Standing at the corner of Burrard and Pacific, 5 pm on Monday, watching the traffic flows. Something seems familiar.
The traffic is moving. Cars do back up on red lights, but most of the backlog dissipates on the green. Even the worst bottleneck, where cars line up on Pacific west of Burrard, seems to be working itself out. Enough merging vehicles get though the free right between onflows from other directions. The whole intersection functions rather like clockwork.
The way the signals are cutting up the traffic into platoons, merging them together into a southbound flow, like packets on the Internet – it’s like something I’ve seen before.
And then I remember where.
At Denman and Georgia, the same thing. Traffic westbound on Georgia and Pender Streets is cut up into platoons by the upstream signals and then merged with flows from Denman Street to be fed onto the Causeway. The eastbound flow from the Causeway is cut up into platoons before being fed onto the grid by the signal at Denman and Georgia (pictured above).
Outside of rush-hours, it’s like clockwork. And when demand overwhelms the intersections, vehicles are lined up in orderly rows, waiting to be processed.
Vancouver uses intersection signals as meters on arterials that lead into the core, rather like a switching yard, to regulate the traffic flows on and off the downtown peninsula – at Georgia and Denman, Terminal and Main, and now at Burrard and Pacific.
They work better in some ways than freeways which disgorge an uncontrolled flow of traffic onto surface streets. But these switching points have explicitly limited capacity. And Motordom doesn’t allow for limits on the number of vehicles a city is expected to accommodate.
Hence the sense that these intersections are congestion problems, to be solved with more capacity (or at least not reduced capacity), rather than necessary regulators of a system that seems to work rather well once its limits are recognized. Like clockwork.