Figure 7: Pipeline occurrences

2009 2010 2011 2012 2013 2014
Reported accidents 15.00 11.00 5.00 7.00 11.00 5.00
Reported incidents (mandatory) 118.00 145.00 167.00 173.00 118.00 133.00
Voluntary reporting 0.00 0.00 5.00 3.00 4.00 1.00

Accident rate

One indicator of pipeline transportation safety in Canada is the pipeline accident rate (Figure 8). According to data provided by the National Energy Board, pipeline activity increased by 6% from 2013. The 2014 rate was 0.3 pipeline accidents per exajoule,5 down from 0.8 in 2013, and down from the annual average of 0.8 in 2009–2013.

Figure 8: Pipeline accident rate

Accidents per exajoule
2005 2006 2007 2008 2009 2010 2011 2012 2013 2014
Accident Rate 0.38 0.68 0.53 0.48 1.20 0.88 0.38 0.52 0.77 0.33
Exajoules are estimated (Source: National Energy Board)

In 2014–2015, no pipeline investigations were started, and one investigation was completed.

Investigations

In 2014–2015, no pipeline investigations were started, and one investigation was completed. The duration of the completed investigation was 665 days, above the average of the previous five years (411 days).

Table 4: Pipeline Investigations at a glance

2009–2010 2010–2011 2011–2012 2012–2013 2013–2014 2014–2015
Investigations started 3 1 0 3 2 0
Investigations completed 1 3 1 0 2 1
Average number
of days to complete
investigations
375 432 404 n/a 402 665
Recommendations 0 0 0 0 0 0
Safety advisories 0 2 1 0 1 0
Safety information letters 0 0 0 2 0 0

Recommendations and progress

No pipeline safety recommendations were issued in 2014–2015. With all of the TSB’s pipeline recommendations rated as Fully Satisfactory, no responses to recommendations were reassessed.

Pipeline highlights

Improved leak-detection technologies (P13H0013)

This year, the TSB released one pipeline investigation report regarding a February 2013 crude oil pipeline leak near Wrigley, Northwest Territories (NWT). The report, published in December 2014, notes that the leak was discovered as part of the industry’s proactive efforts to look for leaks and cracks.

During a planned investigative excavation as part of Enbridge Pipelines Inc.’s Line 21 integrity management program, sheen from crude oil was noticed at kilometre post 391 near Wrigley, NWT. Further examination revealed a crack on the pipe surface near a girth weld.

The TSB’s subsequent investigation determined that the pipeline failure was a result of internal stress corrosion that had likely initiated prior to the pipeline being commissioned in 1985. The investigation also determined that the methanol used as a drying agent at the time of construction had likely produced an internal pipe environment conducive to the initiation and propagation of stress-corrosion cracking.

As part of the safety action taken, Enbridge Pipelines performed a fitness-for-service assessment of Line 21 and conducted an assessment of currently available leak-detection technologies applicable to the pipeline. A plan was submitted to the National Energy Board outlining the implementation timeline of the updated leak-detection technologies into its engineering assessments of Line 21.