Why do we need more research on pipeline retirement?

When a pipeline reaches the end of its operating life, it’s retired. That means the pipeline is emptied, scrubbed clean and checked for safety along its entire route, and above ground facilities are removed.

So, even though the term ‘abandoned’ is often used synonymously with ‘retired’, pipeline companies don’t just turn off the tap and walk away.

But you might be surprised to learn that very few transmission pipelines in Canada have been retired to date. Smaller gathering, feeder and distribution lines go out of service more frequently, but when it comes to large diameter transmission lines, we have little experience to tell us what the long-term impacts might be along the right-of-way.

Why landowners are concerned about retired pipelines

Many farmers and other landowners are concerned about what will happen after pipelines on their land are retired. And rightfully so, given that we have definite gaps in our knowledge.

Their biggest concerns centre around the degradation and potential collapse of retired pipelines. Here’s where questions arise:

  • When a pipeline is retired, is the cathodic protection that helps prevent corrosion switched off?
  • How long might it take a retired pipeline to corrode?
  • What will happen on the surface once a pipeline corrodes?

Landowners are also worried that sudden subsidence (settling or sinking) could damage machinery, or even endanger people or livestock. You can read more about their opinions in our ‘Landowner Survey’, conducted in 2011.

Research is helping us anticipate future impacts

Since 2013, CEPA has been sponsoring a Pipeline Abandonment Research Program, in conjunction with the Petroleum Technology Alliance of Canada (PTAC), who administers the program

The goal of the research programis to learn what happens to pipelines after they have been retired, and to develop guidelines for safe, economic and environmentally sound pipeline retirement.

The program’s steering committee includes four representatives from CEPA member companies, a representative from the National Energy Board (NEB), and a representative from each of two landowner groups: L’Union des producteurs agricoles and the Canadian Federation of Agriculture.

What’s being learned

So far, the program has completed several research projects, including:

  1. Understanding the Mechanisms of Corrosion and their Effects on Abandoned Pipelines
  2. Frost Heave Effects on Pipeline Exposure Rates
  3. Decomposition of Pipe Coating Materials in Abandoned Pipelines
  4. Cleaning of Pipelines for Abandonment

As we continue these scientific studies, and learn more about the long-term impacts of pipeline retirement, it equips us to make better informed decisions on abandonment processes. In fact, one of the conclusions of the first study, above, was that projects should be assessed on a case-by-case basis, because variables such as the soil type and the depth of the pipeline can dramatically affect how long it takes a pipeline to corrode, and what happens when it does. More detailed results are available online.

If you’d like to learn more about pipeline retirement, check out these earlier blog posts on the subject: