What Are Subsidenceand Sinkholes?
By JC Pacific Corp Published 2026-09-01 Last professionally reviewed: September 2026
Subsidenceis the sinking or lowering of the ground surface. A sinkholeis a localized depression or collapse associated with underground voids or loss of support. In California, ground movement can also result from groundwater withdrawal, mining, tunnels, leaking utilities, fill, or other conditions.
What can cause subsidence?
Possible causes include:
- Groundwater extraction
- Underground mining
- Oil or gas extraction
- Collapsible soil
- Decomposition of buried material
- Poorly compacted fill
- Leaking water or sewer lines
- Underground cavities
- Construction activity
What warning signs should buyers investigate?
Potential signs include:
- New ground depressions
- Widening cracks
- Repeated pavement failure
- Tilting structures
- Utility breaks
- Doors suddenly binding
- Separating foundations
- Unexplained drainage changes
Stay away from sudden ground collapseand notify emergency or utility authorities when safety is threatened.
Is subsidence covered by insurance?
Standard homeownersand flood policies commonly exclude many forms of earth movement, subsidence,and sinkhole damage. Specialized coverage may be limited.
Frequently Asked Questions
Are California sinkholes the same as Florida sinkholes?
Not necessarily. Geologyand causes differ by location.
Can a sewer leak create ground settlement?
Potentially. A qualified professional should determine the cause.
Should buyers research old mines or wells?
Yes, when local history or records indicate possible underground activity.
Educational information
This content is for general educational purposesand is not insurance, geological, geotechnical, engineering, construction, legal, lending, environmental, financial, or emergency-preparedness advice. Flood mapsand other hazard maps serve specific regulatoryand informational purposesand do not predict whether a particular property will flood, slide, settle, erode, or suffer damage. Insurance coverage, exclusions, premiums, deductibles, limits, waiting periods,and eligibility vary. Consult appropriately licensed professionals regarding a specific property.
Investigate ground movement with the appropriate geological, geotechnical, structural, utility,and legal professionals.
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JC Pacific Corp is an Irvine-based Southern California brokerage helping buyers navigate offers, escrow, and financing. Tell us what you are looking for and we will point you to current options across the region.
A note on legal advice: These guides provide general, educational information about California real estate practice. They are not legal advice and do not create an attorney-client relationship. Mortgage information is general education, not individualized lending, tax or legal guidance. For advice about your specific offer, contract, closing or financing, consult a qualified California real estate attorney and a qualified mortgage professional.
A note on these flood-and-natural-hazard guides: These articles provide general, educational information about California flood hazard, flood insurance, landslides, earth movement, soil conditions,and coastal risks for buyers. They are not an insurance policy, a quote, a binder, a coverage determination, a flood determination, an elevation certificate, an inspection, a survey, a geological or geotechnical report, an engineering evaluation, or a guarantee that any property is safe, insurable, or free from flooding, sliding, settling, erosion, or other damage. Flood mapsand other hazard maps describe identified conditions or regulatory zones but do not predict whether a particular property will suffer damage. Professional roles are separate:a real estate professional is not a geologist, engineer, surveyor, insurer, floodplain administrator, or inspector,and Property DNA is only one supporting research service, never a substitute for official flood maps, Natural Hazard Disclosures, insurance quotes, elevation certificates, inspections, surveys, geological or geotechnical investigations, engineering evaluations, public records, or professional advice. Time-sensitive products, eligibility rules, deductibles, limits, waiting periods,maps,and regulations must be reviewed against current official sources at publication time. For a specific property, consult current FEMA, California,and local maps,and resources,and direct underwritingand coverage questions to a California-licensed insurance professional,and geological, geotechnical, engineering,and other technical questions to the appropriately licensed professional.