Monday, September 10, 2007

No big-city jams - but now's the time to take on Victoria traffic
Sept. 7, 2007

I noticed in this week’s Times-Colonist that the paper is planning a series on commuting in Greater Victoria. They’ve put out a request for commuter stories, so allow me to be among the first to weigh in.
I’m one of those lucky folks who are able to pick their own start/stop times for work, at least to the extent of avoiding the worst of early-morning and late-afternoon traffic.
So I won’t pretend to know what it feels like to be a frustrated commuter fighting her way through heavy stop-and-go traffic every day. But I do get caught in the crush fairly often anyway, because it’s hard not to if you’re driving anywhere near one of the region’s trouble spots at the wrong time of day.
Civil engineers, physicists and flow experts have been trying for decades to figure out traffic jams, the reasons for which go well beyond the superficial explanation of too many cars crammed onto too few roads. The latest theories view traffic as an element, capable of changing its form under certain conditions.
On a slow time of day on a wide-open road, the theory goes, traffic is comparable to a vapour or gas. Cars travel with ease at whatever speed each driver chooses. With more cars on the road, it manifests as water – still flowing, but at a much more fixed and inflexible rate that makes it harder for drivers to switch lanes or make quick adjustments.
And when the commuter rush is on, traffic turns to ice, leaving you and your car frozen in place.
Sometimes there’s an obvious explanation for the freeze: A stalled car; a poorly planned on-ramp; an accident. But not always. Traffic can slow to a crawl and then speed back up again for no particular reason.
“All of a sudden to go from free flow to stop-and-go – this remains one of the mysteries of our time,” traffic expert Hani Mahmassani of the University of Texas commented to the Washington Post when asked about the phenomenon.
While an overload of cars can’t explain everything, it’s definitely a factor. Traffic simply can’t flow as smoothly on a road originally built to carry 100 cars an hour once development has quadrupled the number of vehicles using the route. The “Colwood crawl” exemplifies that particular problem.
But traffic volume isn’t the whole story, as anyone can attest who has experienced the late-afternoon McKenzie/Trans-Canada Highway jam. Why is it that traffic travels at regular speeds through all sorts of busy intersections around the region – including those on either side of McKenzie - yet frequently slows to a stop at that one?
Sometimes the culprit is bad planning. I suspect the reason that westbound traffic piles up on the Bay Street Bridge at various times of day is because some planner made the big mistake of putting in a single shared lane for vehicles coming off the bridge at the Tyee Road intersection regardless of whether they’re trying to turn left on Tyee or drive straight through.
That shared lane means nobody travelling west across the bridge can move forward until cars turning left on Tyee have negotiated their turn across a fairly steady stream of oncoming traffic. With the lack of an advance left-turn arrow complicating the situation even more, traffic can sometimes back up all the way to Bridge Street and beyond.
In the years when I drove from Gordon Head into the downtown every day, I discovered the hard way never to attempt a left-hand turn across McKenzie in the morning, when a mass of University of Victoria commuters was making its way to school and work.
A morning traffic jam caused by doughnuts and coffee was shaping up in the same neighbourhood just as I was moving out of the area last year, the result of Tim Horton’s devotees trying to turn left off Shelbourne into the restaurant’s drive-through.
Now that I live in Esquimalt, a whole other group of problem roadways has emerged.
A late-afternoon trip from this side of the water to any area remotely close to the West Shore, for instance, is simply not on. Nor do you want to be heading out on Interurban or Wilkinson roads when commuters start flooding back home to Peninsula communities in mid-afternoon. (I don’t know how so many people got jobs that let them head home at 3:30 p.m., but that’s when the crunch starts.)
Then there’s that funny little spot where Blanshard Street morphs into Vernon, at the intersection with Saanich Road. Whatever mysterious forces are at work there, I now know to factor in the delay of getting through that intersection when heading out of town to catch an afternoon ferry.
Even the worst commute in the Capital Region has nothing on the best day in Vancouver or Toronto, mind you. Hard-core commuters from the big city would tease us mercilessly even for considering our little 15-minute holdups as “traffic jams.” But all big problems start small.
Got your own stories to share? I know the TC would love to hear them –

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