“One project, one review”: Ontario signs cooperation agreement with Canada as it pushes to streamline impact assessments

As it has done or is seeking to do with other provinces, the federal government recently signed a cooperation agreement with Ontario to streamline and expedite project assessment processes. The purpose of these agreements is to minimize duplication between provincial and federal impact assessments and outline the respective roles and responsibilities of each government, including when and under what circumstances each government will lead a project’s assessment.

What you need to know

• Cooperation agreements. The agreements seek to decrease duplication while increasing certainty and transparency on jurisdictional roles in project assessments. They specify when a harmonized process incorporating both provincial and federal expertise will be used, and when full substitution, which allows the federal government to rely on the provincial process, may occur.
• Importance. Until now, British Columbia was the only province with a cooperation agreement to address the process that would be applied in the province for assessments under the Impact Assessment Act (IAA). The two designated projects that have been approved so far under the IAA were both subject to substitution.
• More agreements. This month, Ontario and New Brunswick signed cooperation agreements with the federal government. Alberta has signed an MOU to negotiate a cooperation agreement by April 2026, while Manitoba and Prince Edward Island have published draft cooperation agreements with the federal government. Negotiations are ongoing in other provinces, including Québec.

Canada’s current assessment landscape

Projects in Canada often face extensive regulatory requirements and assessment obligations at multiple levels. A key challenge has been the overlapping responsibilities for environmental protection shared by federal and provincial governments. The Supreme Court of Canada’s 2023 decision in Reference re Impact Assessment Act explored these issues, referring to concerns raised by provinces, Indigenous groups and industry over the federal regime’s unnecessary duplication and lack of federal-provincial coordination¹.

In response to the Supreme Court’s decision, Canada amended the federal Impact Assessment Act in 2024 to better align with the government’s commitment to achieve “one project, one assessment”. The mandate of the IAA now provides that Canada, the Minister of the Environment (the Minister), the Impact Assessment Agency (the Agency) and federal authorities, in administering the IAA, “must exercise their powers in a manner that … promotes cooperation among jurisdictions”².

The following IAA sections shape how federal and provincial processes interact, enabling Canada to develop and enter into cooperation agreements:

• Section 12 specifies that, for the purpose of preparing a possible federal assessment, the Agency must offer to consult with any jurisdiction that has powers, duties or functions related to assessing the environmental effects of the designated project.
• Section 16(2)(f.1) requires the Agency, when determining whether a federal assessment is required, to consider “whether a means other than an impact assessment exists that would permit a jurisdiction to address the adverse effects within federal jurisdiction”.
• Section 31(1) grants the Minister authority, upon the request of the relevant jurisdiction, to approve the substitution of the federal assessment process and its activities with a provincial process.
• Sections 114(1)(c), (d) and (f) authorize the Minister to enter into agreements or arrangements with other jurisdictions to facilitate assessments. These provisions allow for agreements to be made with other jurisdictions respecting the exercise of powers in relation to impact assessments, coordination, consultation, information exchange and the factors to be considered in assessing the effects of designated projects.

Against this regulatory backdrop, cooperation agreements specify, among other things, when a single harmonized process incorporating both provincial and federal expertise may be used, and when full substitution (of the federal process by the provincial process) will instead occur. Rather than undergoing two separate reviews, the province can, under substitution, lead a single process on behalf of both governments, using its own procedures and timelines. Based on BC’s experience with its cooperation agreement, the result has been a reduced regulatory burden, elimination of duplicative assessments, and expedited timelines (compared to a two-assessment scenario).

The federal government highlighted cooperation agreements as a key tool to realize its “one project, one review” goal in the May 2025 Speech from the Throne. During the Speech, the government committed to reaching cooperation agreements with each interested province and territory within six months. Budget 2025 reinforced this priority, emphasizing the use of cooperation agreements to accelerate assessments for projects of national interest and to “signal to investors that Canada’s federal, provincial, and territorial governments are committed to working together to enable development, while protecting Indigenous rights and the environment”³.

Final and draft cooperation agreements

To date, there are five cooperation agreements under the IAA, either finalized or in draft form. The agreements set out how the respective governments will work with the federal government to coordinate project assessment and regulation. The recitals affirm each parties’ jurisdiction, commitment to engaging in meaningful consultation with Indigenous Peoples, and the principles of transparency, efficiency and timeliness.

British Columbia

Signed in September 2019, the BC agreement was, until recently, the country’s only finalized and executed cooperation agreement⁴. Under this framework, several project assessments have proceeded by way of substitution, allowing the BC Environmental Assessment Office to conduct the assessment process under provincial assessment laws⁵. Two of those projects were approved under the IAA: the Ksi Lisims LNG - Natural Gas Liquefaction and Marine Terminal Project⁶ and the Cedar LNG Project⁷. Canada has noted that the Cedar LNG Project was completed in just 3.5 years⁸.

Ontario and New Brunswick

Ontario finalized its cooperation agreement on December 18, 2025, with only minimal changes from the draft announced on November 19, 2025. The New Brunswick cooperation agreement was announced on September 19, 2025, and finalized on December 16, 2025. Interestingly, the finalized version includes a new recital affirming the goal of more expeditious assessments, with New Brunswick supporting “Canada’s commitment to ensure all federal assessment decisions are rendered within two years”.

Manitoba and Price Edward Island

The draft Manitoba agreement was published on November 19, 2025, while the draft PEI agreement was published on November 3, 2025.

Next steps in federal-provincial cooperation agreements

As the Ontario and other cooperation agreements come into force, they provide the potential to significantly reduce regulatory burden and expedite projects. How they will be implemented in practice will be key.