COURTESY HAWAIIAN VOLCANO OBSERVATORY The newest Big Island lava flow, the third since July 21, started just before noon Tuesday. It is being fed by overflow from a nearby channel.

All eyes are on lava flow

Big Island officials attempt to assuage the public's concerns

HILO » Big Island lava flows pose no immediate threat to populated areas, officials said yesterday, but they were vague about what they would do if the threat increased.

"We take this, obviously, very seriously," Mayor Harry Kim said in a news conference.

Fire Chief Darryl Oliveira said his department makes a helicopter flight over the flows every day, reporting the location of the tip of the flow and whether any brush fires are igniting.

Asked what the county would do if lava threatened to cut Highway 130, the sole road to Pahoa, Kim said it would depend on information from the Hawaiian Volcano Observatory.

Pressed for an answer on whether Chain of Craters Road through Hawaii Volcanoes National Park would be extended as an alternative route if Highway 130 is cut, Kim said that is a possibility to be considered at the time.

If a lava flow cut Highway 130, it would also cut electric transmission lines running along the highway from Puna Geothermal Energy, which supplies a fourth of the Big Island's power.

Hawaii Electric Light Co. has enough backup generation capacity that there would be no interruption of power to the island, Kim said.

Those were some of the worst-case scenarios that worry the public in the lower Puna area.

Kim objected to a statement that current flows are pointed at Pahoa, but a Puna resident told him that was a fact. Kim said he objected because there seemed to be a conclusion that damage would come to Pahoa.

Jim Kauahikaua, head of the Hawaiian Volcano Observatory, gave a slide presentation showing that present flows are contained in an area nine miles uphill from Pahoa.

Three flows have taken place since July 21, the longest being five miles, and all solidified, he said. A fourth is now active but has miles to go before it even matches previous flows, he said.

All of the flows have been open aa, which loses its heat and hardens. If the flows change to pahoehoe in a closed tube, they could flow a lot farther, Kauahikaua said.

He showed a computer simulation of where terrain might direct a long flow if it acted like water. Observers have long known that lava frequently does not act like water.

Still, there was no comfort in the simulation showing a maze of hypothetical streams paths, many possibly headed toward heavily populated subdivisions.

A benchmark is the time lava would need to reach the sea. In 1986 it needed four months to travel six miles southeast to the water. The implication was that a flow in the other direction, toward the populated northeast, could take more time flowing a greater distance over more gently sloping ground.