MAUNA LOA, Hawaii >> Mauna Kea has been the popular choice for Hawaii island visitors who want to drive to the top of a 13,800-foot high volcano.

But with the access road shut down due to protests against the building of the Thirty Meter Telescope, some are now turning to Mauna Loa — and a single-lane, 17-mile roadway off the Daniel K. Inouye Highway that cuts through lava fields and leads to Mauna Loa’s two observatories located at the 11,135-foot level, and the Mauna Loa Observatory Trail that leads to the summit at an elevation of 13,679 feet.

The 17-mile roadway, owned and managed by the Department of Land and Natural Resources, is near the Mauna Kea Access Road on the opposite side of the highway.

“We’re seeing a heavy increase in traffic in the evening,” said Aidan Colton, outreach manager and scientist at the Mauna Loa Observatory, which falls under the National Oceanic and Atmospheric Administration (NOAA). “People are walking up the (observatory) road while we’re doing measurements at night. They’re using our location as an alternative to Mauna Kea for stargazing and sunrises and sunsets.”

With no public restrooms, visitor center or anyone to ask for help, visitors are left to figure things out for themselves.

Unlike Mauna Kea, which only requires a 4-wheel-drive vehicle to get to the top, Mauna Loa is known among backpackers as an arduous climb over lava requiring the fitness, stamina and ability to withstand the high altitude and cold, the proper clothing and boots, and enough food and water.

The reward is the view of its caldera, amazing views of the island, including Mauna Kea and, of course, bragging rights for those who make it to the top.

But more and more nonhikers or casual day hikers are venturing out to Mauna Loa and discovering the lack of facilities.

One glaring sign of an increase in visitors is the white toilet tissue residue on the black lava fields found along the edge of the roadway.

“It’s really 95% of it is due to (activity) in the last few months,” Colton said.

“We are trying to work on a solution to this sudden increase in popularity at this site,” said Jackson Bauer, DLNR’s Division of Forestry and Wildlife Hawaii Island Na Ala Hele trails and access specialist said. “This area is attracting a different user group (sightseers vs. backpackers) and therefore different understandings and expectations on how to care for natural areas.”

He said the agencies responsible are “working together on various short- and long-term solutions.

“We are trying to hire a portable toilet to be stationed at the end of the road, however, no portable toilet companies are willing or have the capacity to drive up the long road and service it weekly,” he said.

On a recent Sunday, various visitors drove up during the day to the observatory, filling the small parking lot, while others parked in the few spots on the side of the roadway. Most stopped to read an informational sign put up by the National Park Service about the volcano, including a map and warnings about the dangers of the mountain, such as altitude sickness.

A couple from Switzerland, who wanted to reach the top, hiked a few hours, but came back down due to time constraints; two young men said they made it to the 12,000-foot elevation but were returning because one was experiencing headaches; a couple in a rental car arrived just before 2 p.m., appeared to be preparing for backpacking.

DLNR officials say they have plans to install a sign at the beginning of the road to notify users of the lack of facilities. DLNR’s website details this at hawaiitrails@hawaii.gov

Colton said in past years during heavy snow roughly 200 cars come up and observatory personnel had asked to put up a gate at the bottom of the road, but DLNR said no.

Currently, observatory personnel are measuring air quality to ensure the increased number of cars isn’t causing a problem. “We’re trying to maintain a clean buffer zone,” he said, but acknowledged that the mountain is for everyone.

While the observatory runs tours, it is shortstaffed and not offering any tours for the rest of the year.

The weather can change quickly on the mountain and can get down to freezing temperatures.

Colton said some people do get lost hiking down on the wrong trail, and end up down past the observatory where they park. One man was walking up the main road, while his wife sat by the side of the road. He took the wrong path and ended up two to three miles away from his car.

Jessica Ferracane, spokeswoman for the Hawai‘i Volcanoes National Park, which manages most of the volcano (but not the beginning of the Observatory Trail and the access road) said, “We have not seen an increase in search and rescue or in back-country permits.”

But, Ferracane said, Mauna Loa is difficult for various reasons, including the altitude. Hiking to the summit is not for your average day hiker, but for seasoned backcountry hikers, she said.

“It’s an extremely grueling hike,” she said. “Many are ill-prepared for going to the summit. “

Anyone interested in climbing Mauna Loa is encouraged to refer to the following backcountry planner: 808ne.ws/2ptAf1Z

The following is a map for planning a Mauna Loa hike: 808ne.ws/2QzvJKa