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LEFT: Smoke is visible from controlled burns of the oil released during the Deepwater Horizon oil spill in 2010. This was the largest oil spill in U.S. waters (Credit: NOAA). RIGHT: A rainbow sheen on the water is one indication that there may be oil floating on the surface (Credit: NOAA).
Oil is a fossil fuel. Fossil fuels (oil, natural gas, and coal) are materials formed over millions of years from the remains of ancient plants and animals. We use oil to heat our homes, generate electricity, and power large sectors of our economy. But when oil accidentally spills into the ocean, it can cause big problems. Oil spills harm sea creatures, make seafood unsafe to eat, and can even ruin your day at the beach.
Oil is found below ground or below the ocean floor in “pores” or holes in the rock called reservoirs. After drilling down and pumping out the crude oil, it is transported by pipes, ships, trucks, or trains to processing plants called refineries. Here the crude oil is broken down so it can be made into different petroleum products, including gasoline and other fuels as well as products like asphalt, plastics, soaps, and paints.
Sometimes accidents happen when removing the crude oil from underground or in transporting it by ship or pipeline to a refinery. These accidents can spill oil into the environment.
Large oil spills are major, dangerous disasters. These tend to happen when pipelines break, big oil tanker ships sink, or drilling operations go wrong. Ecosystems and economies can feel the consequences for decades following a large oil spill.
Oil spills can happen anywhere oil is drilled, transported, or used, and they are more common than you might think. Thousands of oil spills occur in U.S. waters each year. Most of these spills are small, for example, oil may spill while refueling a ship. But these spills can still cause damage, especially if they happen in sensitive environments, like beaches, mangroves, and wetlands.
Accidents involving tankers, barges, pipelines, refineries, drilling rigs, and storage facilities are the most common cause of oil spills, but recreational boats can also release oil out on the water or in marinas.
Spills can be caused by:
Oil can be spilled anywhere oil is extracted, transported, or used. (Credit: NOAA.) Learn more about where oil spills come from.
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