COMMUNITY OF LA CONCHITA

The steep coastal bluffs adjacent to the community of La Conchita, along the north coast of Ventura County, are prone to debris flows and land movement. This area has experienced multiple major events over the years, including catastrophic events in both 1995 and 2005.

Due to the complex nature of the geologic hazards in this area, local public safety personnel have no way to predict if and when a failure of the hillside may occur. As historical thresholds for debris flows are reached or active failures of the hillside are detected, Ventura Sheriff’s Emergency Services may issue evacuation notices to area residents. However, individuals should not wait for local authorities to issue evacuation warnings or orders before leaving the area should they feel unsafe. It is incumbent upon residents and visitors to exercise due diligence in monitoring weather forecasts, rainfall rates and current hillside conditions, and taking early action to evacuate during periods of increased risk.

Additionally, any decision to lift evacuation orders for the community of La Conchita should not be construed that the area has been deemed safe and/or free of geological hazards. As always, the hillside remains susceptible to debris flows and landslides.

The Community of La Conchita has been deemed a geologic hazard area by the County of Ventura. County officials advise against entry into the area under any circumstance. 

Based on the present information known about ancient landslides and the 1995 and 2005 landslides, the following geologic hazards are present:

1. Catastrophic Failure: The large ancient landslide mass located above the community could potentially fall, impacting residences within the community at any time, without warning.
2. Mudflows: Mudflows could potentially impact all residences and access roads within the community.
3. Catastrophic failure and mudslides: Should both event occur simultaneously, the community could be impacted.
4. No excavation (removal of earth material) or grading should be performed in the community without recommendations from a geologist and/or geotechnical engineer and review by the County of Ventura Public Works Agency.

La Conchita Historical Event Triggers

The following historical triggers help serve as indicators for a potential geological event at La Conchita:

• 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.
• 1″ of rainfall per hour or greater carriers the potential to trigger flooding, landslides or debris flows at any location.
  • A small landslide impacted on property in December 2010 following a storm that produced rain at a rate of 1″ per hour.

Weather Forecast Resources & Live Radar Feeds

• National Weather Service – Oxnard Office
• Ventura County Public Works Agency – Water Protection

Recent Rainfall (in inches)

Presentations