Kilauea Volcano Activity Forces Hawaii Trail Closures

Rising seismic activity at Kilauea has prompted the National Park Service (NPS) to close two hiking routes at Hawaii Volcanoes National Park, where scientists are monitoring renewed volcanic activity and potential rockfalls. Announced Wednesday, the restrictions cover a combined 1.3 miles of the Halemaumau Trail and part of the Byron Ledge Trail.

The Hawaiian Volcano Observatory recorded more than 200 shallow earthquakes beneath Kilauea's summit during the preceding week, according to the NPS. A magnitude-3.4 earthquake on September 30 triggered small rockfalls along the northern wall of the caldera.

The U.S. Geological Survey (USGS) issued a volcanic activity notice earlier in the week after renewed spattering appeared at two vents following underground activity beneath the summit. As of Thursday, Kilauea remained at an ORANGE aviation color code, the second-highest level on the agency's four-tier scale.

The designation signals elevated volcanic activity and the possibility of an eruption, or an ongoing eruption presenting limited hazards to aviation, according to the USGS.

Scientists believe an underground intrusion between September 30 and October 1 created new cracks across the caldera floor. They have not established when, or whether, Kilauea's 55th episode of lava fountaining will take place.

The USGS advisory explained that changing volcanic conditions have prevented scientists from reliably predicting the next episode.

"Forecast windows for episode 55 fountaining can no longer be modeled due to changes in conditions," the USGS advisory said.

Authorities also warned that volcanic emissions and airborne fragments could pose health risks to people in the surrounding area. Small, glass-like volcanic particles can irritate the skin and eyes, particularly when wind redistributes material left by recent eruptions.

The USGS advisory described how eruptive material could become airborne again under windy conditions.

"Small glassy volcanic fragments may be remobilized during windy conditions following recent eruptive episodes," the statement added.

The agency also urged people to limit their exposure to the particles because of their potential to cause irritation.

"Residents and visitors should minimize exposure to these fragments, which can cause skin and eye irritation."

The NPS has separately instructed visitors to avoid restricted trails and keep away from unstable cliff edges, which can collapse without warning. The closures are intended to keep visitors away from areas affected by the increased seismic activity and associated rockfall risks.

Kilauea is among the world's most active volcanoes and has erupted dozens of times since 1952, according to the USGS. Its East Rift Zone experienced nearly continuous eruptive activity from 1983 through 2018, a 35-year period that ended amid significant volcanic activity and a collapse at the summit.

Since December 2024, eruptions have occurred intermittently inside Halemaumau crater at the summit. The NPS has reported increased visitor numbers during eruptive episodes as tourists travel to the national park to observe volcanic activity.