One of the advantages of driving a bus for a living, says Dee Wake- night, is that your supervisor isn’t constantly looking over your shoulder.

But the open road is not entirely free; someone had to plot the lanes and pour the concrete. And the road and its rules are the subject of controversy between the Metro and the Amalgamated Transit Union Local 587, which represents Wakenight and 1,400 other drivers of Metro and Sound Transit buses.

More particularly, what’s controversial is Metro’s solution to the engineering and design challenge that arose when it decided to put Sound Transit and Metro buses on the same route through the downtown transit tunnel. The county transit agency will reopen the passage Sept. 24, sending 18 bus lines that have been running on downtown surface streets back underground. They’ll be running through the first synchronized bus-rail tunnel in the nation. In 22 years of driving for Metro, says Wakenight, the bus/train station setup is the worst mistake she’s seen Metro make.

“In my opinion as a professional operator, it’s doomed,” she says.

The problems can be summed up by a measurement: 14 inches, the height from the light rail tracks embedded in the road to each station’s platform. That height makes for a nearly even transition between the floor of the trains (which don’t arrive until 2009) and the station platform.

But Metro’s diesel-electric hybrid buses ride lower than the trains. So, to make bus floors approximately the same height as the platform, Metro poured a four-inch-high concrete bank sloping up the road bed to the curb. As they approach their stops, bus drivers must negotiate this bank, steering their right wheels up it sidelong and onto a lip. Their 60-foot coaches need to come within six inches of the curb.

“It requires a lot more precision maneuvering than driving on the surface streets,” says driver Joshua Laff. “You have to be close enough but not too close.” Too close, he says, and the driver can’t deploy the wheelchair ramp; too far away, and passengers must negotiate a giant step to board or disembark.

The 14-inch platform height also means that the buses’ right-hand mirrors sit at a height of about five and half feet — extending over the passenger area — within striking distance of any unsuspecting commuter.

Metro has outfitted the right-side mirrrors of each of its hybrid diesel-electric coaches with a strobe light that will come on automatically as coaches approach the stations. The agency has laid yellow “tactile strip” in the floor near the edge of the platform; audible warnings, readerboard messages, signs, and security guards will also be on duty. And drivers will obey a new 10 m.p.h. speed limit at the stations. Metro General Manager Kevin Desmond says the likelihood of a commuter being struck by a bus is very slight.

“You’d have to be standing immediately on the edge of the platform and be oblivious to the bus arriving to be hit,” he says. “I’m not saying it would never happen, but I do think the safety measures in place and the professionalism of our drivers will prevent it from happening.”

And Metro’s measures haven’t allayed all drivers’ fears. In this fall’s route-picking rounds, some drivers opted for schedules that didn’t require tunnel driving, says Wakenight: “They don’t want to be the ones to get in an accident over something over which they have no control.”

Amalgamated Transit president Lance Norton sent Desmond a letter Aug. 9 outlining the ATU’s concerns. Metro hasn’t met all of his requests for changes. But it’s a difficult time for the union to push the envelope on tunnel safety, since it’s in the midst of renegotiating the drivers’ two-year labor contract, which expires Oct. 31. Union members and officials alike were loathe to be interviewed, saying they feared negotiations would sour if the union appeared to be publicly casting management in a negative light. Norton, citing the negotiations, declined to speak on the record.

Wakenight says the union is unlikely to refuse to return its operators to the tunnel. But she worries about what will happen to the driver who is dismissed over an accident that happens in the tunnel. People don’t acknowledge what it takes to do this job, she says: good judgment, alertness, tolerance, and extreme punctuality. Get dismissed, and “you’re unemployed, and nearly unemployable, because people think, ‘You can’t drive a bus? What kind of dummy are you?’”