A recent open letter crafted by National Council of Women of Canada calls on the Government of Canada to adopt “legally enforceable national drinking water regulations applicable in every province and territory”.[1] This raises profound legal, constitutional, and policy issues. While the letter correctly identifies serious concerns relating to drinking water contamination, pesticide exposure, asbestos cement infrastructure, PFAS contamination, and long-term boil-water advisories in Indigenous communities, its proposed action, a constitutional remedy of direct federal responsibility is highly problematic. Under Canada’s constitutional structure, the federal government does not possess broad plenary authority to impose a sweeping national drinking water regulatory regime across all provinces and municipalities. Rather, responsibility for drinking water regulation is primarily provincial, municipal, and local in nature under the division of powers established by the Constitution Act, 1867.[2]
Canada’s constitutional framework intentionally disperses authority over water governance among multiple levels of government. Provinces possess primary jurisdiction over property and civil rights, local works and undertakings, municipalities, public health, natural resources, and most environmental regulations. Municipal drinking water systems are creatures of provincial statute and are generally regulated under provincial environmental protection, public health, and municipal legislation.[3] Consequently, while the federal government possesses important but limited powers over fisheries, navigation, Indigenous lands, criminal law, toxic substances, and interprovincial matters, it cannot simply enact a comprehensive national drinking water code applicable to all provinces without raising serious constitutional concerns.
The constitutional limitations on federal authority in this area have been repeatedly emphasized by the Supreme Court of Canada. Environmental regulation in Canada is characterized as an “amorphous” subject matter that cuts across multiple heads of power rather than a single enumerated constitutional category.[4] As the Supreme Court explained in Friends of the Oldman River Society v Canada (Minister of Transport), the environment is “a constitutionally abstruse matter” involving overlapping jurisdiction.[5] The Court has consistently rejected efforts to centralize broad environmental governance within a single order of government.
Provincial Constitutional Authority over Drinking Water
The strongest constitutional authority relating to drinking water regulation lies with the provinces under section 92 of the Constitution Act, 1867.[6] Provincial powers over “Property and Civil Rights in the Province” under section 92(13), “Matters of a merely local or private nature” under section 92(16), and provincial authority over natural resources under section 92A collectively provide provinces with sweeping jurisdiction over water treatment systems, watershed management, municipal infrastructure, groundwater extraction, and public health protection.[7]
The Supreme Court of Canada has repeatedly interpreted section 92(13) broadly. In R v Hydro-Québec, majority of the judges emphasized that provinces retain extensive constitutional authority over pollution control and environmental management.[8] Similarly, in 114957 Canada Ltée (Spraytech) v Hudson, the Court upheld municipal pesticide bylaws as valid exercises of delegated provincial authority relating to local health and environmental protection.[9]
Municipal water systems themselves derive authority from provincial legislation such as Ontario’s Safe Drinking Water Act, 2002,[10] the Clean Water Act, 2006,[11] and similar statutes across Canada. Provinces determine licensing requirements, treatment standards, testing protocols, operator certification systems, source-water planning frameworks, and enforcement mechanisms. Municipalities operate water infrastructure under provincial delegation rather than federal authority.
The constitutional principle of subsidiarity recognized in Spraytech also supports localized governance over water systems.[12] Drinking water quality varies significantly depending on geology, climate, watershed conditions, infrastructure age, industrial contamination sources, agricultural runoff, and population density. Localized governance allows provinces and municipalities to tailor standards and enforcement to regional realities.
Limits of Federal Constitutional Authority
The federal government nevertheless possesses several important but limited constitutional powers relevant to drinking water. These include criminal law authority under section 91(27), fisheries jurisdiction under section 91(12), federal authority over Indigenous lands under section 91(24), navigation and shipping powers, federal spending authority, and residual national concern jurisdiction under the peace, order, and good government (“POGG”) clause.[13]
However, none of these heads of power likely authorize the sweeping national drinking water regime proposed in the open letter.
Criminal Law Power
The federal government may regulate toxic substances through the criminal law power where legislation includes prohibitions backed by penalties and directed toward a valid public purpose.[14] This authority supported the constitutionality of portions of the Canadian Environmental Protection Act (“CEPA”) in Hydro-Québec.[15] Under CEPA, the federal government regulates toxic chemicals including PFAS, PCBs, mercury, and certain pesticides.[16]
Yet criminal law authority does not provide a general constitutional basis for direct federal management of all municipal drinking water systems nationwide. A comprehensive national water code regulating treatment plants, municipal infrastructure, operator certification, testing schedules, and local source-water planning would likely intrude deeply into provincial jurisdiction over local matters and public utilities.[17]
Peace, Order, and Good Government (POGG)
Some advocates may argue that drinking water constitutes a matter of national concern under POGG. However, the Supreme Court has imposed stringent limitations on the national concern doctrine. In Reference re Greenhouse Gas Pollution Pricing Act, the Court stressed that national concern jurisdiction applies only where a matter possesses sufficient singleness, distinctiveness, and indivisibility.[18]
Drinking water regulation is unlikely to satisfy this test because municipal water systems remain fundamentally local and provincial in character. Water infrastructure, treatment technologies, watershed conditions, and contamination sources vary dramatically between regions. Unlike greenhouse gas emissions, drinking water governance lacks the national indivisibility required under POGG jurisprudence.[19]
If Ottawa attempted to constitutionalize broad federal control over drinking water systems under POGG, provinces would likely challenge the legislation as an unconstitutional intrusion into provincial powers.
Federal Spending Power
The federal government possesses broad spending authority allowing it to fund water infrastructure projects, Indigenous water systems, wastewater upgrades, scientific research, and public health initiatives.[20] Ottawa has extensively used infrastructure funding agreements to influence provincial water policy indirectly.
However, the spending power does not permit unilateral federal regulation of provincial water systems. Provinces may accept or reject conditional federal funding arrangements. Constitutional convention and cooperative federalism generally require negotiation rather than unilateral federal control.[21]
Indigenous Drinking Water and Federal Jurisdiction
The strongest area of direct federal authority relates to drinking water systems on reserve lands under section 91(24) of the Constitution Act, 1867.[22] Federal responsibility for First Nations drinking water has become one of Canada’s most significant environmental justice failures.
Long-term boil-water advisories in communities such as Neskantaga First Nation and Grassy Narrows First Nation illustrate systemic regulatory failures involving underfunding, infrastructure neglect, and fragmented governance.[23] The federal government historically resisted binding regulatory frameworks for reserve water systems while simultaneously failing to provide adequate infrastructure funding.
Parliament enacted the Safe Drinking Water for First Nations Act in 2013[24], but the legislation faced intense criticism from Indigenous organizations, environmental groups, and legal scholars for imposing regulatory obligations without guaranteeing adequate funding.[25] In 2022, the federal government introduced replacement legislation emphasizing recognition of Indigenous water rights and self-governance.[26] Importantly, however, federal jurisdiction over reserve lands does not create general constitutional authority over provincial and municipal water systems across Canada.
The Role of the Canadian Council of Ministers of the Environment
The open letter overlooks the central institutional mechanism through which drinking water coordination already occurs in Canada, through the Canadian Council of Ministers of the Environment (“CCME”). Established in 1964, the CCME functions as an intergovernmental forum through which federal, provincial, and territorial environment ministers coordinate environmental standards, guidelines, research, and policy development.[27]
The CCME reflects the reality of Canadian cooperative federalism. Rather than imposing unilateral national environmental standards, Canada historically relies on negotiated harmonization among governments.
The CCME has played a major role in developing Canada-wide environmental standards (“CWS”), source-water protection initiatives, contaminated site frameworks, wastewater standards, and water-quality guidelines.[28] Closely associated with CCME work is the Federal-Provincial-Territorial Committee on Drinking Water, which develops the Guidelines for Canadian Drinking Water Quality.[29]
These guidelines establish recommended maximum acceptable concentrations for contaminants such as arsenic, lead, PFAS, pesticides, asbestos fibres, E. coli, nitrates, uranium, and trihalomethanes.[30] The guidelines are informed by toxicological assessments, epidemiological evidence, engineering feasibility, and risk analysis.
However, the guidelines are not automatically legally binding. Provinces choose whether and how to incorporate them into provincial regulations.[31] This decentralized implementation model reflects constitutional realities rather than mere political reluctance.
Critics argue that this approach creates inconsistency and weak enforcement. Yet supporters contend that flexible provincial implementation allows adaptation to regional conditions while respecting constitutional boundaries.
Walkerton and the Rise of Source-Water Protection
The constitutional and institutional complexities surrounding drinking water became especially visible following the Walkerton Water Crisis. Contamination of Walkerton’s municipal water supply with E. coli O157:H7 caused seven deaths and thousands of illnesses.[32]
Justice Dennis O’Connor’s inquiry fundamentally reshaped Canadian water governance.[33] The inquiry emphasized the importance of multi-barrier protection systems, operator training, source-water planning, watershed management, and transparent reporting.[34]
Ontario responded with sweeping legislation including the Safe Drinking Water Act, 2002 and the Clean Water Act, 2006.[35] Notably, the response remained provincial rather than federal in character. The Walkerton reforms demonstrated that provinces possess substantial constitutional authority to regulate drinking water comprehensively when political will exist.
Source Water Protection and Federal Constraints
The open letter properly emphasizes source-water protection. Modern environmental policy increasingly recognizes that preventing contamination at the watershed level is more effective than relying solely on end-of-pipe treatment technologies.[36]
Nevertheless, source-water protection frequently implicates land-use planning, agricultural regulation, municipal zoning, conservation authorities, groundwater extraction permits, forestry operations, and local industrial approvals — all areas dominated constitutionally by provincial jurisdiction.[37]
Federal attempts to regulate agricultural runoff, municipal zoning, septic systems, or local watershed development comprehensively would likely face constitutional challenge unless clearly tied to fisheries protection, toxic substances regulation, or Indigenous lands.
The Supreme Court’s environmental federalism jurisprudence consistently favors cooperative approaches rather than constitutional centralization.[38]
International Comparisons and Constitutional Differences
The open letter compares Canada unfavorably to other G7 nations with national drinking water standards. However, these comparisons often ignore constitutional differences.
The United States adopted the Safe Drinking Water Act under expansive federal commerce clause powers unavailable in Canada.[39] European Union member states operate within supranational legal structures fundamentally different from Canadian federalism.[40]
Canada’s constitutional architecture intentionally diffuses environmental authority. This fragmentation may create coordination challenges, but it also reflects deeply embedded principles of regional autonomy and provincial sovereignty.
Cooperative Federalism as the Realistic Path Forward
The most constitutionally viable path forward is likely strengthened cooperative federalism rather than sweeping unilateral federal legislation.
Ottawa can:
- strengthen the CEPA toxic substance controls;
- fund water infrastructure upgrades;
- support Indigenous water governance;
- expand national monitoring programs;
- negotiate stronger intergovernmental agreements through the CCME;
- use spending power incentives;
- enhance public reporting systems; and
- support harmonized provincial implementation of national guidelines.[41]
Such approaches align more closely with Canadian constitutional tradition than attempts to centralize direct drinking water regulation federally.
The Supreme Court increasingly endorses cooperative federalism as a constitutional principle encouraging overlapping but coordinated jurisdiction.[42] Environmental governance in Canada depends less on rigid jurisdictional exclusivity than negotiated intergovernmental collaboration.
Conclusion
The open letter raises legitimate concerns regarding pesticide contamination, PFAS exposure, deteriorating water infrastructure, toxic chemicals, and persistent boil-water advisories in Indigenous communities. Canada’s fragmented drinking water governance system undoubtedly containsweaknesses and inconsistencies.
However, the proposed constitutional solution — sweeping federally enforceable national drinking water regulations applicable across every province and territory — exceeds the likely constitutional authority of Parliament under the Constitution Act, 1867. Primary jurisdiction over drinking water systems remains vested in provinces through their powers over property, civil rights, municipalities, public health, and local works.
Canada’s environmental constitutional framework instead favors cooperative federalism through institutions such as the CCME, negotiated guidelines, conditional funding, provincial implementation, and overlapping but limited federal powers. While this model may appear less centralized than systems in the United States or Europe, it reflects the constitutional realities of Canadian federalism.
The long-term solution to Canada’s water challenges therefore lies not in unconstitutional federal centralization, but in stronger intergovernmental cooperation, enhanced provincial regulation, robust Indigenous water governance, expanded infrastructure investment, strengthened toxic substance regulation, and renewed political commitment across all levels of government.
Endnotes
[1] National Council of Women of Canada (see: OPEN LETTER FOR CANADA TO PROTECT OUR WATER, Feb. 2026); https://www.ncwcanada.ca/open-letter-for-canada-to-protect-our-water
[2] Constitution Act, 1867 (UK), 30 & 31 Vict, c 3, ss 91–92, online: Justice Laws Website – Constitution Act, 1867, ss 92(13), 92(16), 92A.
[3] Ontario, Safe Drinking Water Act, 2002, SO 2002, c 32, online: Ontario Safe Drinking Water Act.
[11] Ontario, Clean Water Act, 2006, SO 2006, c 22, online: Ontario Clean Water Act.
[16] Canada, Canadian Environmental Protection Act, 1999, SC 1999, c 33, online: Canadian Environmental Protection Act, 1999.
[23] Grassy Narrows First Nation and Neskantaga First Nation remain among Canada’s most cited examples of prolonged water-system failures.
[25] Cheryl Currie et al, “Water Challenges in First Nations Communities” (2015) 106 Can J Public Health E283.
[27] Canadian Council of Ministers of the Environment, online: CCME Official Website.
[29] Canada, Guidelines for Canadian Drinking Water Quality, online: Health Canada Drinking Water Guidelines.
[31] David Boyd, Unnatural Law: Rethinking Canadian Environmental Law and Policy (Vancouver: UBC Press, 2003).
[33] Dennis O’Connor, Report of the Walkerton Inquiry (Toronto: Ontario Ministry of the Attorney General, 2002), online: Walkerton Inquiry Report.
[36] Steve Hrudey & Elizabeth Hrudey, Safe Drinking Water: Lessons from Recent Outbreaks in Affluent Nations (London: IWA Publishing, 2004).
[41] Kathryn Harrison, Passing the Buck: Federalism and Canadian Environmental Policy (Vancouver: UBC Press, 1996).
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