Since 1971, Concawe has been collecting spillage data on European cross country oil pipelines with particular regard to spillage volume, clean-up and recovery, environmental consequences and causes of the incidents, and the results have been published in annual reports. Concawe’s Oil Pipelines Management Group’s Special Task Force on oil pipeline spillages has recently published the latest of these surveys, covering the performance of its pipelines in 2015, and again providing a full historical perspective going back to 1971.
The performance over the whole 45-year period is analysed in various ways, and the spillage causes grouped into five main categories: mechanical failure, operational, corrosion, natural hazard, and third-party. The rate of intelligent pig inspections is also reported. This comprehensive annual survey of European oil and products pipelines includes anonymised data from 77 companies and agencies, between them operating 37,403 km of pipelines in Europe. Concawe reports that, for the current survey, 63 operators provided information, representing over 141 pipeline systems with a combined length of 33,903 km.
The volume transported in 2015 was 760 million m3 (418 million m3 of crude oil and 342 million m3 of refined products), the greatest amount for the last few years.
For the year in question, 93 spillage incidents were recorded, a breathtaking total of 87 of which related to theft attempts (either successful or unsuccessful, and classified as ‘third-party intentional’). The comparable figure for 2014 was 54. In a further comparison, there were 28 theft attempts recorded between 1971 and 2012 and, as Concawe points out, the 159 incidents in the last three reporting years signals the emergence of a whole new phenomenon.
The balance of six spillage incidents was split between three relating to mechanical causes (construction for one, and design and materials for the other two) and three due to corrosion (two external and one internal). The total of six spillages corresponds to 0.17 spillages per 1,000 km of line, equal to the five-year average and well below the long-term running average of 0.47, which has been steadily decreasing over the years from a value of 1.1 in the mid-1970s. There were no reported fires, fatalities, or injuries connected with these spills.
Over the long term, third-party activities remain the main cause of spillage incidents (although in 2015 all were due to theft attempts, rather than unauthorised construction activities, etc.). Mechanical failure is the second largest cause of spillage: after great progress during 1971-1991, the frequency of mechanical failures appears to be on a slightly upward trend over the last decade, although this trend has been reversed in the last five years.
When excluding theft events (for which the volume lost is impossible to determine in most cases), the gross spillage volume was 61 m3, or 1.7 m3 per 1,000 km of pipeline, compared to the long-term average of 67 m3 per 1,000 km of pipeline. Sixty nine per cent of that volume was recovered.
Among the companies’ inventory covered by this report, only 45 km of hot oil pipelines are reported to be in service currently, and the last reported spill from a hot oil pipeline was in 2002.
In 2015, 15,394 km of pipeline in 82 sections was inspected by at least one type of intelligent pig. As most inspection programs involved the running of more than one type of pig in the same section, the total actual length inspected was less, at 8,487 km (24 per cent of the inventory, which nevertheless is the highest figure recorded thus far). Most pipeline systems involved in this survey were built in the 1960s and 1970s.
Consequently, when the reporting first began in 1971, 70 per cent of the pipelines in the inventory were 10 years old or less. By 2015, less than 5 per cent were 10 years old or less and 64 per cent were over 40 years old. However, this has not led to an increase in spillages (excluding theft-related events).
Overall, based on the Concawe incident database and reports, there is no evidence to suggest that the ageing of a pipeline system implies a greater risk of spillage.
Concawe’s pipeline statistics, will continue to be used to monitor performance, and form an invaluable record of the pipeline industry’s success. The data included in this continuing analysis can surely be used to counteract uninformed opinion about pipeline safety, and the statistics once again confirm that pipelines are the safest and most environmentally friendly form of liquid energy transportation over long distances.