Some progressive US cities are building out new streetcar networks complete with streetcars running in mixed traffic saying that it is good for business and helps to calm traffic, in addition to simply being the preferred option for local public transit.
I don't think it's a stretch to imagine Toronto reversing course on their current streetcar strategy in future years (maybe decades). Bathurst wouldn't be my first pick because the parts of the street that don't already have streetcars are already pretty residential, and the kind of residential that lends itself more to car drivers - large, expensive, single-occapancy, etc., until you get up north of Eglinton.
I can suggest a few places that would be better:
- Dufferin (extremely busy bus line, no room for a ROW)
- The eastern end of Kingston Rd. (that entire part of town is poorly served by transit, plus Kingston has lots of commercial that would benefit from transit riders and traffic calming)
- Rogers Rd. (used to have a streetcar line, and still has a pretty vibrant neighbourhood feeling on the streets)
- The Queensway (theoretically the Queensway could support and ROW)
Of course there should also be a streetcar running all the way to Ontario Place and connecting to Queen at Roncesvalles, and also a Queen's Quay East streetcar.
On the majority of Toronto's streets, mixed-traffic streetcars will be inevitably messed up by traffic congestion. I don't think it makes sense to build such lines just to earn the "progressive" sticker, if they do not result in actual improvement of the service quality.
Those US cities may be in a different situation. Perhaps those cities are mid-size, 300 to 700 thousand of people, and do not suffer from congestion as much as Toronto; then, mixed-traffic streetcars can work well. Perhaps their streetcars replace bus routes with a very low frequency. If a bus running every 30 min is replaced with a streetcar every 10 or every 5 min, of course it is good for business. But the primary cause will be better frequency rather than the change of vehicle type.
The effect may be much smaller on streets that already have frequent bus service. Toronto has 3 areas that are close to streetcar lines, far from subways, and are seeing / have recently seen massive growth: Spadina, Waterfront, West Toronto. Of those, Spadina and Waterfront are served by streetcars in a R.O.W. West Toronto may be in part growing due to streetcars, but notably while King and Queen have mixed-traffic streetcars, Liberty Street does not have any. On the other hand, Dundas and College have streetcars but do not see any particular growth; same goes for the whole streetcar network east of Yonge.
Notably, outer parts of Toronto have good 200 km of wide streets that can host a R.O.W. light rail line plus 4 lanes of traffic. The cost of building per km is similar for R.O.W. light rail and for mixed-traffic streetcar, but the benefit of the R.O.W. light rail is much greater. Therefore, the resources should be spent on R.O.W. light rail first.
Route by route:
- Dufferin is very congested, mixed-traffic streetcars there will be as unreliable as on Queen. Additional problem is the hills south of Eglinton.
- Kingston Road already has plans for LRT north of Eglinton, and for BRT between Danforth Rd and Eglinton. Both of them probably make sense and none of them is going to be in mixed-traffic.
- I am not familiar with Rogers Rd. Maybe streetcars can work there, being a branch of St Clair.
- Queensway streetcar (whether mixed-traffic or in R.O.W.) will have same problem as Lakeshore West: poor connection to downtown via a congested mixed-traffic section of Queen or King. If the WW West LRT connection is built, it will change the game; potentially could serve both Lakeshore and Queensway branches.
- Queen's Quay East, if built, will be in a R.O.W. And yes, this one makes a lot of sense and can be built for a modest amount of money.