Most people think of technology companies or farmland when they think of California. But California has been an oil-producing state since the 1860s. It still produces roughly 300,000 barrels of oil per day, making it one of the top five crude-oil-producing states in the country. Most of that oil comes from the San Joaquin Valley in the center of the state.
Where Does California Produce Oil?
The San Joaquin Valley is home to some of the largest conventional oil fields in the U.S. The Kern River Field near Bakersfield has been producing since 1899 and is one of the most-produced fields in U.S. history. Other major fields include Midway-Sunset, South Belridge, and Lost Hills. These are mostly heavy oil fields — the oil is thick and viscous, so it requires steam injection to flow to the surface. The Los Angeles Basin also has a long history of oil production, with active fields in Long Beach and Wilmington sitting underneath dense suburban neighborhoods.
What Is CalGEM?
In 2021, California renamed its oil and gas regulator from the Division of Oil, Gas and Geothermal Resources (DOGGR) to CalGEM — the California Geologic Energy Management Division. The name change signaled a shift in priorities. CalGEM now emphasizes well safety, groundwater protection, and the transition away from fossil fuels, in addition to regulating active production.
What Does CalGEM Do?
- Issues permits. CalGEM approves new well drilling permits and workover permits for existing wells.
- Enforces setbacks. California has some of the strictest setback rules in the country, requiring new wells to be at least 3,200 feet from homes, schools, and healthcare facilities.
- Monitors well integrity. With thousands of older wells across the state, CalGEM conducts regular inspections and requires pressure testing to catch any leaks before they become environmental problems.
- Publishes public data. Well records, production data, and inspection reports are available on CalGEM's website at conservation.ca.gov/calgem.
The Future of California Oil
California's oil production has been declining for decades. The state has set a goal of phasing out new oil and gas permits over time. Despite this, existing fields continue to produce, and the state remains a significant oil consumer. Understanding California's geology and regulatory environment is important for anyone operating in the western United States.