What is an impact assessment

On June 20, 2024, the Budget Implementation Act, 2024, received Royal Assent and brought into force amendments to the Impact Assessment Act (IAA). These changes were made in response to the Supreme Court of Canada’s decision on the constitutionality of the IAA. Over the coming weeks and months, this website along with procedures, policy and guidance documents will be updated to reflect these legislative changes, as required.

The Impact Assessment Act (the Act) and its regulations establish the legislative basis for federal impact assessment in most regions of Canada. To learn about important and essential facts related to impact assessments, consult the questions and answers below.

This overview is written using less technical language to help the public better understand impact assessment. It is not designed to replace formal guidance documents. In the event of any inconsistency between the content of this page and the Act or its regulations, the Act and its regulations prevail.

Impact Assessments at a Glance

Projects—like the building of mines, roads or dams—can have both positive and negative impacts. They can improve cities and towns. They might create jobs, produce energy, or uncover useful resources. They can also cause harm to the environment, people, communities, or economies.

Impact assessments help us understand the possible impacts of these types of projects before they start. Assessments identify the best ways to avoid or reduce a project's negative impacts. They may also find ways to enhance the positive aspects of a project. Their goal is to inform decision-makers about project impacts and ensure the protection of people and the environment.

The Impact Assessment Agency of Canada (the Agency) leads federal impact assessments. The Agency manages the process to collect the information needed to understand potential impacts of proposed projects. During the impact assessment process, various factors are examined. One important factor is whether the project contributes to sustainability. Sustainability means the ability to:

Many parties take part in impact assessments:

Public participation is an essential part of an open, informed and meaningful impact assessment process. Members of the public can identify important benefits of a project. They may also raise areas of concern related to a project. Further, the information provided by participants may help inform project design and lead to better outcomes.

Impact assessments are especially focused on identifying potential problems before they occur. If issues could arise, the impact assessment process takes into consideration ways to mitigate harm: ways to reduce or avoid negative consequences that might arise from a project, should the project move forward. This work is based on the proponent's proposed mitigation measures and other stakeholder input on the mitigation measures.

Once the impact assessment process is complete, the Minister of Environment and Climate Change Canada (the Minister) issues a decision statement to the proponent. This document states the Government's decision about whether the project is in the public interest and allowed to proceed. If the project is approved, it also includes conditions the proponent must adhere to when carrying out the project. One key condition is that the proponent must develop and carry out a follow-up program in consultation with Indigenous groups and relevant authorities. The Agency tracks and reports on these follow-up programs to determine whether the impacts of the project were accurately predicted. This work helps the Agency understand if the conditions were effective in preventing negative effects. Decision statements can also provide a time limit within which the proponent must develop the project.

The decision statement is a legally binding document. The Agency monitors the proponent's compliance with the decision statement through inspections. If the proponent does not comply with the decision statement, it is a violation of federal law and the proponent may be fined.

After the decision statement is issued, the proponent may need to take further steps before proceeding with the project. For instance, it may need to obtain authorizations or permits for the project in accordance with other federal or provincial laws. In some cases, the proponent may also need to meet the requirements of municipalities and Indigenous governments.

If the proponent wants to change part of the project following a decision, proposed changes must be considered by the Minister through an amendment process before the proponent can proceed.

What is an impact assessment?

An impact assessment is a planning and decision-making tool used to assess the potential positive and negative effects of proposed projects. Impact assessments consider a wide range of factors and propose measures to mitigate projects' adverse effects.Footnote 1 They also consider components of follow-up programs (for projects that are allowed to proceed), which verify the accuracy of an impact assessment and the effectiveness of mitigation measures.

Purposes of impact assessment

The purposes of impact assessment include:

Benefits of impact assessment

Impact assessments ensure that better decisions about a project can be made early on, during a project's planning stage. Other benefits include increasing protections for human health, reducing risks of harming the environment, avoiding negative effects, increasing positive effects, and enhanced understanding about project impacts from the input of Indigenous peoples and the public.

What kinds of projects require impact assessments?

Designated projects—listed in the Physical Activities Regulations (aka the "Project List")—may require an impact assessment. Examples include major projects, such as certain mines, oil facilities, bridges, roads and dams. In some circumstances, the Minister may also designate projects that are not part of the Project List.

What is examined during a federal impact assessment?

The following factors must be considered in an impact assessment:

What are the types of assessment under the Act?

There are two types of project-level impact assessments for designated projects: those led by the Agency and those led by an independent review panel. Both types can take place in cooperation with another jurisdiction. They consider the same factors, require public participation, and result in decision statements with enforceable conditions. Both types are also supported by other federal departments and agencies, which are required to provide their specific expertise for project assessments, including scientific expertise about potential effects.

The Act also includes provisions for regional and strategic assessments.

Impact assessments led by the Agency

The majority of impact assessments are led by the Agency and are conducted by employees at one of the Agency's five regional offices across Canada:

Agency staff have expertise in policy, science, law, environmental studies, and more. They work with proponents, federal authorities and other jurisdictions to integrate various types of information during assessments. Agency staff also lead and coordinate opportunities for the public and Indigenous groups to participate in assessments, and produce impact assessment reports that inform decisions about projects.

Impact assessments led by a review panel

Review panels are groups of independent experts appointed by the Agency to conduct impact assessments. Panel members are not government employees and are selected for their knowledge, experience and expertise relative to a project and its potential effects. Members must be free from bias or conflicts of interest related to the project. Review panels are required to hold a public hearing and, similar to a court, can summon witnesses and order witnesses to present evidence.

At the end of their review, panels provide advice to the Minister in the form of a report, which is made available to the public at the same time. This report includes the panel's conclusions and recommendations related to the potential impacts of a given project. The panel also provides input on measures to mitigate project effects. The responsibilities of a review panel are outlined in its Terms of Reference.

Staff from the Agency support the work of independent review panels, providing technical, procedural and logistical support to the review panel through a secretariat. Agency staff on a secretariat have expertise in science, law, environmental studies, and more.

Review panels operate independently from government. Similar to a court, the deliberations of a review panel remain confidential until the review panel submits its assessment report. This obligation of confidentiality applies equally to the secretariat. This protection is necessary to help preserve the independence of the review panel and ensure it is able to conduct its work in a transparent and robust manner.

Cooperation and coordination with other jurisdictions

Sometimes more than one level of government needs to assess project impacts. For instance, the federal government and a province (or another jurisdiction) may both have separate needs for assessing a project. However, because the Government of Canada strives for the objective of "one project, one assessment" in impact assessment, the Act allows for cooperation and coordinated action between jurisdictions.

There are several ways to work with other jurisdictions. For example, jurisdictions can:

For each project subject to a cooperative assessment, the Agency and the other jurisdiction must develop the process for working together. This infographic provides more information about each mechanism for cooperation.

In all cases, the federal government still makes the final decision on whether the project is in the public interest based on the impact assessment report, and the Minister still issues a decision statement with enforceable conditions.

Integrated review panels

When a project includes activities that are regulated by lifecycle regulators,Footnote 6 the Minister must refer the impact assessment to an integrated review panel. The integrated review panel must include representatives from the respective regulator, but the regulator cannot form the majority on the integrated review panel. This ensures that the assessment benefits from the regulator's experience and expertise. In these situations, the requirements of the applicable lifecycle regulator are integrated into the impact assessment process. This results in a more efficient process and reduces duplication, as key regulatory factors are considered in a single assessment. Key factors include safety, licensing requirements, international obligations, and more.

The lifecycle regulators are the:

Regional and strategic assessments

Regional and strategic assessments help the government understand impacts from a broader perspective than project-level impact assessments. These assessments look at regional contexts and strategic factors, including the combined effects of multiple projects and activities. They also inform decisions about future impact assessments.

What are the main steps of the impact assessment process?

The steps of the impact assessment process are organized into five phases:

Can the timelines of the impact assessment process be adjusted?

The Agency may suspend timelines for specific reasons outlined in the regulations during the following steps in the process:

Timelines may be suspended for three reasons:

The Agency can extend the 180-day timeline for the Planning phase up to a maximum of 90 days at the request of another jurisdiction.

Before the start of an impact assessment, the Agency can establish a longer or shorter timeline for the impact assessment phase under certain conditions.

The Agency may, at the request of the proponent, extend the three-year timeline for the Impact Statement phase.

The Minister can also extend timelines for an impact assessment by up to 90 days. The Minister may extend the timeline during the following phases:

Further extensions require Governor in Council approval.

How can the public and Indigenous groups get involved in an impact assessment?

The Act recognizes the importance of meaningful public participation and Indigenous consultation in impact assessment. The Act requires that the public and Indigenous groups have opportunities to get involved in impact assessments. Explore our website for more information on the participation of Indigenous peoples in impact assessment. Public participation plans outline public participation activities for individual impact assessments. They are issued at the end of the Planning phase. These plans outline the objectives of public participation and the engagement opportunities scheduled for different phases of the assessment process. Indigenous engagement and partnership plans outline Indigenous participation and consultation activities for each impact assessment. These plans are developed with potentially impacted Indigenous communities, and shared with the proponent and posted publicly at the end of the Planning phase.

The purpose of developing this plan is to:

Members of the public and Indigenous peoples can participate in multiple phases of impact assessments. Comments and questions are also welcomed throughout the assessment process. See the Canadian Impact Assessment Registry for information on formal comment periods. You can also subscribe to the Canadian Impact Assessment Registry notifications service for emails that provide up-to-date information and announcements on project assessments.

The Agency provides some financial assistance during impact assessments through the Participant Funding Program and Indigenous Capacity Support Program. These programs are open to individuals, incorporated not-for-profit organizations, and Indigenous groups. Funds from these program help people prepare for, and take part in, key stages of assessments. Consult the Funding programs page to learn more.

Where can I find more information about impact assessments?

This page is an introduction to federal impact assessments in Canada. You can learn more by participating in training opportunities.

You can also read more using the links below:

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