A $1 billion radar to track what are expected to be increasingly complex ballistic and hypersonic missile threats to Hawaii may be positioned high on Kaena Point, prompting questions about its visual impact and access to hiking trails.

Public meetings on Oahu held by the U.S. Missile Defense Agency have provided new detail about the powerful radar, which will be constructed either far west at Kaena Point or north at Kahuku Training Area to look out across the Western Pacific.

The Homeland Defense Radar-Hawaii will not be in a dome. Instead, it will have an angular, blocklike shape with a radar face that’s estimated to be 60 to 80 feet tall and 30 to 50 feet wide, said Rear Adm. Jon Hill, deputy director of the Missile Defense Agency.

Ballistic missiles, including those produced by North Korea, travel in an arc, while hypersonic weapons travel faster than Mach 5 (3,800 miles per hour), are capable of maneuvering during the entire flight and can deliver conventional or nuclear payloads over long ranges, according to the nonprofit Missile Defense Advocacy Alliance.

Although North Korea recently committed to “work toward” denuclearization at a historic summit between President Donald Trump and North Korean leader Kim Jong Un, Hill said, “I don’t see the (missile) threat, regardless of what country that you might be referring to, necessarily just stopping.”

Instead, Hill said that threat “continues to grow, no matter what region you are in.”

The Missile Defense Advocacy Alliance said the United States is pursuing hypersonic missiles to deliver conventional payloads, while China and Russia plan to equip hypersonic missiles with conventional as well as nuclear warheads.

Hawaii will always be a militarily strategic site in a strategic location, Hill said, adding that the United States wants to keep pace defensively with the missile advances.

He said that as a result of an analysis of alternatives, “we determined that we needed another radar in this area in order to detect out as far as we can to discriminate as far as we can,” primarily for ballistic missiles.

Discrimination refers to the ability to differentiate warheads from rocket debris and decoys.

“We know that Hawaii is adequately defended today due to the ground-based missile defense program (in Alaska and California),” Hill said, “but with this radar we will be able to take on the advanced threat.”

Hill’s comments came before and after an informational public meeting Tuesday at Sunset Beach Elementary School in Haleiwa as part of an environmental impact statement being conducted by the Missile Defense Agency.

Approximately 160 acres would be used for the radar, which will identify, track and classify long-range ballistic missile threats in the midcourse of flight.

The facility will have communications equipment to transfer data to a fire control system for 44 interceptor missiles that are in Alaska and California and provide ballistic missile defense for Hawaii and the mainland.

Also planned are entry control and maintenance facilities, water supply and treatment buildings, and an electrical substation.

Kuaokala Ridge adjacent to the Air Force’s Kaena Point Satellite Tracking Station, and two sites at the Army’s 9,500-acre Kahuku Training Area, are being examined.

Three public meetings provided an opportunity for residents to talk to experts at different stations without any formal presentation. Tuesday’s attracted a relatively small number of residents.

Lynn Nolan, who lives near Sunset Beach Elementary, said she can see one of the handful of existing antenna domes at Kaena Point from her home.

“It’s going to be something that we’ll all see” if the new radar is placed there, she said. She also said “that’s a very pristine area for hiking,” and wondered about ongoing access.

But Lance Hayashi, who is employed by the Air Force at Kaena Point, said the extensive trail system behind Dillingham Airfield and access to Peacock Flats would not be affected under current plans.

Bob Leinau, a North Shore Neighborhood Board member, said he thinks the visual impacts at Kaena Point would be minimal.

“We have a couple of radars up in Kaena. We’ve got radar on Mount Kaala. We’ve got radar all the way at the end at Kahuku. We’ve got windmills. I don’t think one more thing is going to kill it,” he said.

The Missile Defense Agency’s Hill said the radar may be similar-looking to the Cobra Dane radar in Shemya, Alaska, which also is blocklike in shape, but has a larger, 95-foot radar face. The radar detects objects out to 2,000 miles.

Hill said the visual impact at Kaena would depend on the big radar’s placement on the ridgeline.

“When I look out at the ridge and I imagined what a radar that size would look like when I was driving up here, it will be a speck up there in terms of scale,” he said.

The environmental analysis might take a year to 18 months, an official said. Construction is expected to start in 2021, with initial operating capability late in 2023.