Pollutant spills worldwide – 2015

Sea & shoreline

Number of spills by area

In 2015, Cedre identified 26 spills involving volumes equal to or greater than approximately 10 m3 from its database, for which sufficient information was available for statistical analysis. Almost half of these spills occurred at sea, a quarter in ports, around 20% inshore and approximately 10% in estuaries.

The number of incidents recorded in 2015 is close to the annual median of 29 incidents for the previous decade (2004-2013).

Quantities spilt by area

The total quantity of oil and other hazardous substances spilt, around 13,500 tonnes, is far lower than the median estimated using the same method for the previous 10-year period (around 30,500 tonnes), ranking the 2015 total among the lowest estimates since 2004. Overall, the significant spills in 2015 have a median quantity of around 45 tonnes.

The quantities spilt in 2015 were mainly (just under 60%) released into inshore waters, with the majority of this volume being due to the loss of a barge which ran aground in September in Indonesia (Java). The second largest share (around 40%) of the quantities spilt was in marine waters, largely due to the collision between an oil tanker and a bulk carrier off Singapore in January. Ports and estuaries were affected by relatively low quantities in 2015.

Number of spills by pollutant type

The vast majority of spills (over 90 % of occurrences in 2015) involved oil. In this category, the most commonly spilt products were light refined oil products (34%), followed by unspecified oil (15%), heavy/intermediate refined products (unspecified IFO grades or <380) and heavy refined products (IFO≥380). These are followed by crude oils of unspecified density and, alongside oil products, 2 occurrences in the coal derivatives category.

Quantities spilt by pollutant type

In terms of the quantities spilt, we note the major share of coal derivatives in the 2015 total, mainly due to the cargo of coal released from a barge which ran aground on the Indonesian coast in September 2015. 

The share of oil in the annual total appears to be mainly dominated by crude oils of unspecified density, followed by light refined products (white oils) and heavy to intermediate oils, although the lack of accurate data prevents a more detailed analysis.

Few chemical spills were recorded, with one case in the synthetic chemicals category (spill of approximately 330 tonnes of methyl tert-butyl ether, or MTBE, following an incident in Galveston Bay, Texas, in March 2015) and two spills of bulk solid mineral fertilisers (potash fertiliser in the case of a bulk carrier in Bangladesh, and ammonium nitrate fertiliser in that of a barge which sank in the coastal waters of Costa Rica).

Inland waters

Frequency of spills by source 

As in previous years, pipelines represented the most frequent source (25 %) of significant inland water pollution incidents recorded in 2015, followed by overland transport in tanks, representing a total of 22 % of cases (divided between tank cars and tanker trucks, with respectively 14 % and 8% of the number of spills). Onshore oil facilities were the source of around 20% of spills, in particular oil wells (14%) and refineries (5 %). These were followed by various onshore industrial facilities, with power plants being responsible for 8% of spills and mines 5%. The other types of sources identified in 2015 – vessels (barges) and various facilities (factories, various SMEs, etc.) – were involved in less than 5 % of significant spills during the year.

Quantities spilt by source

In terms of quantities, we note the vast predominance (around 95 %) of mines in the 2015 total. Aside from these mining-related spills, the largest quantities spilt were from land pipelines (50% of total, excluding mines), then vessels (barges, totalling 24%) and overland transport (tanker trucks and tank cars, giving a combined total of 20% of the overall total, excluding mines).

The other sources identified represented only a minor share (less than 3%) of the estimated total for 2015. Given the patchy nature of the data identified, no accurate indication of their relative shares of the overall total can be given, except from stating that they are most likely underestimated. 

Quantities spilt by pollutant type

The 2015 total is very largely dominated (around 94%) by releases of waste waters, in particular containing mineral matter from mining activities (around 71,400 tonnes of waste water mainly containing heavy metals). This is due to two spills of 11,400 and 60,000 tonnes, respectively, which occurred in the United States and in Brazil following the rupture of the walls of waste water retention ponds. 

Aside from these mining effluents, oil represented the highest share (77%) of the total volume spilt, mainly composed of unknown/unspecified oil (around 42%) and crude oil (31%), which would appear to rank far higher than light refined products (whose share may be underestimated due to incomplete data).  

In 2015, the share of chemicals (around 22%) was lower than that of oil. This is however an underestimation, due to the lack of available data on a spill of a synthetic chemical at a paper mill in the US. The major share of this category involved bases (15% of annual total), due to a single spill of around 750 tonnes of caustic soda (when a barge capsized in July 2015 in Louisiana, US), ahead of alcohols (5 %) and acids (2 %).