Oil Tanker Spills: An FAQ


What are oil tankers?

Oil tankers are ocean vessels that transport petroleum oil (10). Petroleum is a liquid mixture composed of hydrocarbons and is mainly used to produce gasoline (10). Tankers can transport crude oil from oil extraction sites, such as tar sands, to refineries (11). Alternatively, they can transport refined oil from refineries to consumers (11).
How do oil tanker spills happen?

Oil spills from tankers in the ocean occur mainly from loading and discharging oil, equipment and hull failures, collisions, fires, or explosions (12). Since the 1970’s, there have been significant improvements in tanker safety and the frequency of oil spills has drastically decreased globally, due to regulations enacted by governments, international organizations and shipping companies (1). The current concern with oil tankers is having effective emergency spill response and spill prevention (1).

How prevalent are oil tanker spills?

Since 1970, there have been approximately 1350 medium-scale oil spills (7 to 700 tonnes) and 455 large-scale spills (more than 700 tonnes) recorded worldwide (12). This does not account for many other small spills that did not get reported (12). Among these events, tankers have cumulatively split at least 5.75 million tonnes of oil across the globe since 1970 (12).

What are the ecological and environmental impacts of spills?

When oil spills into the ocean, oil is broken up into droplets by waves (7). Oil on the ocean surface washes onto beaches and can have devastating impacts on birds (7). When high concentrations of oil accumulate on bird feathers, it inhibits their insulation and can cause hypothermia (7). Further, oil is toxic to many organisms in tidal zones and the droplets can trap smaller organisms (7). When ingested in high concentrations, oil can kill or harm fish and other marine creatures, and can block their gills, preventing respiration (7).

In addition, oil spills have killed many algae-feeders such as sea snails, leading to massive algae blooms (7). It took a long time for algae-feeders to increase in population size and these ecosystems remained out of balance for long periods (7). The space taken up by algae also invaded the habitats of many microorganisms (7). A spill as small as five tonnes of oil that calmed ocean waves attracted a population of 60,000 ducks and devastated the entire population (7).

Oil spills also have especially damaging effects on coral reefs (7). Oil kills coral as well as microorganisms that work symbiotically with coral, and dead coral breaks off and abrasively damages beaches (7). Coral is a threatened species and can take a long time to be reestablished (7). In addition, water-dwelling worms that play an important role in overturning ocean sediment can also die, leading to underwater landslides (7).

One of the largest oil spills in the world that occurred in Alaska in 1989, from the Exxon Valdez tanker, killed thousands of otters and hundreds of seals by causing hypothermia and irritation (7). This accident spilled 37,000 tonnes of oil (7). Oil has also smothered the eggs of endangered sea turtle species in the tropics (7). It can take years for ecosystems to recover and reestablish their balance (7).

How do oil spills impact humans?

Oil spills impact the oil economy when oil is wasted, and also response and cleanup costs impact oil corporations (5). Further, spills are detrimental to ocean industries such as fishing (5).

How are oil spills cleaned up?

Bioremediation is a natural cleanup process in which microorganisms break down biodegradable components of oil, which can be enhanced by the addition of nutrients (14). Oil spills can be cleaned up using physical cleanup methods or by using chemical agents (10). Physical methods include containment booms, or fence-like structures, that keep the oil from spreading (10). Vessels called skimmers can also be used to skim oil off the ocean surface (10). Further, sorbents, or oil-absorbing materials can be used, as well as the use of pumps (10). Chemical agents such as dispersants are also used, which help to disperse the oil into droplets so that it is less concentrated (10).

What is the world doing to deal with oil spill risk?

The International Maritime Organization (IMO) is a United Nations organization committed to the prevention of marine pollution and shipping safety (13).
Since 1993, a law was passed so that new tankers must be constructed with a double-hull, in which the ship has two layers of watertight hull (2). In double-hulls, a steel tank is contained within an outer hull (2). The IMO implemented a policy to phase out of using single-hull tankers and implemented a phase-in period for double-hull tankers (11). The phase-in period of double-hull tankers will be complete worldwide by 2015 (11).

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What are the potential risks of oil spills in Canada?

Canada’s three coasts cover 243,000 kilometers and there are 80 million tonnes of oil shipped from Canada annually (13). There are approximately 1500 tankers moving along the West Coast and around 3000 tankers on the East Coast per year (13). With three coasts lining Canada and heavy annual tanker traffic, there is high potential for accidents to occur. (13)

How prevalent are spills in Canada?

The only major tanker spill in Canadian waters was the spill of the American Odyssey in 1988 near Nova Scotia, in which 132,000 tonnes of oil were spilled (7). Since then, there have been significant declines in spills due to the introduction of double-hull tankers and GPS (7). Despite the rare occurrence of spills, there is still a risk of spills and the potential impacts have serious consequences. Thus, it is important that there are effective contingency plans and prevention plans, and the precautionary principle should be used to avoid negative impacts.

What are the potential economic impacts of tanker spills in Canada?

A recent study at UBC predicted that the cost of a high impact oil tanker spill on the coast of Northern British Columbia from the Enbridge Northern Gateway could cost 9.6 billion Canadian dollars in cleanup and response costs (5). This would lead to high unemployment and loss of all GDP from the Enbridge project, and would also have damaging impacts on other ocean industries such as fishing (5).

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What are the policies for responding to tanker spills in Canada?

Transport Canada, a Federal Government organization, works to prevent spills and follows Canadian and international oil transport regulations (9). Canada’s Marine Oil Spill Preparedness and Response Regime is regulated by Transport Canada and works towards ensuring that potential polluting vessels pay for spill preparation, that polluters pay the costs for response and cleanup, and that strong contingency plans are made (9). The regime is equipped to handle up to 10,000 tonnes of oil spilled in Canadian waters (9).

The spill response procedure for Canada begins with reporting accidents to the Canadian Coast Guard, and then appointing a commander to lead the procedure (9). Next, a cleanup response organization would arrive at the spill site under supervision of the Coast Guard (9). Further, the Regional Environmental Emergency Team would send scientists to advise the best cleanup method (9). Then, the polluter would pay compensation for response costs (9). All of these steps fall under the Canada Shipping Act 2001, an act that governs safety in marine transportation and protects the environment for Canadian waters (9). In Eastern Canada, the Atlantic Accord requires that all oil tankers have a spill contingency plan and that all spills are reported (4).

What measures are there to prevent tanker spills in Canada?

Every year, the Port State Control program does legal inspections of ships entering Canadian ports and ensures that they meet safety standards and stops unsafe ships from proceeding or fixes any inadequacies (11). This includes inspection of structure, watertight conditions and pollution prevention measures (11).

Under the Canada Shipping Act 2001, tankers are required to meet collision prevention standards such as traffic regulations and proper navigation and communication technology (11). Canada also has Vessel Traffic Service Zones, in which ships carrying over 500 tonnes must check in with officers to inspect their safety, navigation and pollutants they may be carrying (11).

Tankers are also inspected to ensure there are no single-hull tankers in Canadian waters (4). Additionally, the Arctic Waters Pollution Prevention Act is in place to prevent pollution of the Canadian Arctic waters by ensuring effective navigation and communication (11).

What recent updates have been made for tanker safety in Canada?

As of March 2013, the Canadian Federal Government proposed amendments to the Canada Shipping Act 2001 to create a “world-class tanker safety system” for oil shipping (16). The government proposed to increase the number of tanker inspections, to increase the number of aerial surveillance planes over coasts, to create a system for more effective spill responses, to increase the number of ports for traffic control, to increase research on impacts of oil products, to add obstacle warnings to navigation routes, and to upgrade the navigation system (16).

Are there protected areas on Canada’s coasts?

There is a Voluntary Tanker Exclusion Zone, a voluntary regulation that prevents tankers travelling from Washington to Alaska from entering the BC coast (11). However, tankers entering and leaving Canadian ports can still travel in this zone (11). Additionally, there is a policy that prevents tankers weighing over 40,000 tonnes from travelling in the West Coast inside passage (11). However, this policy still allows lighter tankers to pass through (11).

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Why are double-hull tankers inadequate?

Although double-hulls are a design measure that helps prevent spills by containing oil leaks, they do not reduce the risk of fires, explosions and collisions (2). Humans run tankers, thus there is always the possibility of human error.

Why are voluntary regulations inadequate?

Regulations on the prevention of oil spills have been made by government policy and by voluntary corporate social responsibility of ship companies (6). It is unclear whether corporate social responsibility has aided in the prevention of oil spills, however there is strong evidence indicating that successful oil spill prevention can be attributed to government policy (6). Although voluntary regulations are faster to implement that government policy, government policy is stricter (6). While it is difficult to set overarching policies for a country, a combination of corporate social responsibility and government policy, with a top-down approach, could help this issue. The government could set safety goals while corporations could devise their own processes to meet these goals.

What new policies can be created to prevent spills?

To prevent spills, the United States has implemented government policies such as tugboat escorts for tankers and the creation of refuge spots on tanker routes, which are important when there is high tanker traffic and high potential for spills (8). There are no such legal policies in place for Canada (8), which could be implemented to help prevent spills.

How can policies be changed to help improve safety?

Another issue pertaining to offshore oil transport management is the public availability of information. Under the Canadian jurisdiction, environmental monitoring data on oil transport is not accessible to the public, and access to information was denied to Canadian researchers conducting an audit on Canadian oil and gas management (4). By denying the public access to this information, the public cannot make their own environmental assessments (4), and considering that oil use impacts the public, they should have the right to this information.

How can improvements be made to protect Canada’s coasts?

Tankers are still allowed to pass through ecologically sensitive regions on Canadian coasts, which puts these marine ecosystems at risk (15). More marine protected areas need to be created and managed rigorously (15). Canada could create legal policies to ban traffic in pristine ecological zones. In particular, the Voluntary Tanker Exclusion Zone should become a legal exclusion zone. Further, the West Coast inside passage currently allows the passage of small tankers (11), and policy could be implemented to keep out tankers of any size.

How can spill response be improved?

In most oil spills, only around 10% of spills get removed (3). This calls for a significant improvement to spill response. After the Exxon Valdez accident in Alaska in 1989, Transport Canada released a report with 25 proposals for improvements to oil spill response (8). In 2010, a plan to implement these proposals was made, however they have still not been implemented (8). In addition, the recent recommendations for “world-class tanker safety” have only been proposed, not passed (16). The government needs to be much more proactive in passing policies, since meanwhile spills could be happening and tankers are in use every day.

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Which groups can help implement these recommendations, and how?

Lobby groups and environmental groups can pressure the government in making policy decisions by making advocacy campaigns. These groups can lobby for public access to environmental monitoring data so that public environmental assessments can be made. With access to this information, environmental groups can audit the government in order to assess tanker safety. In addition, environmental groups and lobby groups can then make recommendations to the government for oil spill prevention and contingency plans.

How can the government be persuaded to make changes?

If lobby and advocacy groups could gain strong public support, this would help in persuading the government. Support can be gained by raising awareness of how oil tanker policies need to be improved, and what the risks and consequences of oil spills are. Once enough of the public supports the issue, government parties may change their environmental platform to attract voters in election campaigns.

How can the coast be protected?

Funds can be raised by environmental organizations so that researchers can identify regions of coast that are most at risk and assess which areas need to be protected. This way, they can recommend to the government which areas to protect.

What can local citizens do?

Citizens can support lobby groups, write letters to the government, and donate to environmental organizations such as Living Oceans, the Wilderness Committee, Greenpeace and the Dogwood Initiative to help advocate for better tanker safety and access to information.

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1. Burgherr, “In-Depth Analysis of Oil Spills,” 245-256.

2. Dickens, The Double Hull Issue, 25.

3. “Federal Tanker Safety Plan,” Wilderness Committee, Last modified March 18, 2013, Accessed March 18, 2013, LINK.

4. Fraser and Ellis. “The Canada-Newfoundland Atlantic Accord Implementation Act,” 312-316.

5. Hotte and Sumaila. “Potential Economic Impact of a Tanker Spill,” 1-45.

6. Frynas, “Corporate Social Responsibility,” 4.

7. Jernelöv, “The Threats from Oil Spills,” 353-366.

8. Mark Turner, “Review of Offshore Oil-spill,” Department of Natural Resources, Last Modified December 2010, Accessed March 17, 2013, LINK.

9. “National Oil Spill Preparedness and Response Regime,” Transport Canada, Last modified April 16, 2012, Accessed March 17, 2013, LINK

10. “Oil Spill Science and Technology,” 1-41.

11. “Oil Tanker Safety and Oil Spill Prevention,” Transport Canada, Last modified January 4, 2013, Accessed March 17, 2013, LINK.

12. “Oil Tanker Spill Statistics 2012,” The International Tanker Owners Pollution Federation Limited, Last modified 2012, Accessed March 17, 2013, LINK.

13. “Pollution Preparedness and Response,” International Maritime Organization, Accessed March 17, 2013, LINK.

14. Venosa and Zhu, “Biodegradation of Crude Oil,” 163-178.

15. “When Oil and Water Mix,” The Dogwood Initiative, Last modified March 16, 2012, Accessed March 17, 2013, LINK.

16. “World-Class Tanker Safety System: Safe Tankers Through Rigorous Inspection and Prevention,” Last modified March 18, 2013, Accessed March 18, 2013, LINK.

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Burgherr, Peter. “In-Depth Analysis of Accidental Oil Spills from Tankers in the Context of Global Spill Trends from all Sources.” Journal of Hazardous Materials 140, no. 1 (2007): 245-256.

Dickens, D.F. The Double Hull Issue and Oil Spill Risk on the Pacific West Coast. Victoria: Dickens, 1995. LINK.

“Federal Tanker Safety Plan an Insult to British Columbians: Wilderness Committee.” Wilderness Committee. Last modified March 18, 2013. Accessed March 18, 2013. LINK.

Fraser, Gail S. and Joanne Ellis. “The Canada-Newfoundland Atlantic Accord Implementation Act: Transparency of the Environmental Management of the Offshore Oil and Gas Industry.” Marine Policy 33, no. 2 (2009): 312-316.

Hotte, Ngaio and Rashid Sumaila. “Potential Economic Impact of a Tanker Spill on Ocean-Based Industries in British Columbia.” Fisheries Centre Research Report 20, no. 7 (2012): 1-45.

Jedrzej G. Frynas. “Corporate Social Responsibility Or Government Regulation? Evidence on Oil Spill Prevention.” Ecology and Society 17, no. 4 (2012): 4-4.

Jernelöv, Arne. “The Threats from Oil Spills: Now, then, and in the Future.” Ambio 39, no. 5-6 (2010): 353-366.

“National Oil Spill Preparedness and Response Regime.” Transport Canada. Last modified April 16, 2012. Accessed March 17, 2013. LINK

Oil Spill Science and Technology: Prevention, Response, and Cleanup. NL: Gulf Publishing Company, 2010.

“Oil Tanker Safety and Oil Spill Prevention.” Transport Canada. Last modified January 4, 2013. Accessed March 17, 2013. LINK.

“Oil Tanker Spill Statistics 2012.” The International Tanker Owners Pollution Federation Limited. Last modified 2012. Accessed March 17, 2013.LINK.

“Pollution Preparedness and Response.” International Maritime Organization. Accessed March 17, 2013. LINK.

Turner, Mark. “Review of Offshore Oil-spill Prevention and Remediation Requirements and Practices in Newfoundland and Labrador.” Department of Natural Resources. Last Modified December 2010. Accessed March 17, 2013. LINK.

Venosa, Albert D. and Xueqing Zhu. “Biodegradation of Crude Oil Contaminating Marine Shorelines and Freshwater Wetlands.” Spill Science and Technology Bulletin 8, no. 2 (2003): 163-178.

“When Oil and Water Mix.” The Dogwood Initiative. Last modified March 16, 2012. Accessed March 17, 2013. LINK.

“World-Class Tanker Safety System: Safe Tankers Through Rigorous Inspection and Prevention.” Last modified March 18, 2013. Accessed March 18, 2013. LINK.