UPDATE: USGS Monitoring Potential Lava Flow Threat to Homes

The United States Geological Survey’s Hawaiian Volcano Observatory announced today that if a June 27th lava flow continues to advance on its current trajectory, it could become a threat to residential areas or infrastructure “within weeks or months.”

HVO Scientist-in-Charge Jim Kauahikaua explained that the flow is not an “immediate threat,” but “could become one” if it continues on its current path.

As of Friday, August 22, the front of the flow was 10.7 km (6.6 mi) northeast of its vent on the flank of Pu‘u ‘Ō‘ō on Kīlauea Volcano’s East Rift Zone.

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.

As USGS scientists explained today, “The difficulty in forecasting the flow’s exact path is that “downhill of the flow” can be affected by subtle variations in topography, changes in lava supply, and where and how lava enters or exits ground cracks along the rift zone.”

The USGS statement goes on to explain that since Kilauea Volcano’s East Rift Zone eruption began in January 1983, “Most lava flows have advanced to the south, reaching the ocean about 75% of the time.”

The northeastern path of the June 27 flow makes it unique, though not without precedent, the scientists explained.

“Over the last two almost two years, there have been flows in this general area,” Kauahikaua said. “They haven’t gone into the ocean since 2013, and most of the activity has been up to the northeast of Pu‘u ‘Ō‘ō, which puts flows moving toward more easterly subdivisions. This is just the latest of those flows and it’s going just a little bit farther south than the previous ones did. It’s also narrower, so it’s moving a bit faster.”

The June 27th lava flow is currently within the Kahauale‘a Natural Area Reserve, which has been closed by the 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 HVO has already increased its observation of the current flow.

“Up until about a week or so ago, we were only looking at it every two weeks, but we were getting a few satellite images in between,” Kauahikaua explained. “Probably our biggest gap in satellite images came when the Tropical Storm came through a couple of weeks back.

“We’re getting several pieces of information per week, and because of the continued movement of the flow, we are going to fly again tomorrow, and then depending on what we find, we may fly again on Monday to track this a little more closely,” Kauahikaua continued. “It’s in a very difficult area to access on the ground so we need to do it by air.

Lava flow activity can be tracked via HVO’s 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.

Big Island Now will continue to update this story as more information becomes available.