The Rio Vista Gas Field is a natural gas field located in Solano County, California, United States. It lies within the Sacramento-San Joaquin River Delta region, near the town of Rio Vista, approximately 50 miles northeast of San Francisco. Discovered in the 1930s, it is one of the largest onshore natural gas fields in California in terms of original gas in place. Production primarily comes from Pliocene-age sandstone reservoirs at depths ranging from 5,000 to 10,000 feet.
The field has been operated over the years by various energy companies, with historical operators including Shell Oil Company and later smaller independent producers. Production from the field has declined over time due to prolonged extraction, though it remains active as of recent reports. The geologic structure is characterized by a series of anticlinal folds, which serve as traps for natural gas accumulation.
The Rio Vista Gas Field has also been the subject of environmental monitoring due to its proximity to ecologically sensitive wetland areas and waterways in the Delta region. Regulatory oversight includes compliance with air quality and greenhouse gas emission standards set by the California Air Resources Board and the Solano County Air Quality Management District.
Current production data and operator details may vary; specific information on reserve estimates and annual output is maintained by the California Department of Conservation, Division of Oil, Gas, and Geothermal Resources (DOGGR).
This field is distinct from offshore or other onshore fields in California and is recognized in state energy records and geological surveys.