Oahu residents, whether or not they’re persuaded this is the right move for Honolulu, have to acknowledge that Jan. 18, 2011, was a day for the books. The Federal Transit Administration issued a document called the "record of decision," which amounts to the green light to start building the 20-mile elevated rail system ultimately linking Kapolei to urban Honolulu.

That means shovels can actually turn some dirt in March, which is when the city contractors expect to begin relocating utility lines, an essential chore before the first station, the first stretch of tracks, can start taking shape.

After all the decades of false starts, the years of tax collections, the contentious hearings, the islandwide vote, this thing now looks like a reality, though one that’s still viewed from a distance. So much still has to happen that it’s mind-boggling, not the least of which is the creation of a transit authority staffed with professionals who can give the project the informed oversight it needs.

Almost certainly their first priority will be to get the next contracts issued, beginning with building the train storage and maintenance facilities in Waipahu. The promised jobs for Hawaii’s people and economy are eagerly awaited, as is the eventual easing of traffic. All of the steps along the way must be taken with a full measure of public notification; transparency at each stage of the project is of immeasurable importance to maintain public trust in the expenditure of some $5.5 billion on Hawaii’s largest-ever taxpayer-funded project.

But the public has its duty, too. Along with the trains that someday will shuttle riders between Points A and B, the project will trigger the redevelopment of communities surrounding its 21 rail stations. Some of these stops will be located at established destinations that probably won’t change as much — Aloha Stadium, Pearlridge Center or Leeward Community College, for example.

However, some are districts that will be preparing for "transit-oriented development" or TOD, which is planner-speak for the more dense aggregate of retailers, workplaces and residences that grow up around stations. This is viewed as a means to jump-start the construction industry and provide multifamily housing developments more affordable than those in sprawling subdivisions.

But the residents already living there need to buy into this, too. If stops are envisioned well, these live-work-play complexes will become less of a jarring intrusion and more of an integrated addition to established neighborhoods. The community embraces what it’s helped to design, making the improvements vibrant and lasting.

Conversely, the lack of a community buy-in produces the sad, abandoned stops that rail critics often picture as a byproduct of mass transit.

The process is well under way for the East Kapolei and Waipahu stops; the most recent community meetings took place in November to produce the Aiea-Pearl City station (comments on this one are still being taken, through Feb. 28). All the draft plans created so far can be viewed online (www.honoluludpp.org/planning/).

City planners say the San Francisco-based firm Dyett & Bhatia has been hired for the next stops, including Kalihi and Downtown. Preparatory work, such as creating community opinion surveys, is being done, but residents should keep an eye out for announce- ments about public meetings. Chief planner Kathy Sokugawa invites people in those communities to e-mail lhonma@honolulu.gov to get on a mailing list.

The most successful developments are those that are not imposed from above but come together at least somewhat organically, directed in part by the people who will be most affected by it. This must be what Honolulu wants for its rail-centered communities, but it won’t happen unless people step up and help to sketch the outlines of their preferred future.