With the recent downgrade of the volcano alert level for Kilauea’s June 27 lava flow that has been threatening the Pahoa area, it’s interesting to take a look back at the 1880-81 Mauna Loa lava flow and the threat that it posed to Hilo.
On the evening of Nov. 5, 1880, people in Hilo and at the Volcano House Hotel at the summit of Kilauea noticed a glow on Mauna Loa — produced by an eruption located northeast of the volcano’s summit. A vent at about the 10,500 feet elevation produced one lava flow that moved to the southeast and stalled about 1.5 miles from Highway 11 near Kilauea caldera. A second vent, immediately downslope of the first, erupted a pahoehoe lava flow that advanced to the northeast toward Hilo.
By January 1881, the northeast flow was estimated to be about 18 miles from Hilo. This flow was of interest to Hilo residents, but not a big concern. However, by April, the flow had split into three branches in the vicinity of what is now Kaumana City, a subdivision at the upper Hilo city limits, and advanced to within 7 miles of the town. By the beginning of July, a single branch was only 2.5 miles from Hilo.
The flows were initially difficult to access. But by July, the flows had moved close enough to Hilo that residents and visitors alike were frequently trekking up to the flow to watch its progress. They observed that the pahoehoe would advance very quickly as narrow fingers for short periods of time and then stall, only to repeat the process a few hours or days later. Astonishing stories of narrow lobes of lava advancing hundreds of feet in a few hours were common.
Observers would occasionally note that the lava sometimes occupied a ravine or gulch where water flowed during heavy rains. As the flows got closer to Hilo, people often noticed that warm water seemed to flow out from under the active lava.
As the eruption continued, Hilo residents became alarmed, and many started moving their belongings out of harm’s way. The branch closest to Hilo split into two lobes, with one headed down Alenaio gulch toward the center of Hilo, and the other headed down Kalanakamaa gulch (near and parallel to Mohouli Street) toward the Waiakea Fishponds and Sugar Mill (Wailoa State Park). Everyone feared that the lava would cut through town and enter Hilo Bay.
Just as concern was getting intense, the leading tips of both lobes stalled on or about Aug. 10 with the Kalanakamaa lobe a little more than 1 mile from Hilo Bay. The Alenaio lobe didn’t quite reach Komohana Street. The lava had destroyed only one house near the current location of Kaumana Elementary School. By Aug. 19, the lower portions of the flow were inactive.
This Mauna Loa flow differed from Kilauea’s June 27 flow in two significant ways. The Mauna Loa 1880–81 flow is about twice the length of the June 27 flow, and the Mauna Loa eruption rate was probably higher.
But there were also some similarities. The Mauna Loa 1880–81 and the Kilauea June 27 lava flows were both pahoehoe and were active for about nine months before their threats were reduced. Both flows greatly concerned the people who lived and worked downslope of the advancing fronts, but the flows consumed only a single house before their leading edges stalled. And both flows cut a swath through heavily forested land.
But in the case of the 1880–181 Mauna Loa flow, the open swath it cut through the forest eventually improved travel from Hilo to Waimea and Kona via the saddle between Mauna Loa and Mauna Kea. Years later, the Saddle Road, as it is now known, took advantage of this path. Today, Saddle Road crosses four Mauna Loa flows — the 1880–81, 1855–56, 1899 and 1935 flows — between mile markers 3 and 29.
While the 1880–81 Mauna Loa eruption may have had a beneficial aspect — blazing a trail for Saddle Road — that’s not always the case with active lava flows.
Kilauea activity update
Kilauea’s East Rift Zone lava flow continues to feed three areas of breakouts near Puu Oo. The breakout 4 miles northeast of Puu Oo was the farthest downslope activity observed on Tuesday. The lava flow near Pahoa is no longer active.
There have been no major changes at Kilauea’s summit vent, which continues to host an active lava lake. The lava lake level continues to fluctuate, with the level rising over the past week. The lava level was 120 feet below the rim of the Overlook crater on Thursday.
There were no earthquakes reported felt on Hawaii Island during the past week.
Visit the HVO website at hvo.wr.usgs.gov for Kilauea daily eruption updates and other volcano status reports, current volcano photos, recent earthquakes and more; call 967-8862 for a Kilauea summary update; email questions to askhvo@usgs.gov.
Volcano Watch is a weekly article and activity update written by scientists at the U.S. Geological Survey’s Hawaiian Volcano Observatory.
