Despite repeated claims that well stimulation in California uses “millions of gallons of water per well,” the amount of water used here is quite small when compared to other uses for water. How small?
According to 568 well reports filed with the FracFocus public website, the average amount of water used for well stimulation in California in 2012 was 116,535 gallons per well. That’s less than half the amount of water needed to irrigate a golf course for a single day.
The total amount of water used in the 568 well stimulation operations reported in 2012 was slightly less than 66 million gallons – or 202 acre feet. On average, agriculture utilizes 34 million acre feet of water annually4 and cities/towns consume slightly less than 10 million acre feet annually (5).
There is a large variation in the amount of water used for well stimulation, according to the FracFocus reports. The smallest amount of water used was 6,645 gallons. The largest amount was 1.5 million gallons. Only two well stimulation operations reported on FracFocus in California in 2012 used more than 1 million gallons.
According to FracFocus data, 97 percent of the well stimulation that was reported for California took place in Kern County.
The Facts about Water
The average amount of water used to hydraulically fracture an oil well in California in 2012
The average amount of water used by a four-person family living for one year. (1)
The amount of water needed to irrigate a golf course in a single day
202 acre feet:
The total amount of water used in California for well stimulation in California in 2012
400,000 acre feet:
The total amount of water used for municipal purposes in Kern County in 2011 (2)
2.7 million acre feet:
The total amount of water used for growing food and fiber in Kern County in 2011 (2)
121.8 billion gallons:
The amount of water produced along with oil and natural gas in California in 2011 (3)
34 million acre feet:
The total amount of water used for agriculture
Oil and natural gas producers in California are experts at managing large amounts of water – much larger than the amounts needed for well stimulation. Vast amounts of water are produced along with oil from deep underground reservoirs or formations. According to the California Department of Conservation’s Geologic Energy Management Division (CalGem), 196 million barrels of oil were produced in Kern County in 2011 and 2.9 billion barrels or 121.8 billion gallons of water came with them.
After producing oil in Kern County and elsewhere in California for more than 100 years, oil companies have a tremendous amount of skill and expertise at safely handling, using and disposing of this so-called “produced water.”
Both well stimulation fluids and produced water are handled in accordance with California’s water quality regulations. Disposal of both are subject to permit requirements. For example, produced water and well stimulation fluids must be stored either in enclosed tanks or lined ponds to prevent leakage to groundwater. They must be tested regularly to determine if they meet state and federal hazardous material criteria and disposed of accordingly.
Approximately 60 percent of the produced water is disposed of in the estimated 25,000 injection wells that are permitted and regulated by CalGem. The remaining produced water is either recycled for enhanced oil recovery purposes or treated and sold for agricultural purposes.
- Class I injection wells are used to dispose of hazardous and non-hazardous wastes including well stimulation fluids below the lowermost underground source of drinking water (USDW). Injection occurs into deep, isolated rock formations that are separated from the lowermost USDW by layers of impermeable clay and rock. The average depth of an injection well in California is about 5,000 feet, or one mile.
- Class II wells are used to inject fluids associated with oil and natural gas production operations. Most of the injected fluid is brine that is produced when oil and gas are extracted from the earth.
Much of the conventional oil production in California uses enhanced oil recovery technologies like steam injection and water flooding. These technologies have been in use for many decades and have dramatically extended the productive life of the state’s oil fields.
Some of these technologies require fresh water with different characteristics than produced water. Oil companies obtain the water needed for oil and gas production from the same sources all other water users utilize. They either use surface or ground water they own as part of their property rights; they purchase water from water agencies with water
for sale; or they purchase water from individuals or corporate entities with water to sell.