Graphic by Bryan Christie
Oil rigs are a curious feature of this city—they seem more Texas than SoCal. But local drilling dates to 1892, when Edward Doheny (who inspired There Will Be Blood) noticed some black goo downtown and snapped up 1,000 acres. By 1925, California was supplying nearly a quarter of the world’s oil. These days roughly 40 pumping fields are in operation in our part of the state, extracting 28 million barrels of crude per year. Here, a guide to L.A.’s slick side.
1. The Well
Oil wells in urban L.A. run horizontally underground, curving outward like tentacles from the well head sites. The wells are typically one to two miles long, making it possible for companies to tap the massive amount of crude under the city from just a few dozen locations. As the “donkey” bobs, the bridle and polished rod keep fluid from seeping out.
2. The Water
To increase the amount of oil accumulated from drilling, pressurized saltwater is squirted into the reservoir from a separate water well. The water sweeps the remaining oil to the producing wells. It’s then recycled back into the injection wells.
3. The Processing
After crude oil is pumped to the surface, it travels through an underground pipeline to a central facility that separates the oil from the saltwater. The vast majority of what oil companies remove from the ground is saltwater; a small percentage is crude oil.
4. The Pump
Pump jacks move up and down, forcing an oil-and-water mixture out of the ground. Depending on the size of the pump, between a gallon and ten gallons of liquid are pushed up with each stroke. Most pump jacks use a kind of engine called a “prime mover.” Rigs tend to rely on electric motors to drive the gear box, which turns a lever that runs the pump.
5. The Result
Regional oil makes up only 4 percent of the 653 million barrels of oil consumed in California every year. Though it could be used for gas, most goes into making asphalt roads and shingles because the consistency is thick and goopy. It’s cheaper to guzzle from the Alaska pipeline, which supplies much of our state with fuel.