As lava continues to threaten the lifeline to Hawaii island’s lower Puna District, county and federal officials are locked in a dispute over how to build an escape route through Hawaii Volcanoes National Park.

County officials are paying the $7 million to $10 million estimated cost to rebuild 5.4 miles of Chain of Craters Road that have been repeatedly buried by lava on federal land inside the national park. And Hawaii County Mayor Billy Kenoi insists that the people of lower Puna need a two-lane, paved road for the hours-long trip out of Puna to make their way back to and from Hilo once lava crosses Highway 130 and traps 8,500 residents.

So county crews are preparing two lanes of existing paved highway on 1.2 miles of Chain of Craters Road on county land near the lava viewing area at Kalapana. And state road crews plan to rebuild two lanes of 2.14 miles of Chain of Craters Road on state land in between Kalapana and the entrance to Hawaii Volcanoes National Park.

But the U.S. Department of Interior’s Office of Environmental Planning insists that the 5.4 miles of rebuilt Chain of Craters Road on federal land will have to narrow to one lane of unpaved road to protect both sensitive Hawaiian archaeological sites and endangered species such as the nene goose, the official state bird, said Cindy Orlando, superintendent of Hawaii Volcanoes National Park.

"There will be impacts," Orlando said. "I hope people remember that this is a national park and we need to ensure the impacts are lessened as much as possible. With one lane, we do not expect any significant impacts."

Traffic through the park will move one way out of Puna in the morning — and the opposite direction into Puna in the afternoon, she said. The restored sections of Chain of Craters Road also will include pullouts every 100 yards so slower-moving vehicles can let those behind pass.

But the Department of Interior’s insistence that Chain of Craters Road be rebuilt as only one lane through Hawaii Volcanoes National Park is not going down well with Kenoi — especially because the county is paying for the work to be done on federal land, according to his spokesman, Kevin Dayton.

"The mayor is insisting that this must be a two-lane road," Dayton said. "What is required to serve the people of Puna is two lanes. And that is what the county will be working toward."

For Tom Henneman, 65, of Nanawale, one lane of traffic through Hawaii Volcanoes National Park will be "one huge bottleneck" for him.

"It’s already going to be an extra 37 miles for me to get to Hilo," Henneman said. "With one lane, it’s going to take me a couple of hours stuck in traffic for what is usually a 25- to 30-minute drive."

The rebuilt Chain of Craters Road would represent the third escape route out of Puna.

If lava renders Highway 130 useless as expected in the next few weeks, the rebuilt portions of the 19-mile-long Chain of Craters Road would reopen an estimated three months after county and state road crews already open evacuation routes, one they carved out of abandoned dirt roads called Railroad Avenue and another that goes by various names including Beach Road and Old Government Road.

County officials estimate the cost of rebuilding Railroad Avenue and Old Government Road at $2 million. State transportation officials could not immediately provide a cost estimate for rebuilding the state’s portion of Chain of Craters Road.

Dayton said the county’s cost for work that began Tuesday on its 1.2-mile stretch of county road will be minimal because it mostly involves ensuring that shoulders along the existing highway are cleared.

But both federal and county officials say that the federal government might repay Hawaii County for the $7 million to $10 million it will front for the cost to rebuild Chain of Craters Road on federal land.

"Once the lava hits Highway 130, that triggers the disaster per se and the county will be eligible for some federal reimbursements," Orlando said.

Whether it’s one lane or the two lanes that Kenoi wants, re-establishing the lava-covered portions of Chain of Craters Road will pump an estimated 4,000 more vehicles through the park every day in addition to the vehicles that are normally there. In August, 4,890 people on average visited every day in August. That number represented a 10 percent jump from August 2013.

With the old sections of Chain of Craters Road reopening, Orlando will need more staff to deal with more visitors and more traffic.

And she’ll need extra armed law enforcement rangers to protect ancient archaeological sites that have been off-limits — and to enforce a ban on outsiders who will suddenly have access to fishing grounds reserved for Native Hawaiians who live in and around Kalapana.

"Our law enforcement presence is going to have to go way up because we don’t want illegal fishing along the coast," Orlando said. "We’re going to have to patrol it regularly so we don’t have illegal activities down there. We’re also going to require a lot more traffic management, and that 19 miles (of Chain of Craters Road) is also going to have increased maintenance and operating costs."

If the flowing lava continues to set fires closer — or within — the park, Orlando also will have to staff a fire command center.

Orlando hopes to get more rangers and specially trained law enforcement rangers from other national parks in Hawaii or from the mainland.

"And we still have to take care of the 5,000 visitors we get every day," she said.

In the meantime, Kenoi will continue to push for an extra lane for Puna residents trying to get in and out of Puna during an active lava flow.

"In the event that Highway 130 is cut by lava and access is cut," Dayton said, "Chain of Craters Road has to be a two-lane road for the people of Puna."

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