Lakeview Gusher Number One was an eruption of hydrocarbons from a pressurized oil well in the Midway-Sunset Oil Field in Kern County, California, in 1910. It created the largest accidental oil spill in history, lasting 18 months and releasing 9 million barrels (1.4×106 m3) of crude oil.
Midway-Sunset was one of the largest oil reserves in America. When drilling commenced, the Lakeview Oil Company expected natural gas and a small amount of oil. Instead, there was a large blowout which overloaded storage tanks.
The 9-million-barrels (1.4×106 m3) geyser released more than 1.2 million US tons of crude, far more than any other single leak on land or water. Its site is located about a half-mile (800 m) east of the Taft–Maricopa Highway, California Route 33, marked by a Caltrans guide sign and a bronze plaque designated as California Historical Landmark number 485.
The Lakeview Oil Company started drilling at their Number One well on 1 January 1909. Initially only natural gas was found. As work continued the company partnered with Union Oil, which wanted to build storage tanks there.
Early twentieth-century drilling technology lacked such modern safety features as blowout preventers. When drilling reached 2,440 ft (740 m) on 14 March 1910] pressurized oil blew through well casing above the bit. An estimated 9 million barrels (1.4×106 m3) escaped before the gusher was brought under control in September 1911.
Initial daily flow was 18,800 barrels (2,990 m3), creating a river of crude that crews rushed to contain with improvised sand bag dams and dikes. Peak flow reached some 90,000 barrels (14,000 m3), diverted via pipeline to storage tanks 2.5 miles (4.0 km) away, where an 8-inch (200 mm) line led to Port Avila on the coast.
In spite of these efforts, less than half of the 9.4 million barrels released during the gusher’s 544 days was saved, the rest evaporating off or seeping into the ground.