Market Snapshot: Impacts of Enbridge’s BC Pipeline rupture on natural gas flows

Release date: 2019-01-23

On 9 October 2018, a section on Enbridge’s T-South natural gas transmission pipeline (BC Pipeline or Westcoast system) ruptured near Prince George, B.C.^Footnote 1 BC Pipeline supplies natural gas from northeast B.C. to B.C.’s Lower Mainland and the U.S. Pacific Northwest (Figure 1). As a result, daily natural gas deliveries to points south of Prince George decreased 90%, from 1 290 million cubic feet (MMcf) on October 8 to 129 MMcf on October 10 (Figure 2, left-hand side).^Footnote 2 In response, more natural gas flowed along FortisBC’s Southern Crossing pipeline (Figure 2, right-hand side). Gas flows on Southern Crossing approximately doubled after the BC Pipeline rupture, though these volumes were too small to replace the significant decreases resulting from the rupture.

Figure 1: Map of pipelines and points related to the rupture

Figure 2: Daily natural gas receipts and deliveries to the B.C. Lower Mainland from BC Pipeline and Southern Crossing pipeline (August to December 2018)

The affected section of the BC Pipeline near Prince George (Figure 1) has two pipelines – a 30 inch mainline and a 36 inch loop.^Footnote 3 Both lines were shut down when the 36 inch pipe ruptured. Following an evaluation of the line, the National Energy Board (NEB) allowed Enbridge to resume flowing gas on the 30 inch mainline on October 10. Over the course of several weeks, deliveries significantly increased after additional assessments supported safely increasing pressure on certain pipeline segments. By December, volumes increased to approximately 1 400 MMcf per day (December volumes typically average around 1 700 MMcf per day). The majority of the 36 inch loop is flowing gas under restricted pressure, and it will return to maximum operating pressure after the NEB concludes it is safe to do so.

The Southern Crossing pipeline carries a relatively small amount of natural gas into southern British Columbia from NGTL’s Alberta System. It can transport about 100 MMcf per day of natural gas westbound through southern B.C. In addition, FortisBC dispatched trucks carrying compressed natural gas into the Lower Mainland during December. Restrictions originally placed on industrial and commercial consumers to curtail natural gas consumption were lifted. However, according to FortisBC, until Enbridge’s transmission pipeline is operating at full pressure, customers should still be mindful of their energy use.

Date modified:

2023-11-28