The June 27th lava flow, named for the date it began erupting, continues to advance to the northeast of its vent on the flank of Pu‘u ‘Ō‘ō on Kīlauea Volcano’s East Rift Zone. As of Friday, August 22, the front of the flow was 10.7 km (6.6 mi) northeast of the vent.
According to the USGS Hawaiian Volcano Observatory (HVO) Scientist-in-Charge Jim Kauahikaua, the lava flow is not an immediate threat to residential areas or infrastructure downhill of the flow, but could become one in weeks to months if lava continues to advance.
HVO scientists, who mapped the flow during an overflight Friday morning, report that the flow was active along two fronts. The northern branch was advancing northeastward across fairly flat land, while the southern branch had flowed into a ground crack within the rift zone. By tracing the steam issuing from the crack, lava is inferred to have advanced 1.4 km (0.9 mi) over the past 4 days, putting it 3.8 km (2.4 mi) from the eastern boundary of the Wao Kele o Puna Forest Reserve.
The difficulty in forecasting the flow’s exact path is that “downhill of the flow” can be affected by subtle variations in topography (shape and features of the ground surface), changes in lava supply (volume increases or decreases), and where and how lava enters or exits ground cracks along the rift zone.
Kilauea Volcano’s East Rift Zone eruption began in January 1983. Since then, most lava flows have advanced to the south, reaching the ocean about 75 precent of the time. But the northeastward movement of the June 27th lava flow is not unprecedented. Lava flows also traveled northeast of Pu‘u ‘Ō‘ō episodically in 1983-1986 and for four months in 2007, as well as during the past 19 months. The most distal point reached by the Kahauale‘a and Kahauale‘a 2 lava flows, which were active from early 2013 until June 2014, was 8.8 km (5.5 mi) northeast of Pu‘u ‘Ō‘ō.
The June 27th lava flow is advancing through a heavily forested area on Kīlauea’s East Rift Zone. This area of the rift zone is exceedingly hazardous to hikers as it is highly fractured, with numerous, deep ground cracks that are difficult to see because of the heavy vegetation. Another hazard in the area includes methane explosions that occur when lava flows over vegetated land.
The June 27th lava flow is currently within the Kahauale‘a Natural Area Reserve, which has been closed by the Hawaii State Department of Natural Land and Resources (DLNR) due to the ongoing volcanic hazards, and the Wao Kele o Puna Forest Reserve, also closed by DLNR and the Office of Hawaiian Affairs.
HVO continues to closely monitor the June 27th lava flow through increased overflights, satellite imagery, and webcam images, and is keeping Hawai‘i County Civil Defense fully informed about the flow’s location. The public can track the lava flow activity through maps, photos, and daily eruption updates posted on the HVO website at http://hvo.wr.usgs.gov/activity/kilaueastatus.php. Should the lava flow become an immediate threat to residential areas or infrastructure, HVO will begin posting more frequent updates.