rainfall or snow melting, while 10 involved inadequate or no chlorination — the very causes of the problems in Walkerton. Hrudey also cited U.S. research that found 51% of 548 outbreaks in the U.S. over the past 50 years were preceded by heavy rainfall (Curriero et al, 2001).

As we all now know, the Walkerton town system became infected from contamination in well No. 5 when heavy spring rain for several days caused cattle manure to run off and seep into the town’s supply well. The well was on a family farm, and the farmer — the local veterinarian — was exonerated of blame. The utility manager, Stan Koebel, had been falsifying the plant’s chlorine residual reports for years, and he had avoided adding the treatment because people complained of the taste. With not enough disinfectant being added, the fatal coliform was free to do its dirty work.

Even worse, a hydrogeology report 20 years before had warned about the potential problems of the Walkerton well, said it needed chlorination and that farm animals should be kept away from the surrounding area. None of the authorities had followed up on this report, just as none of the officials — neither from the town nor from the provincial government Ministry of the Environment — had noticed Koebel’s aberrant treatment reports.

In short, it wasn’t a matter of poor engineering but of incompetent management and inadequate safeguards. As a result, the entire town’s systems had to be pumped, all sewage was flushed, lines swabbed, five kilometres of water main were replaced and 1,800 buildings had to be sealed and disinfected. The financial costs were estimated at $65 million, and the emotional and health damage were devastating. Hrudey said that Chapter 2 of the Walkerton Inquiry Part I report which describes the impact on the community should be required reading for anyone responsible for water infrastructure.

Dollars are what count

If Walkerton and North Battleford were a wake-up call for Canada, the question now is what safeguards governments should put in place to guarantee a more safe and reliable supply. Some municipal officials expressed frustration that Canada has no national Drinking Water Act and many speakers noted that the usual rivalries between different levels of government is preventing the federal government taking more control. Though there is a private member’s bill — S.18 — currently working its way through Parliament to make water part of Canada’s Food and Drug Act, most speakers thought it would not likely be passed. Meanwhile se
veral provinces have been impelled to develop drinking water regulations or management plans, including Ontario, New Brunswick, Manitoba, Quebec and British Columbia.

Economic issues threaten to stifle the best intentions of any government to improve the safety of drinking water. Ontario, for example, may have already set the regulatory bar too high. In one of the final sessions, for example, Glenn Schwendinger, manager of public works for the rural township of East Perth in south-central Ontario, explained that the town had to shut down four of its six municipally operated water supply systems because the regulations required them to add expensive new equipment and monitoring practices. When users’ annual bills went from $700 to $2,500, plus $6,700 for the capital equipment upgrades, property owners decided to hook up to private wells or dig their own. As Schwendinger wrote in his abstract: “The end result of this process was that four municipally operated, fully regulated, inspected, and monitored wells which supplied a total of 58 users have been replaced with approximately 30 privately operated, unregulated wells supplying the same number of users.” The end result, in other words, of Ontario’s Regulation 459 in this case has been less guarantee of safe drinking water rather than more.

A comment heard in many sessions at this conference was that governments need to face up to the financial issues more realistically and be honest about them with the public. Enormous expense is necessary to absolutely guarantee the safety of water, and several speakers doubted that people are willing to pay in full for the costs through higher taxes or user fees. If a water-rich country like Canada has such problems, imagine how the odds stack up against the Third World. Dr. Jamie Bertram of the World Health Organization spoke about the enormous challenge of bringing clean water and sanitation to the 2.5 billion people on the planet who don’t yet have them. He seemed apologetic when he said that some policymakers are now talking about settling for “targets” of safety, and allowing for “tolerable problems” in any water supply.

Would Canadians ever accept that their tap water might not be 100 per cent safe? If not, are they willing to pay the heavy price for protecting watersheds, for building new plants with expensive new treatment processes, and to support a network of monitoring bureaucrats? For the next few years it is going to be up to governments and the policy makers who proliferated at this conference to make that call.


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