Oil spills

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Oil is an ancient fossil fuel that we use to heat our homesgenerate electricityand power large sectors of our economy. But when oil accidentally spills into the oceanit can cause big problems. Oil spills can harm sea creaturesruin a day at the beachand make seafood unsafe to eat. It takes sound science to clean up the oilmeasure the impacts of pollutionand help the ocean recover.

A sea turtle covered in oil.

Juvenile Kemp's ridley sea turtle oiled in the Deepwater Horizon spill in 2010. (Image credit: Blair Witherington/Florida Fish and Wildlife Conservation Commission)

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What is oil?

Crude oilthe liquid remains of ancient plants and animalsis a fossil fuel that is used to make a wide range of fuels and products. Oil is found below ground or below the ocean floor in reservoirswhere oil droplets reside in “pores” or holes in the rock. After drilling down and pumping out the crude oiloil companies transport it by pipesshipstrucksor trains to processing plants called refineries. There it is refined so it can be made into different petroleum productsincluding gasoline and other fuels as well as products like asphaltplasticssoapsand paints.

How do oil spills happen?

Oil spills are more common than you might thinkand they happen in many different ways. Thousands of oil spills occur in U.S. waters each year. Most of these spills are smallfor example when oil spills while refueling a ship. But these spills can still cause damageespecially if they happen in sensitive environmentslike beachesmangrovesand wetlands.

Large oil spills are majordangerous disasters. These tend to happen when pipelines breakbig oil tanker ships sinkor drilling operations go wrong. Consequences to ecosystems and economies can be felt for decades following a large oil spill.

Where do oil spills happen?

Oil spills can happen anywhere oil is drilledtransportedor used. When oil spills happen in the oceanin the Great Lakeson the shoreor in rivers that flow into these coastal watersNOAA experts may get involved. The Office of Response and Restoration’s mission is to develop scientific solutions to keep the coasts clean from threats of oilchemicalsand marine debris.

A map showing the Largest Oil Spills Affecting U.S. Waters from 1969 - 2024. 49 oil spills are shownaffecting coastal waters in Alaskadown the West Coastoff Hawaiithe Gulf of Mexico and Caribbeanthe East Coastand the Great Lakes. More information can be found at https://response.restoration.noaa.gov/oil-and-chemical-spills/oil-spills/largest-oil-spills-affecting-us-waters-1969.html.
 Largest oil spills affecting U.S. waters since 1969-2024. (NOAA/Office of Response and Restoration)

 

How do oil spills harm or kill ocean life? 

Where the oil is spilledwhat kinds of plantsanimalsand habitats are found thereand the amount and type of oilamong other thingscan influence how much harm an oil spill causes. Generallyoil spills harm ocean life in two ways:

Fouling or oiling: Fouling or oiling occurs when oil physically harms a plant or animal. Oil can coat a bird’s wings and leave it unable to fly or strip away the insulating properties of a sea otter’s furputting it at risk of hypothermia. The degree of oiling often impacts the animal’s chances of survival.

Oil toxicity: Oil consists of many different toxic compounds. These toxic compounds can cause severe health problems like heart damagestunted growthimmune system effectsand even death. Our understanding of oil toxicity has expanded by studying the effects of the 2010 Deepwater Horizon oil spill.

Wildlife recoverycleaningand rehabilitation is often an important part of oil spill response. However wildlife is difficult to find and catchoil spills can happen over wide areasand some animals (like whales) are too big to recover. Unfortunatelyit’s unrealistic to rescue all wildlife impacted during oil spills.

Who cleans up an oil spill — and how?

The U.S. Coast Guard is primarily responsible for cleaning up oil spillswhile NOAA experts provide scientific support to make smart decisions that protect people and the environment. There are different equipment and tactics that trained experts can use to contain or remove oil from the environment when a spill occurs. Booms are floating physical barriers to oilwhich help keep it contained and away from sensitive areaslike beachesmangrovesand wetlands. Skimmers are used off of boats and can “skim” oil from the sea surface. In situ burningor setting fire to an oil slickcan burn the oil away at seaand chemical dispersants can break up oil slicks from the surface.

Howevercleanup activities can never remove 100% of the oil spilledand scientists have to be careful that their actions don’t cause additional harm. After the Exxon Valdez oil spill in 1989scientists learned that high-pressurehot-water hoses used to clean up beaches caused more damage than the oil alone. Sensitive habitats need extra consideration during oil spill cleanup.

Who pays for oil spill cleanup and restoration? 

The Oil Pollution Act of 1990 established (among other things) that those responsible for oil spills can be held responsible to pay for cleanup and restoration. This process of assessing the impacts of a spill and reaching a settlement to fund restoration projects is called Natural Resource Damage Assessment (NRDA). Federalstateand tribal agencies work together with the party responsible for the oil spill throughout NRDA and select restoration projects with help from the public.

Working with partners from statetribaland federal agencies and industryNOAA helps to recover funds from the parties responsible for the oil spillusually through legal settlements. Over the last 30 yearsNOAA has helped recover over $9 billion from those responsible for the oil spill to restore the ocean and Great Lakes.

How does NOAA help after an oil spill?

When a person gets sicka doctor evaluates their symptomsdiagnoses a problemand then prescribes a treatment to help them get better. That’s also what NOAA experts do after an oil spill: they evaluate what happenedassess the impactsand then design restoration projects to help the ocean recover. Restoration isn’t the same as cleanup. It requires projects like building marshland or protecting bird nesting habitat to actively bolster the environment.

Restoration projects are important because they speed up the amount of time it takes for different species and habitats to recover. In addition to restoring habitatsthe group responsible for the spill may also be held accountable for restoring access to natural spaces by constructing parksboat rampsand fishing piers.

What are the largest marine oil spills in American history?

There are three oil spills that stand out in American historyeach of which was the largest oil spill into American waterways at the time. In 1969a blowout on an offshore platform off the coast of Santa BarbaraCaliforniaspilled over four million gallons of oil. In 1989the Exxon Valdez oil tanker ran aground in the Prince William Sound in Alaskaspilling over 11 million gallons of oil.

The largest marine oil spill in all of U.S. history was the Deepwater Horizon spill. On April 202010an explosion occurred on the Deepwater Horizon drilling platform in the Gulf of Americakilling 11 people. Before it was capped three months laterapproximately 134 million gallons of oil had spilled into the ocean. That is equivalent to the volume of over 200 Olympic-sized swimming pools. An $8.8 billion settlement for restoration was reached in 2016and restoration is still continuing today.

EDUCATION CONNECTION

Though we tend to be the most familiar with the massive incidents like Deepwater Horizondid you know that thousands of smaller oil spills occur each yearsome spilling less than a barrel of oil? Oil spillsin addition to nonpoint source pollutionthreaten our ocean ecosystem. Learning about pollutionas well as our role in our ecosystemcan help protect ocean habitats by improving stewardship behaviors.

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