European oil industry group CONCAWE has collected 40 years
of spillage data on European cross-country oil pipelines with
particular regard to spillages volume, cleanup and recovery,
environmental consequences and causes of the incidents. The
results have been published in annual reports since 1971.
CONCAWE recently issued a report that covers the performance of
these pipelines in 2010 and provides a full historical
perspective since 1971. The performance over the whole 40-year
period is analyzed in various ways, including gross and net
spillage volumes. Spillage causes are grouped into five main
categories: mechanical failure, operational, corrosion, natural
hazard and third party.
Data for the CONCAWE annual survey comes from 77 companies
and agencies operating oil pipelines in Europe. For 2010, data
was received from 69 operators representing over 160 pipeline
systems and a combined length of 34,645 km (Fig. 3), slightly
less than the 2009 inventory. There were minor corrections to
the reported data.
Fig. 3. CONCAWE oil
pipeline inventory and
main service categories from
Nine operators did not report, but CONCAWE believes none of
them suffered a spill in 2010. Nevertheless, they are not
included in the statistics. The reported volume transported in
2010 was just under 800 million m3 of crude oil and
refined products, about 10% less than in 2009. Four spillage
incidents were reported in 2010, corresponding to 0.12
spillages per 1,000 km of line, well below both the 5-year
average of 0.25 and the long-term running average of 0.52,
which has been steadily decreasing over the years from a value
of 1.2 in the mid-1970s (Fig. 4). There were no reported fires,
fatalities or injuries connected with these spills. The gross
spillage volume was low at 336 m3 (Fig. 5). This is
10 m3 per 1,000 km of pipeline compared to the
long-term average of 78 m3 per 1,000 km of pipeline.
CONCAWE reports that essentially all the spilled volume was
recovered or safely disposed.
Fig. 4. The 40-year
trend for the annual
number of spillages for all pipelines.
Fig. 5. The 40-year
average gross spillage
volume listed per event by cause.
Two of the spills accounted for about 95% of the gross spill
volume. Over the long term, less than 20% of the spillages are
responsible for about 80% of the gross volume spilled (Fig. 6).
Pipelines carrying hot oils such as fuel oil have in the past
suffered from external corrosion due to design and construction problems. Most have
been shut down or switched to cold service (Fig. 7), so that
the great majority of pipelines now carry unheated petroleum
products and crude oil. Only 159 km of hot oil pipelines are
reported to be in service today. The last reported spill from a
hot oil pipeline was in 2002.
Fig. 6. Gross spillage
volume from 19712010.
Fig. 7. Cold pipelines
spillage by cause.
Of the four reported incidents in 2010, two were related to
mechanical failures, one was caused by external corrosion, and
one was the result of third party activities. Over the long
term, third party activities remain the main cause of spillage
incidents, although the number of events has progressively
decreased over the years. Mechanical failure is the second
largest cause of spillage. After great progress during the
first 20 years, the frequency of mechanical failures has been
on an upward trend over the last decade.
In-line inspections were at a record high in 2010. A total
of 89 sections covering a total of 12,300 km (45% more than in
2009) were inspected by at least one type of intelligence
pipeline inspection gauge (pig). Most inspection programs
involved the running of more than one type of pig in the same
section, so that the total actual length inspected was less at
7,178 km (21% of the inventory).
Most pipeline systems were built in the 1960s and 1970s.
Whereas, in 1971, 70% of the inventory was 10 years old or
less, by 2010 only 4.4% was 10 years old or less and 50% was
over 40 years old. However, this has not led to an increase in
spillages. Overall, there is no evidence that the aging of the
pipeline system implies a greater risk of spillage. The
development and use of new techniques, such as internal
inspection with intelligence pigs, hold out the prospect that
pipelines can continue reliable operations for the foreseeable