The data held includes the type of oil spilt, the spill .... relatively low and detailed statistical analysis is .... to
JANUARY 2015
THE INTERNATIONAL TANKER OWNERS POLLUTION FEDERATION LIMITED
OIL TANKER SPILL STATISTICS 2014
Background
I
TOPF maintains a database of oil spills from tankers, combined carriers and barges. This contains information on accidental spillages since 1970, except those resulting from acts of war. The data held includes the type of oil spilt, the spill amount, the cause and location of the incident and the vessel involved. For historical reasons, spills are generally categorised by size, 700 tonnes (5,000 bbls), although the actual amount spilt is also recorded. Information is now held on nearly 10,000 incidents, the vast majority of which (81%) fall into the smallest category i.e. 700 tonnes) as a percentage of those recorded from 1970 to 2009 per decade
OIL TANKER SPILL STATISTICS 03
Number of Oil Spills
T
he incidence of large spills (>700 tonnes) is relatively low and detailed statistical analysis is rarely possible, consequently emphasis is placed on identifying trends. Thus, it is apparent from Table 2 that the number of large spills has decreased significantly in the last 45 years during which records have been kept. The average number of major spills for the decade 2000–2009 is 3.4, one seventh of the average for years in the 1970s. Looking at this downward trend from another perspective, 54% of the large spills recorded occurred in the 1970s, and this percentage has decreased each decade to 8% in the 2000s (Figure 2). A decline can also be observed with medium sized spills (7–700 tonnes) in Figure 4 and Table 2. Here, the average number of spills in the 2000s was close to 15, whereas in the 1990s the average number of spills was almost double this number. We have recorded one large spill for 2014; in January a small tanker sank in the South China Sea loaded with a cargo of approximately 3,000 tonnes of bitumen. Four medium spills of various oils, including crude oil, Year
7–700 Tonnes
>700 Tonnes
1970 1971 1972 1973 1974 1975 1976 1977 1978 1979
7 18 48 28 90 96 67 70 59 60
29 14 27 31 27 20 26 16 23 32
Total
543
245
Average
54.3
24.5
Year
7–700 Tonnes
>700 Tonnes
1980 1981 1982 1983 1984 1985 1986 1987 1988 1989
52 54 46 52 26 33 27 27 11 32
13 7 4 13 8 8 7 11 10 13
Total
360
94
Average
36
9.4
Table 2: Annual number of oil spills (7 tonnes and over)
04 OIL TANKER SPILL STATISTICS
have also been recorded, totalling five spills of 7 tonnes and over. This figure is still far below the averages for previous decades and is in line with the trend of the last four years (Figure 3 and Table 2). We have also recorded several incidents involving fires and explosions onboard tankers with potentially large and medium sized quantities of cargoes and bunker fuel burned. It has not been possible to determine the exact quantities burned, and so they have not been included in our final numbers of spills for 2014. However, the cargoes involved included condensate, diesels and fuel oils. These incidents illustrate the unpredictability of spills and the importance of preparing to respond to the range of oils that can be spilt. Year
7–700 Tonnes
>700 Tonnes
1990 1991 1992 1993 1994 1995 1996 1997 1998 1999
50 30 31 31 26 20 20 28 25 20
14 7 10 11 9 3 3 10 5 5
Total
281
77
Average
28.1
7.7
Year
7–700 Tonnes
>700 Tonnes
2000 2001 2002 2003 2004 2005 2006 2007 2008 2009
21 18 11 18 19 21 11 12 7 7
4 3 3 4 5 4 5 3 1 2
Total
145
34
Average
14.5
3.4
Year
7–700 Tonnes
>700 Tonnes
2010 2011 2012 2013 2014
5 5 7 5 4
4 1 0 3 1
Total
26
9
Average
5.2
1.8
1970-79: 24.5 spills per year on average
35
30 1980-89: 9.4 spills per year on average
Number of Spills
25
1990-99: 7.7 spills per year on average
20
2000-09: 3.4 spills per year on average
15
2010-14: 1.8 spills per year on average
10
5
0
1970
1974
1978
1982
1986
1990
1994
1998
2002
2006
2010
2014
Figure 3: Number of large spills (>700 tonnes) from 1970 to 2014
600 7-700 Tonnes 500
>700 Tonnes
Number of Spills
400
300
200
100
0
1970s
1980s
1990s
2000s
2010s
Figure 4: Number of medium (7–700 tonnes) and large (> 700 tonnes) spills per decade from 1970 to 2014* * Only 5 years of data for the period 2010–2014
OIL TANKER SPILL STATISTICS 05
Quantities of Oil Spilt
T
he vast majority of spills are small (i.e. less than 7 tonnes) and data on the numbers of incidents and quantity of oil spilt is incomplete due to the inconsistent reporting of smaller incidents worldwide. Reports on spills of 7 tonnes and above tend to be more reliable and information from these is included in the database to give a series of annual estimates of the total quantity spilt for the years 1970–2014. These quantities are rounded to the nearest thousand. Inconsistencies may occur between the sums of each year and the totals. However, all percentages and averages have been calculated using unrounded figures. Approximately 5.74 million tonnes of oil were lost as a result of tanker incidents from 1970 to 2014. However, as Figures 5 and 6 indicate, the volume of oil spilt from tankers demonstrates a significant reduction through the decades. Consistent with the reduction in the number of oil spills from tankers, the volume of oil spilt also shows a marked decrease. For instance, from Table 3 it is interesting to observe that an amount greater than
Year
Quantity (Tonnes)
Year
1990 1991 1992 1993 1994 1995 1996 1997 1998 1999
1970s 1970's 56% 56%
1990s 1990's 19.8% 19.8%
the total quantity of oil spilt in the decade 2000 to 2009 (208,000 tonnes) was spilt in several single years in earlier decades. The total recorded amount of oil lost to the environment in 2014 was approximately 4,000 tonnes, the vast majority of which can be attributed to the one large spill (>700 tonnes) recorded in January in the South China Sea (Table 3 and Figure 6).
Quantity (Tonnes) 61,000 431,000 167,000 140,000 130,000 12,000 80,000 72,000 13,000 28,000
386,000 144,000 313,000 159,000 173,000 351,000 364,000 276,000 393,000 636,000
Total
3,195,000
Total
1,133,000
Year
Quantity (Tonnes)
Year
Quantity (Tonnes)
206,000 48,000 12,000 384,000 29,000 85,000 19,000 38,000 190,000 164,000
Total
1,174,000
06 OIL TANKER SPILL STATISTICS
2000 2001 2002 2003 2004 2005 2006 2007 2008 2009
Total
2000s 2000's 3.6% 3.6%
Figure 5: Oil spilt per decade as a percentage of the total spilt between 1970 and 2009
1970 1971 1972 1973 1974 1975 1976 1977 1978 1979
1980 1981 1982 1983 1984 1985 1986 1987 1988 1989
1980s 1980's 20.6% 20.6%
Year
Quantity (Tonnes)
2010 2011 2012 2013 2014
12,000 2,000 1,000 7,000 4,000
Total
26,000
14,000 9,000 66,000 43,000 16,000 18,000 22,000 15,000 2,000 3,000 208,000
Table 3: Annual quantity of oil spilt
700 ATLANTIC EMPRESS 287,000 Tonnes
600
ABT SUMMER 260,000 Tonnes CASTILLO DE BELLVER 252,000 Tonnes
Thousand Tonnes
500 KHARK 5 70,000 Tonnes
400 300
SEA EMPRESS 72,000 Tonnes PRESTIGE 63,000 Tonnes
EXXON VALDEZ 37,000 Tonnes
ERIKA 20,000 Tonnes
200
HEBEI SPIRIT 11,000 Tonnes
100 0
1970
1974
1978
1982
1986
1990
1994
1998
2002
2006
2010
2014
Figure 6: Quantities of oil spilt 7 tonnes and over (rounded to nearest thousand), 1970 to 2014
Large Spills
A
s demonstrated in Figures 6 and 7, when looking at the frequency and quantities of oil spilt, it should be noted that a few very large spills are responsible for a high percentage of oil spilt. For example, in more recent decades the following can be seen: • In the 1990s there were 358 spills of 7 tonnes and over, resulting in 1,133,000 tonnes of oil lost; 73% of this amount was spilt in just 10 incidents. • In the 2000s there were 179 spills of 7 tonnes and over, resulting in 208,000 tonnes of oil lost; 55% of this
amount was spilt in just 4 incidents. • In the five year period 2010–2014 there have been 35 spills of 7 tonnes and over, resulting in 26,000 tonnes of oil lost; almost 90% of this amount was spilt in just 9 incidents. Over the last two and a half decades, the average number of spills greater than 7 tonnes has progressively reduced by half. In terms of the volume of oil spilt the figures for a particular year may be severely distorted by a single large incident. This is clearly illustrated by incidents such as ATLANTIC EMPRESS (1979), 287,000 tonnes spilt; CASTILLO DE BELLVER (1983), 252,000 tonnes spilt and ABT SUMMER (1991), 260,000 tonnes spilt (Figure 6).
3.5
Million Tonnes of Oil Spilt
3
2.5
43% from 14 incidents
2
1.5
1
57% from 774 incidents
65% from 8 incidents
55% from 4 incidents 73% from 10 incidents
45% from 175 incidents
0.5
0
1970s
35% from 446 incidents
27% from 348 incidents
1980s
1990s
2000s
Figure 7: Spills 7 tonnes and over per decade showing the influence of a relatively small number of comparatively large spills on the overall figure
OIL TANKER SPILL STATISTICS 07
Seaborne Oil Trade
A
part from a fall in the early 1980s during the worldwide economic recession, seaborne oil trade has grown steadily from 1970 (Figure 8). While increased movements
might imply increased risk, it is encouraging to observe however that downward trends in oil spills continue despite an overall increase in oil trading over the period.
Billion Tonne-Miles
No. of spills 7 tonnes and over
12,000
140
10,000
120 100
8,000
80
6,000
60
4,000
40
2,000 0
20 1970
1975
1980
1985
1990
Seaborne oil trade (Billion Tonne-Miles)
1995
2000
2005
2010
0
No. of spills 7 tonnes and over
[Source: Fearnresearch 1970-1989, Lloyds List Intelligence 1990-2013]
Figure 8: Seaborne oil trade and number of tanker spills 7 tonnes and over, 1970 to 2013 (Crude and Oil Product *)
Causes of Spills
T
he causes and circumstances of oil spills are varied, but can have a significant effect on the final quantity spilt. The following analysis explores the incidence of spills of different sizes in terms of the operation that the vessel was undertaking at the time of the incident and the primary cause of the spill. For small and medium sized spills, operations have been grouped into Loading/ Discharging, Bunkering, Other Operations and Unknown Operations. Other Operations includes activities such as ballasting, de-ballasting, tank cleaning and when the vessel is underway. Reporting of larger spills tends to provide more information and greater accuracy, which has allowed further breakdown of vessel operations. Therefore, operations for larger spills have been grouped into Loading/Discharging, Bunkering, At Anchor (Inland/ Restricted waters), At Anchor (Open water), Underway (Open water), Underway (Inland/Restricted waters), Other Operations and Unknown Operations. The primary causes have been designated to Allisions/ Collisions, Groundings, Hull Failures, Equipment Failures, Fire and Explosion, and Other/Unknown. Other causes include events such as heavy weather damage and human error. Spills where the relevant information is not available have been designated as Unknown. Small and medium sized spills account for 95% of all the incidents recorded; a large percentage of these spills, 40% and 29% respectively, occurred during 08 OIL TANKER SPILL STATISTICS
* Product vessels of 60,000 DWT and above. Barges excluded.
loading and discharging operations which normally take place in ports and oil terminals (Figures 9 and 12). While the cause of these spills is largely unknown it can be seen that equipment and hull failures account for approximately 46% of these incidents for both size categories (Figures 11 and 14). Nevertheless, when considering Other Operations there is a significant difference in the percentage of allisions, collisions and groundings between these two size groups where we see the percentage increasing from 2% for smaller spills to 45% for medium spills (Figures 11 and 14). Large spills account for the remaining 5% of all the incidents recorded and the occurrence of these incidents has significantly decreased over the past 45 years. From Figure 15, it can be seen that 50% of large spills occurred while the vessels were underway in open water; allisions, collisions and groundings accounted for 59% of the causes for these spills (Figure 17). These same causes account for an even higher percentage of incidents when the vessel was underway in inland or restricted waters, being linked to some 99% of spills. Restricted waters include incidents that occurred in ports and harbours. Perhaps unsurprisingly, activities during loading or discharging result in significantly more small or medium sized spills than large spills. However, large spills do still occur during loading and discharging, and from Figure 17 and Table 6, it can be seen that 57% of these incidents are caused by fires, explosions and equipment failures.
LOADING/ DISCHARGING 40%
UNKNOWN 36%
OTHER/UNKNOWN 64%
ALLISION/COLLISION 2%
FIRE/EXPLOSION 2%
GROUNDING 3%
OTHER OPERATIONS 17%
HULL FAILURE 7%
EQUIPMENT FAILURE 21%
BUNKERING 7%
Figure 9: Incidence of spills