November 21, 2001
A weekly feature provided by scientists at the Hawaiian Volcano Observatory.
The ghosts of holiday eruptions past
Every year about this time, the HVO staff asks the question: Will the volcano behave over the holidays? Given the amount of volcanic and seismic activity on this island, our holidays are bound to be disrupted now and then. The busiest holiday season in recent memory occurred during the current eruption of Kilauea, when lava flows cut a swath through the old Hawaiian village of Kapa`ahu on Thanksgiving Day 1986, then shifted 3 km (2 mi) to the east and destroyed 15 houses in Kalapana just before Christmas.
How many readers remember when the quickest way to get from Volcano to the black sand beach at Kaimu was to drive down Chain of Craters Road through the national park? Once you reached the coast, you sped past the beautiful picnic area at Kamoamoa and the visitor center at Waha`ula, carelessly assuming that you had all the time in the world to go back and explore these places thoroughly. Then you were out of the park and passing the turnoff to Royal Gardens subdivision on the left and the dirt road to Punalu`u (Queens Bath) on the right. A cluster of houses appeared on the inland side of the highway at Kapa`ahu, but you hurried on to the beach. All that changed in late 1986.
Kapa`ahu had forewarning of what was to come. `A`a flows from episodic eruptions of Pu`u `O`o spilled over the pali into nearby Royal Gardens several times in 1983-84, destroying 16 houses. In April 1984, an `a`a flow took a more easterly course and destroyed three houses on the northwestern edge of Kapa`ahu. None of these flows reached the highway, and the damage they did was limited, because most eruptive episodes lasted less than a day.
In July 1986, the eruption shifted to Kupaianaha, a new vent 3 km (2 mi) northeast of Pu`u `O`o. The activity changed from episodic fountaining to continuous, quiet effusion, which promoted the development of lava tubes and allowed lava to move far from the vent before cooling and stagnating. By November 1986, tube-fed flows were slowly advancing down Pulama pali toward Kapa`ahu.
The day before Thanksgiving was sunny and clear, but a noxious cloud of black smoke settled over Kapa`ahu as lava crossed Highway 130, setting fire to the asphalt. The crackle of burning vegetation was punctuated by low booms from methane explosions near the edge of the flow. One of these explosions lobbed a football-sized chunk of rock onto the highway, startling the head of civil defense (now our mayor), who sprang into action and hustled onlookers away.
By nightfall, lava had overrun five houses above the highway and had flowed through the wrought-iron gates of Pacific Paradise Ocean Front Estates across the road. This subdivision had only two houses; both were destroyed by early Thanksgiving Day.
A historic structure within the subdivision lingered much longer. The ruins of Father Damien's Church, built in about 1870, escaped the first round of lava flows through Kapa`ahu. The high walls of the church, hidden beneath a tangle of monstera vines and shaded by huge plumeria trees, became a popular oasis for those of us working on the sweltering flows nearby. Unlike most structures destroyed by this eruption, the concrete walls of the old church were gradually buried, not burned, and finally disappeared beneath the rising tide of pahoehoe in early 1988.
The flows skirted Punalu`u, leaving this lovely spot untouched for a few more months, but filled in the shallow tidal pools at the shoreline beyond. Lava entered the ocean the day after Thanksgiving for the first time since 1973 during the Mauna Ulu eruption.
A disruption in the tube system near the vent granted Kapa`ahu a temporary reprieve in early December but diverted lava toward Kalapana, where a week before Christmas, 14 homes burned in a single day.
Currently, the county's lava-viewing road ends at the site of Kapa`ahu, and lava is entering the ocean in the same place it first did in 1986, though the shoreline has extended seaward 280 m (900 ft) in the intervening years. For now, we can give thanks that no inhabited houses have been destroyed in the last decade, but we should not become complacent about the future.
Eruptive activity of Kilauea Volcano continued unabated at the Pu`u `O`o vent during the past week. Lava moves away from the vent toward the ocean in a network of tubes and descends Pulama pali in several separate tubes. Surface flows are observed above the pali and at various places along the trace of the Kamoamoa tube system. Lava continues to enter the ocean in two locations: Kamoamoa and the area east of Kupapa`u. The entry at Kupapa`u stopped some time last week, and the flow approaching the coast in the same area has stalled.
The public is reminded that the benches of the ocean entries are very hazardous, with possible collapses of the unstable new land. The steam clouds are extremely hot, highly acidic, and laced with glass particles. Swimming at the black sand beaches of the benches can be a blistering or even deadly venture.
Updated: November 26, 2001 (pnf)