The City Council’s Committee on Transportation voted unanimously Tuesday to report for adoption a federally mandated rail safety plan that identifies the city’s transit agency as the final responsible party of the rail system, which is still under construction by the Honolulu Authority for Rapid Transportation.

The full Council is expected to review the plan — now called Resolution 38 — for approval and holds its next meeting April 19.

Covering the city Department of Transportation Service’s oversight into the operations and maintenance of the rapid transit system, the rail safety plan states it “serves as a guiding document describing the various safety-related roles and responsibilities, system safety activities, the processes for identifying and managing the potential system hazards, and a means for managing system safety for the operating rail system.”

The plan also outlines the rail line’s three segments: the West segment from East Kapolei to Aloha Stadium, which includes the first nine stations; the Airport segment extending the rail line to Middle Street and adding four stations; and the City Center segment, terminating at Halekauwila Street in Kakaako and adding six stations.

The planned opening of the first segment of the nearly $10 billion, 19-station project is this summer — from East Kapolei to Aloha Stadium — aboard Hitachi- built, four-car, driverless trains. The full build-out of the 18.75-mile rail line is scheduled to be completed by 2031.

Prior to the vote, committee Chair Tyler Dos Santos- Tam questioned the city over the initial hours of operation for rail under city control: 5 a.m. to 7 p.m. Monday to Friday and 8 a.m. to 7 p.m. Saturday, Sunday and holidays.

Dos Santos-Tam also asked whether the city had the ability to amend those hours “if it’s shown there’s a need to do so if there’s overwhelming demand or perhaps underwhelming demand at certain times” on the rail line.

In response, Roger Morton, director of DTS, said the decision on operating hours for train service was determined two or three years ago when the contract with the project’s lead contractor, Hitachi, was negotiated.

“It is an interim operation while we extend the system,” said Morton. “So based on our analysis on bus ridership, in particular, we determined most of our bus ridership drops off precipitously after 7 p.m.”

Morton added that keeping the initial hours for rail service was a “question of balancing the cost of operating the rail system but also all of the associated bus service that accompanies the rail system.” He noted that “parallel bus service” would be part of the interconnected nature of the new rail line.

“So we’re not limiting the ability of people to travel back primarily to the west side and Ewa … but going into the next interim operations we then have service that operates much later than that,” Morton said.

Once rail begins full operations, the hours will be modified to 4 a.m. to midnight, according to DTS.

Calling the rail safety document an “organic plan and a living plan,” Morton said the City Council can always amend the rail’s hours as needed. Under later Council questioning, Morton said the system’s trains will run at shorter intervals in arriving and departing to and from stations, particularly during peak periods of commuter traffic.

“We, on the first segment, will be running our system every 10 minutes,” he said. “It means no matter what time you arrive at a station the longest you’re going to have to wait is 10 minutes.”

As the system expands toward the airport, Morton said, “the later night service will revert to a 15-minute schedule rather than a 10- minute schedule,” and into the final stretch toward downtown, the “peak periods will go down to as close as every 6 minutes.”

Meanwhile, on a separate but related item at the meeting, the city, in conjunction with HART, is embarking on a study to reevaluate the use of a previously planned parking garage for the rail station at Waiawa Pearl Highlands in Central Oahu — an area near Kameha­meha Highway, close to the H-1 and H-2 freeways.

In 2022, construction of that station’s parking garage was halted, in part, due to its cost — estimated at $330 million — and not restarted.

“What we’d like to analyze is the housing and commercial potential that can be merged with this property,” Jon Nouchi, DTS deputy director, told the committee.

“As you know, affordable housing is one of the priorities of this administration and, I know, of the Council, and any time we have the ability to do true transit- oriented development, it would be a great opportunity to co-locate a lot of housing, some very useful commercial activities and other opportunities to connect.”

Nouchi added that other communities might connect more easily to this station, and a new neighborhood might even develop in proximity to the rail line if such a plan proved feasible. He noted that DTS already has hired a consultant to study the matter.

But Council member Val Okimoto — whose Council district covers this area — questioned city staff that besides the cost to build the Pearl Highlands parking garage, the ground beneath it wasn’t stable enough to support its construction.

“How are we going to now build housing or other things?” Okimoto asked. “I want to make use of the structure — I see it on my ride home — but am I understanding that correctly, that the ground wasn’t safe to (build on) and that’s why we couldn’t finish the parking structure?”

In response, Lori Kahi­kina, HART’s executive director and CEO, said the “soft substrate underneath was making the parking structure so expensive.” She added, “I hear what you’re saying, so if you put housing over it, it’s going to make it even heavier. So I think that’s what DTS is saying — that we have a consultant to try and take a look at that.”

Okimoto replied that she was not against the plan per se.

“I just want to make sure that we’re really fiscally prudent and we think things through,” she said.

“What I don’t want is to have another project that’s presented to us and then the neighborhood is told that we can’t complete it again. I don’t know if the community would stomach that.”

In the end, the panel voted unanimously to approve a resolution to see DTS and HART study parking and other transportation options at the Waiawa Pearl Highlands project.