- Apr 28, 2020
- Reaction score
Another fascinating post, kudos again to you for the dedication you've shown to the topic, Riverside. I'm entirely in agreement you, both in terms of preferred destination and, more importantly, in the need to consider the network impacts as much as (or even more than) just the ridership potential at the chosen node-station.In this post, I make the case in favor of the Kenmore alignment, largely from the perspective of overall network design. I think this discussion reveals a number of interesting esoteric points about the way the MBTA network functions, and is why I see this as more than just a question of “Kenmore ridership” vs “Kendall ridership” (though I absolutely think that there needs to be a formal study, and I will certainly change my opinions based on the results of such studies).
Kenmore was once actively intended as a transfer node, hence the existence of the turnback loop (which I like to think of as the nameless, less-squeaky western counterpart of my namesake at Government Center); as I understand it the plan at one point was for the C (this predating the Highland Branch's conversion to the D-branch) to loop at Kenmore while the B's tracks would be eaten by the HRT-ified Central Subway. (Ironically, or perhaps poetically, given the clearances in the Tremont Street Subway, it might well have ended up using Blue Line-size HRT stock.) So there's a very good historical argument that Kenmore was supposed to be a LRT/HRT (light/heavy metro) transfer node and that the system's simply been suffering from its never having been built all these years, and that Blue (albeit now via Riverbank) would fix the problem that was intended to have been fixed last century.
I look forward to these future posts. That said, while I'm intrigued by the three-tier concept, I do have a few thoughts. One's sort-of a nitpick, which is that I wouldn't call things like MUNI Metro's streetcars, New Orleans' streetcars (much as I like them), or even the surface-running portion of the E-branch as proper light rail, regardless of equipment. I wonder if there's room for either stratifying the classification between the systems operating in significantly mixed-modes (like with street running, which is really not that far off from BRT) and those that aren't. The Green Line's an interesting example, because a fair number of its problems come from mixing pure grade-separated LRT (D and the Central Subway), two and a half surface branches running in reservations, and half of a branch street running (resulting in the nasty garbage-in, garbage-out difficulty of scheduling the thing to work in the de facto HRT role the Central Subway has been pressed into). (MUNI Metro has some of the same characteristics with its subway, right down to being the other poor fools to suffer the lemons that were the Boeing LRVs.)The other Big Idea I introduce here (which will be the topic of further posts at a later date) is a three-tier distinction between “light metro”, “heavy metro”, and “regional metro”. I think the terms “light rail” and “heavy rail” remain useful in certain ways, but also can confuse more than clarify. MUNI Metro streetcars are famously slow (~8 mph on average), operate in mixed traffic, and have numerous stops that are literally just straight up in the middle of the street; LA Metro’s E Line (formerly Expo Line) operates in a dedicated ROW at near 20 mph on average, with full length high platforms for level boarding. These services should not be placed in the same category.
The other point is that as useful as tiered classifications are for discussions like this in forums like this (even if reasonable people can quibble about the specific definitions), part of me really, really hopes that your tiers don't catch on widely, because I feel like they're ripe for misunderstanding and misuse by moronic politicians who'd happily pick up the "light metro" definition to plaster over the fact that they're building BRT when they should be building LRT. (I can just see the MBTA of the era using "light metro" for the Silver Line just to try and add a bit more lipstick to that particular pig.) Hopefully that's just me being unnecessarily cynical, though
Both of these are excellent points. I think BRT tends to raise a lot of ire around here because of our politicians' nasty habit of trying to use it to solve all problems (and not even doing it correctly when they have). You correctly identify that it's a tool in the transit arsenal, and it should absolutely be used when it is the best fit (like the southern half of the Urban Ring, per F-Line's exhaustive analysis of the excruciating difficulty of attempting to shiv LRT in there).Likewise, if we all get our Indigo wishes, and see EMUs running 7.5 min headways on the Fairmount Line, that is basically mid-frequency heavy rail in almost everything but name. Moreover, heresy though it may be to say, the reality is that certain corridors – particularly circumferential service and radial service outside of an urban core – can be as well-served by true, high-quality BRT as by LRT (and in some cases, even better), with virtually indistinguishable rider experiences between the two.
Here's where I'd push back a little, referencing what I mentioned above. I don't know that I'd necessarily agree that the Green Line from Kenmore-east is as easily classifiable outside of the heavy metro network as it is west of Kenmore. It's certainly being relied upon to do the work of a heavy metro spine, the stop spacing is not that much more dense than the Orange Line, and on a whole it operates far more like a heavy metro than it does BRT; even one of the most significant differences, the vehicles, will be altered by the Type 10s. (Though, as above, that may well all be able to be chalked up to the Green Line being a unicorn hybrid; that it is such a unicorn is, in my view, a very good reason for some of the pressure to be taken off by BLX to Kenmore.)The terms “light metro,” “heavy metro”, and “regional metro” are meant to give us more precise terms to describe the capabilities and roles of different services, deemphasizing a rapidly antiquating distinction between “light rail” and “heavy rail”.
Once we start viewing the T as three overlaid networks (plus a fourth layer of local feeder networks – i.e. most buses), the gap at Kenmore becomes obvious and we can start to plan a more balanced and efficient system for the decades ahead.