Volume and extent of the Deepwater Horizon oil spill Volume and extent of the Deepwater Horizon oil spill The "Deepwater Horizon" oil spill was discovered on the afternoon of 22 April 2010 when a large oil slick began to spread at the former rig site. According to the Flow Rate Technical Group, the leak amounted to about of oil, exceeding the 1989 "Exxon Valdez" oil spill as the largest ever to originate in U.S.-controlled waters and the 1979 Ixtoc I oil spill as the largest spill in the Gulf of Mexico. BP has challenged this calculation saying that it is overestimated as it includes over of oil which was
1969 Santa Barbara oil spill which devastated coastal areas in both England and France, and the burning of the Cuyahoga River in downtown Cleveland, Ohio. At the time, the Santa Barbara spill was the largest oil spill ever in U.S. waters, and its occurrence during a fierce battle between local residents and the very oil company responsible for the spill only made the controversy more intense, the battle more public, and the anti-oil cause seem more valid to a wider segment of the populace. In the several years after the spill, more environmental legislation was passed than in any other similar period in U.S. history.