Hawaii island Civil Defense officials long ago gave up on the idea of trying to halt a river of 2,100-degree molten lava heading along a path of destruction toward Pahoa.

But they’re certainly listening to ideas coming out of the lower Puna district about how to get both people and supplies in and out if 8,500 residents get trapped behind the lava spewing from Kilauea Volcano. In the next few weeks, the flow is expected to overrun Highway 130, the main road.

At the suggestion of Puna residents, Civil Defense officials have been searching for plantation-era cane haul roads that were used as improvised runways by fearless crop-dusters.

The idea would be to restore the abandoned roads for small planes to bring in supplies to lower Puna. But so far, the old roads can’t be found.

One improvised landing strip off of Highway 130 "is no longer visible," said Darryl Oli­veira, head of Hawaii County Civil Defense. "We’ve heard rumors of another one in Kala­pana, but we couldn’t find anything."

However, he said, using parks, sports fields or other centrally located open areas for helicopter trips remains a possibility.

And Civil Defense officials continue to explore the idea of running small boats out of Isaac Hale Beach Park, despite often bumpy ocean conditions and the need to involve the Coast Guard, the state Department of Land and Natural Resources and county agencies.

They’re also talking to the Army Corps of Engineers on Oahu about the possibility of building an emergency bridge across lava-covered sections of Highway 130 — once the lava has cooled and hardened enough.

"We’re not going to put people in harm’s way," Oli­veira said. "We’re not going to build a bridge and let cars drive over hot lava."

Dino Buchanan, spokes­man for the Army Corps of Engineers, said talks continue with Civil Defense officials but that the idea remains untested.

Asked whether Army bridge-building technology has ever been tried over cooling lava, Buchanan said, "No, nothing, zero. Everybody’s trying to figure out what to do and how best to do it."

At twice-weekly community meetings about the lava flow that began June 27, there’s now less and less talk about trying to stop it or even change its direction.

But Byron Matthews, a 34-year-old Hilo Realtor who lives in Puna and has lots of family there, does not understand why officials will not consider bombing Kilauea to blow open an opening that theoretically could divert the lava out to sea.

Matthews grew up watching lava in Puna and has seen military fighter jets drop practice bombs over Hawaii island’s military Poha­ku­loa Training Area.

"I don’t know if it would be a military strike," Matthews said, "but it would have to be a bunker-buster to knock out a section near the source. If it was heading toward Hilo, they would consider that, but because it’s Pahoa they’re not even considering it. It seems to me like they’re just writing it off. If they can so something, they should at least try."

Bombing Hawaii island’s other volcano has been tried before, according to a study of efforts to stop or divert lava for the U.S. Geological Survey, which continues to track the latest flow.

"The U.S. Army Air Corps carried out aerial bombing of lava flows from Mauna Loa in 1935 and 1942; the results were considered inconclusive, because the lava flow stopped at about the same time as the bombing operations," according to the report.

During a 1986 eruption in Kala­pana that destroyed houses, firefighters also tried spraying water on advancing lava to try to divert it around a home, "but the attempt failed because of the volume of lava," according to the USGS study.

Oliveira, Hawaii County’s former fire chief, was one of the firefighters who tried to push back against advancing lava in Kala­pana with a fire hose.

"We were wasting water and just creating a sauna," he said. "That had absolutely no effect."

Even if it were possible to change the direction of lava, Oli­veira said it could end up becoming a different area’s problem.

"Any breach in the tube system might just redirect it to Hawaiian Acres," Oli­veira said. "It might just make another problem in a different area of the community."

And he said it’s physically impossible to pump enough sea water to try to cool the current flow.

"You’re miles downhill and fighting against gravity to get it up to the elevation it’s at," Oli­veira said. "For every 1 foot of elevation, you need 0.5 pounds of water pressure. In concept it sounds doable. In practicality it’s highly unlikely."

Oliveira has heard stories from the late 1950s about the Fire Department’s efforts to use dirt and cinder as a temporary barrier to change the direction of lava flowing through Kapoho.

"The consensus was that no barrier could prevent the flow from advancing," Oli­veira said. "All it did was delay it. It’s just temporary protection."

For the current flow headed toward Pahoa, Hawaiian Electric Light Co. plans to use untested insulation to temporarily protect power poles in the lava’s path.

But Oliveira said it will only delay the inevitable.

He quoted firefighters who came before him who tried to stop the advance of lava spewing out of Kilauea:

"Lava’s going to do what lava wants to do," Oli­veira said. "You can’t stop it."