Traffic Lab is a Seattle Times project that digs into the region’s transportation issues to explore the policies and politics that determine how we get around and how billions of dollars in public money are spent.

Following a few steps behind other big-city agencies, Sound Transit’s governing board on Thursday kicked off a project to build fare gates within four years.

Members voted unanimously to budget $6 million for design contracts and public outreach, while allowing CEO Dow Constantine to proceed with the estimated $87 million retrofit at 14 of the 39 stations.

Sound Transit light rail operates under a modified honor system, with open station entrances, occasional spot checks by fare ambassadors and minimal enforcement. A third of riders don’t pay, according to recent staff reports.

Fare gates will rake in an estimated $32 million or so in additional income per year, which is enough to pay off the installation cost in three years, then generate money for light rail operations, a consulting report says.

The 14 sites are nine stations from Northgate to International District/Chinatown in Seattle, plus Lynnwood City Center, SeaTac/Airport, Federal Way Downtown, Bellevue Downtown and Downtown Redmond. That group includes the busiest stops, plus the three terminus stops in the 58-mile system. About 85% of passengers would begin or end their trips (and therefore pay) at one of these 14 places.

A June report by WSP Engineers suggests dropping Downtown Redmond, where gates would never break even, and gating Stadium Station to reap fares from sports fans, an idea Sound Transit staff rejects.

“Stadium Station would require extensive construction, including the addition of canopies and special event management to make fare gates work,” spokesperson Rachelle Cunningham said. Its surface-level entrance is considered risky because people who dodge fares, or are part of a swollen postgame crowd, could wind up on the tracks.

That’s a main reason light rail here launched in 2009 without gates: Three street-level stops in Rainier Valley and two in Sodo were considered unsuitable because people would walk along rails to avoid gates. Sound Transit, in its infancy during the early 2000s, emulated many design features from Portland Tri-Met’s mainly surface routes, including nongated stations.

Since then, the mostly elevated Vancouver, B.C., SkyTrain replaced its open station entrances with fare gates. This decade, Bay Area Rapid Transit and Washington, D.C., Metro replaced their old fare gates with new types that are too high to jump, while New York City has started retrofitting, too. Los Angeles Metro has fare gates in all subway stations and nonsurface light rail stops. BART reports significantly less vandalism and crime.

Sound Transit anticipates ordering gates at least 5 feet high, and people would have to tap an ORCA fare card or ticket to both enter all stations and to exit the gated stations.

There was little drama in Thursday’s discussion. The contentious part comes later when contracts are signed, especially if neighborhood or social-justice activists raise objections about making stations harder to use.

Whether politicians overseeing Sound Transit will persevere on fare gates remains unknown. Thursday’s staff report calls for process “off ramps” where the board can suspend its 14-station pilot project.

Officials have worried about practical challenges, such as getting youth to obtain and carry ORCA cards (even though they ride free) so they can escape the gated areas. Efforts are underway to get more discounted fare cards, to pay $1 fare instead of the standard $3, into the hands of low-income people before gates arrive. Service staff are still needed to help confused or reluctant people leaving trains, and perhaps guide them to a ticket machine. Some wide gates are needed at each entrance for people in wheelchairs.

King County Executive Girmay Zahilay, a transit board member, wondered about “unintended consequences” that cause barriers for vulnerable people who rely on transit. “What have you been able to find about impacts on youth, impacts on unhoused people, impacts on undocumented or unbanked people, is there any data that’s reliable about that?” he asked.

Because gates in Vancouver and L.A. were installed many years ago, “we don’t have good data,” answered Brian de Place, director of security and fare engagement. Sound Transit will study these sorts of equity questions, then measure after gates begin, he said.

Board member Teresa Mosqueda, a Metropolitan King County Council member from West Seattle, wondered about accessibility for people with disabilities and how to encourage bikes. Other cities have provided wide gates, replied Margaret Cederoth, planning and policy director. “There’s also a way of calibrating the gates, so that when it closes, … it will actually allow you to move through comfortably,” she said.

Fares were projected to cover only 2.6% of this year’s $3.3 billion Sound Transit budget, mainly covered by local taxes and the federal government. Fares provide about 12% of the cost to operate the trains, below the 40% goal the agency originally set in the 1990s, and nearly reached in the late 2010s.

Bottom line, fare gates can defray operating costs somewhat, and maybe lower the blood pressure of frustrated taxpayers, if more riders pay their fair share. Gates aren’t lucrative enough to fund new trains to Ballard and Issaquah.