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Historical - Oil Operations

Wilmington Oil Field 

The Wilmington Oil Field is the third largest field in the contiguous United States with an ultimate recovery estimated at three billion barrels of oil. The field is located on the 13 mile long and 3 mile wide Wilmington Anticline that extends from onshore San Pedro to offshore Seal Beach and is divided vertically by faults creating separate producing entities called Fault Blocks. Oil is produced from five major sand intervals ranging in depths from 2,000 feet to 11,000 feet where over two and one-half billion barrels of oil have been recovered. Oil and Gas are recovered through primary production, secondary water flooding, and steam flooding. A total of 6,150 wells have been drilled to date. 

Oil Operating Areas


Oil Operations

In the Wilmington Oil Field, which encompasses both tidelands and uplands properties, DOP oversees the work of two private contractors and their 300 employees. Tidelands Oil Production Company is the Field Contractor for west Wilmington. Since 1932, more than 3,400 land based wells have been drilled. In the 1950's and 1960's, water flooding was initiated to increase recovery and control subsidence.


California Resources Corporation (CRC) is the field Contractor for the Long Beach Unit (LBU), the eastern offshore portion of the Wilmington Field. THUMS Long Beach Company (named for the original Field Contractors: Texaco, Humble, Union, Mobil, and Shell) is the agent for CRC. In 1964 four man-made islands, named after the astronauts that lost their lives during the early years of the U.S. space exploration (Grissom, White, Chaffee, and Freeman), were built. Pier J was expanded into the Long Beach Harbor to develop the LBU. Approximately 1,450 wells have been drilled. The Long beach Unit began water flooding at start-up to help prevent subsidence. Today, Wilmington Field oil production is approximately 46,000 barrels per day from 1,550 active wells. 

Island Schematic 


Island Grissom


In the Uplands, the City is both a royalty participant and a working interest owner in its properties adjacent to Signal Hill and other properties throughout the City. The Signal Hill West Unit (SHWU) and Signal Hill East Unit (SHEU) is part of the Long Beach oil field located in both Long Beach and Signal Hill. The surface expressed anticline structure is visible for miles and is a local landmark next to the Long Beach airport. Signal Hill Petroleum Inc. is currently the operator of record. Recreation Park is located on the north side of 7th Street. A total of 7 wells are now operated by Breitburn Energy Company LLC, a Los Angeles based independent oil company. The City Wasem Community Lease is located near Marine Stadium, which is an extension of the Seal Beach oil field. The Marine area oil pool was discovered and developed in 1979 by Elliot & Ten Eyck (ET). The lease currently has 16 active wells.