HONOLULU, Hawaii: Officials are concerned that a major eruption of the Mauna Loa volcano on the Big Island of Hawaii could produce a lava flow on a key highway, blocking the main route connecting two sides of the island.

The molten rock could make the road impassable and force drivers to find alternate coastal routes in the north and south, adding hours to commute times.

US Geological Survey scientists reported that lava's path is unpredictable and could change course, and the slow-moving flow, which could stop completely and spare the highway, was coursing about 2.7 miles from the road, as of last week.

Meanwhile, the state's Department of Transportation reopened a lane across Nanue Bridge that was closed for repairs, and began removing potential traffic obstacles on the northern coastal route.

Hawaii County Councilor Susan L.K. Lee Loy, who represents Hilo, one of the island's major harbors, and parts of Puna, expressed her concerns about large trucks traveling across aging coastal bridges.

"It is going to take a lot to rethink how we move about on Hawaii Island," she said, as quoted by Reuters.

Outrigger Kona Resort and Spa plans to provide rooms at a Kailua-Kona hotel, so its dozen or so Hilo-based employees can avoid the long commute five days per week.

A shutdown could also affect a major astronomy research program at the summit of Mauna Kea, a 13,803-foot peak next to Mauna Loa, which has some of the world's most advanced telescopes.

Rich Matsuda, associate director for external relations at W.M. Keck Observatory, said they may need to adjust staff schedules and house workers at a facility on the mountain so they can avoid commuting, as there is a chance the lava flow could head directly across the lower part of Mauna Kea Access Road, preventing workers from reaching the summit.

Geologists at the Hawaiian Volcano Observatory said if Mauna Loa follows historic patterns, the eruption that began this week will continue for one to two weeks.

Meanwhile, US Rep. Ed Case and US Rep. Kaiali'i Kahele sent a letter to President Joe Biden, which said that Hawaii County would need "immediate help" to keep island communities safe if lava flow blocks the highway.