Living on Kīlauea — one of world’s most active volcanoes — involves risk, mitigation efforts

Big Island residents who live on Kīlauea, one of the world’s most active volcanoes, know it comes with high risk.

Memories of the destructive and unprecedented 2018 lower East Rift Zone eruption in Puna are still fresh. Recovery is still ongoing five years after the lava flows wiped out several communities, including Kapoho, Vacationland, Lanipuna Gardens, most of Leilani Estates and parts of Pohoiki.

And itʻs not a matter of if another eruption will happen in Kīlauea’s East Rift Zone, but when.

Just since 2018, there have been five more eruptions, including the one that started Sept. 10. The all have been confined to the summit caldera within Hawai’i Volcanoes National Park and posed no threat to life or property

But East Rift Zone eruptions can occur frequently. Since 1950, there were long-lived eruptions at Maunaulu from 1969-71 and 1972-74 and Pu‘u‘ō’ō from 1983 to 2018.

The eruption at Pu‘u‘ō’ō, which scientists divided into 61 episodes of activity, destroyed 215 structures and buried nearly 9 miles of highway with lava as thick as 115 feet. It ended just before the 2018 eruption began. That eruption also destroyed Kalapana in 1990 and was the longest and most voluminous known outpouring of lava from Kīlauea’s East Rift Zone in more than 500 years.

Shorter-lived eruptions occurred on the East Rift Zone 12 times between 1955 and 1980. The 1960 eruption destroyed a previous community at Kapoho. There also was a lava flow in 2014-15 that threatened Pāhoa.

The volcano’s Southwest Rift Zone, which is less populated than the East Rift Zone, has not been as active during the past two centuries, but eruptions can still happen there.

The most recent Southwest Rift Zone eruptions were brief. An event in 1974 lasted for less than a day and an eruption in 1971 lasted for just five days. However, longer-lived vents are possible in the area. The Maunaiki eruption lasted almost a year from 1919-20.

While the 2018 event represented the largest summit collapse and lower East Rift Zone eruption in the past 200 years, it also fit a pattern of Kīlauea’s past behavior. What was unprecedented was the impact, which was due to the development growth in that part of the Big Island.

So with more people now living, working and playing there, what works and does not work when it comes to mitigating the high risk of inevitable future eruptions?

While structural engineering and construction methods can be adapted to reduce damage from other natural disasters such as hurricanes and earthquakes, they do not help with lava flows.

“There is no building code or regulation that will save a house from being inundated by 30 feet of lava,” said Cyrus Johnasen, executive assistant to Hawai‘i County Mayor Mitch Roth. “It simply doesn’t exist.”

Instead, mitigation strategies should prioritize reducing buildings and infrastructure in those high-risk zones while ensuring residents are well-informed and prepared for potential disasters.

“The best thing we can do is discourage future investments in high-risk areas,” Johnasen said.

The county continues to advocate for its voluntary housing buyout program, funded by the U.S. Department of Housing and Urban Development. The program is dedicated to acquiring properties affected by the 2018 eruption to minimize the return of residents to those high-risk areas.

To date, 275 properties out of 800 applications have been closed on, with nearly $55 million distributed to people affected by the eruption. The primary objective is to keep those properties unoccupied by new homes or businesses that could be vulnerable to future eruptions.

“It’s our hope to help as many people move out of the highest risk areas as possible,” Johnasen said.

However, it’s not feasible to ask all people to abandon their properties and pick up their entire lives to move somewhere safer, especially when there are neighborhoods in lava zones 1 and 2, the two highest areas at risk of eruption, that have been there for more than 50 years.

“Recognizing that folks want to continue living there, how do we support them in sustainability and resiliency?” asked Hawai‘i County Councilwoman Ashley Kierkiewicz, who represents the area devastated by the eruption. “Some folks think it’s too big of a challenge, but I just see tremendous opportunity there to demonstrate what’s possible.”

She’s always thought Puna can be a model of sustainability and resilience and the 2018 eruption offers the moment to rise to that occasion. The question becomes how can development change to better adapt to the reality of future eruptions and even other natural disasters such as hurricanes and wildfires.

Kierkiewicz suggested ideas such as building more modular homes that could be moved out of the area of a disaster and testing other nontraditional materials for construction, such as eucalyptus, which the island has a readily available supply. That would include taking a look at the county’s building codes and how they could be changed to accommodate such construction and other ideas.

The Hawai‘i County Civil Defense Agency emphasizes disaster preparedness related to eruptions.

“They work closely with residents to enhance evacuation and emergency response procedures, aiming for a streamlined and efficient response in the event of the next eruption,” Johnasen said.

Kierkiewicz also has been working with police, fire personnel, Civil Defense officials and Roth’s office to talk about infrastructure, emergency communication and evacuation plans. Communication plays a pivotal role in responding to natural disasters, especially on the Big Island where no one-size-fits-all approach works to reach all residents simultaneously.

The County is establishing comprehensive communication plans for the next disaster.

It has developed templates for the most critical hazards so messages can be dispersed with minimal delay and is using the Integrated Public Alert Warning System to support messaging to cellphones, radio and TV in combination with the outdoor alert siren system to alert people about emergencies of all types, including natural disasters such as eruptions and wildfires anywhere on the island.

That includes eruptions of the island’s other two active volcanoes, Mauna Loa and Hualālai.

Mauna Loa erupted in November of last year for the first time in nearly 40 years. Lava flows in parts of Mauna Loa’s Southwest Rift Zone, on which communities such as Ocean View, Pāhala and Nāʻālehu are located, can flow so fast because of the volcano’s steepness that it can have major impacts within a matter of hours instead of days.

On June 1, 1950, a fissure erupted high on Mauna Loa’s Southwest Rift Zone and within three hours, ʻaʻā lava flows had crossed the main highway on the west coast of the Big Island.

That’s not to say lava can’t flow quickly down the slopes of Kīlauea. During the 2018 eruption, lava in the channel from Ahuʻailāʻau, the most active vent during the eruption and previously called Fissure 8, was clocked at speeds of up to nearly 20 miles per hour.

Hualālai is not nearly as active as Mauna Loa or Kīlauea. It last erupted in 1801, but is considered likely to erupt again and potentially dangerous as resorts, homes and commercial buildings have been built on its flanks during the past several decades.

An intense swarm of more than 6,200 earthquakes in 1929, most likely caused by an intrusion of magma beneath the volcano, rattled the area around the mountain for more than a month. Two large earthquakes, both about 6.5 in magnitude, destroyed houses, water tanks, stone fences and roadways.

Civil Defense also uses the voluntary Everbridge system to push messages out via social media, including on Facebook, X (formerly Twitter), and phone calls and texts for those who sign up.

“We always strive to meet the five [Federal Emergency Management Agency] mission goals of prevention, protection, mitigation, response and recovery,” Johnasen said.

The county is putting robust strategies in place as well to ensure disaster preparedness plans are communicated properly to the public. That includes updating its Multi-Hazard Mitigation Plan, a Federal Emergency Management Agency requirement, this fall. The plan includes mitigation projects based on and prioritized by the county with input from residents.

Emergency officials also work closely with experts at the Hawaiian Volcano Observatory when eruptions happen. As the science progresses to understand the workings of the island’s volcanoes, especially Kīlauea, the county benefits from that knowledge and experience to help it better forecast what hazards could impact a community and prepare them in the event evacuations are necessary.

“Preparedness saves lives,” Johnasen said.

He said community groups have demonstrated incredible resilience and support during disasters, including the 2018 eruption, and the county understands the immense strength of community organizations in providing relief.

“We did that during the eruption,” Kierkiewicz said. “We started ‘The Hub’ and that catalyzed into … an islandwide network of resilience hubs through Vibrant Hawai‘i that is still thriving and growing today. That’s huge.”

The county is partnering with Vibrant Hawai‘i to maintain that network of resilience hubs for education, preparedness and connectivity while meeting the daily needs of its members. Community Emergency Response Teams also are in direct communication with Civil Defense and communities to provide training and support.

Work is also underway now to expand Civil Defense to a 24-hour operation so personnel is present to monitor activity and provide timely alerts when necessary. That also would mean backup support for the State Warning Point, a statewide emergency communications center managed by the Hawai‘i Emergency Management Agency.

“We’ve learned a lot from past disasters, particularly regarding the coordination of crucial assets during those pivotal initial weeks,” Johnasen said. “We become more resilient by learning from our past mistakes, embracing and partnering with community organizations that lead in resilience and recovery, and improving the way we communicate with everyone on the island during times of need.”

No one knows if a home they build or buy or community infrastructure in a high risk area such as lava zone 1 will be destroyed. That’s a risk individuals and community’s on an active volcano must take into consideration.

The Hawaiian Volcano Observatory, which is focused on the science of volcanoes, aims to keep people and the community educated about the hazards so they can make more informed decisions.

Hawaiian Volcano Observatory Scientist-in-Charge Ken Hon said volcanoes are pretty constant, unlike hurricanes, wildfires and other natural disasters that come and go, so the hazard doesn’t change much through time.

What does change is the risk — the exposure to the hazard — and that’s usually because of an increase in population. As more infrastructure and homes are built in those high risk areas, the potential losses become greater.

“That’s generally the pressure that puts people into areas where they’re exposed to a hazard,” Hon said. “Now, whether we should be in those areas or not is really up to people as a whole and how we decide to create government structures that support the community as a whole.”

Kierkiewicz said during a recent Council meeting that folks often ask why people continue to live in lower Puna knowing one of the world’s most active volcanoes is in their backyards. For starters, it’s one of the most affordable places left to live in Hawaiʻi.

Homes in Puna sell for half or even sometimes less than the median price of a home in Honolulu, which has topped $1 million. The district also offers a country-like lifestyle and a relatively short commute to Hilo for work and services.

It’s one of the fastest growing areas in the state. It was anticipated in 2022 that within the next 12 years, Puna will grow by about 42,000 residents, nearly double the current population.

The region is also beautiful — the word “puna” means to spring forth. The Councilwoman, who was born and raised on the Big Island and lives on Kīlauea’s East Rift Zone in Hawaiian Paradise Park, said there’s incredible, creative energy in the region and the lifestyle is bar none.

There also are deep ancestral and cultural ties to that area for many.

“So for generations, people have lived in Puna with Tūtū Pele,” Kierkiewicz said. “They’ve recognized where they are and they are able to work in concert with ʻāina and what happens.”