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CroMagnon

I guess Philly's system and Boston's system are light rail retroactively. They both have tunneled segments offering (slightly) higher speeds in the downtown core with (slightly) greater station separations.

But both are basically streetcar systems otherwise and pre-date the 1960's era concept of light rail using available railroad ROW. They have no expediency.

J

It's a waste of time to try to define different types of rail transit. Like the above post mentioned, there are too many exceptions or hybrids to have a rule. The Boston green line, for example, has a lengthy underground segment, a very long, completely grade separated segment with speeds up to 55mph and distant stops (D), center median running sections with stops every block (B and C) and street running sections that unload directly onto a travel lane (E).

Streetcar, trolley, tram, light rail....who cares? The original plan was to convert most of it to heavy rail anyway.

Humans have a tendency to try to group things. Race is a classic example, but in the real world, everything is a continuous spectrum. There's no point trying to draw a line because no line exists.

Jarrett at HumanTransit.org

J. All nouns are category terms. Without invoking categories, we can't say anything.

You're right that everything is a continuous spectrum. In fact, I make that point in the post. The point of the category terms is to define the spectrum so that you can then identify different points on it. Without the category terms you don't even have a spectrum.

Andrew

It appears that Toronto's proposed "Transit City" has been postponed indefinitely to provincial government budget deficits. Bad news, very bad news.

Chris Smith

I think you correctly point out that the biggest differences are in how you deploy the system - mixed lane operation vs. dedicated right-of-way, stop spacing, etc.

But I also believe that vehicle size is important. We are running Streetcar in some places in Portland (e.g., NW 23rd Ave) where a MAX light rail vehicle would simply be way out of scale.

And if you use stop spacing as your criterion, MAX in Portland is effectively a streetcar in the Central City (and I would agree with that characterization).

Alon Levy

Even within categories, stop spacing matters. Light rail can be done with wider-than-subway station spacing, for examples in Los Angeles and St. Louis, or it can be done with shorter spacing, but still useful for medium-distance trips, for examples in Calgary and Houston.

Edmund Carlson

"It appears that Toronto's proposed "Transit City" has been postponed indefinitely to provincial government budget deficits. Bad news, very bad news."

Bad news indeed, but not quite as clear cut, or complete as that. Prior to yesterday's announcement we had the Eglinton, Sheppard, Finch and SRT lines funded, with Jane, Don Mills, Waterfront and Scarborough-Malvern scheduled for some indefinite future. This was backed with something over 9 billion in provincial funds, from which the Premier now asks that 4 billion be cut. Realistically, that means that very little money is going to be left after the (already under construction) Sheppard line and unavoidable SRT conversion is complete. Network requirements and the Pan Am Games mean that the SRT extension is probably also safe, so we are still getting a reasonably complete Scarborough network for 2015 (and the announcement doesn't touch the eastern waterfront lines or the Spadina subway extension), but the rest of the network is somewhere between stalled and dead.

It really is starting to feel like any form of enhanced transit for Eglinton is cursed, and quite likely to bring down anything it might be attached to. For my part, though I haven't been the greatest proponent of Transit City, this is the last straw. I now fully intend to leave Canada once I finish my planning degree in 2011 (well, really the GTA and Ontario, but there aren't too many other places to get an entry level transport planning job in Canada these days).

EngineerScotty

Ahh. But what, exactly, is a "stop"?

It's important to remember--not all stops a vehicle makes are for the purpose of picking up or dropping off passengers--but all stops a vehicle makes affect its average speed. Vehicles which have to stop at traffic lights, wait for other vehicles to get out of its path, or wait for pedestrians--are just as stopped as a vehicle at a platform. Dwell time is probably lower--but this is why it's pretty much useless to consider a line "rapid" if it needs to make a significant number of stops other than the planned ones. While increasing the distance between planned stops will improve performance, you soon reach a point of diminishing returns unless you remove obstacles and cross-traffic from the vehicle's path.

It's interesting to compare three distinct downtown Portland train segments: The Blue/Red lines between Goose Hollow and Rose Quarter, the Green/Yellow between Union Station and PSU, and the Streetcar between PSU and NW 23rd. Finally, we also consider the Yellow Line between Rose Quarter and Denver Avenue, which runs in the median on Interstate Avenue north of downtown.

Red/Blue: 18 minutes, 11 stops (including both endpoints), ~2.2 miles. ~7.3MPH, avg stop distance ~1100ft.

Yellow/Green:10 minutes, 6 stops, ~1.3 miles, , ~7.8MPH, avg stop distance ~1370 ft.

Streetcar: 25 minutes, 18 stops (NB), 2.4 miles, ~5.75 MPH, avg stop distance 750 ft.

Yellow: 12 minutes, 7 stops, 4 miles, ~20MPH, avg stop distance 3300 ft.

Ignoring the Interstate line for now. Average stop spacing DOES affect speed for these routes, but not by much-- the Yellow/Green alignment has 33% grater stop spacing than the Red/Blue, but is only 7% faster. These two routes run in exclusive transit lanes (Red/Blue have MAX only, Yellow/Green is shared with busses), and neither has signal priority.

What if we removed five of the stations on the Red/Blue segment, essentially increasing the average stop distance to 2200 feet? Assuming each stop removed saves 45 seconds (dwell time, plus acceleration and decelartion time), gets us down to 14.25 minutes instead of 18--and a resulting average speed of 9.26 MPH, about a 25% improvement. Remove 7 stations, getting stopping distance to ~3300 feet? 12.75 minutes, about 10.4 MPH.

Now when you compare the Red/Blue line to the streetcar, we find that the Red/Blue segment has a 33% greater average stop distance than does the Streetcar, and runs 27% faster. However, the Streetcar runs in mixed traffic, and thus has a lot more to contend with. A frequent issue is that platforms are located at the ends of blocks, right before stoplights, and the Streetcar will find itself stuck at a light behind an auto, and need to wait for the light to turn green so it can advance 10', align itself with the platform, and open the doors--after which time the light is red again.

So why is the Interstate segment nearly 3x as fast as the Red/Blue (and nearly 2x as fast as a hypothetical alignment with similar stop spacing), despite both segments running in reserved lanes (with no phyiscal separation) alongside auto traffic? Signal pre-emption. Downtown, the trains have to wait for stoplights; along Interstate Avenue the cars have to wait for the train. Another factor is less pedestrian traffic to contend with--the train can accelerate to a higher maximum speed than downtown--but even then, it cannot approach anywhere near highway speeds.

FWIW, Metro did an analysis of how fast it would take to get from Rose Quarter to Goose Hollow were a subway with 2 intermediate stops to be built--the time they estimated was six minutes, or an average speed along the stretch of--you guessed it, 22MPH, only a small improvement over the at-grade Yellow. At that stopping distance, grade separation doesn't buy much over surface running with preemption, apparently--OTOH, surface running with preemption probably wouldn't work downtown, so its either build a subway or do what TriMet in fact did.

Bottom line, I think--stop spacing is important, but so is the exclusivity--more accurately, they go hand in hand. It's pointless to run a mixed traffic service that stops infrequently (for passengers), but still has to contend with stoplights (this is one reason express busses typically run on highways--otherwise, they might as well stop and pick up passengers and run as a local). Likewise, it's usually a waste of money to build grade-separated routes which pick up passengers every couple of blocks.

Brent Palmer

"It's pointless to run a mixed traffic service that stops infrequently (for passengers), but still has to contend with stoplights"

Very true. In Brisbane, bus routes 330 & 340 run express for a distance of 6 miles, but constantly get held up at signals anyway. Thankfully a busway is under construction along this very corridor.

David in Ottawa

Reading Yonah's piece it seemed to me he was proposing a third category of 'light' rail: the tramway, a distinction which I've always made. To me a streetcar line and a tramway are not the same thing, which is why I find your ascribing of his "new" definition as curious, well, curious. It just seems obvious, really.

Streetcars, to me, operate like buses in mixed traffic with no signal priority and frequent stop spacing. Streetcars are almost universally single vehicles of relatively short length comparable to a bus or articulated bus. Most of Toronto's streetcar lines are like this, but over time they have become more separate.

Light rail is, well, "light" rail. These are generally separate and exclusive rights of way like railway lines, and have longer stop spacings with signal priority if not pre-emption. The trains are frequently multi-car trains in the higher volume systems, just like a regular train. The corridors look like railways (i.e. visible ties on open ballast) and can often be found in a railway corridor (Calgary & Edmonton being good examples), or, in exceptional cases, they actually use railway lines (such as Ottawa's O-Train). The bus equivalent is the busway, which looks like a highway for buses.

Trams fill the middle ground. They use road rights of way but are exclusive or nearly so (possibly shared with buses and emergency vehicles). They basically use a lane per track and there may be signal priority but not necessarily, though traffic signals may well be optimized for them. Trains on a tram line are typically a single car but sometimes have a second. The tracks are typically embedded in the road surface, though it is often a different surface than the rest of the street. Stop spacing would typically be greater than a streetcar but less than a light rail system. Again, the bus equivalent is exclusive bus lanes. Many of Toronto's streetcar lines are now what I would call tramways.


One tends to find tramways more in Europe, but over time some tramways have come to look more light rail-like, especially further out, while still being called "trams". The classic streetcar operating in mixed traffic seems to be a lot less common in Europe. Similarly, Toronto's system has become more tram-like, but it still calls itself a streetcar system because much of it still is and because that's what it was always called. Toronto's new light rail lines are mainly what I'd call tramways as well, with a few exceptions. And of course the signature light rail system in North America, Calgary, has what is essentially a tramway at its core in downtown Calgary on 7th Ave. Clearly there is evolution along the spectrum with systems "borrowing" up and down the spectrum combined with the retention of historical names. The mixing along the spectrum is found in BRT a lot as well, with cities like Ottawa having everything from mixed traffic running on free-flowing parkways/expressways to exclusive bus lanes right up to fully grade-separated busways.

Beyond light rail is what could be termed "light metro". These are completely grade-separated systems like a metro but employ lighter equipment with light rail-like performance characteristics (radii, grades) that is often (maybe even usually) automated. Vancouver's SkyTrain is a good example.

anonymouse

I think operationally, stop spacing is the best distinction. The only other real distinguishing characteristic between streetcars and light rail (which is basically a modern-day interurban: an electric train that happens to also run on streets) that works even in cases with streetcar-like light rail and light-rail-like streetcars is turn radius. I'd define true streetcars as those systems which, when used in street running, have a turn radius that is small enough to fit within typical existing street ROW. This is one of the key technical differences between Muni's and VTA's systems.

EngineerScotty

Of course, MAX makes corners in downtown Portland--barely, and with much squeaking of wheels. (And then there's the infamous hook turn just west of Sunset TC, where the trains literally do a 180 pulling into the station...and a similar tight curve on the Red Line approaching Gateway TC, when coming from the airport.)

Cap'n Transit

For any set of transportation terms there will be three communities that use them: locals, tourists and transit planners.

Locals will adapt to whatever terms are chosen. You can call the wide-spaced, separated ROW system a "bus" and the short-spaced, mixed-traffic ROW system a "metro," and people will get used to it.

Tourists may have a little difficulty, but they'll figure it out.

Planners and advocates are used to dealing with a range of terminologies: the same thing is called a "Metro" in one city, a "subway" in another and an "underground" in a third. If you really need to be precise, then focus on the characteristics, not the name.

EngineerScotty

Cap'n makes a good point--though I'd object that the word "bus" has a specific meaning; and I suspect that the people would have a difficult time getting used to calling a wide-separated ROW system a "bus" unless in fact it has rubber tires (in which case, they'd have no problem). Calling a bus a train and vice versa doesn't do anyone any good--and I've always found terminology like "trackless trolley" (for BRT systems, generally) to be dumb.

In general, transit authorities ought to not abuse terminology for marketing reasons; if they want to be distinctive or cute, come up with a unique name, rather than abusing established terminology.

Alexander Craghead

A more accurate definition is whether or not vehicles must obey street laws. In short, a streetcar is just that -- a railcar that operates on the "street", meaning not just in the street but *as a street vehicle*. This means they are subject to the same traffic laws as regular automobiles, right down to stop lights and turn signals.

Light rail, by contrast, is a railway. They can operate in the street, sure, but strictly speaking they do not obey traffic laws and they are not controlled by traffic signals. They operate by their own rulebook, operational hierarchies, and control systems. They are no different than conventional railroads that possess street trackage.

Of course this definition of streetcar vs. light rail is too esoteric and insider for a layman to grasp easily. Stop spacing, much like the presence of the track in the street right-of-way, is not particularly relevant to determining mode. At best it serves as an easily identifiable surrogate for a more accurate delineation.

As for tram, that is just another fuzzy term that generally describes any transit that is operating in the street. It's just a European equivalent of "trolley" and is so widely misused that it is just as meaningless as a way of defining a level of service.

cph

The distinctions between "streetcar," "light rail,", etc. are admittedly very fuzzy. Especially so for people not all that familiar with rail transit (e.g. most of the US).

Names also vary across the country and in other parts of the world as well (for example, "tramway" in Europe is more or less what we'd call a "streetcar" in the US. The word "tram" as used in the US brings to mind one of those tractor-pulled monstrosities used to shuttle people around the Disneyland parking lot!

Perhaps we should devise new terms for these services, and start afresh?

Brent Palmer

Alexander Craghead: "Light rail, by contrast, is a railway. They can operate in the street, sure, but strictly speaking they do not obey traffic laws and they are not controlled by traffic signals. They operate by their own rulebook, operational hierarchies, and control systems."

That's OK if the entire light rail system enjoys exclusive ROW. If there are on-street stretches involved (shared or reserved), it's safer for the signalling to be consistent with general traffic signals - albeit with extra signals such as a white or green letter T to signify free passage for the light rail vehicle.

EngineerScotty

Don't knock the Disneyland trams. As short-distance point-to-point people-movers, they work pretty well. They're not particularly comfortable, of course... but they get the job done.

Can you imagine busses used in that application instead? The parallel boarding capability of the trams is quite important.

Jarrett at HumanTransit.org


I should clarify that as far as I'm concerned, "tram" and "streetcar" are synonyms. "Trams" seem to be the European and Australian word for what Americans call streetcars. The term tram may fuzz into light rail in Europe, but in Australia, it's clear that Melbourne's slow, frequent-stop, mixed flow things are trams, i.e. streetcars, while Sydney's more rapid-stop and exclusive lane thing is called light rail. My understanding is that the new line being built on the Gold Coast will be called light rail as well.

Alon Levy

David, what you describe as light rail doesn't really exist outside Canada. American light rail projects are usually what you'd call a tramway, running in street medians in physically separated lanes. Even in Calgary, most LRT lines follow freeways, not freight rail lines. In both the US and Canada, cities typically start with one freight rail corridor for LRT, and then move on to streets and highways once they run out of rail corridors.

Chris

The European city I live in (Manchester) has in the Metrolink a hybrid system similar to that which David in Ottowa describes. It's definitely a light rail in the suburbs (widely spaced stops on a pre-existing rail alignment) and a 'tramway' (largely exclusive ROW with some bus/emergency vehicle sharing and moderately spaced stops) in the city centre/inner city development areas, but has some sections of on-street running where an exclusive ROW is impossible. Confusingly people call it both "the Tram" or "the Metro", when really it's neither.

It's being expanded over the next few years on largely the same model. Two new lines will be former heavy rail alignments and two will be largely exclusive at grade tramways with some on street running. The model does seem to support Jarret's point about the purpose of the system though. In areas where regeneration is the prime motivation for construction the route is less segregated and stops are more frequent, whereas on the lines where commuters are the priority segregation is much stricter and stops much less close. However as a system the distinction between "light rail" and "tram" doesn't make any sense, as it's both.

Alexander

@Cap'n Transit, @Jarret

Regarding the call-it-anything-we'll-follow idea, and also the Australian tram vs lightrail distinction, when the St Kilda and Port Melbourne lines were converted from heavy to light rail, maps of the tram system marked the lines distinctly and clearly called them "light rail". The term was fashionable at the time, I gather.

Still, everyone calls it a tram, and nowadays it's not marked or marketed any differently (except that the tramstops than used to be train stations are marked like train stations in the defacto standard Melway street directory).

So apparently, we won't call it just anything; a part light-rail is still a tram.

Most of the route length is on road, with standard on-road (i.e. short/frequent) stop spacing. But almost all of this --- afaik, all except the top kilometre or so of Nicholson St East Brunswick is separated or at least on dedicated lanes. And just as well, some of those five-segment, 30+ m trams can be a terror to overtake (or be overtaken by).

In another Australian city, maybe they could've been a light rail, but I suppose it wasn't "different enough" and the alternative name just couldn't catch on.

What's the Glenelg tram in Adelaide like? The photos I've seen have had physical separations from the cars, small bumps, but I don't know any more than that...

ws

@EngineerScotty

Do you have access to Metro's subway study? I tried to search for it but no luck. And 6 minutes through downtown is a worthwhile investment, considering it now takes 20+ minutes to get through it. 15 minutes could be the deciding factor of taking an car or taking transit.

My opinion of the blue/red line is to underground it completely through downtown and use the existing rails for an east/west streetcar line with mixed auto traffic and light prioritization.

Downtown is getting quite cluttered with just too many things running on the streets at once. And we have very narrow streets and lots of intersections too.

I might add that the yellow line along Interstate does benefit from slightingly larger block sizes in some parts, which probably helps its times. The small blocks of downtown are really the bane of mobility imo, and the MAX is literally "maxed" out as far as adding more cars to a single line.

We need to spend more and do it right the first time. We keep spreading ourselves thin with "eye-candy" projects like a transit bridge from starchitects and sleek aerial trams; instead of taking a good look at vastly improving a very lauded, overrated, but ultimately mediocre transit system (as far as efficiency wise) to get more people to ride it. I can't argue with some of the numbers and passengers that use our transit system, but it could be so much better with just a bit of attention.

EngineerScotty


Actually, my recollection was in error--the tunnel considered was a tunnel from Goose Hollow to Lloyd Center, with one intermediate station near Pioneer Square--which would reportedly save 12 minutes off MAX for the same trip. Given that the MAX trip from Goose Hollow to Lloyd Center is about 22 minutes, that would imply a 10-minute trip between these two points--which sounds kind of slow for an underground line with an average stop spacing of about 6000 feet.

It's in the Regional High Capacity Transit Plan summary report, on page 45.

Regarding the Aerial Tram--it hauls a million passengers per year, give or take, so it's hardly useless. The cost overruns were an issue, and how much of Portland tax dollars were properly spent on a project that primarily benefitted OHSU, is an interesting question--but it does what it was designed to do.

calwatch

That does seem slow, especially since if you tie in the end of the Westside Tunnel to the downtown tunnel you could probably increase speed on the Westside tunnel (currently trains leaving the Westside tunnel have to decelerate while in the tunnel, probably due to safety concerns). I would add a couple more stops there (10th Avenue and perhaps Rose Quarter/Convention Center for a portal for Yellow Line trains), and you could still do it within the 10 minutes allotted. The report glosses over Portland's high water table (it is near a river, after all), which could be a problem, and also the congestion caused when all trains could through the Steel Bridge, and the operational issues that it causes when an accident blocks the bridge, or the bridge has to open for ships. One way to eliminate the former would be to close the Steel Bridge to auto traffic, but you still have Fleet Week and other events which cause chaos to the schedule. Ultimately, in the 2035 time span, a downtown subway seems essential in my opinion.

ws

@EngineerScotty

I had to take my criticism out on something. The aerial tram is meant to serve a few select people and OHSU, it does not exactly benefit the average citizen -- that was my main point.

I'd argue one stop in downtown would save more time than that, like you say. The distance from Goosehollow to Pioneer CS to Lloyd Center 11th (using the route shown on their study pg. 45) is a distance of 2.15 miles. If it took 12 minutes according to the report, that would mean:


10 minutes (.167) / 2.15 miles = 12.8 mph!

Obviously a transit stop takes time for boarding and off-boarding, but I'd like to see their calculations for that. I'm almost convinced to email them and tell them how far off they are on that study of under grounding the blue/red line.

They further put down the idea of tunneling accessibility because it's not on surface streets. A few steps and an elevator for ADA people is not going to hinder accessibility one bit. There's probably not too many major city in the world w/o an underground transit system in its downtown.

An underground LR tunnel would average at least 30 mph including board / on-board time.

On the downside, it did say it would cost 2.2 billion dollars (2009 dollars). But doesn't the city own a tunnel boring machine from the big dig?

EngineerScotty

I believe the city does own one--but getting your hands on a boring machine isn't the expensive part of tunneling.

I suspect that at this time, crosstown trips via MAX aren't the highest priority for planners. Other than westsiders heading to the airport, the vast majority of trips heading towards downtown either originate or end there. Part of that is the slow slog through downtown makes crosstown trips painful--but a bigger part of it is other than the airport, none of the other destinations along MAX outside of downtown have parking which is inconvenient or expensive. Portland's commute times are actually pretty good, so the big driver of transit use is probably parking inconvenience, not avoidance of traffic. West of the West Hills or east of I-205, your're looking at auto-centric sprawl FTMP.

Given that, I'd rather expand the network outwards further, than build a tunnel at this time.

One of the most interesting "future" corridors in the Metro report, is the proposed Washington Square to CTC line, which would run from CTC (the current endpoint of the Green), through Milwaukie, meeting with the "Orange", ending at Washington Square, which would involve a crossing somewhere with the Barbur Line (which many assume will be LRT even though no choice has been made). If it gets to Washington Square, I have a hard time believing it won't be extended three miles further north to Beaverton TC. That line might be useful--there are quite a few people who live in Clackamas County and work in Washington County--and it would run in a corridor that is currently not served well by roads.

ws

I think your view on tunneling the rail lines in downtown is a bit off, and it would benefit more than just pass through trips. It still would increase capacity greatly and decrease times by a decent 7-8 minutes to the center of downtown from either west or east (and just about 15 minute reduction through all of downtown, I'd guess).

That's a huge time reduction, too.

I think one has to ask themselves what so many people are doing on highway 26 through the Vista Ridge Tunnel? Many of them are going to other places than just downtown, presumably to many residential units on the east/west side (and their work place may be in Wash Co.).

You also have the Blazers, Expo Center, Convention Center, Lloyd Center, Airport... not to mention many trendy neighborhoods.

Washington Square is simply an overrated employment center. It's just retail with low wage jobs. It gets way too much priority from planners and city officials with pie in the sky aspirations, imo (Why not look to Nimbus Ave instead?).

Hillsboro, at least, has its Silicon Forest where many crosstown people actually work and generally around where most of Washington County is going to grow with more UGB expansion slated.

ws

I'll amend my statement that Wash. Square isn't a bad place to look for transit options, I just think it's an overrated employment place...but planners missed an opportunity for expanding LR to Wash SQ. from downtown to give SW Beaverton people good transit access.

Instead it was WES instead. Opportunity missed, and any future rail development in this area will be looked at with high skepticism.

EngineerScotty


Low-wage workers ride transit every bit as much (if not more so) than the higher-paid ones--the mall may not be a great place to get a job (I've worked retail before, so I know...) but large malls like Washington Square are good anchors for transit lines. The peak load hours for retail operations (both for workers and shoppers) are generally different than for office workers.

Appealing to higher-wage workers might be useful for building up a better constituency for transit among the electorate (services used by the middle class are far safer politically than those only used by the poor), but in terms of getting butts in seats, a poor butt counts just as much as a wealthy one.

Regarding Nimbus--WES stops there. A very small percentage of the almost-nobody which uses WES, uses that stop. But the office parks along Nimbus are not very transit-friendly--most of the land is taken up by greenspace and parking lots. Were the place to densify--not likely anytime soon, given the present glut of office space in Portland--then maybe.

Another problem with the area is pedestrian access. There aren't any nice crossings of the 217 freeway (only sidewalks along Hall or Scholls Ferry, both of which are very busy urban boulevards. Even though the aforementioned WES stop is only 1/2 mile from Washington Square, you'd be nuts to use WES to try and get to the mall.

As to whether or not WES has "blown it" for better transit opportunities that corridor--Metro seems to think that improving the Beaverton/Wilsonville corridor is a high priority. Metro seems to think this would done by making WES frequent service and all day--but I have no idea how they would a) pay for it, and b) get WPRR to agree (the freight railroad which either owns the rails or is primary tenant thereon, still likes to run freight trains when WES is not in service).

Ericorozco

When I begin my first explorations of a city, I like to categorize its corridors. A "streetcar" street is distinguished immediately to me by a small-grain commercial corridor immediately abutting neighborhoods on either side. The corridor is an "active edge" between distinct residential subareas. These streets, while they may be heavily traveled thoroughfares, serve in a non-arterial capacity and have direct access to a well-connected street fabric. Interestingly, sometimes I discover that these active edge routes where at one point in their history actual streetcar routes.

Rapid transit corridors, on the other hand, are functionally best when they connect active nodes (that can be existing neighborhood centers or planned TOD's) but when they travel primarily along inert edges between these nodes.

That Toronto paradigm is very useful. Central Toronto has beautiful examples of streetcar corridors. I envy how long these active edges are and how perfectly the abutting dense single-family neighborhoods serve them, in their extent and vitality. I consider downtown Toronto to be the ideal paradigm for a streetcar-served urban fabric.

In short, I think of two kinds of urbanisms with regards to streetcar and light rail service. The former is Richard Sennett's liminal edge and the latter is a concentric strategy, creating "transect" centers. These urbanisms can blend and interact with one another, so yes, both modes can serve the blended topography of a city adequately. It's just that streetcar should be associated with the former, the LRT with a centripetal strategy to concentrate activities in centers.

Really, the best urban design strategy would find a way to balance/reinforce these two urbanistic conditions that urban areas love to create almost without guidance. You have to ask the city first what it has been creating already and what it wants to create first ...then you choose your mode. The patronistic strategy to first chose the mode and make the city bend to it is probably going to resist all your good intentions.

Yuri

Perhaps a simpler definition is that any at-grade rail that operates at less than an average of 15 mph over its route length is not light rail because it can't be considered rapid transit. A bus in Los Angeles without a dedicated lane operates at about 10 mph, so for me that's a definite lower bound. Without an exclusive ROW and wider stop spacing, it would be difficult for an at-grade rail to achieve 15 mph in an urban setting.

Capacity is another distinction. Even if they were to use the same rolling stock, the streetcars I've seen operate as 1-car trains. Maybe there are 2-car streetcars somwhere. But I doubt there are 3-car or 4-car streetcars in operation.

Alon Levy

Ericorozco: roads that carry subway lines are usually anything but inert. Yonge in Toronto and Broadway in New York are both examples of main streets with ample commercial development on top of busy subways. In fact most streets with subways in New York are important edges; back during the el era, the streets underneath the els were again important edges.

Ben

Wanted to add that Toronto's Transit City's stop spacing is going to be 400-500 meters apart (0.25 to 0.33 miles). "Rapid transit" according to this blog's definition is at least 800 meters (0.5 miles).

To help illustrate how this plays out, the Sheppard LRT will run west-east through an area where north-south arterial roads are about 1 mile apart, with a secondary collector road in between. Considering the suburban nature of this route, it would make the most sense to have it stop at every arterial road at least, and every arterial and collector road at most. Instead, it is going to stop at an arterial, then in between, then collector, then in between, then arterial...

Ericorozco

@Alon I realize that subway lines can indeed constitute a special hybrid. I have in mind primarily the surface options of less dense cities in my neck of the woods, where rail transit of any kind is still young and hardly understood (esp. insofar as the particularities and virtues the two types were discussing here are concerned).

I know that in the South especially this can be a confusing matter for planners, because both streetcars and LRT lines will cross through segments where they are interchangeable. Our centers and corridors in the South are just too dispersed and ad hoc. Planners kind of want a bit of both, and don't understand the trade-offs.

In Charlotte, for example, there are long sections of the streetcar route that will have to function as what we call "Light Rail Lite" until the arrival of LRT on an adjacent (and inert edge) arterial, which will be simultaneously converted to an expressway. The streetcar corridor is already an "active edge" in spite of its heavy volume of vehicular traffic (in fact, many of our most diverse and vital districts are along it). But right now, we have to keep moving commuting traffic on it as a priority. We have to build up first the capacity of the surrounding transit/commuting network before we begin to put more frequency on the streetcar route (although we are exploring options using express bus service on the streetcar corridor as an interim solution). It's an interesting balancing act.

Mikeymichelle

Stuttgart has been upgrading their "trams" to "light rail" for the past 20 years, and is almost finished. I got a tour of their facilities last fall, and I asked them what THEY considered the differences to be. In German, they call their new system U-Bahn; U stands for the German word for Independent (i.e. ROW)(although in other German cities U-Bahns are the metro and U stands for underground. ) Other upgrades were wider radii for faster turns, and undergrounding downtown so it really looks and functions like metro in the inner city.
Clearly there is a fuzzy line between the two
and even some parts of their new system are still tram-like, in mixed traffic.
I wrote about the differences on my blog here:

http://cittastadt.wordpress.com/2009/10/11/more-about-ssb/

Nathanael

"That's OK if the entire light rail system enjoys exclusive ROW. If there are on-street stretches involved (shared or reserved), it's safer for the signalling to be consistent with general traffic signals - albeit with extra signals such as a white or green letter T to signify free passage for the light rail vehicle."

It may or may not be safer, but it's not done often.

Light rail systems generally have their own signals and do *not* follow the same traffic laws. Example: HBLR, RiverLine, and Newark City Subway in NJ.

I think Alexander Craghead is in fact correct about the actual technical difference between "light rail" and "streetcars". Does it follow the same rules as a car or does it not?

Mikeymichelle

sorry that was the wrong blog entry- here is the pertinent stuff: The features of the UBahn in Stuttgart:
* Each line is numbered and has a distinct color and are shown on all city maps.
* Level platform boarding.
* Underground in the center city with multiple platforms for the intersecting lines.
* Service frequency: every 10 minutes or less
* Service hours: 4:30 am to 1:30 am.
* Distinctive signing, real time information.

Upgrading from Tram to Light Rail -what exactly did they do in Stuttgart?

* Switched from 1.0 meter gauge to standard gauge.
* Increased min horizontal curvature radius from 25 m to 50 m.
* 8% max grade to 8.5% max grade.
* 100 % priority at traffic signals.
* Independent ROW, (except a few exceptions at the extremities of some lines).
* Computer controlled with automatic breaking if operator failure.
* Electronic display destination signs inside the vehicles.

Other upgrades from the former tram cars:

* Air-conditioning
* Wide panoramic tinted windows
* Outside arm rests
* Coordinated interior design
* Upholstered seats
* Spacious entry ways
* Space for bikes, wheelchairs and prams
* Intercom communication with driver
* Regenerative braking

j Albert

The delay to Toronto's Transit City gives a better chance to make the right decision. Unlike (as highlighted in another recent article on this very informative website) in cases such as Vancouver, citizens here in Toronto never enjoyed the ability to comment in alternatives.

It's a accurate characterization that Transit City is being sold as 'rapid transit' - whereas the expected stop spacing is closer to streetcar type spacing than it to that of light rail. Some proponents admit that the scheme is supposed to drive redevelopment rather that solving mobility problems.

The plan has - in my opinion - three major problems:

1. It does not address the main problem the inner-suburbananites need addressed in terms of mobility - that is to shorteni the time it takes to reach downtown.

2. It is supposed to spur development by making the wide arterials more 'attractive'. However, I can find no case where running rail tracks down the median has magically made for pedestrian-friendly environment. I feel that the proponents somehow think that running the rail will magically transform these roads into downtown like streets. Is there any example of this happening in other cities? I have asked, but have been provided with no examples.

3. The TTC plan is to encase the rails in concrete. This means that the lines will need to be rebuilt every 25 years or so. Toronto is pretty extreme in terms of freeze-thaw cycles.

The Spadina LRT line began service in 1997 - and is scheduled to be rebuilt in 2012 - after only 15 years! In the downtown network, the TTC can make up for lost capacity on one route through diversions. Even with this, life and traffic can be chaotic for months while relatively short sections of track are drilled out with large jackhammers.

When the first Transit City line needs to be rebuilt, there are will be no alternatives - and the lines will take much longer to rebuild. Life on Sheppard East will be disrupted by the building for years - but the construction nightmare will come back every quarter century. This a hardly going to make the streets attractive for densification.

Steven Dale

In terms of Toronto's Transit City, station spaces will be around 400 m apart, not all that much greater than streetcars.

Red frog

In Europe LRT is seldom used. Even the cities themselves, like Strasbourg (the city that showed to the world, back in the mi-1990s, that a tramway could be a thing of beauty) Paris, Lyon, Montpellier, Bordeaux, Reims (featured on this blog last summer), Croydon, Manchester etc. etc. call their rail transit vehicles on rail a TRAMWAY (the French have always used that term. There is no French word.) or Tram for short.
http://en.wikipedia.org/wiki/File:TramStrasbourg_lineA_HommeFer_versIllkirch.JPG

http://www.trams-in-france.net/reload.htm?bordeaux.htm
(check various trams on the column at left)

According to the Light Rail transit Association (www.lrta.org)
What's the difference between tramways and light rail?
Mike Taplin, the LRTA's Chairman answers: First, when we say tramway we mean streetcar in the American way of using words. For instance, there is a streetcar line in Seattle running from the Waterfront to the train depot. In Portland they have a light rail line running from the city centre to the eastside (and now a new line to the westside). These lines are light rail because they are mostly segregated from other traffic, passengers get on and off at stations rather than in the street, and the cars run faster. However there is no definite border line between streetcar and light rail - they merge gradually from one to another, and as a streetcar system gets upgraded it becomes light rail. A lot of this is to do with planning jargon; streetcars are seen to be old fashioned whereas light rail is trendy!
The terms Rail and Trains are seldom used in Europe for trams. As for the size, Siemens Avenio trams go from 18 metres long (2 articulated sections) to 72 metres long (9 sections), carrying from 105 to 510 passengers depending on the length and width).

Alstom trams most popular model is the Citadis 402 tram. It is 44 metres long, in 7 articulated sections and carry around 300 people.
As a comparison the Max type 4 cars (3 sections) are 29 metres long/ 95 ft. They usually run as a set of 2 cars.

Red frog

The lrta quote stopped just before in Europe rail ....I had trouble posting quickly enough..

Adam Fitch

What is the point of all this bickering? Obviously, any transit operator with a brain will stop more frequently in denser areas and less frequently in less dense areas, because of the densities of users and destinations.

If exclusinve rights-of-way are available, transit companies will use them, of course, because it just makes their lives, and those of their riders, easier. And exclusive rights-of-way are just more available and cheeper in the less dense areas.

A taxi is car whether it stops once a day or a thousand times a day. It does not turn from a streetcar to a light road vehicle and back again, just so that transit-fans will be able to categorize it. The customers know that it is a taxi no matter how it operates.

Now, the real reason behind all of this debate is the politics of transit planning. Give the public and politicians some credit for being able to understand the more subtle distinctions.

When new systems are being plannned, discussed and debated, call them streetcar/LRT systems, and give a few simple diagrams. Just be honest.

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