Soil Conditions in Glendale
Los Angeles County's geology is as varied as its neighborhoods. Here's what we typically find.
Verdugo Mountains Alluvial Fan
The flatlands of Glendale are built on alluvial fan deposits shed from the Verdugo Mountains and San Gabriel Mountains. These deposits consist of interbedded gravels, sands, and silts that generally become coarser and more bouldery closer to the mountain fronts.
Collapsible and Expansive Soils
Upper alluvial fan deposits in northern Glendale can be collapsible — soils that settle suddenly when saturated under load. Expansive clays are also found in the older alluvium and bedrock-derived soils in hillside areas, requiring special foundation design to mitigate shrink-swell movement.
Verdugo Fault and Seismic Hazards
The Verdugo fault traverses the base of the Verdugo Mountains along the north edge of Glendale. Hillside areas are mapped within seismic hazard zones for earthquake-induced landslide, and portions of the flatland are designated liquefaction hazard zones. Both conditions trigger additional geotechnical study requirements.
Hillside Bedrock and Debris Flow Risk
Glendale's hillside neighborhoods are underlain by crystalline basement rock and Tertiary sedimentary formations. Steep terrain combined with post-wildfire conditions creates debris flow risk in canyon areas. Geologic investigation including slope stability analysis is standard for hillside development.
What We Do in Glendale
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 Glendale
Hillside Single-Family Home
New homes in the Verdugo Mountains foothills require comprehensive geologic and geotechnical investigation, engineered foundations (often caissons or piers), and retaining wall design.
ADU / Accessory Dwelling Unit
Glendale's flat neighborhoods are seeing strong ADU growth. Most ADUs require at minimum a soils report to support the building permit application.
Multi-Family Residential
Infill apartment and condominium projects along Brand Boulevard and downtown Glendale corridors require geotechnical investigation for podium and subterranean parking structures.
Retaining Walls
Hillside lots frequently need engineered retaining walls to create level building pads. Glendale requires geotechnical design parameters and a geology evaluation for all retaining walls exceeding four feet in height.
Working With City of Glendale Community Development Department
Glendale requires geotechnical and geology reports for new construction, hillside development, and projects involving significant grading. The city employs staff geologists who review all geotechnical submittals. Hillside development permits are subject to additional environmental and geologic review.
What Makes This Jurisdiction Distinct
Hillside development permit required for construction in the hillside overlay zone
Engineering geology report required in addition to soils report for hillside projects
Debris flow hazard evaluation required for properties in canyon and post-fire areas
Grading quantities restricted in hillside areas with enhanced environmental review
Seismic hazard zone investigations (liquefaction, landslide) required per state mapping
Glendale requires geotechnical reports to be submitted with the grading or building permit application at the Community Development counter. Hillside projects should anticipate geology review comments and plan for a pre-application meeting.
Common Questions — Glendale
Building in Glendale?
Tell us about your project and we'll send you a fixed-fee proposal — typically within one business day.