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  #81  
Old Posted Jan 30, 2022, 4:40 PM
Crawford Crawford is online now
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Originally Posted by IrvineNative View Post
That's the point. A high capacity heavy rail system should have better frequencies (without interlining) then a light rail system.
No, a heavy capacity train usually has lower frequencies, because there's more capacity. This is especially true for commuter rail, and most of BART is functionally commuter rail. Light rail isn't commuter rail.

When a light rail line replaces a bus line, the frequency usually drops, because the light rail service usually has higher capacity.

And commuter rail service, around the planet, has lower frequencies than bus and light rail. Even A+ systems like the Paris RER have much lower frequencies than major Paris bus/light rail routes. This makes sense because you're comparing a train moving 2,000 people to a bus/light rail moving 50-100 people.
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  #82  
Old Posted Jan 31, 2022, 4:12 PM
jmecklenborg jmecklenborg is offline
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If you take a train from Penn Station to Babylon, or a train from Grand Central to North White Plains, you'll never have a crossing. In fact for most of the main lines, you're never at grade. You're on an elevated structure, an embankment or a trench.

In the postwar decades, they converted the busiest lines to rapid transit-level infrastructure.
I don't think I've ridden a LIRR train in about 10 years, and my experience is limited to riding to/from the Islip airport from Ronkonkoma. There definitely were a few grade crossings on that line when I first rode it in the late 90s, as well as platforms that were shorter than the trains.

An extremely obscure fact is that the route and service pattern of Cincinnati Rapid Transit Loop was changed five years into construction. It was originally planned to be a true double-track loop and to have zero grade crossings, but after the buying power of the 1916 bond issue was halved by WWI inflation, in a scramble to buy property to create a line that could function, the board was forced to buy private property that would have necessitated a handful of grade crossings in this area: https://www.google.com/maps/search/o.../data=!3m1!1e3

I have the property line maps of the purchase somewhere at my house. The loop operating pattern was abandoned (at least temporarily) so that the thing would operate as a traditional line, with a station at Madison Rd. serving as the origin and terminal station of all trips, and all trains would share about 2,000 feet of track before either traveling on the western side of the loop or the eastern.
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  #83  
Old Posted Feb 16, 2022, 1:25 AM
IrvineNative IrvineNative is offline
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Originally Posted by Crawford View Post
No, a heavy capacity train usually has lower frequencies, because there's more capacity. This is especially true for commuter rail, and most of BART is functionally commuter rail. Light rail isn't commuter rail.

When a light rail line replaces a bus line, the frequency usually drops, because the light rail service usually has higher capacity.

And commuter rail service, around the planet, has lower frequencies than bus and light rail. Even A+ systems like the Paris RER have much lower frequencies than major Paris bus/light rail routes. This makes sense because you're comparing a train moving 2,000 people to a bus/light rail moving 50-100 people.
The Toronto Subway has higher capacity trains than most US LRT systems. Yet the Toronto Subway has trains every 2-3 min. during peak hours vs 15 minutes for US LRT.

I agree that it's natural for commuter rail to have bigger trains and lower frequency than LRT. But subways/urban metros have bigger trains than LRT AND have higher frequencies.

The BART is a urban metro. A metro-commuter rail hybrid, I'll give you that, but still more of an urban metro, and still needs higher frequencies compared to the San Diego Trolley (especially since Downtown SF is far bigger and denser than Downtown SD).

Even compared with another US subway-commuter rail hybrid (the DC Metro) the BART has inferior frequencies, because it has only one transbay tube. The DC Metro at least has two, rather than one, crossing over the Potomac, as well as a line (the red line) that is not interlined at all with any other line, whereas all BART's lines interline with another line for at least part of their length.
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  #84  
Old Posted Feb 16, 2022, 1:06 PM
nito nito is offline
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The biggest barrier to frequencies is the quality and type of signalling, grade separation, rolling stock acceleration and deceleration, and platform availability for turning services around. It is why you can have non-metro railways that can and do operate at higher frequencies than bus routes and light rail lines.

Many countries have been deploying the European Train Control System (ECTS) to provide automated or automated aspects on non-metro railway lines, particularly where there could be a mixture of services (e.g. rural and intercity). Such upgrades can deliver higher frequencies and faster operating speeds, at the same time as increasing safety.
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  #85  
Old Posted Feb 16, 2022, 4:25 PM
mhays mhays is online now
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Light rail can be reasonably frequent. Seattle will have three-minute frequencies in its core grade-separated section when a second line opens (pre-Covid plan at least), and six-minute frequencies for the tails.
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  #86  
Old Posted Feb 16, 2022, 4:34 PM
Crawford Crawford is online now
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Originally Posted by IrvineNative View Post
The Toronto Subway has higher capacity trains than most US LRT systems. Yet the Toronto Subway has trains every 2-3 min. during peak hours vs 15 minutes for US LRT.
I don't understand your point. We're talking generalities, not extremes. And we're talking about the U.S.

In general, lower capacity transit has higher frequency. Yes, the Tokyo Metro has higher frequency than the Omaha bus. Irrelevant.

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Originally Posted by IrvineNative View Post
The BART is a urban metro.
No, it's functionally commuter rail. MUNI is the urban light metro serving SF.

Quote:
Originally Posted by IrvineNative View Post
Even compared with another US subway-commuter rail hybrid (the DC Metro) the BART has inferior frequencies, because it has only one transbay tube.
No, BART has inferior frequencies because it's lower ridership commuter rail. There's nothing preventing BART from running more trains, as only one portion crosses the bay. BART is overwhelmingly an East Bay, Oakland-centered service.
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  #87  
Old Posted Feb 17, 2022, 7:24 PM
IrvineNative IrvineNative is offline
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Originally Posted by mhays View Post
Light rail can be reasonably frequent. Seattle will have three-minute frequencies in its core grade-separated section when a second line opens (pre-Covid plan at least), and six-minute frequencies for the tails.
Precisely. Let's not forget that Link Line 1 is similar to BART in that it is long (will go from Everett to Tacoma) and is designed as a semi-commuter service, kind of like BART.

If Link Line 1 has 6 minute headways at the tails, there is no excuse for BART branches to have 15 min headways.
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  #88  
Old Posted Feb 17, 2022, 7:46 PM
mhays mhays is online now
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But BART does have four lines on a single track, so the core section in SF proper gets frequent service. It also has longer trains than Link.

Link, btw, was utterly jam packed on some peak runs pre-Covid, to the extent that people would sometimes have to wait for the next one since we lack Tokyo-style pushers. I worry about capacity in the spoke immediately south of Downtown. The only difference will be they're now 400' (four car) trains instead of 300'.
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  #89  
Old Posted Feb 17, 2022, 9:56 PM
jmecklenborg jmecklenborg is offline
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Originally Posted by IrvineNative View Post
Precisely. Let's not forget that Link Line 1 is similar to BART in that it is long (will go from Everett to Tacoma) and is designed as a semi-commuter service, kind of like BART.
You will not be able to do a one-seat ride from Everett to Tacoma. There will be a transfer at or near Federal Way, south of SeaTac.
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  #90  
Old Posted Feb 17, 2022, 9:59 PM
jmecklenborg jmecklenborg is offline
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Originally Posted by Crawford View Post
. There's nothing preventing BART from running more trains, as only one portion crosses the bay. BART is overwhelmingly an East Bay, Oakland-centered service.
What percentage of BART rides originate and stay in the East Bay?
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  #91  
Old Posted Feb 17, 2022, 10:12 PM
mhays mhays is online now
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You will not be able to do a one-seat ride from Everett to Tacoma. There will be a transfer at or near Federal Way, south of SeaTac.
No, there will be a transfer in Downtown Seattle.

The current 1 Line will run from Tacoma to Everett based on current extensions at each end (Federal Way 2024, Lynnwood 2024) and planned extensions (Tacoma Dome 2032, Everett 2037-41).

However when they build the new line from Ballard (2037-39) to West Seattle (2032), they'll create an X with the existing line, so the Everett line goes to West Seattle and the Tacoma line to Ballard.

Tacoma has a streetcar that's also called Link and is also being expanded.

https://www.soundtransit.org/system-expansion
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  #92  
Old Posted Feb 18, 2022, 1:02 AM
IrvineNative IrvineNative is offline
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Originally Posted by mhays View Post
But BART does have four lines on a single track, so the core section in SF proper gets frequent service. It also has longer trains than Link.

Link, btw, was utterly jam packed on some peak runs pre-Covid, to the extent that people would sometimes have to wait for the next one since we lack Tokyo-style pushers. I worry about capacity in the spoke immediately south of Downtown. The only difference will be they're now 400' (four car) trains instead of 300'.

Hopefully the additional frequency from interlining line 2 with line 1 will solve overcrowding.
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  #93  
Old Posted Feb 18, 2022, 1:40 AM
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Originally Posted by Crawford View Post
No, it's functionally commuter rail. MUNI is the urban light metro serving SF.


No, BART has inferior frequencies because it's lower ridership commuter rail. There's nothing preventing BART from running more trains, as only one portion crosses the bay. BART is overwhelmingly an East Bay, Oakland-centered service.
You're wrong, as has been explained to you multiple times.

BART is a hybrid system that acts more like a traditional metro in the core of the system (SF/Oakland/Berkeley, where lines converge, there are more stations, and frequencies are good), and a commuter system out in the suburbs (just one or two stops per town, mostly for ferrying people to downtown SF, and to a lesser extent downtown Oakland or elsewhere). SF is the biggest downtown that is served by the system, by far (almost like it's the primary downtown of the entire Bay Area), and the SF section of track has the highest density of stations, and serves the most densely populated parts of the Bay Area (or any city outside of NYC). Meaning, there are a massive amount of passengers to serve that are going to and from SF. To say that BART is "overwhelmingly an East Bay, Oakland-centered service" is silly as hell.
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  #94  
Old Posted Feb 18, 2022, 6:17 PM
edale edale is offline
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Originally Posted by tech12 View Post
You're wrong, as has been explained to you multiple times.

BART is a hybrid system that acts more like a traditional metro in the core of the system (SF/Oakland/Berkeley, where lines converge, there are more stations, and frequencies are good), and a commuter system out in the suburbs (just one or two stops per town, mostly for ferrying people to downtown SF, and to a lesser extent downtown Oakland or elsewhere). SF is the biggest downtown that is served by the system, by far (almost like it's the primary downtown of the entire Bay Area), and the SF section of track has the highest density of stations, and serves the most densely populated parts of the Bay Area (or any city outside of NYC). Meaning, there are a massive amount of passengers to serve that are going to and from SF. To say that BART is "overwhelmingly an East Bay, Oakland-centered service" is silly as hell.
BART serves a pretty limited section of SF, though. How many people are taking it for intra-SF trips? I have to imagine not that many, as it really just serves a single corridor. In that sense, it doesn't really function as the Metro system for the City itself. Though when you add together Muni + BART + Caltrain, SF has a pretty robust transit system.
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  #95  
Old Posted Feb 18, 2022, 6:23 PM
Crawford Crawford is online now
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You're wrong, as has been explained to you multiple times.
Wrong again.

BART is a primarily suburban, Oakland-centered system. The vast majority of stations, route miles, infrastructure and ridership originates from the East Bay. It's headquartered in Oakland. BART has only one line with a few stations serving SF. There's nothing preventing BART from running more trains. The capacity exists. But it doesn't, bc it's a functionally commuter rail system, not an urban rail system. There is no need to run trains every 2 minutes between Hayward and Fremont. The ridership is overwhelming peak travel and home-work oriented, like almost all commuter rail lines.

In contrast, MUNI is an urban system, centered on downtown SF, serving high frequencies, and with heavy off-peak service, and not necessarily for work commutes. It's usage mirrors that of other urban transit systems.

Big difference in system functionality.
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  #96  
Old Posted Feb 18, 2022, 6:49 PM
jmecklenborg jmecklenborg is offline
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Originally Posted by mhays View Post
No, there will be a transfer in Downtown Seattle.
Interesting. That transfer (probably at Federal Way) definitely was part of the plan at some point, but I haven't done any reading on Seattle's expansion plans in several years. The line numbering must also be relatively new since I don't remember that.
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  #97  
Old Posted Feb 18, 2022, 9:04 PM
mhays mhays is online now
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You're mixing up projects. There was never a transfer in Federal Way. It's just where the 1 Line will temporarily terminate.
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