Towards the end of a long post about the Canada Line yesterday, Stephen Rees makes a point that’s very challenging for those of us who want to see Translink build more subway or elevated light metro in addition to surface-level light rail.  Here’s the short version of his point.

First, we need to get very clear about what our goals are.  If you take all the individual trips that people in the Lower Mainland make in a day, some percentage of those trips are on public transit, and some other, larger percentage are in cars.  Above all else, we want to increase the percentage of trips people make on transit, and decrease the percentage of trips they make in cars.  In transit geek jargon, we want to increase the mode share of transit, and and decrease the mode share of cars.

Rees’ criticism of subway and elevated trains is that they don’t always make any headway towards this goal.  Those trains often replace surface-level public transit.  But when they do that, they free up extra space on the road, which inevitably gets filled up with more cars.  So while the grade-separated trains might attract more riders than whatever buses they’re replacing, the newly less-congested roads also attract new drivers.  Then the mode share can stay exactly where it was before you went to the trouble of building a metro.

In contrast, suppose you built some surface-level rail or set-up a serious bus rapid transit system.  Then you’re get new rapid transit infrastructure to attract and carry new riders.  But at the same time, you’re not making any new space for cars.  In fact, maybe you’re taking some road space away from cars with dedicated transit-only lanes.  Some drivers stop using the now more-congested road, and you successfully increase transit’s mode share on the route.

I take this to be a very serious objection to the idea of building more light metro in the Lower Mainland.  I’m honestly not sure what I think about it just yet, so I’m going to think out loud about a possible response.

Two points.  First, keeping rapid transit on the road isn’t the only way to reduce space on the road for drivers.  Second, increasing congestion isn’t the only way to give drivers strong incentives to get out of their cars.  I’ll take these points in turn.

There are a lot of ways of transforming road space into space that promotes more walkable, bikable, and livable communities.  Real bike lanes–ones that are separated enough from car traffic to make even casual cyclists feel safe–should take up entire lanes of a lot of road.  The first hints of data from the Burrard St. bridge bike lane experiment suggest that might be just what’s needed to encourage more people to start biking.  I wish Vancouver would seriously consider something like Copenhagen’s recently announced system of bike “superhighways.”  But besides bikes, I’ve argued that the city should give up road space for pedestrians.  We should permanently build out sidewalks into what’s now the curb lane of traffic in high-density commercial strips, so restaurants and produce stands can move out into the sidewalk.

But reducing road space isn’t the only way to give drivers incentives to get out of their cars.  Translink is considering a variety of policy levers that would make it more expensive to drive a car.  The proposed vehicle levy should probably be a good deal more expensive than $200 on luxury cars and gas guzzlers.  Roads ought to have tolls.  Parking ought to be a lot more expensive downtown.  And maybe the biggest thing of all, the gas tax ought to be a lot more expensive.  Once driving gets expensive enough, people are going to do it less.

So why not build more grade-separated rail lines, give the extra road space to cyclists and pedestrians, and make driving a lot more expensive? You might think that all else equal, it’s just better to tax people less and look for cheaper ways to invest in public infrastructure.  But since I’m not afraid of a little redistribution, I don’t think that.

The most compelling reason I’ve been able to think of so far is crassly political.  It’d be a lot easier to reduce road space by talking about the cost-saving advantages of light rail, than to raise taxes on drivers and then give road space space to cyclists.  (Can you imagine the Province‘s editorial board reacting to a plan to raise taxes on drivers and then to give their precious, God-given road space to hooligans-on-wheels?  The mind reels.)

This post has gone on too long.  In any case, I’ve been thinking of Rees’ points for a day now, and I’d be extremely interested to hear him elaborate on them.