In April 2018, seismic sensors at the Hawaiian Volcano Observatory on the Island of Hawai‘i signaled the movement of magma (subterranean lava) inside Kīlauea Volcano.
Then, suddenly, on April 30, the glowing vent within Pu‘u ‘Ō‘ō cone collapsed. Soon afterward, the lava lake at Halema‘uma‘u crater in Hawai‘i Volcanoes National Park (HVNP) began to drop. And, on May 3, fissure eruptions broke out miles downslope in the Leilani Estates subdivision to the east.
The awe-inspiring and heartbreaking eruption of fiery fountains and molten rivers near the coast continued for four months. Small, daily earthquakes—60,000 of them between April 30 and August 4—shook up those who live and work around Volcano Village and HVNP. The largest measured 6.9 on the Richter scale. The park closed for safety reasons–some roads developed steaming cracks, building walls fractured, and water pipes burst. No staff or visitors were hurt.
Now, after rangers and engineers have repaired roads, hiking trails, campgrounds, and backcountry areas, almost all of HVNP (a UNESCO World Heritage Site and an International Biosphere Reserve) is again open and welcoming visitors.
Hawai‘i’s largest and youngest island, known to most people as “the Big Island,” gained about 875 acres of new land–jagged lava-rock coast and black-sand beaches. While most parts of the park remain as they were before the 2018 eruption, with the same forests and lava plains, other areas of the park are forever altered. The most dramatic change to the park’s landscape is the astoundingly wider and deeper summit crater, Halema‘uma‘u.
The summit caldera used to be primarily a flat lava plain surrounding Halema‘uma‘u crater. Now the views and sense of place have changed. Quakes have carved new escarpments into the caldera. Halema‘uma‘u’s volume has increased from about 75 million cubic yards to about 1.2 billion. It is no longer immediately fathomable as a whole geologic structure.
“There’s this duality, because not only is the volcano a source of destruction, but it’s also a crucible of creation,” park Ranger Dean Gallagher said during a guided hike along the Crater Rim Trail that partly encircles Halema‘uma‘u. He and other rangers lead informative hikes here and elsewhere in the park. “I want to give you a Hawaiian perspective,” he continued, describing how volcano goddess Pele “wipes the slate clean” and creates more land, and then her sister Hi‘iaka foments new growth.