Blog: The Walkerton Tragedy- Lessons Learned and Unfinished Business


In May 2000, seven people died, and thousands of people fell seriously ill, after consuming contaminated drinking water supplied by a municipal drinking water system in Walkerton, Ontario.

On the 18th anniversary of this tragedy, it is appropriate to reflect upon some of the lessons learned from this public health catastrophe, and to identify further steps that are necessary to prevent a recurrence of this event elsewhere in the province.

First and foremost, the Walkerton disaster confirms the ongoing need for a robust “multi-barrier” approach to drinking water safety. In the two-volume Walkerton Inquiry report, Mr. Justice O’Connor strongly endorsed this approach, which consists of five key components:

  • preventing contaminants from entering water that is used for drinking water purposes;
  • treating and disinfecting drinking water through effective methods;
  • securing the distribution system and ensuring the delivery of safe water to consumers;
  • performing appropriate monitoring and testing programs; and
  • implementing timely responses to adverse test results or upset conditions.

Second, the necessity of strictly enforcing drinking water rules is another lesson learned from the Walkerton Tragedy. In this regard, Mr. Justice O’Connor recommended greater provincial use of mandatory legal tools (e.g. orders, prosecutions, etc.) to enforce “all regulations and provisions related to the safety of drinking water.”

The third lesson that emerged from the Walkerton Tragedy is that laws, regulations and standards aimed at protecting public health should not be characterized – or cut – as wasteful “red tape”. On this point, Justice O’Connor was highly critical of the Ontario government for creating a “regulatory culture” that discouraged new environmental regulations, including those needed to safeguard public health. This view was recently – and correctly – endorsed by the Toronto Star editorial board.

After the Walkerton Tragedy occurred, the Ontario Legislature enacted three key laws intended to implement the multi-barrier approach: the Safe Drinking Water Act, 2002, Nutrient Management Act, 2002, and Clean Water Act, 2006 (CWA).

Under the CWA, for example, multi-stakeholder Source Protection Committees (SPC’s) were established to develop comprehensive Source Protection Plans to safeguard drinking water sources from degradation or depletion. At the present time, there are 22 provincially approved Source Protection Plans, and these Plans are now being implemented by various public authorities.

However, the mandatory policies in these Source Protection Plans are essentially limited to protecting water used by municipal residential drinking water systems, which serve about 80% of Ontario’s population. This means that private well clusters in rural areas, and source water used by other non-municipal systems across Ontario, receive no direct protection from the new legal tools under the CWA.

This alarming discrepancy prompted the Auditor General of Ontario to recommend that “to strengthen source water protection, the Ministry of the Environment and Climate Change should consider the feasibility of requiring source protection plans to identify and address threats to sources of water that supply private wells and intakes.” However, in her 2016 report, the Auditor General found that the provincial government has made “little or no progress” on this recommendation.

Similarly, it is well-documented that drinking water supplies in many First Nations communities in Ontario are contaminated and/or subject to lengthy boil water advisories. While the province has committed to provide “in-kind technical assistance” to First Nations in relation to drinking water, CELA submits that Ontario should work collaboratively with these communities to develop and fund effective source water protection plans, as recommended by Mr. Justice O’Connor.

Almost two decades after the Walkerton Tragedy, CELA submits that it is highly unacceptable that the CWA regime has been selectively applied in a manner that only protects source water for some – but not all – residents of Ontario.

Accordingly, CELA has consistently requested the provincial government to take all necessary steps to expand the next round of the CWA source protection planning process to include wells and intakes which supply water to certain non-municipal systems.

similar request has recently been made by four SPC’s in eastern Ontario, which advised the provincial government that “it is the concern of many [SPC] Chairs that the multiple barrier concept implemented in southern Ontario capturing municipal water supplies, has not been extended to vulnerable populations in other situations.”

However, the Ontario government is refusing to act upon such requests, and instead claims that it is open to municipalities to use their discretionary Planning Act powers to protect groundwater or surface water resources that supply non-municipal systems. In CELA’s view, this claim is unpersuasive for various reasons (e.g. cost and complexity of source protection planning, inherent limitations on the efficacy of Planning Actinstruments, etc.), and potentially leaves non-municipal drinking water sources at risk.

In short, this is not the time for complacency about drinking water safety throughout Ontario. CELA therefore submits that the Ontario government must immediately address this important unfinished business under the CWA.