Back to the topic of Los Angeles, I think the real question for any success in the Los Angeles region will be if/how/when the cities and counties of the region decide to intensify development in the areas around the stations that are being built. It would cost a pretty penny but I think the division between "LRT" and "HRT" in LA is less meaningful because there's a lot of grade-separated LRT that functions much like the GL/GLX here in the Boston region and the key thing holding back the LRT network is core capacity restrictions in the Downtown area because of overlapping routes downtown. I think with LA Metros program of infrastructure toward 2028 though, they're going to be leaps and bounds ahead of us and SF in ridership from sheer number of destinations covered.
Yes. L.A. user LRV's for fleet commonality, but the way it's deployed runs the gamut from "traditional" mixed-running to "HRT by any other name". HRT itself has no distinct definition apart from LRT other than the smell-test. Things like third-rail vs. overhead happen with either, low-vs.-high boarding happens with either, large vs. small multiple-unit running happens with either. I guess you could say that HRT requires sealed-corridor grade separation on all service patterns since virtually 0% of the systems that namecheck themselves as modern/non-grandfathered HRT have any permissible track access...but LRT can quite literally dupe the same properties. After all, the prevailing D-to-GLX Riverside-Medford Hillside run-thru pattern that debuts with GLX--save for the ped crossings at D platforms--is 98% sealed all the same.
MetroRail C Line, as noted, is 100% grade separated, all- prepayment stations, and non-interlining with the mixed-corridor routes...and can run pretty long lash-ups at peak, and has very long (often island-setup) platforms to accommodate lots of future train length growth. That's a smell's-test coin flip from calling it HRT...as you would hardly be able to tell it apart from our Blue Line if you sampled a random selection of its stations as an out-of-towner. MetroRail's LRV's are also
high-floor,
level-boarding even at street-level stops...which is an against-the-grain purchasing choice for most LRT systems and serves to further blur the lines between mode identities when the same equipment is run on these new sealed corridors. In L.A. the mixed-running stops outside of grade separation simply have shorter platforms for typically trolley-like 2-car trains...whereas on the C you really, really can't tell the difference between HRT because the platforms are all pre-built for 4-6 car lash-ups banking future growth.
L.A. does have two more conventionally-built HRT third-rail lines--the B and D--which are interconnected. Those two look hardly any different from our Red Line. Their choice of rolling stock seems to weight more to what 2D lines they build on a map could/will be interlined at some point rather than "grade separation = copy New York"...but they have that luxury for scale because of their (not rare by any means...but somewhat uncommon) choice of level-boarding LRV's lets the grade-sep lines morph into HRT lookalikes simply via adding cars to the train. So in reality they have two born HRT lines, a 'trans'-identity LRT line that's fluid on what pronouns you call it, another 'trans'-identity line about to go live, and a few born mixed-running LRT lines. Where their growth is basically set up to weight the scale more in the HRT direction on a few trunks...whether they outright change the type of rolling stock or just keep it as-is but in longer lash-ups.
For their purposes it was the ideal choice for giving them every conceivable option while leaving no future prospects sold short. Any other city on the planet would organize its transit under different assumptions, so they're not necessarily "better" for it. The fact that high-floor trolleys are kind of harder to pull off in heterogeneous running environments means that definitely wouldn't be a rational choice for Boston, and probably 70% of other LRT-planning cities would opt for low-floor because that's where the biggest flex is in it for them. So there would be naturally sharper distinctions in most places between LRT and HRT than in L.A. where they could put up with high-platform ramps at street level because there really isn't a high total (or desired total) of street-level stations on their system and more of their growth is going to be in grade-separated stations (if not
always on sealed-separation corridors). Stuff like the Urban Ring attached to Green Line, for instance...that's definitely going to be low-platform infrastructure given where most of those stops are situated. That's "best" for us, whereas hybridized high-floor was clearly "best" for them.
