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Archive for May 18th, 2007

HOT lanes have the best chance of being adopted

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Don Cayo, Vancouver Sun

Published: Friday, May 18, 2007

If the new [Translink] board is both smart and gutsy, it will go for a region-wide “road-pricing” — comprehensive tolls that rise and fall with traffic volumes and have proven effective in places like Singapore, London and Stockholm as a way to ease congestion on major arteries.

But the new Board will not be either. “Smart” only in business matters, it will take them some time to get to grips with the politics of transport. “Gutsy” definitely not because it will have been picked by the province (well, Kevin Falcon actually) to be more co-operative than the existing board. After all, that is why the Mayors are being moved out of the Boardroom into some nominal advisory capacity, since they showed a dangerous tendency to be thoughtful and responsive to the real needs of their constituents. Not all the time of course, but enough to get up Kevin’s nose. And road pricing is currently contrary to provincial road toll policy (though that could be easily changed, especially if they take Gordo’s commitment to CO2 reductions seriously).

And what if the new board has some guts and some brains, but not too much of either one? (After all, that’s perhaps the best we can expect from a provincially appointed body that seems to have come into being mainly because its predecessor rocked too many of Victoria’s little boats.)

Well, then it might be time to consider HOT lanes — in effect, HOV lanes you can buy your way onto with variable, electronically assessed tolls. These are, in my view, a second-rate solution.

Agreed. I was at the same meeting as Don. He asked questions, I am afraid I sat in mostly mute disbelief – though I confess I did laugh once when no-one else did (I saw the metaphorical rabbit being rapidly stuffed back into the top hat). And I did call out one much needed correction.

Munnich isn’t really a technical guy — his specialty is the politics involved in getting something like this off the ground

Which meant that he badly misled his audience over an important technical issue: how many cars were actually moved in the HOT lane? He did that by confusing “capacity” and “throughput” – two important technical terms with very different meanings. Mind you he also confused London and Stockholm more than once, so I am sure it was not deliberate. Though since one of his main claims for the success of his mission was “no question left behind” he really dodged the bullet on greenhouse gas (ghg) emissions.

The question being asked, by Eric Doherty of the Livable Region Coalition and author of “Cooking the Books, Cooking the Planet” , was about the amount of ghg emitted before and after the HOT lane was put in. Munnich went for the Falcon line about less idling. BUT – and it is a big but – he did not realize the significance of a graph he had shown earlier. That had shown that the general purpose lanes had been so badly congested that their throughput had been reduced to around 1,000 vehicles per hour (vph) – or about half their theoretical capacity. This happens because the speed-flow curve (or volume delay function if you prefer) folds back on itself. If you try to push too many vehicles into a lane, it slows down so much that you reduce the number getting through. (You can see this effect first hand on any road crossing the Canada Line construction.) The HOV lane was, of course well below its capacity and thus free flowing. After the HOT lane was put in, all three lanes became free flowing. So the number of vehicles getting through this section of freeway increased from something much less than 3,000 vph to much closer to 6,000 vph. So the ghg calculation is almost certainly worse afterwards, since there are now double the vehicles than there were before.

“the revenues they [HOT lanes] raise can fund improvements in transit, an urgent priority in U.S. cities — and in ours — if significant numbers of people are ever to be enticed to rely less on cars. “

Well, yes, in theory I suppose they could. But in Minnesota they didn’t. They could not even cover their operating cost let alone the capital cost – and a lot of what was needed was already installed since the HOV lanes were fairly recent. And Munnich did not specify either in dollar terms, but it took quite a bit of federal grant money to get HOT installed.

He also pointed out that HOV lanes do not work as well in Minnesota as they do in California. And that is because, as he also noted, you need a whole suite of TDM measures to make HOV work. One 6 mile length of lane is not enough if there is plentiful, cheap parking at the end. Cut down the number of parking spaces, and charge SOVs more for them than car pools, and the sums begin to add up.

There is a video of the presentation

Written by Stephen Rees

May 18, 2007 at 10:50 am