Environmental Impact Assessment Report

Posted March 12, 2026

The draft Environmental Impact Assessment Report (EIAR) was available on the Project Website for comment from December 1, 2025 until January 6, 2026. The Ministry of Transportation has updated the draft EIAR in accordance with Section 8 of the Highway 413 Act, 2024. Any concerns raised during the comment period by the public, federal and provincial agencies, municipal representatives, Indigenous communities, and other interested persons have been reviewed and summarized in the final EIAR.

The EIAR describes the Preliminary Design of the Highway 413 Project. The report outlines:

Cover page of the Highway 413 Final Environmental Impact Assessment Report, March 2026, with Ontario, WSP, and AECOM logos.

Description of Highway 413
- A statement on the purpose of the Project and a description of the Project, based on the Preliminary Design.
Development of the Preliminary Design
- Maps showing the location and preliminary designs of the Highway 413 Project, including the extensions of Highway 410 and Highway 427.
- Descriptions of the various alternatives considered for the Highway 413 Project as well as the rationale for selecting the current alignment.
Environmental Considerations
- A summary of the local environmental conditions.
- A description of the environmental studies completed for the Project, potential environmental impacts, and proposed mitigation measures.
- A description of how mitigation will be carried forward, assessed, and monitored during future design phases.
- A list of provincial, federal or other authorizations which may be required for the Project.
Consultation and Engagement
- A record of consultation and engagement with regulatory agencies, the public, stakeholders and Indigenous communities.

Publishing the final EIAR marks the end of the Preliminary Design phase of the Highway 413 project. The Project will transition into the Detail Design phase, which will include further refinements and continued consultation. The EIAR can be found below. Discipline specific impact assessment reports will be available in the coming weeks.

In accordance with Section 8 of the Highway 413 Act, 2024, the final Environmental Impact Assessment Report was posted to the Project Website on March 12, 2026.

Environmental Impact Assessment Report Documents

Busy multi-lane highway with cars and trucks moving in both directions. Sun rises or sets behind a distant city skyline, with trees lining the roadside.

Highway 413 Information Centre

Visit the Highway 413 Information Centre for further information on the EIAR, including a summary of environmental studies and an Interactive Map to further explore Highway 413's Preliminary Design.

Learn more about the Information Centre

How to Navigate the Document

See below for more information on the content included in each chapter of the EIAR.

Chapter 1: Overview of the Undertaking

Chapter 1 introduces the Highway 413 Project, outlining its purpose and role in Ontario’s transportation system. It provides background information about the project and highlights key milestones.

The chapter also explains the Highway 413 Act, 2024, and the steps undertaken to meet these legislative requirements, including the preparation and submission of the EIAR. Finally, Chapter 1 outlines the main topics covered in the report.

Chapter 2: Local Environmental Conditions and Engineering Studies

Chapter 2 presents a detailed overview of the environmental and engineering studies undertaken to support the EIAR. It describes the studies, data collection processes and summarizes existing conditions. The information is organized into four main areas: natural environment, social and economic environment, cultural environment, and engineering studies.

The natural environment section examines ecological features, including fish and fish habitat, terrestrial ecosystems, groundwater and hydrogeology, fluvial geomorphology, erosion and sedimentation, and drainage and stormwater management.

The social and economic environment analysis considers land use, agriculture, landscape, noise, air quality, waste and contaminated property, climate change, community wellbeing, and snowdrift.

The cultural environment content evaluates built heritage resources and cultural heritage landscapes as well as archaeology.

Finally, the engineering studies address technical considerations including road networks, regional transportation networks, existing traffic conditions, active transportation, freight and commuter rail, public transportation, surface water and drainage, geotechnical investigations, and utilities.

Chapter 3: Description of the Alignments Considered and Rationale for Selecting the Preferred Alignment

Chapter 3 outlines how different possible highway alignments were studied and evaluated, and why the Preferred Alignment, was chosen. It starts by describing the step-by-step process used to evaluate the options, which considered planning, environmental, and technical factors.

The first part of this process was the development of a long list of alignment alternatives that capitalized on transportation opportunities within the Highway 413 Route and the transportation system/network, while avoiding, or where not possible, minimizing impacts to environmental features.

Then a screening process was undertaken to identify the most favourable alignment and interchange locations to be carried forward from the long list to a short list using three basic screening principles:

Minimize impacts to significant natural features, functions, systems and communities.
Minimize impacts to existing and planned (approved Official Plans) population and employment areas.
Ensure the interchange movements are efficient and direct, and address the transportation problems and opportunities.

A detailed evaluation of short-list of viable alignments was initiated to select a Technically Preferred Alignment. The evaluation included the identification of advantages and disadvantages on the various short-listed alternatives under consideration.

In consideration of feedback received on the Technically Preferred Alignment, additional refinements were made to further minimize potential impacts and a Preferred Alignment was selected.

Finally, Chapter 3 looks at different design alternatives that were considered during the early stages of the Preliminary Design, including alignment refinements, interchange configurations, major watercourse crossings, drainage and stormwater management, and additional support facilities.

Chapter 4: Preliminary Design

Chapter 4 provides a comprehensive overview of the Preliminary Design for the Highway 413 Project, outlining key infrastructure components. It includes descriptions of important features like interchanges (where highways connect to other highways or major roads), crossing roads, and other supporting facilities.

The chapter also talks about technical aspects of the highway, including how traffic will flow, foundations design, how construction will be planned and managed to avoid disruptions, and discusses environmental considerations.

Chapter 5: Impacts and Mitigation

Chapter 6: List of Potential Provincial, Federal or Other Authorizations

Chapter 6 explains the different authorizations needed from provincial and federal governments based on the Preliminary Design. It includes a table that lists the permits, approvals, and statutory requirements that may be required for the Project, organized by the government authority responsible for them.

Chapter 6 also highlights the Memorandum of Understanding on the Assessment of Effects in Areas of Federal Jurisdiction of the Highway 413 Project which was established to facilitate the Government of Canada and Province of Ontario’s collaboration on the Highway 413 Project. This includes the Bilateral Federal Provincial Working Group, which oversees the formation of technical groups to support the assessment of effects and mitigation measures and coordinates further discussions about required authorizations.

Chapter 7: Indigenous Consultation and Engagement

Chapter 7 provides an overview of the Ministry of Transportation’s consultation and engagement process with Indigenous communities. It summarizes consultation and engagement carried out with Indigenous communities since 2012, including a description of the Indigenous Consultation Plan, a list of project notices and meetings, and a summary of comments submitted and concerns raised by Indigenous communities since 2012 and MTO’s responses at the time, including a summary of comments received on the draft EIAR.

Chapter 8: Consultation and Engagement

Chapter 8 describes the consultation and engagement process undertaken throughout the development of the Highway 413 Project and summarizes comments and concerns raised since November 1^st, 2012, including comments received on the draft EIAR. It provides details on various engagement activities with government agencies, municipalities, advisory groups, key stakeholders and the broader public as well as a summary of the feedback received and the Ministry of Transportation’s response at the time.

Chapter 8 is supported by Appendix A, the Consultation and Engagement Record.

Chapter 9: Significant Changes

Chapter 10: Next Steps

Appendix A: Consultation and Engagement Record

Appendix A provides the record of consultation and engagement with government agencies, municipalities, advisory groups, key stakeholders, and the broader public, including a summary organized by key themes of all comments and concerns raised as well as the Ministry of Transportation’s responses at the time; key notice materials; a summary of key meetings held with agencies, municipalities, interest groups, and other stakeholders; and reports summarizing each of the four PICs held between November 2014 and October 2023.

Appendix B: Preliminary Design Plans

Appendix C: Community Value Plan

Appendix C contains the Community Value Plan (CVP), which was developed using public input and includes design recommendations identifying opportunities for landscaping enhancement and proposed protection and restoration measures for existing landscape features impacted by the Project. The CVP includes the creation of green spaces, stormwater management, preserving and enhancing natural habitats, and commemorating cultural heritage. Measures such as planting native vegetation, creating wildlife corridors, and protecting existing ecosystems aim to promote biodiversity, ecological health, and enhance the aesthetic appeal of the Highway 413.

FAQs

What is the Highway 413 Act?

The Highway 413 Act, 2024 is legislation introduced as part of Bill 212 – Reducing Gridlock, Saving You Time Act, 2024. The Highway 413 Act, 2024 creates a new process for assessing the environmental impacts of the Highway 413 Project. This process involves the publication of a draft and final Environmental Impact Assessment Report (EIAR), which includes a description of the studies completed, the assessment of impacts, proposed mitigation measures, and a record of consultation and engagement.

The requirements of the Highway 413 Act, 2024 build upon the considerable work completed to date, including environmental studies and ongoing consultation and engagement, that the Ministry of Transportation has undertaken to advance the work since the commencement of the Project which began in 2007.

What studies informed the assessment of environmental impacts?

Work on the Highway 413 Project began in 2007, and since then, more than 20 environmental and engineering disciplines have been thoroughly studied as part of the Preliminary Design and assessment of environmental impacts process. These investigations have included both hands-on fieldwork and detailed desktop research, as well as consultation and engagement.

To strengthen collaboration and inclusivity, Community Field Liaisons have been involved in the process. This initiative allows Indigenous communities to actively participate in field activities, providing them with opportunities for direct, on-site observation, ensuring that their perspectives and priorities are recognized and integrated into the Ministry of Transportation’s decision-making throughout the Project.

The environmental studies undertaken for the Highway 413 Project include:

Fish and Fish Habitat
Terrestrial Ecosystems
Species-at-Risk
Fluvial Geomorphology
Surface and Groundwater
Erosion and Sedimentation
Navigable Waterways
Landscape
Archaeological Resources
Built Heritage Resources and Cultural Heritage Landscapes
Land Use
Agricultural
Contaminated Property and Waste
Socio-Economic
Air Quality and Greenhouse Gas (GHGs) Emissions
Noise
Climate Change
Human Health
Snowdrift

The built environment, engineering considerations, and existing and future infrastructure considered by the Highway 413 Project include:

Geotechnical
Public Transportation
Surface Water and Drainage
Freight and Commuter Rail
Active Transportation
Utilities
Road Network
Traffic Conditions

How did the Ministry of Transportation incorporate public, stakeholder and Indigenous community input into the selection of the Preliminary Design?

During Public Information Centre #2 held on September 19, September 26 and October 3, 2019, the Ministry of Transportation presented the Preferred Alignment for feedback. The ministry reviewed this feedback and worked diligently with Indigenous communities, advisory groups, municipal staff, agencies, and other stakeholders to establish the Preferred Alignment for Highway 413 and the transit corridor which was announced in August 2020.

Since then, the ministry has continued to advance the Preferred Alignment to develop the Preliminary Design based on the numerous studies completed for the Project and continued feedback.

How will Highway 413 impact traffic?

Commuters may benefit from travel time savings up to 30 minutes for those travelling the full length of Highway 413 during rush hour.

Highway 413 will:

Boost the movement of goods between key distribution centres and major highways like the 401, 427, 400, and 407 ETR.
Ease traffic congestion by taking pressure off local roads, especially from heavy trucks.
Enhance the highway network in the northwest Greater Toronto Area by supplementing and connecting with existing highway infrastructure.
Improve access to communities with strategically positioned interchanges.
Support faster emergency response by providing more direct routes for ambulances, fire trucks, and police.
Connect with transit options through multiple carpool lots located at interchanges.

How will the Ministry of Transportation ensure that the mitigations proposed in the EIAR are implemented?

The draft EIAR outlines commitments for mitigation measures that will be carried forward to future design phases. During Detail Design and construction commitments made in the final EIAR will be implemented, including but not limited to:

Obtaining required permits and approvals.
Continuing consultation and engagement with Indigenous communities, interest persons and stakeholders.
Finalizing the highway design developed during the Preliminary Design phase.

During Detail Design there may be requirements for additional work, such as surveying; testing for soil conditions; environmental studies; determining exact construction material requirements; developing the design for the final implementation of the highway; and drafting construction documents for the purpose of building the new highway, interchanges, bridges, etc. As a result, the mitigation measures outlined in the EIAR may be updated and refined. Environmental mitigation identified during Preliminary Design and confirmed during Detail Design will be implemented during construction.

Is the Ministry of Transportation still required to obtain environmental permits and approvals for the Highway 413 Project?

The Highway 413 Act, 2024 does not precluded the Highway 413 Project from obtaining environmental permits and approvals.

Some authorizations that may be required include but are not limited to:

Fisheries Act, 1985, Authorization
Species at Risk Act, 2002, Permit
Ontario Water Resources Act, Environmental Activity and Sector Registry (EASR)
Endangered Species Act, 2007*
Ontario Heritage Act

*The Species Conservation Act, 2025 was enacted as part of Bill 5 (Protect Ontario by Unleashing our Economy Act, 2025), and should it come into force, would replace the Endangered Species Act, 2007. At the time of writing this EIAR, the Endangered Species Act, 2007 is still in force.

Which Indigenous communities did the Ministry of Transportation consult with throughout the development of the Preliminary Design?

The Ministry of Transportation has a duty to consult, and where appropriate, accommodate Indigenous communities when contemplating actions that have the potential to adversely impact their credibly asserted or established Aboriginal and/or treaty rights. The ministry is also engaging Indigenous communities who are interested in the Preliminary Design of the Project. In addition, the Highway 413 Act, 2024 sets out the process for assessing potential environmental impacts of the Project, including the creation of an Indigenous Consultation Plan.

The ministry is currently consulting with:

Alderville First Nation
Beausoleil First Nation
Chippewas of Georgina Island First Nation
Chippewas of Rama First Nation
Curve Lake First Nation
Hiawatha First Nation
Huron Wendat Nation (also known as “Wendat Nation” or “Council of the Wendat Nation”)
Kawartha Nishnawbe
Mississaugas of Scugog Island First Nation
Mississaugas of the Credit First Nation
Oneida Nation of the Thames
Six Nations Community
- Six Nations of the Grand River’s Elected Council (“Six Nations of the Grand River”) and,
- Haudenosaunee Confederacy Chiefs Council

The Ministry of Transportation is also engaging with the Métis Nation of Ontario on an interest-basis.

What opportunities did the public have to share feedback on the development of the Preliminary Design?

The Highway 413 Project follows a comprehensive consultation program that welcomes engagement and feedback from the public, stakeholders, municipalities, and Indigenous communities through a suite of outreach methods. These include Ontario Government Notices, Public Information Centres (PICs), Community Workshops and Community Value Plan meetings, Project Website, Project Telephone Number (toll-free), Project Email, fact sheets and bulletins, Advisory Group meetings, presentations to municipal councils, meetings with municipal staff (workshops and issue specific sessions), meetings with technical stakeholders (workshops and issue specific meetings), and meetings with other interested parties upon request (property owners and other members of the public, etc.)

Throughout the consultation process for the Preliminary Design, the ministry received over 9,000 comments from the public, via the Project Email or Project Telephone Number (toll-free). This is in addition to the comments received by the ministry at various community, agency, and stakeholder meetings and the four rounds of PICs.

What happens if the Detail Design is inconsistent with the final EIAR?

If there is a significant change, as defined under the Highway 413 Act, 2024, to the Preliminary Design as illustrated in the final EIAR, an addendum will be prepared in accordance with Section 9 of the Highway 413 Act, 2024.

The process is as follows:

9 (1) The Minister shall carry out the following steps with respect to a significant change:

Undertake any studies of the environment in relation to the significant change that the Minister considers appropriate.
Assess any impacts of the significant change on the environment.
Identify how the Ministry will mitigate any negative impacts identified in the assessment under paragraph 2.
Prepare a draft addendum to the final environmental impact assessment report and a final addendum in accordance with this section.

All steps outlined above will be followed, as appropriate.

What are the next steps now that the EIAR is complete?

The publication of the final EIAR signifies that the Preliminary Design phase for Highway 413 is complete. Following this phase, the Project will transition into the Detail Design phase, where the work completed during Preliminary Design will be further refined and developed to a more comprehensive technical level.

Construction efforts will progress on Early Works projects, which include:

Early Works Project #1: Embankment at the 401/407 ETR/413 Interchange (Complete)
Early Works Project #2: Resurfacing and Underpass at Highway 10/Hurontario Street
Early Works Project #3: Underpass at Bovaird Drive

In addition to these projects, advanced works will commence, including the extension of Highway 410. For more information on this project, please refer to the Ministry of Transportation's news release.

Simultaneously, ongoing consultation and engagement with Indigenous communities, key stakeholders, and the public will continue. As well as environmental permitting and targeted fieldwork and research, all of which are essential to support the upcoming phases of the Project.

What is the timeline for Highway 413?

The Preliminary Design phase of Highway 413 is anticipated to be completed in early 2026. Following the Preliminary Design, Highway 413 will proceed to Detail Design.

Detail Design refines the work completed during Preliminary Design and further develops that work to a more comprehensive technical level. It establishes sufficient details to successfully construct the project. As of the publication of the draft EIAR, options and timelines for phasing and the delivery of Detail Design and construction are being explored.

The timing and duration of highway construction depends on numerous factors, including size and complexity of the project, funding availability, procurement method, and timing of environmental clearances and permits, as well as property acquisition.

Environmental Impact Assessment Report