Enbridge’s existing mainline system runs along Highway 2 through northern Minnesota. This corridor currently has 6 active pipelines- most of which were put in during the 1960s.  Line 3 was placed in by the Lakehead Pipeline Company in l96l and has experienced significant structural integrity problems.  Latest public estimates by the Enbridge Company indicate over 1,400 integrity anomalies in the pipeline, which spans over 300 miles of northern Minnesota, crossing part of the Red Lake, Leech Lake and Fond du Lac reservations and the l855 and l842 treaty areas.  

Enbridge has gathered extensive integrity data on Line 3 throughout its years of operation. The integrity data shows a high number of integrity anomalies – specifically, corrosion and long seam cracking. Because of its integrity anomalies, Line 3 has experienced a number of failures during its more than 50-year history. As a result, Line 3 requires a high level of integrity monitoring and an extensive on-going integrity dig and repair program to maintain safe operation of the line. For example, approximately 4,000 integrity digs in the United States alone are currently forecasted for Line 3 over the next 15 years to maintain its current level of operation. This would result in year-after-year impacts to landowners and the environment, and may result in repeated impacts to the same landowners and environmental features.

While we have not seen a classification of the level of these anomalies, we know they can developed into ruptures, spills, or leaks.  Enbridge knows this as well, which is why they are proposing to abandon this structurally impaired line in place and build a brand new one.  This abandonment would allow Enbridge to avoid the costs of restoring and remediating the land their pipelines have contaminated.

Enbridge promises to maintain the pipelines in perpetuity, but no one believes this.  Just ask yourself, what infrastructure from 50 years ago is still in existence now without ongoing maintenance?  Nothing last forever. Not pipelines. Not even Enbridge. The Canadian government found that there was a very real risk that pipeline companies would not have money available forever and would eventually stop maintenance with the result that some landowner in the future would be stuck with a decaying pipeline causing drainage, subsidence, erosion, and contamination, and no way to get the oil industry to pay for its mess.

Once a pipeline is designated as abandoned, pipeline owners and operators no longer incur the expense of maintaining easements with expensive mowing and caretaking. And, they no longer have to paint posts and put up new signs to mark the pipeline. All of these responsibilities are expensive and time-consuming.

Another huge bonus for abandoning a pipeline is the reduction of taxes or total elimination of ad valorem, school, county and other jurisdictional levies. Generally speaking, taxes are almost nonexistent for abandoned pipelines. But still, if a landowner wants to claim the pipeline on his or her property, the pipeline company will likely claim it is their property and explain that the pipeline is only “idled” as opposed to a “given up entirely” type of abandonment.

Enbridge is already trying to demand taxes back from counties where their mainline is located- if they are allowed to abandon their pipes in these same countries, where is the guarantee they will be held liable for damages down the road?  In Minnesota, the Department of Commerce does not believe their current plans for “decommissioning” are legal or well thought out.


Line 3 Abandonment Concerns

If Enbridge is not required to remove the pipeline and restore the damaged ecosystems, there may never be a full accounting of the contamination surrounding the pipeline.  This contamination would become the responsibility of nearby landowners.

At the state level, there are no abandonment guidelines or definitions for intrastate gas, liquids, or oil pipelines, and there are no abandonment guidelines or definitions for intrastate oil or gas gathering systems. Any mention of abandonment of pipeline procedures follows federal guidelines of disconnecting from active gas service and purging of any hazardous substance.

PHMSA regulations concern the safety of abandoned pipelines, which the Agency defines as lines that are “permanently removed from service.”  49 C.F.R. Part 192.3; 195.2.  PHMSA regulations prescribe certain steps for the formal abandonment of both oil and gas pipelines, including the disconnection, purging, and sealing of abandoned pipelines left in place.   Parts 192.727(b); 195.402(c)(1).  In addition, operators are required to file an abandonment report for each abandoned facility that is offshore or crosses a navigable waterway, including certification that the facility was abandoned in accordance with all applicable laws.  Parts 192.727(g); 195.59.  Operators must also report the total number of actionable anomalies potentially affecting HCAs that were eliminated by pipe abandonment in the previous calendar year on their annual reports.  PHMSA Forms 7000-1.1; 7100.2-1.

While United States Federal abandonment regulations are sparse, the Canadian National Energy Board (NEB) regulates all aspects of pipeline abandonment, because it found that landowners faced substantial risks from abandoned pipelines.  For example, it regulates surveys of the abandoned pipeline to identify potential contamination, removal, plugging, or filling abandoned pipelines to ensure that they don’t cause drainage problems or sinkholes, and has ordered Enbridge to set aside nearly $1 billion to pay for the future abandonment of its pipelines in Canada.  In the US, the responsibility to protect landowners and the public from the risks created by abandoned pipelines is on the states.

The main risks associated with decommissioning the Existing Line 3 Pipeline in-place: residual contamination, pipeline collapse and ground subsidence, the pipeline acting as a water conduit, and pipeline exposure.   These possible impacts have been documented in decision documents from the National Energy Board of Canada:

Enbridge stated that pipeline exposure may occur as a result of buoyancy forces acting on a pipeline, erosion and slope instability, and scour of overburden at watercourse crossings as a result of natural watercourse dynamics and events such as flooding. It further noted that the exposed pipe is vulnerable to accelerated corrosion and may present a safety hazard or pose a physical barrier to land use, navigation, wildlife movement, and fish migration. Enbridge considered the effects of an exposed Decommissioned Line 3 Pipeline to the environmental elements of fish and fish habitat, wetlands, navigation and navigation safety, and accidents and malfunctions. Enbridge stated that exposed pipe in a watercourse could cause alteration or loss of riparian or instream habitat and result in adverse effects to fish and fish habitat. In addition, Enbridge noted that exposed pipe could alter the bed, shores, and hydrology of a wetland and may negatively affect wetland habitat function. Enbridge stated that there is a high probability that pipeline exposure would occur while the Decommissioned Line 3 Pipeline remains in-place, but predicted that the events would be intermittent and sporadic. It was of the view that any effects to fish and fish habitat or wetlands would be of a low magnitude and reversible in the medium- to long-term since regular inspections would identify any instances of pipe exposure and remedial actions would be applied to rectify the issue. Enbridge’s confidence in predicting the effects was low to moderate based on an understanding of the cause-effect relationship.

Enbridge’s effects assessment also indicated that an exposed Decommissioned Line 3 Pipeline within a navigable waterbody could pose a public safety risk to users of that waterbody. It predicted that the probability is low since it is unlikely that an accident resulting in harm to the navigable waterway user would occur, given that Enbridge plans to conduct depth of cover surveys at a frequency of at least every 10 years, which would identify areas of exposed pipe. Enbridge stated the magnitude of any effects would range from low to high depending upon the severity of the accident. Enbridge assessed the reversibility of any effects to be long-term but noted that once an exposed pipeline is discovered, it would take less than one year to remediate.  Enbridge’s confidence in predicting these effects is low to moderate based on the understanding of the cause-effect relationship.

Abandonment and the Next Seven Generations

Line 3 is the first major crude oil pipeline to be abandonment in Minnesota.  What happens with this line will likely set the stage for future abandonment.  We have seen Enbridge continually try to shirk their responsibilities and hand-off the long-term liabilities of their legacy to the landowners, taxpayers, and residents of Minnesota.  Their current “landowner choice” proposal is an underhanded attempt to avoid a full accounting of the contamination existing in their mainline corridor. They intend to leave their decaying pipeline in place, doing little to nothing to repair the environmental damage of oil infrastructure.

Our concern is what will happen if this pipe is left in the ground for the next seven generations to deal with.  Enbridge has admitted that the longer the pipe Is in the ground, the more likely it is to fail. Failure of an abandoned pipeline generally refers to “through-wall corrosion”- an event that can lead to subsidence, water infiltration, and related issues.  In addition to these issues, once a pipeline is no longer in service, the loss of the weight of the crude can cause the pipeline to rise from the ground due to changes in buoyancy.

Whether subsidence occurs, and the extent to which it occurs depends on the structural integrity of the pipe and on the loads applied to the pipe that could cause it to deform and fail. In general, loads at the pipe level (underground) are less than live loads at the surface (like those from a heavy truck), because part of the load is shared with the surrounding soil. If there is a dearth of surrounding soil, or if the cover for the pipeline is relatively shallow, the pipeline bears more of the load and, all things being equal, is more likely to fail -- There are numerous places where pipes are exposed or have less than an adequate ground cover.   A study of Google Earth shows many exposed areas of pipe, and there are undoubtedly many more areas where the pipe is close to the surface.  

Enbridge has acknowledged that the extensive disbonding of the Line 3 polyethylene tape pipe coating will render cathodic protection ineffective to prevent corrosion and has estimated time to through wall penetration at 25 to 50 years. A study conducted in Canada found that:

"Progressively greater agricultural surface loads increase the potential for pipeline collapse and ground subsidence.  In addition to health and safety concerns and related costs and liabilities, topsoil loss upon ground subsidence will result in permanent long-term production losses."

Enbridge has indicated that impacts on human and natural resources due to potential subsidence of the ground above the abandoned Line 3 are anticipated to be minimal in the near term but could be significant in the longer term

Enbridge estimates the short-term cost of abandoning Line 3 in place to be approximately $85 million. For context, Enbridge estimates annual monitoring costs for Line 3 to be about $100,000. Costs for future site-specific mitigation measures (e.g., to mitigate subsidence or loss of buoyancy control) are uncertain and would depend on the nature of the mitigation measures. Enbridge estimates the cost of removing Line 3 at approximately $1.28 billion. This estimate is based on a per-foot cost for removal at about $855.  If Enbridge was required to do a full remediation and restoration of the line, they could help develop a new industry for Minnesota. the restoration industry creates 10.4 to 39.7 jobs per $1 million invested, in comparison to the oil and gas industry, which produces 5.3 jobs per $1 million invested. Additionally, jobs associated with this sector tend to be better-paying jobs.

For other reviews of Enbridge’s Abandonment Plans, see:





For more information on abandonment see:





For information on case law, Code of Federal Regulation, and other references for this article see



Article about pipeline salvaging:

About pipeline salving industry, with some more information about abandonment laws and ownership.



FERC Overview of Oil Pipeline Regulations:

Very good powerpoint of the regulations over oil pipelines, including comparison to gas pipelines and overview of the Canadian system.



Canadian National Energy Board Abandonment Guideline document:


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