5 Pressures and impacts on the
5.7.3 Impacts of acute oil pollution and
The impacts of acute oil pollution on the marine environment are many and varied, but the most important can be summarised as follows:
– Drifting oil slicks may contaminate seabirds that are closely associated with the water sur
face when feeding, diving or resting.
– Oil that drifts ashore may contaminate sea
birds and other birds which use the littoral and supra-littoral zone when feeding or resting.
Under particularly unfavourable conditions, oil may affect a considerable proportion of the populations of vulnerable species such as the common guillemot and the Atlantic puffin.
– Oil that drifts on the water surface and on to beaches may contaminate mammals that are closely associated with the sea (for example seals, otters and mink).
– Oil that drifts ashore may foul or smother and cause damage to plants and animals in the lit
toral and supra-littoral zone, and may also pen
etrate deep into the soil and sediments. It will
then leach into the water, causing long-term exposure to oil.
– Oil that drifts ashore may be whipped up by strong winds and foul beaches and salt marshes, where it will smother and have toxic effects on plants and animals that live in and above the spray zone.
– Oil that is dispersed or dissolved in the water masses may have toxic effects on fish (particu
larly eggs and larvae) and planktonic organ
isms and under particularly unfavourable con
ditions may affect a substantial proportion of a year class of fish.
– Oil drifting on the sea and/or that drifts ashore will reduce the recreational value of affected areas for varying lengths of time.
– Oil pollution may result in restricted access to certain areas and restrictions on sales of sea
food for varying lengths of time, and this may have an impact on the fisheries and aquacul
ture industries.
The environmental risk, or the risk that an oil spill will affect seabirds, the supra-littoral zone or other elements of the ecosystem, depends on a number of factors. The most important of these are the probability of an oil spill, the magnitude of a par
ticular spill, its geographical position in relation to vulnerable areas and resources, when it occurs in relation to periods when vulnerability to oil spills is particularly high, and the spill trajectory. The efficiency of the emergency oil spill response sys
tem, which may vary considerably depending on the weather conditions at the time, is another important factor.
5.7.4 Risks associated with maritime transport
The current volume of maritime transport is low in the High North compared with other parts of the Norwegian coast and other parts of Europe.
This means that the probability of accidents and incidents that can lead to oil spills is also lower than in areas further south. However, the environ
mental impact of an accident may be consider
able. Human error is the predominant reason for accidents involving ships. Oil spills from maritime transport may be the result of groundings, colli
sions, structural errors or fire/explosion.
The Norwegian Coastal Administration has carried out more detailed environmental risk anal
yses for maritime transport along the Norwegian coast and in the waters off Svalbard, see figure
Figure 5.12 The risk analysis process for maritime transport
Source: Working group report on managing the risk of acute oil pollution in the Barents Sea–Lofoten area, October 2005
5.12. These analyses reflect the level of environ
mental risk given the current volume of maritime traffic and the projected volume in the future. The risk trend has been analysed for the Barents Sea–
Lofoten area up to 2020. The main elements of the risk analysis process are:
– Traffic analysis and identification of accident frequency and oil spill volumes (oil spill risk) – Oil drift modelling and assessment of possible
spill trajectories for identification of impact areas and the probability that sensitive areas or species will be contaminated by oil
– Vulnerability calculation – calculation of the vulnerability of impact areas based on the vul
nerable environmental resources that are present and using certain assumptions
– Assessment of the impact on selected vulnera
ble environmental resources and aquaculture facilities
– Environmental risk – combination of the calcu
lated vulnerability, accident frequency, proba
bility of pollution and impact weighted accord
ing to spill volume.
International and Norwegian accident statistics have been used in oil spill risk modelling for the Barents Sea–Lofoten area, corrected for the type and age of ships sailing in the area, traffic density, the measures implemented to reduce the proba
bility of accidents and the distinctive features of the area.
A scenario for the traffic situation in 2020 is based on a number of assumptions, including the following:
– 57 million tonnes of petroleum products will be shipped from Russia each year.
– Exports to the USA will increase from 2012 onwards.
– The Stockman field will start production in 2016.
– Petroleum products will be exported from the management plan area.
Figure 5.13 Average recurrence interval for acute oil pollution from maritime transport along the coast of North Norway
Source: Working group report on managing the risk of acute oil pollution in the Barents Sea–Lofoten area, October 2005
– Mandatory routeing and traffic separation schemes will be in operation all along the coast of North Norway from 2007 onwards.
– The vessel traffic service station in Vardø will go into operation in 2007.
– There will be an increase in activity off Sval
bard.
The most important measures to reduce the prob
ability of major oil spills from ships are the intro
duction of a minimum sailing distance from the coast, traffic separation schemes and the estab
lishment of vessel traffic service centres.
Statistics show that ships transporting oil to and from Northwestern Russia along the coast of Norway are generally of a high standard. This is because oil tankers delivering oil in Europe are subject to strict port state control.
According to the risk analysis, the probability of accidental oil spills in both 2003 and 2020 is highest in the southern coastal segments in the area covered by the management plan, while the greatest change in probability from 2003 to 2020 will be in the northern and eastern coastal seg
ments. The recurrence interval, i.e. the expected number of years between each accident per 100 nautical miles of coastline, is estimated to be 11 years for the entire management plan area in 2003. This includes all types and sizes of oil spills from all types of vessels of gross tonnage over 5000, see figure 5.13.
Oil and gas tankers will account for most of the increase in traffic between now and 2020. Rus
sian exports of crude oil pose the greatest risk of
Figure 5.14 Probability of oil spills from maritime transport in the Barents Sea in 2003 and 2020, by size categories
Source: Working group report on managing the risk of acute oil pollution in the Barents Sea–Lofoten area, October 2005
oil spills. The probability of oil spills may increase somewhat throughout the management plan area during the period and give a shorter recurrence interval than 11 years. However, the requirement of a minimum sailing distance from the coast for loaded oil tankers and other risk-reducing measu
res that are to be implemented will considerably reduce the probability of major oil spills (>100 000 tonnes) from ships from 2003 to 2020.
Thus, despite the higher volume of traffic in 2020, the risk of oil spills will be more than halved as a result of the measures that will be imple
mented between 2003 and 2020. The most impor
tant of these are the minimum sailing distance from the coast, traffic separation schemes and the establishment of vessel traffic service centres.
Other factors that influence environmental risk are the position of the ship, the environmen
tal value of the affected areas and the time of year when the oil spill occurs.
The analysis indicates that environmental impacts in 2020 will be similar to those in 2003.
Compared with the risk in coastal areas further south, the overall environmental risk throughout the Barents Sea–Lofoten area can therefore still be characterised as low in 2020, and the level will be similar to that in 2003.
However, just as is the case for petroleum activities, accidents cannot be ruled out and the impacts of oil spills from maritime transport may be considerable, see section 5.7.3.
Shipping in Svalbard’s waters can be split into three categories: 1) fishing vessels, 2) transport to and from mining operations and 3) cruise ships. The predominant category is fishing ves
sels. They generally carry only small amounts of
bunker oil on board and the environmental risk they pose is limited. Transport associated with Norwegian mining operations is strictly regu
lated, and the probability of oil spills is regarded as small. Other commercial traffic to the settle
ments in Svalbard is more limited. An oil spill is most likely to be caused by the grounding of a large cruise ship and the subsequent release of bunker oil. The calculated frequency is low, but given the major impact of such an incident the environmental risk is set at medium to high. The conditions on Svalbard will make oil spill response and clean-up operations difficult.
An oil spill resulting from a grounding in the approach to the Svea mine could also cause consi
derable damage to the environment, but is consi
dered to be very unlikely, given the measures that have been implemented.
In the light of the emergency response situa
tion in Svalbard, an interministerial working group has recommended regulating the type of bunker oil that ships may carry on board around Svalbard. This would reduce the risk of large spills of heavy bunker oil in the event of an emer
gency. It would also considerably reduce the envi
ronmental risk associated with maritime transport in this area. It has been suggested that this requirement should apply in the large protected areas established from 1973 onwards, and which now include most of Svalbard’s territorial waters.
It will be necessary to evaluate which exemp
tions should be made for commercial transport to and from the settlements in Svalbard and whether fishing vessels should be exempt from the requirement, given the small amounts of bunker oil they carry. An assessment must also be made of whether cruise traffic to established destina
tions should be exempt from the requirement.
Shipping in the areas that are exempt from the requirement should follow specific traffic lanes/
zones where navigational aids will be upgraded.
5.7.5 Risk associated with petroleum