Pipeline Profile

Description

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Section updated: October 2024

Disclaimer

The Pipeline Profiles interactive maps provide publicly accessible information about CER-regulated pipeline systems. These maps provide information about the pipeline systems we regulate and allow the user to zoom in and view nearby communities and other geographic features.

The information displayed on this map is not meant to be comprehensive, and some datasets have been filtered to show only the most relevant information. Please see the Interactive Pipeline Map to see a more comprehensive picture of CER-regulated pipelines.

This information is also not intended for locating pipelines for construction activities or any other soil disturbance in the area around a pipeline. Please check our Damage Prevention Website for information on where to Click Before you Dig.

Terms of Use

The Canada Energy Regulator (CER) provides this information for personal and non-commercial uses. The information contained in this map is based on externally sourced information. The CER makes no representations regarding the accuracy of this information. The CER accepts no responsibility or liability for inaccuracies, errors or omissions in the data and any loss, damage or costs incurred as a result of using or relying on the map data in any way.

The pipeline data contained in this map is subject to licensing terms and may not be reproduced, published, distributed or transferred in whole or in part. The map also contains information license under the Open Government License - Canada.

The Canadian Energy Regulator is bound by the Official Language Act and relevant Treasury Board policies. However, some material on these pages originates from organizations not subject to the Official Languages Act and is made available on this project page in the language in which it was written.

Sources and Description

Sources

The information contained in these maps is obtained from the following sources: U.S. Energy Information Administration (EIA) (U.S. Pipelines); Environmental Systems Research Institute, Inc. (ESRI) (The Community Map of Canada); Geomatics Data Management Inc. (GDM) (CER-regulated pipelines); Government of Canada: Natural Resources Canada, and Surveyor General Branch (Indigenous Lands); Government of Canada: Crown-Indigenous Relations and Northern Affairs Canada (Modern and Historic Treaties).

Description

The TC Canadian Mainline Map displays the TC Canadian Mainline and connected pipelines in Canada and the U.S. The TC Canadian Mainline extends from the Alberta/Saskatchewan border across Saskatchewan, Manitoba, and Ontario, and through a portion of Quebec.

History

The TC Canadian Mainline transports natural gas produced primarily in Alberta and British Columbia. The pipeline receives gas from the NGTL system.
The pipeline entered service in 1958. The CER library has the original maps, studies, and transcripts related to the 1950s regulatory process, including the reports that approved the pipeline construction.
Through the Canadian Prairies, the TC Canadian Mainline is comprised of five parallel transmission lines. In 2007, the sixth segment (Line 100-1) was modified and converted to transport crude oil. See the Keystone Pipeline Profile.
Historically, most of the natural gas consumed in Ontario and Quebec was produced in western Canada and transported on the TC Canadian Mainline.
Starting in the late 2000s, growing production from the Appalachian Basin began to impact Canadian market dynamics. U.S. natural gas production increased, and some export points on the TC Canadian Mainline in Ontario were modified to import U.S. natural gas.
The TC Canadian Mainline’s Niagara point has imported natural gas since 2012. The Chippawa point has been importing natural gas since 2015.

Connected Pipelines and Facilities

The TC Canadian Mainline transports natural gas to the Enbridge Gas Dawn Hub via the Great Lakes Transmission System in the U.S.
The Dawn Hub is a complex of storage facilities where natural gas is injected in the summer and withdrawn in the winter when demand for home heating picks up.
The Dawn Hub has approximately 280 billion cubic feet of storage capacity, one of the largest natural gas storage facilities in North America.
The Dawn to Parkway system connects natural gas storage facilities in Dawn, Ontario, with the TC Canadian Mainline. The Dawn to Parkway system is a provincial pipeline and is regulated by the Ontario Energy Board.
South of Ottawa, the TC Canadian Mainline connects with the Iroquois Gas Transmission pipeline. Iroquois is primarily an export point but has periodically imported gas during the winter from 2018 onward.
See CER’s Market Snapshot - Natural gas coming into Canada from New York, U.S.
Near the Ontario and Quebec border, the TC Canadian Mainline connects with the Trans Quebec & Maritimes (TQM) pipeline, which supplies customers in Quebec.
The TQM pipeline also connects with other U.S. systems that supply natural gas to communities in the northeastern U.S., as well as Canadian Maritime provinces.
The capacity of TQM was recently expanded. See: Application for the Blainville Compressor Station and East Hereford Electrical Upgrade [Folder 3874689].
South of Emerson, Manitoba, the Canadian Mainline connects with two pipelines – Viking Gas Transmission and Great Lakes Gas Transmission (GLGT).
Both systems supply customers in the U.S. midcontinent, as well as storage facilities in southern Ontario.
In April 2022, the Federal Energy Regulatory Commission in the U.S. approved the Alberta Xpress project. Using existing capacity on the TC Canadian Mainline and GLGT pipelines, the project will transport 165 million cubic feet of western Canadian gas production to U.S. Gulf Coast liquified natural gas export facilities (FERC docket CP20-484-000).

Reconciliation Content

We recognize that all lands are the traditional and/or treaty territories of Indigenous Peoples, however, in this data set, only treaty lands are represented due to data availability.
For more information about how the traditional territories of Indigenous Peoples in a region are defined, it is best to consult First Nation and Metis governments directly.
For more information about traditional territories and potential or established treaty rights, you may also consult the Aboriginal and Treaty Rights Information System.

Details
References

Section updated: October 2024

Pipeline ownership
Pipeline name	TransCanada (TC) Canadian Mainline pipeline
CER-regulated company	TransCanada PipeLines Limited (TCPL)
Parent company	TC Energy Corporation
Pipeline attributes
Group for financial regulation^{Footnote 1}	Group 1
Commenced operations	1958
Location	The TC Canadian Mainline extends from the Alberta/Saskatchewan border across Saskatchewan, Manitoba and Ontario, and through a portion of Quebec.
CER-regulated pipeline length (km)^{Footnote 2}	14,123 km
Transported commodity	Natural gas
Pipeline capacity	Capacity on the TC Canadian Mainline is variable depending on the specific location key points. At Prairies, the capacity is approximately 6.2 billion cubic feet per day (Bcf/d). At Iroquois, the capacity is approximately 0.6 Bcf/d.
Major interconnected pipelines	NGTL system, TQM pipeline, Viking Gas Transmission pipeline, Great Lakes Gas Transmission pipeline, Empire pipeline, Tennessee Gas pipeline, National Fuel Gas pipeline, Iroquois Gas Transmission system, St. Lawrence Gas Company, North Country Gas pipeline and Vermont Gas systems

Section updated: March 2025

Company:

CER:

Regulatory documents for TransCanada (TC) Canadian Mainline pipeline facility applications: [Folder 90715]
Regulatory documents for TransCanada (TC) Canadian Mainline pipeline toll & tariff applications: [Folder 155829]

Data sets on Open Government:

Use

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Throughput and capacity
Markets

Section updated: November 2024

Throughput and capacity

Section updated quarterly (early March, mid-May, mid-August and mid-November)

Select key point:

Select units:

Bcf/d million m3/d

Key Point Map

Leaflet © OpenStreetMap contributors, GDM

Key Point Trends

Throughputs at the Prairies key point have increased by 11.5% year over year, from an average of 3.64 Bcf/d in Q3 2023 to an average of 4.06 Bcf/d in Q3 2024 (most recent quarter of data).

Throughputs in Q3 2024 are 25% above the five-year average.

Key Point Description

Interconnect with the NOVA Gas Transmission Ltd. (NGTL) system at the Alberta/Saskatchewan border. Empress is one of the primary receipt points on the Mainline. Gas moves east for use in Manitoba, Ontario, Quebec, and exports into the U.S. Midwest and U.S. Northeast.

Annual Average Throughput: Prairies (Bcf/d)

	2006	2007	2008	2009	2010	2011	2012	2013	2014	2015	2016	2017	2018	2019	2020	2021	2022	2023	2024
Intra-Canada	6.0	5.7	5.1	4.3	3.3	3.2	2.3	2.2	3.3	3.0	2.8	2.7	3.1	3.1	2.9	3.3	3.7	3.8	4.1

Note: The physical capacity of a pipeline is based on many factors such as the products being carried, direction of flow, pipeline pumping capacity, and maintenance work or other pressure restrictions. The actual physical capacity of the pipeline may, at times, be higher than the assumed operational capacity stated here.

Dashboard instructions

Click on a key point button above the chart & map to view traffic at a different location. The map shows approximate locations on the pipeline where throughputs & capacity are recorded by the pipeline operator.
Click and drag your mouse on the area chart to zoom into the desired date range. Click on the Reset Zoom button to reset the full date range.
Click on the chart legend items below the chart to remove & add sections of data as required.
The key point trends are calculated using quarterly average traffic at the key point. Natural gas throughput trends are displayed year over year (last full quarter of data compared to the same quarter last year). Crude oil and liquids key point trends are displayed quarter over quarter (last full quarter of data compared to the previous quarter).

Note: The five-year average is calculated for natural gas key points using the total throughput across all trade types and direction of flows. For bi-directional key points (both export and import) the throughput is displayed for both directions, instead of the five-year average.

Source and description

Data Source: Open Government

Description: The above dashboard displays pipeline throughput and capacity at key point(s) along the system. Where possible, the five-year average and five-year range for throughput is shown with the current year throughput to better highlight the trends. For pipeline key points with a defined location, a map is displayed next to the graph showing the approximate key point location where pipeline throughput and capacity are recorded.

A conversion of 1 cubic meter = 35.3147 Cubic feet (cf) natural gas is used in this dashboard

Section updated: October 2024

Markets

The TC Canadian Mainline is one of the major pipelines that transport gas from the Western Canada Sedimentary Basin to export markets in the U.S. The other pipelines are the Alliance pipeline, the Westcoast pipeline, and the Foothills pipelines.

The TC Canadian Mainline transports natural gas produced in western Canada to customers in eastern Canada and the U.S. Since the mid–2000s, some export points on the eastern portion of the Mainline were reversed to become import points to bring natural gas produced in the Appalachian Basin into Canada.

A list of shippers on the TC Canadian Mainline is available on TC Energy's website (Contract Demand Energy, Future Contract Demand Energy reports). The report provides data on how this pipeline is used and who uses it. The report lists a broad range of users including power producers, industrial users and local distribution companies across Canada and the U.S., including customers in Nova Scotia and New Brunswick.

Transportation costs (tolls)

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Section updated: August 2024

A toll is the price charged by a pipeline company for transportation and other services. Tolls allow pipeline companies to safely operate and maintain pipelines. Tolls also provide funds for companies to recover capital (the money used to build the pipeline), pay debts, and provide a return to investors. The interactive graph below shows Mainline tolls on major long-haul and short-haul paths. Long-haul paths have Empress as a receipt point, while short-haul paths have receipt points east of Saskatchewan, such as Union Parkway Belt.

In April 2020, the CER approved the 2021-2026 negotiated settlement between TCPL and TC Canadian Mainline shippers [Folder 3891141]. The settlement fixes firm tolls on the TC Canadian Mainline for a period of six years, between 1 January 2021 and 31 December 2026, and segmented the system into the Western Mainline Segment and Eastern Triangle Segment for tolling purposes.

From 2007 to 2011, the TC Canadian Mainline operated under a negotiated settlement based on a cost of service model. In 2011, TCPL filed a toll application [Folder 711778]. The NEB’s Reasons for Decision in March 2013 resulted in lower multi-year fixed tolls for Firm Transportation service. It also gave TCPL discretion in the pricing of Interruptible transportation (IT) service and Short Term Firm Transportation (STFT) service. When the decision was implemented in mid-2013, firm contracts from Empress increased.

At the end of 2013, TCPL and three eastern local distribution companies applied for a new toll regime incenting TCPL to build new facilities in the Eastern Triangle [Folder 2397890]. It was approved in December 2014, resulting in higher tolls that were determined based on the TC Canadian Mainline’s cost of service. This toll methodology was expected to be in place from 2015 to 2020, with a review in 2017. In December 2017, TCPL filed an application for 2018-2020 Mainline Tolls and the NEB issued Reasons for Decision in December 2018 [Folder 3413374].

Between 2017 and 2019, the NEB approved several Long Term Fixed Price (LTFP) services, which provided lower tolls in order to retain or attract volumes to the system [Folder 3173691], [Folder 3224371], [Folder 3715883].

Note that the natural gas distribution company, Gaz Métro, was renamed to Énergir in late 2017. Subsequently, the delivery point GMIT EDA was renamed to Energir EDA.

Official CER documents related to the traffic, tolls and tariffs for the TC Canadian Mainline can be found here: TCPL toll documents [Folder 92843].

Data Source and Description

Data Source: Open Government

Description: The above chart displays tolls data for the pipeline system. Only major or benchmark toll paths are shown for illustrative purposes. To see tolls for all available system paths, see the tariff filing.

Pricing discretion for firm and interruptible transportation

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Section updated: January 2021

The TC Canadian Mainline offers several transportation services on its pipeline. Interruptible transportation (IT) service has lower priority than firm transportation (FT) so it may be subject to curtailment. IT is auctioned daily to the highest bidder – above bid floors set by TCPL. Short term firm transportation (STFT), which has a minimum term of seven days and a maximum term of one year less a day, is also auctioned to the highest bidder (above a specified bid floor). Current and historical bid floor levels for IT and STFT, by path, are available on TC Energy’s website.

Biddable IT and STFT services for the TC Canadian Mainline came into effect July 2013, following the NEB’s RH-003-2011 Decision [Document A51040-1] . Since May 2015 TCPL files additional monthly information for IT and STFT services in its Quarterly Surveillance Reports [Folder 155521], including posted bid floors by path, total contracted quantities, number of counterparties and total monthly revenues. This information is available in the dashboard below. IT revenues can turn negative if there are volume imbalances on the system. These imbalances may arise when shippers nominate or re-nominate volumes on the pipeline, but subsequently do not utilize all of the transportation capacity and tariff provisions are prompted.

Section updated: August 2024

Data Source and Description

Data Source: This data is submitted to the CER on a quarterly basis [Folder 155521].

Description: This dashboard shows the quantities of natural gas sold using the interruptible transportation service and the revenues collected. Data is available for each transportation path on the pipeline (i.e., from a receipt point to a delivery point).

Section updated: August 2024

Data Source and Description

Data Source: This data is submitted to the CER on a quarterly basis [Folder 155521].

Description: This dashboard shows the quantities of natural gas sold using the short-term firm transportation service and the revenues collected. Data is available for each transportation path on the pipeline (i.e., from a receipt point to a delivery point).

Section updated: August 2024

Data Source and Description

Data Source: This data is submitted to the CER on a quarterly basis [Folder 155521].

Description: This dashboard shows the prices for interruptible transportation service expressed as a volume weighted toll or as a percentage of the daily firm transportation toll. Data is available for each transportation path on the pipeline (i.e., from a receipt point to a delivery point).

Section updated: August 2024

Data Source and Description

Data Source: This data is submitted to the CER on a quarterly basis [Folder 155521].

Description: This dashboard shows the prices for short-term firm transportation service expressed as a volume weighted toll or as a percentage of the daily firm transportation toll. Data is available for each transportation path on the pipeline (i.e., from a receipt point to a delivery point).

Abandonment funding

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Section updated: October 2024

The CER requires all pipeline companies to set aside funds to safely cease operation of their pipelines at the end of their useful lives. In 2016, TCPL estimated it would cost $2.9 billion to do this for the Mainline. In 2024, this number was revised to $4.1 billion. These funds are being collected and set aside in a trust. Collection period end date is December 31, 2043.

Table 1: Canadian Mainline’s abandonment trust fund balance
	2019	2020	2021	2022	2023
Trust fund balance ($)	816,400,000	1,013,600,000	1,149,600,000	1,148,500,000	1,347,700,000

Official CER documents related to abandonment funding can be found here, sorted by year and by company: abandonment funding documents [Folder 3300366].

Financial information

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Section updated: October 2024

Pipeline companies report important financial information to the CER quarterly or annually. A solid financial position enables companies to maintain their pipeline systems, attract capital to build new infrastructure, and meet the market’s evolving needs. The data in this table comes from TC Canadian Mainline’s Quarterly Surveillance Reports [Folder 155521].

Table 2: Canadian Mainline financial data
	2015	2016	2017	2018	2019	2020	2021	2022	2023
Revenue (million $)	2,396.9	2,127.9	1,900.2	1,771.7	1,487.4	1,430.7	1,570.9	1,714.4	1,762.5
Net Income (million $)	200.7	187.4	180.5	169.2	161.8	155.2	199.8	214.4	218.2
Rate Base (million $)	4,617.2	4,073.8	3,923.9	3,678.5	3,534.3	3,568	3,544.4	3,579.4	3,570.3
Return on Rate Base (%)	9.01	9.3	9.54	9.46	9.32	8.92	8.71	9.28	9.66
Deemed equity ratio (%)	40	40	40	40	40	40	40	40	40
ROE (%)	10.86	11.5	11.5	11.5	11.44	10.87	14.1	14.97	15.28

Disclaimer

The financial information presented in Table 2 reflects regulatory information prepared by each CER-regulated pipeline company and filed quarterly or annually with the CER. This information is filed to inform shippers, the CER and other interested parties on pipeline revenues and expenses and is used in monitoring pipeline transportation costs. Methodologies used in the preparation of this financial information may reflect regulatory decisions and guidance and unique negotiated agreements between a pipeline company and its shippers and interested parties. These methodologies, and the resulting financial information presented, may not follow established accounting principles used in other corporate reporting, and may not be comparable between different CER-regulated companies. For more information, please see the regulatory documents in CER’s REGDOCS and any associated notes contained within them.

Section updated: October 2024

The TC Canadian Mainline is owned and operated by TCPL. TCPL has operations in Canada, the United States and Mexico and operates three core businesses: natural gas pipelines, liquids pipelines and energy.

Credit ratings provide an idea of the financial strength of a company, including its ability to attract capital to build new infrastructure and meet financial obligations. The credit ratings below are expert opinions of how likely the debt issuer is to live up to its obligations. TransCanada also publishes recent credit ratings on its website. TCPL’s credit ratings remain investment grade.

Table 3: TCPL credit ratings
Rating Agency	2015	2016	2017	2018	2019	2020	2021	2022	2023
DBRS credit rating	A (low)	A (low)	A (low)	A (low)	A (low)	A (low)	A (low)	A (low)	A (low)
Moody's credit rating	A3	A3	A3	A3	Baa1	Baa1	Baa1	Baa1	Baa1
S&P credit rating	A-	A-	A-	BBB+	BBB+	BBB+	BBB+	BBB+	BBB+

Section updated: March 2025

The CER audits pipeline companies to confirm compliance with the Canadian Energy Regulator Act, regulations, CER orders, and CER decisions. Financial regulatory audits focus on toll and tariff matters such as detecting cross-subsidies. The Canadian Mainline’s last audit was completed on July 25 2022.

Official CER documents related to the Canadian Mainline’s financial regulatory audits can be found here: [Folder 571547].

Safety and environment

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Section updated: November 2024

Section updated quarterly (early March, mid-May, mid-August and mid-November)

Section updated: November 2024

Conditions Compliance

Every pipeline company in Canada must meet federal, provincial or territorial, and local requirements. This includes Acts, Regulations, rules, bylaws, and zoning restrictions. Pipelines are also bound by technical, safety, and environmental standards along with company rules, protocols and management systems. In addition to these requirements, the Commission may add conditions to regulatory instruments that each company must meet. Conditions are project-specific and are designed to protect public and the environment by reducing possible risks identified during the application process.

Condition compliance is part of the CER's oversight and enforcement action is taken when required.

Conditions can be related to a specific region, or apply to the pipeline project as a whole. The map below displays the number of in progress and closed conditions mapped to economic regions as defined by Statistics Canada.

Conditions can typically be either in-progress or closed. The CER follows up on in-progress conditions.

In-Progress

This status refers to conditions that continue to be monitored by the CER. This happens when:

condition filings have not yet been received by the CER; or,
filings have been received but are under review or do not yet meet requirements; or,
a project is not completed and it has conditions, which have not been met; or,
a project has a post-construction condition, but a requirement has not yet been completed; or,
some conditions may be active indefinitely or refer to the continued operation of a pipeline.

Closed

This status refers to:

condition requirements that have been satisfied, and no further submissions from the company are required; or
conditions whose filings or actions apply to a specific phase that have been fulfilled as the phase is completed (i.e. a specific filing during construction phase). Note: comments on the required actions can still be received.

Dashboard: TC Canadian Mainline - In Progress Conditions by Region

Some conditions are not tied to a geographic location.

No geographic location summary for TC Canadian Mainline:

Closed conditions: 14

Dashboard instructions

Click on a region to view conditions info
Click map area outside of regions to hide info

Note: Some conditions apply to multiple regions. Conditions may be double counted across regions, resulting in a higher number of conditions than the totals seen in the buttons above.

Source and description

Data Source: Open Government

Description: The above map displays the number of CER conditions associated with projects approved by the Commission. The map is split into two tabs which show in-progress and closed conditions separately, mapped to an economic region. If a company has no in-progress conditions specific to an economic region, the dashboard will default to show the closed conditions by region. An additional view is available which contains the number of in-progress and closed conditions that don't have a corresponding economic region in the dataset. The map regions are shaded based on the number of conditions, with lighter coloured regions containing fewer conditions compared to darker colors. Conditions that apply to more than one region are double counted in the map, and these conditions will appear in the map region total and map region breakdown for each applicable region. The condition counts contained in the map navigation buttons represent total conditions without region double counting.

Have you checked out the CER's interactive conditions data visualization? This tool offers a deep dive into the CER's conditions compliance data and process, exploring conditions across all CER regulated companies by keyword, project, and location.

Section updated: November 2024

Reported Incidents

The information presented here is based on CER data (2008 to current) for incidents reported under the Onshore Pipeline Regulations and the Processing Plant Regulations. New data is added quarterly. Learn more on how incident data collection has evolved since the NEB (now the CER) was established in 1959.

Companies must report events, such as incidents, to the CER in accordance with the CER Event Reporting Guidelines. Knowing what happened, and why, helps us find ways to prevent them from happening again.

What is an incident? (Onshore Pipeline Regulations (OPR))

As defined in the OPR, “incident” means an occurrence that results in:

the death or serious injury to a person;
a significant adverse effect on the environment;
an unintended fire or explosion;
an unintended or uncontained release of low vapour pressure (LVP) hydrocarbons in excess of 1.5 m³
an unintended or uncontrolled release of gas or high vapour pressure (HVP) hydrocarbons;
the operation of a pipeline beyond its design limits as determined under CSA Z662 or CSA Z276 or any operating limits imposed by the CER.

What is an incident? (Processing Plant Regulations (PPR))

As defined in the PPR, “incident” is defined as an occurrence that results or could result in a significant adverse effect on property, the environment, or the safety of persons. For the purposes of incident reporting in the PPR, events that fall under this definition include, but are not limited to:

the death or serious injury to a person;
a significant adverse effect on the environment;
an unintended fire or explosion that results in or has the potential to result in damage to company, public/crown or personal property;
an unintended or uncontained release of low vapour pressure (LVP) hydrocarbons in excess of 1.5 m³
an unintended or uncontrolled release of gas, HVP hydrocarbons, hydrogen sulfide or other poisonous gas; or
the operation of a plant beyond its design limits or any limits imposed by the CER.

Incidents and the CER

Companies self-report incidents and are expected to take a precautionary approach in doing so. This means that even when there is doubt as to whether an incident should be reported, the company must report it. The approach is, “When in doubt, report.” This is consistent with CER-regulated companies’ responsibility for anticipating, preventing, mitigating and managing incidents of any size or duration.

The CER reviews all reported incidents to assess whether companies have taken the appropriate corrective actions and to identify potential trends in incidents. Each incident is given a status indicating the current stage of the CER's incident review.

CER Status

Initially Submitted: The company has notified the CER that an incident has occurred and provided preliminary information. A review has been initiated.
Submitted: The company has submitted all of the required information and the CER is reviewing the incident.
Closed: The CER’s incident review has been completed and the file is closed.

The TC Canadian Mainline has reported a total of 238 incidents since 2008. Of those incidents, 75 have resulted in some volume of product being released, with natural gas - sweet being the most commonly released substance. The dashboard below provides some more information about these product release incidents.

Part of the CER's incident review classifies incidents based on the circumstances that directly led to the incident (what happened), and the underlying reasons for the incident (why it happened). On this pipeline system, the most common what happened is corrosion and cracking and the most common why it happened is maintenance . Take a look at the incident trends section of the dashboard below for definitions and a breakdown of what and why.

The dashboard below displays only the incidents that resulted in a release of product from the pipeline, however there are other important incident types that may not appear on the dashboard. Of TC Canadian Mainline's reported incidents, 1 has resulted in adverse environmental effects. There have been 4 serious injuries, and 0 fatalities related to incident events. Open the dropdown below to view the definitions of these incident types.

Incident type definitions: one incident can have multiple types

Release of Substance (featured in the dashboard) - Any time a product is unintentionally released. (Releases of non-gas low pressure products in volumes of less than 1.5 m³ are exempt from reporting.)
Adverse Environmental Effects - When any chemical substance is released at a concentration or volume that has the potential to change the ambient environment in a manner that would cause harm to human life, wildlife or vegetation (e.g., glycol, potassium carbonate, methanol, methanol mix from hydrostatic testing, etc.).
Explosion - An unintended explosion
Fatality - Any death involving employees, contractors or members of the public related to the construction, operation, maintenance or abandonment of pipelines
Fire - An unintended fire
Operation Beyond Design Limits Includes situations, such as:
- over-pressures - i.e., pressures that are higher than the maximum the equipment was designed to safely handle;
- vibration beyond design limits;
- slope movements causing movement in the pipeline beyond design limits;
- pipe exposures in rivers or streams; and
- introduction of an inappropriate product (e.g., sour gas in excess of CSA limits)
Operation beyond design limit is typically linked to an over-pressure of the product in the pipe; however, if a pipe was exposed to excessive vibration and was not designed for this, this could be considered operation beyond design limits. Operation beyond design limits does not include equipment contacting the pipe, or corrosion pits, etc.
Serious Injury (CER or Transportation Safety Board) - Any serious injury involving employees, contractors or members of the public related to the construction, operation or maintenance of pipelines.

Dashboard: TC Canadian Mainline - Incidents with a product release

Leaflet © OpenStreetMap contributors, GDM

Substance

CER Status

What Happened

Why It Happened

Province

Source and description

Data Source: Open Government

Description: The above map displays the location of product release incidents that have occurred on the pipeline system since 2008. The map defaults to show incidents as bubbles which are coloured based on the substance released. Incidents on the map can be re-categorized based on the most recently available status of the CER's incident review, the year in which the incident was reported, and the province/territory where the incident occurred. The incident map bubble can be switched to show the estimated volume of product released, with larger map bubbles showing larger release volumes relative to other product releases on the system. The incident data can also be toggled to display a stacked bar chart of incidents over time by clicking on the incident trends button above the map. The stacked bars display the number of product release incidents by year, with bar colour segments corresponding to the various products released. Similar to the map, incidents can be re-categorized by clicking on the side buttons to view a breakdown of incidents by status, what happened, why it happened, and province/territory.

Have you checked out the CER's interactive incident data visualization? This tool offers a deep dive into the CER's incident data trends, exploring incidents across all CER regulated companies.

Section updated: November 2024

Operations and Maintenance Activities

Oil and gas pipeline companies regularly conduct routine operations and maintenance (O&M) activities on CER regulated pipelines. These activities include things such as pipeline repairs, investigative and integrity digs, and many other activities while promoting safety, security, environmental protection, economic efficiency, and respect for the rights of those that may be affected.

Companies are required to adhere to Canadian Energy Regulator Act’s Onshore Pipeline Regulations and operate their facilities in a manner that is safe and protects the environment. Authorizations for pipelines typically allow companies to construct and operate a facility, and companies are not required to apply for additional approval to undertake most O&M activities. In certain circumstances, companies are required to notify the CER in advance with sufficient information to make a determination as to whether to inspect O&M activities that could result in safety consequences to landowners or the public, environmental consequences, or a negative impact on normal third-party use of the right-of-way (ROW) or adjacent property.

What activities are O&M activities (eligible activities)?

Operations and maintenance activities include:

All activities necessary to safely operate an existing pipeline;
Maintenance activities, upgrades or repairs to an existing pipeline or part of a pipeline that do not increase the approved maximum operating pressure (MOP), the stress level or diameter of the pipeline; or
Physically removing an existing section of pipe up to 5 km in length, and putting a new section of pipe in its place, as long as this replacement does not increase the approved MOP, stress level or diameter of the pipeline.

What O&M Activities require CER approval (restrictions on eligible activities)?

Where any of the following restrictions exist, the company must apply to the Commission in accordance with the CER Act and the related regulations and may not carry out the proposed activity until approval from the Commission has been obtained. The restrictions apply where:

The work includes welding on an in-service pipeline by a pipeline company that has not previously performed in-service welding in accordance with the requirements of CSA Z662-15, Clause 7.17, ‘Welding on In-Service Piping’, or the equivalent clause in the most recent edition of CSA Z662; or
The work involves the construction of an aerial crossing, excluding work on company owned or leased land relating to facilities (e.g., terminal stations, processing plants, compressor/pump stations).

What kinds of activities are not O&M activities (ineligible activities)?

O&M activities do not include:

Upgrades that result in increases above previously approved and specified levels to:
- the MOP,
- stress levels,
- the diameter of the pipeline, and/or
- airborne emissions or noise levels.
"Looping" (i.e., adding pipe parallel or adjacent to, and interconnected with, an existing pipeline for the general purpose of increasing capacity);
Construction of a new pipeline; or
Deactivation (for longer than 12 months), reactivation (where a pipeline has been deactivated for more than 12 months), decommissioning, or abandonment.

The dashboard and figures presented below only include O&M activities from 2015 onwards that require notification to the CER. Consult the O&M Requirements and Guidance Notes for a list of O&M event activities that call for notification to be filed with the CER.

Since 2015, there have been a total of 802 O&M activities reported by the TC Canadian Mainline. When the activity involves an integrity dig, the activity may entail exposing an area of the pipeline by performing one or more integrity assessments. There have been 736 individual integrity digs as part of the reported O&M activities.

These O&M activities can occur anywhere along or near the pipeline right-of-way, including near populated areas. In the past year (2023), O&M activities have occurred most often near North Bay ON, Regina SK, Brampton ON among others.

There have been 8 O&M activities for which new temporary or permanent land is required and is located within critical habitat for any Endangered or Threatened species listed on Schedule 1 of the federal Species at Risk Act. When this happens, the company may be required to meet additional regulatory obligations outside of the CER Act, such as the Migratory Birds Convention Act and the Species at Risk Act.

Dashboard: TC Canadian Mainline - O&M Activites by Year

Province/Territory

Integrity Dig?

In Stream Work Required?

Fish Present?

Species At Risk Present?

Source and description

Data Source: Open Government

Description: The above bar chart displays the number of O&M activities from 2015 to current, arranged based on the starting year of the activity. Each bar is stacked based on several parameters, with the default view showing the province/territory where the O&M activity occurred. Navigation buttons to the right of the bar chart provide the option to view the number of O&M activities by province/territory, if the activity includes an integrity dig, if in-stream work is required, if there are fish present, and if there are species at risk present.

View the requirements and guidance notes (O&M Guidelines) for more information on how these events are regulated while promoting safety, security, environmental protection, economic efficiency, and respect for the rights of those that may be affected.

Section updated: November 2024

Contaminated Sites and Remediation

As part of the CER’s environmental protection activities, we require companies to manage and remediate contamination throughout the lifecycle of the facilities. As a first step, regulated companies are required to report contamination to the CER through the online submission of the Notification of Contamination (NOC).

After the NOC is submitted, companies must demonstrate they are actively managing the contamination according to the Remediation Process Guide. The progress and current status of remediation at the contaminated site are captured in the annual update submitted by a company each year for a contaminated site.

Third party contamination is on-site contamination that is shown to not be emanating or migrating from the company’s facilities or company-owned or leased lands or Right-of-Way. While third-party contamination is not the result of company activities, the CER still requires that this contamination is reported to the CER through the submission of the NOC.

The dashboard below contains information that is contained in the NOC's and annual updates found in REGDOCS. The CER publishes NOCs that have been submitted to the CER since August 2018, when the CER started collecting this information electronically and annual updates that have been submitted since 2021. For information on contaminated sites for which NOCs were submitted prior to August 2018, email remediation@cer-rec.gc.ca.

There are many different methods and approaches to remediate contamination. Thus, when a company submits a plan for remediation (i.e., remedial action plan) for CER review, they are required to include an options analysis to support the remedial method chosen, select appropriate remediation criteria and demonstrate engagement with potentially affected persons, among other requirements. CER analysts also review closure reports submitted by the company once the remediation is completed to ensure remediation has been completed appropriately.

The TC Canadian Mainline has reported a total of 75 contaminated sites since 2011 when the first Remediation Process Guide was first published. There have been 9 contaminated sites reported since August 2018, and information about these contaminated sites is featured in the dashboard below.

Dashboard: TC Canadian Mainline - Contaminated Sites (post Aug 15, 2018)

Bubble size illustrates the approximate site location and does not indicate the size of the contaminated area

Status

Activity at time of discovery

Pipeline or Facility?

Category of Contaminants

The status of remedial activities. Click on a bar to view Status sub definition

Source and description

Data Source: Open Government

Description: The above map displays the approximate location of contaminated sites that have been reported since August 2018. The map defaults to show contaminated sites as bubbles which are coloured based on the year the Notice of Contamination was submitted. Contaminated sites on the map can be re-categorized based on the province/territory, if the site is within 30 metres of a water body, and the applicable land use at the site. The contaminated sites can also be toggled to display a stacked bar chart of events over time by clicking on the contaminated sites trends button above the map. The stacked bars display the number of contaminated sites reported by year. Like the map, contaminated sites can be re-categorized by clicking on the side buttons to view a breakdown of contaminated sites by site status, activity at time of discovery, pipeline or facility, and contaminant type.

Section updated: November 2024

Damage Prevention Regulations Contravention Reports

Damage prevention is where people and pipelines meet; it is the proactive process that keeps people, the environment, and pipelines safe.

The CER takes action to protect Canadians and the environment. Some of these actions include having safety requirements for activities near the pipelines that we regulate. Unauthorized activities on or around pipelines are unsafe and illegal. If pipelines are contacted or damaged, the result could be very serious.

The CER Damage Prevention Regulations (DPRs) outline the obligations of the pipeline companies to have robust damage prevention and public awareness programs that provide people living and working near pipelines the information to ensure those activities near their pipelines are done safely with respect to the pipeline. The DPRs also outline the requirements for people living and working near pipelines to communicate with pipeline companies when they are planning any construction activity (digging, building, driving on the right-of-way) and to follow the instructions that the pipeline company gives them.

Damage prevention is a shared responsibility, and we all play a part in making sure that everyone stays safe when working near a pipeline.

Pipeline companies must immediately report to the CER any activity near their pipelines that does not follow the rules and specifications set out in the DPRs. These violations are called contravention reports. The CER provides an Open Government dataset containing information on each reported contravention. Some summary statistics and a dashboard displaying this data is available below.

From 2019 to 2024, there have been a total of 262 contraventions reported for the TC Canadian Mainline. Of these, 144 have included a ground disturbance, and 8 have caused physical damage to the pipeline such as dent or gouge. A ground disturbance contravention happens when someone digs below 30 cm within the pipelines prescribed area without first getting consent from the pipeline company or when a locate request hasn't been made. These events can be considered as near-miss events that could have led to a more serious pipeline incident.

The CER reviews all contravention reports submitted by regulated companies, and further action may be required of the company. From 2019 to 2024, 8 contraventions have required additional action.

Dashboard: TC Canadian Mainline - DPR Contravention Reports (2019-2024)

DPR Contravention Reports can have multiple Event Type values. Chart totals may appear larger due to double counting.

Event Type

Was Pipe Damaged?

Who Discovered The Event

Method Of Discovery

Source and description

Data Source: Open Government

Description: The above map displays the location of DPR contravention reports that have been reported for the pipeline system over the past five plus years. The map defaults to show DPR contravention reports as bubbles which are coloured based on whether the pipe was damaged. DPR contravention reports on the map can be re-categorized based on whether there was a ground disturbance, the year, and who discovered the event. The DPR contravention reports data can also be toggled to display a stacked bar chart of events over time by clicking on the DPR Contravention Reports Trends button above the map. The stacked bars display the number of DPR contravention reports by year, with bar colour segments corresponding to the event type. Similar to the map, DPR contravention reports can be re-categorized by clicking on the side buttons to view a breakdown of events by whether pipe was damaged, who discovered the event, and method of discovery.

Emergency management

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Section updated: March 2025

The CER checks to make sure companies are keeping pipelines safe by doing inspections, in-depth safety audits, and other activities. Yet, even with these precautions, an emergency could still happen. Sound emergency management practices improve public safety and environmental protection outcomes, and provide for more effective emergency response.

The CER holds its regulated companies responsible for anticipating, preventing, mitigating, and managing emergencies of any size or duration. Each company must have an emergency management program that includes detailed emergency procedures manuals to guide its response in an emergency. We oversee the emergency management program of a regulated company’s project for its entire operation.

The CER requires companies to publish information on their emergency management program and their emergency procedures manuals on their websites so Canadians can access them.

To view TransCanada Mainline’s Emergency Response Plan, go to TransCanada’s Emergency Preparedness website.

Footnotes

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Section updated: October 2024

Footnote

Footnote 1

Pipeline companies regulated by the CER are divided into two groups for financial regulatory purposes. Group 1 consists of those pipeline companies with extensive systems and several third-party shippers. Through the CER’s Filing Manual Guide BB.2 Traffic Data filing requirements, they are required to report capacity and throughput data. Group 2 consists of the remaining pipeline companies that operate smaller, less complex pipelines with few or no third-party shippers. These companies are not subject to the same reporting requirements as Group 1 companies.

Return to footnote 1 referrer

Footnote 2

The ‘CER-regulated pipeline length’ data in this table includes all segments of the pipeline, regardless of operating status and therefore includes segments that are in service, deactivated, decommissioned, or abandoned. The data is determined using information supplied by the companies subject to CER oversight. This data relies on calculations and gets updated periodically to account for new projects, transfers of ownership, or other changes to the pipeline system. Note that the pipeline length may not be consistent with data from other sources that use different methods for their calculations.

Return to footnote 2 referrer

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TransCanada (TC) Canadian Mainline

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Dashboard: TC Canadian Mainline - In Progress Conditions by Region

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Dashboard: TC Canadian Mainline - Incidents with a product release

Operations and Maintenance Activities

Dashboard: TC Canadian Mainline - O&M Activites by Year

Contaminated Sites and Remediation

Dashboard: TC Canadian Mainline - Contaminated Sites (post Aug 15, 2018)

Damage Prevention Regulations Contravention Reports

Dashboard: TC Canadian Mainline - DPR Contravention Reports (2019-2024)

Emergency management

Footnotes