Lava Flow Hazard Zones
The below map shows lava-flow hazard zones for the five volcanoes on the Island of Hawaiʻi:
- Kīlauea (active, last eruption: 2018)
- Mauna Loa (active, last eruption: 1984)
- Hualalai (active, last eruption: 1801)
- Mauna Kea (dormant)
- Kohala (extinct)
Volcano boundaries are shown as heavy, dark bands, reflecting the overlapping of lava flows from adjacent volcanoes along their common boundary. Hazard-zone boundaries are drawn as double lines because of the geologic uncertainty in their placement.
Lava-flow hazard zones - Based on location of eruptive vents, past lava coverage, and topography
- Zone 1: Includes summits and rift zones of Kīlauea and Mauna Loa, where vents have been repeatedly active in historical time
- Zone 2: Areas adjacent to and downslope of zone 1. Fifteen to twenty-five percent of zone 2 has been covered by lava since 1800, and twenty-five to seventy-five percent has been covered within the past 750 years. Relative hazard within zone 2 decreases gradually as one moves away from zone 1
- Zone 3: Areas less hazardous than zone 2 because of greater distance from recently active vents and (or) because of topography. One to five percent of zone 3 has been covered since 1800, and fifteen to seventy-five percent has been covered within the past 750 years
- Zone 4: Includes all of Hualālai, where the frequency of eruptions is lower than that for Kīlauea or Mauna Loa. Lava coverage is proportionally smaller, about five percent since 1800, and less than fifteen percent within the past 750 years
- Zone 5: Area on Kīlauea currently protected by topography
- Zone 6: Two areas on Mauna Loa, both protected by topography
- Zone 7: Younger part of domant volcano Mauna Kea. Twenty percent of this area was covered by lava in the past 10,000 years
- Zone 8: Remaining part of Mauna Kea. Only a few percent of this area has been covered by lava in the past 10,000 years
- Zone 9: Kohala Volcano, which last erupted over 60,000 years ago
For detailed explanation and source information, visit United States Geological Survey
Kīlauea Eruption Risk Assessment (KERA)
The County received a $225K FEMA Hazard Mitigation grant, requiring a $75K local match, with two deliverables:
- Update the volcanic risk/vulnerability assessment in the County Multi-hazard Mitigation Plan
- Develop volcanic risk mitigation actions
Pacific Disaster Center (PDC)
The Pacific Disaster Center offered to provide the updated risk assessment as part of its normal programming, at no cost to the County.
The risk assessment is one of several inputs that will inform long-term (5-10+ years) recovery planning by helping decision makers understand hazard risks via data-based analysis.
Image via PDC: Volcanic Multi-hazard Risk Equation
- A hazard is defined as any agent that can cause harm or damage to humans, property, or the environment. Volcanic hazards include: lava flows, eruptive fissures, cinder cones, pit craters, graben and caldera faults, volcanic gas, and earthquakes.
- A risk is defined as the probability that exposure to a hazard will lead to a negative consequence.
- Vulnerability is the extent to which a person, household, business, community, or other social entity is likely to face negative outcomes from the exposure to environmental hazards and extreme events.
- Vulnerability factors can include housing and transportation, socioeconomic status, access to information and lifelines, and household composition.
County representatives are currently working with PDC to ensure that relevant data points are captured in the assessment to assure accuracy. Upon completion, the Risk Assessment results will be posted to this site.
Learn more about Pacific Disaster Center