Long Beach, CA
File #: 23-0240    Version: 1 Name: ER - Elevation Changes Nov 2021-October 2022
Type: Agenda Item Status: Approved
File created: 3/6/2023 In control: City Council
On agenda: 3/21/2023 Final action: 3/21/2023
Title: Recommendation to receive and file the attached report, “Elevation Changes in the City of Long Beach, November 2021 through November 2022.” (Citywide)
Sponsors: Energy Resources
Attachments: 1. 032123-C-10sr&att.pdf
TITLE
Recommendation to receive and file the attached report, “Elevation Changes in the City of Long Beach, November 2021 through November 2022.” (Citywide)

DISCUSSION
The City of Long Beach (City), through the Energy Resources Department (ER), supervises oil production and subsidence control operations in the Wilmington Oil Field. ER conducts surface elevation surveys every six months to monitor surface elevation changes in the oil fields and adjacent city areas. This report focuses on surface elevation changes that have occurred from November 2021 through November 2022. The ER survey includes the following areas: Civic Center, Central City, Alamitos Bay, Naples, Harbor District, and the offshore area encompassing the four oil islands.

The results of the last two six-month surveys indicate that surface elevations were stable in the Civic Center, Central City, Alamitos Bay, Naples, and the offshore islands. During the first six-month period rises were observed in the Harbor District and Shoreline Village area of up to 0.067 foot (0.80 inch) and 0.055 foot (0.66 inch), respectively. These surface elevation changes are considered minor and are likely due to changes in injection volumes within the Wilmington Oil Field. Surface elevation rises of up to 0.069 foot (0.83 inch) were observed in the Port of Los Angeles and near Recreation Park. These changes are considered minor and are possibly due to normal tectonic movement along the active Palos Verdes and Newport-Inglewood fault zones.

The rising trend observed in the Harbor District during the first six-month period reversed in the second six-month period, resulting in a surface elevation loss of as much as 0.074 foot (0.88 inch). This surface elevation loss was expected due to controlled changes in fluid injection volumes. Additional surface elevation changes of up 0.061 foot (0.73 inch) were observed outside of the Wilmington Oil Field operated areas, specifically near Recreation Park, the south...

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