Those wanting to ride Honolulu’s planned train from East Kapolei to Ala Moana had better go first.

The city’s blueprints call for one unisex public restroom with one toilet at each of the 21 stations. And the restrooms at all but one station will be locked with access available only by contacting a station attendant. A Middle Street Transit Center will have multiple unlocked restrooms.

Limited or no public access to restrooms is not unusual for many mainland commuter rail systems.

Restroom access will be limited because of security and maintenance concerns, said Toru Hamayasu, the city’s chief transportation planner.

"Several systems such as BART in San Francisco and MARTA in Atlanta decided to delete the restroom," he said in an e-mail to the Star-Advertiser. "Old railroad systems such as New York and New Jersey have open restrooms, but they recommend against them for Honolulu.

"Keep in mind that our restrooms are open to public with a sensible security measure."

As planned, an end-to-end ride from East Kapolei to Ala Moana will take 42 minutes. However, about 60 percent of train riders will reach the train via a city bus, which means their total journey could be much longer.

The city hopes its planned $5.5 billion rail line will attract 116,300 riders daily by 2030. Many stations are projected to have peak-hour traffic in excess of 6,000 people — or 100 people per minute.

Questions about the availability of station restrooms were raised during the Environmental Impact Statement process by the Department of Hawaiian Home Lands and the League of Women Voters.

Honolulu resident Amy Kimura wrote that seniors and children need restrooms.

"Any mother with a young child knows that when they say they need to go, you’d better find a restroom quickly in the station, or they’ll relieve themselves on the platform or against a wall in the station," she wrote in comments submitted early last year. "When this happens on the bus, you get off at the next stop and find a bush or the gutter if no suitable place can be found in time."

A need for bathrooms is heightened by the elevated, isolated nature of the planned stations, said Pearl Johnson, chairwoman of the planning and transportation committee of the League of Women Voters of Honolulu. The group supports building a street-level train.

"If there are going to be thousands of people per hour using the station, will one restroom be enough?" Johnson asked. "How will people be accommodated when the station attendant is using the restroom?"

Ultimately, it is hoped that businesses and other transit-oriented developments will spring up around train stations, providing restrooms and other facilities riders will need, said City Council Chairman Todd Apo.

Restroom conditions in public facilities such as parks show how difficult it is to secure and maintain open restrooms, Apo said.

"If we have limited access for situations where someone really needs it, I think that’s sufficient, and I think that’s more than what many other transit systems provide," he said.

According to the American Restroom Association, commuter trains in Atlanta, Boston, Los Angeles and Washington, D.C., have locked public restrooms that are available via a station manager. New York, Baltimore and Miami have public restrooms at all or key stations, according to the trade group.

In many cases a bathroom stall is provided to comply with federal Occupational Safety & Health Administration rules, which require employers to provide toilets for employees such as station attendants. There is no requirement for public transit systems to provide toilets for customers.

"The current plan is to have an attendant at each station, and there will be an operating procedure for the attendant’s access to the restroom, e.g., the attendant has to be relieved of his post by a roving supervisor before using the restroom," Hamayasu wrote. "The OSHA requirements will be met."