KINGMAN - If you've ever walked up and down Stockton Hill Road on a busy afternoon, you might wonder whether it's worth pushing the pedestrian crossing buttons to get through the numerous intersections along the way. After all, earlier this year, ABC News did an expose on a phenomenon known as "Placebo Buttons," pedestrian crossing buttons that have been disabled in metropolitan areas due to improvements in detection technology or a need to allow large numbers of vehicles to move at a constant rate, without frequent interruptions by pedestrians.
According to that report, as many as 80 percent of the pedestrian crossing buttons in New York City have been disabled and are there simply for show, while the buttons in Sydney, Australia, are disabled during most of the day on weekdays. And while it's true that here in Kingman it might often seem like the buttons do nothing, Public Works Director Rob Owen says they do, just not as swiftly as some might want them to.
"They all function. We test them twice a year and we're in those cabinets pretty regularly doing maintenance, and they all do what they're supposed to do," Owen said. "But you have multiple phases at each signal, so (the timing) is not going to be identical every phase - like if there's left turn movement, you can't allow pedestrian crossing."
According to city electrician Rick Pierce, each of the city's traffic signals has anywhere from two to eight "phases," each governing which lights are on at which part of the intersection, and each lasting a different length of time. For example, the intersection at Stockton Hill Road and Kino Avenue has four phases - one for each cardinal direction. Each phase has a set minimum green light length - in this case, 26 seconds going north and south and six seconds going east and west - as well as shorter lengths for yellow and "all red" - that second or two between when one light
turns red and the next turns green. Each intersection also has set lengths of time for pedestrian signals, including the "walk" and "pedestrian clear" signs - usually represented by a white walking figure and a flashing orange hand. In the case of Stockton Hill and Kino, the "walk" times are seven seconds for each direction, but the "clear" times vary, depending on which street pedestrians are trying to cross. For Stockton Hill Road, it's 10 seconds, while for Kino, it's 18.
But just because someone hits the pedestrian crossing button doesn't mean they'll get a walk signal right away, since the traffic signal has to get through its minimum green time first. The process is further complicated at intersections such as Stockton Hill and Detroit Avenue, where left-hand turn signals introduce four additional phases to the overall timing cycle.
Additionally, many intersections are equipped with loop detectors, metal grids buried in the roadway that can detect whenever a vehicle has pulled up to the light. Like the pedestrian crossing buttons, loop detectors serve as a way of telling the intersection to deviate from its regular operations to accommodate the new circumstances.
"All this stuff is interacting at the intersections, you got the loop detectors and the buttons," Owen said. "You've got all these different variables interacting, which could account for some discrepancy in the timing. On Beale Street downtown, the times are going to be shorter for pedestrians to cross Fourth Street than it would be for Andy Devine Avenue or Eighth Street. They're all pretty much individualized depending on a lot of those variables."
Stockton Hill Road is somewhat of an exception, however, since it undergoes a process called "coordination" at several high-volume periods of the day. During coordination, signal lengths change in order to maximize the flow of traffic north- and southbound.
"If you got on Stockton Hill Road at Detroit and moved at 30 miles per hour, you'd get a green light all the way to Gordon," Pierce said. The problem is, of course, that not everybody moves at 30 mph, especially along the business corridor, where traffic frequently turns onto the roadway.
During coordination, pedestrian signals also change their regular schedules. For example, you could stand at the corner of Stockton Hill and Detroit for ten minutes waiting to get a walk signal to cross Stockton Hill, and it would never come up unless you hit the pedestrian call button. By comparison, if you were trying to cross Detroit, it wouldn't matter whether you press the button once, ten times, or not at all, since the signal will always come up at regular intervals.
"It's gonna signal anyway, and using the button won't get you anywhere any faster," Pierce said.
Of course, despite the city's best efforts, the coordination program still leaves much to be desired along Stockton Hill Road, especially during Kingman's peak driving hours of 11 a.m. to 1 p.m. That's why Owen is hopeful that citizens will take the chance to speak out on a transportation improvement plan for the city currently being worked on by the Arizona Department of Transportation's Justin Feek and engineer Bryon Patterson.
The transportation plan coordinators held one public input meeting at the City Council chambers July 12, but the meeting was only sparsely attended. ADOT is hoping more people will come out for the second meeting, to be held in the Council Chambers from 5:30 to 7:30 p.m. Nov. 8. Additionally, public comments and suggestions for the plan are still being accepted through the project's website, www.azdot.gov/mpd/systems_planning/kingman.asp, and by directly contacting Feek at (602) 712-6196 or via e-mail at email@example.com.