La Conchita Information
Recent Rainfall Totals
| TIME PERIOD | SEACLIFF FIRE STATION | LA CONCHITA BLUFF |
|---|---|---|
| 14 – Day Total | ||
| 28 – Day Total | ||
| 24 – Hour Total | ||
| Peak Rate | ||
| Last Updated | ||
Community of La Conchita
The steep coastal bluffs adjacent to the community of La Conchita, located along the north coast of Ventura County, are subject to debris flows and ground movement and have experienced multiple significant events, including catastrophic failures in 1995 and 2005. Due to these ongoing and potentially hazardous conditions, the community of La Conchita is designated as Geological Hazard Area and is under a year-round advisory. Under this advisory, the threat to lives in not yet imminent. Due to the potential for rapidly changing conditions to develop into a serious threat, residents are advised to prepare for the issuance of an Evacuation Order should a failure start to occur.
Due to the complex geologic conditions present in the community, local public safety agencies cannot predict when or if a hillside failure may occur. When historical debris-flow thresholds are approached or when active signs of hillside instability are observed, Ventura County Sheriff’s Emergency Services may issue additional advisories or evacuation orders. Residents and visitors should not wait for official evacuation orders before leaving the area if they feel unsafe. Individuals present in the area are responsible for closely monitoring the weather forecast, rainfall rates, and visible hillside conditions, and for taking early action to evacuate during periods of elevated risk.
Past Event Indicators
When looking back at past landslides and hillside failures in La Conchita, public safety officials have identified a common factor present during many of those events: how wet the ground was before the failure occurred. This is known as antecedent moisture, which simply means the amount of water already in the soil from rainfall over the previous days or weeks. While very wet soil or reaching these past moisture levels does not mean a hillside failure will occur, it helps officials understand when the hillside may be more unstable based on past events. Residents are encouraged to stay aware of recent rainfall and changing conditions and to consider taking early action, including leaving the area, if they feel unsafe rather than waiting for official evacuation notices.
During past hillside failures, one or more of the following conditions were observed prior to the failure occurring:
15″ of rainfall in 30 days or less
- The 1995 La Conchita Landslide occurred two months after the area received approximately 15″ of rainfall over a 30 day period.
- Ground cracks, bulging and sloughing at the toe of the slope were also observed several months prior to the 1995 failure.
8″ of rainfall in any two-week period
- The 2005 landslide occurred at the culmination of a 2-week period where approximately 8″ of rain fell.
Rainfall rates in excess of 1-inch per hour
- A small landslide impacted on property in December 2010 following a storm that produced rain at a rate of 1″ per hour.
Types of Geologic Events
The community of La Conchita is subject to several types of hillside-related hazards due to the steep terrain located above the neighborhood. One potential hazard is a catastrophic hillside failure, in which a large, ancient landslide mass above the community could suddenly move downslope and impact homes. A failure of this nature occurred in 1995. Such an event could happen with little or no warning.
Another potential hazard is mudflows, which are fast-moving flows of mud and debris that can travel through the community. Mudflows have the potential to affect all residences as well as access roads, which may limit the ability to enter or leave the area.
In some situations, a catastrophic hillside failure and mudflows could occur at the same time, increasing the overall impact to the community. This type of combined event was observed in 2005, during a period when the ground was already saturated from prior rainfall and the area experienced high-intensity rain exceeding one inch per hour rates.
To reduce additional risk, no excavation or grading should be performed within the community unless it is first reviewed and recommended by a qualified geologist or geotechnical engineer and approved by the County of Ventura Public Works Agency.
Geological Reports & Community Presentations
Recent Geologist Reports
| Public Date | Description | Download Link |
| 1/20/2026 | Post-Rain Geologist Observation Report | |
| 1/5/2026 | Post-Rain Geologist Observation Report |
Comprehensive Hillside Study Reports
| Public Date | Description | Download Link |
| 8/28/2009 | Slope Stabilization Project Report | |
| 10/1/2005 | USGS Landslide Hazards Report |