Soil Conditions in Long Beach
Los Angeles County's geology is as varied as its neighborhoods. Here's what we typically find.
Marine Terrace and Lakewood Formation
Long Beach is underlain by Pleistocene marine terrace deposits and the Lakewood Formation — older alluvial and shallow marine sediments. Near the surface these soils are typically dense to very dense sands and stiff clays, though pockets of loose or soft material occur near former marshlands and tidal channels.
Oil Field Subsidence
The Wilmington Oil Field beneath Long Beach and the harbor area caused significant ground subsidence in the mid-20th century — over 29 feet in some areas before water injection programs arrested the settlement. Residual differential settlement and variable fill placed during remediation can affect foundation performance.
Shallow Groundwater and Liquefaction
Groundwater in much of Long Beach is encountered at shallow depths, often within 10 to 20 feet of the surface near the coast and harbor. Combined with loose sandy soils, this creates liquefaction susceptibility in mapped zones along the coast, the Los Angeles River corridor, and near Signal Hill.
Newport-Inglewood Fault Zone
The Newport-Inglewood fault zone passes directly through Long Beach and Signal Hill. Properties near the fault trace are subject to Alquist-Priolo setback requirements, and many sites within the fault zone require a fault rupture hazard investigation in addition to the standard geotechnical report.
What We Do in Long Beach
Soils Reports
Geotechnical investigation and foundation recommendations for building permits.
Learn more →Grading Plans
Precise and rough grading design with drainage and earthwork calculations.
Learn more →Compaction Testing
Field density testing and fill certification for construction.
Learn more →Stormwater / LID / WQMP
LID/WQMP compliance and BMP design.
Learn more →Hydrology Reports
Drainage analysis and flood risk assessment.
Learn more →Subsurface Exploration
Drilling, CPT, and test pit programs.
Learn more →Erosion Control Plans
SWPPP and erosion control for grading permits.
Learn more →Street Improvements
Frontage, curb, gutter, and sidewalk design.
Learn more →Utility Plans
Water, sewer, and storm drain design and coordination.
Learn more →Project Coordination
One point of contact managing structural, MEP, surveying, and specialty consultants.
Learn more →We also coordinate with your structural engineer, architect, MEP consultants, and other project team members to ensure our deliverables integrate with the overall design — one point of contact for your geotechnical and civil engineering scope.
What People Build in Long Beach
ADU / Accessory Dwelling Unit
ADU construction is booming in Long Beach's established neighborhoods. A soils report is typically required, particularly on properties with shallow groundwater or in liquefaction zones.
Coastal Zone Residential
New homes and major remodels along the coast require geotechnical investigation, coastal engineering review, and compliance with LCP drainage and stormwater requirements.
Multi-Family Infill
Transit-oriented development along the Blue Line corridor and downtown Long Beach drives demand for multi-family projects requiring geotechnical investigation and shoring design for subterranean parking.
Port-Adjacent Industrial
Warehouse and logistics facilities near the Port of Long Beach often encounter variable fill conditions from historical subsidence remediation and require specialized foundation analysis.
Working With City of Long Beach Development Services
Long Beach Development Services requires geotechnical reports for new construction, significant grading, and projects within mapped seismic hazard zones. Reports must be reviewed and approved before grading or building permit issuance. Coastal zone properties require additional compliance with the Local Coastal Program.
What Makes This Jurisdiction Distinct
Geotechnical report required for new construction and grading permits
Liquefaction analysis required for properties within CGS-mapped seismic hazard zones
Coastal Development Permit required for projects within the Local Coastal Program area
Fault rupture hazard investigation required for properties within Alquist-Priolo zones along the Newport-Inglewood fault
Oil field area projects may require evaluation of historical subsidence and variable fill conditions
Submit geotechnical reports with the building or grading permit application through the Long Beach Development Services online portal. Reports must be signed and stamped by a California-licensed Geotechnical Engineer.
Common Questions — Long Beach
Building in Long Beach?
Tell us about your project and we'll send you a fixed-fee proposal — typically within one business day.