4 ms·

What's wrong with at-grade rail, presuming signal priority and dedicated lanes? Works fine in Geneva, Amsterdam, etc.

by chris_7 10y ago

jdavis703 10y ago
Works fine until someone driving by runs over the passengers who are de-boarding [0]. Or until someone crashes into the train [1]. [0] http://sf.streetsblog.org/2016/02/18/muni-taraval-meeting-met-with-grimaces-groans-and-grumbles/ http://sf.streetsblog.org/2016/02/18/muni-taraval-meeting-me... [1] http://www.sfgate.com/bayarea/article/Car-crashes-into-Muni-train-in-West-Portal-6036557.php http://www.sfgate.com/bayarea/article/Car-crashes-into-Muni-...
- slyall 10y ago
  Sounds like a poor design, most places will have people boarding from sidewalks or a raise area. As for the 2nd, people run into stuff in the cars all the time. Around 50-100 people die each day on US roads. And in the story you mentioned only the people in the car were injured, nobody on the train.
- chris_7 10y ago
  This is solved by bollards.
CydeWeys 10y ago
It's not really comparable to heavy rail in terms of speed or capacity. You can fit 1,500 people into a single NYC subway train, way more than any light rail system in existence, and the express trains go way faster than any light rail because they don't have to worry about potentially hitting stray pedestrians, bikers, or vehicles. NYC subway cars will go up to 55 mph going express or in tunnels. At-grade light rail simply can't go that fast, or even if it could, it wouldn't do it because it's unsafe.
- chris_7 10y ago
  Yes, but at-grade light rail isn't an alternative to subways, it's an alternative to buses. The M23 et.al. barely hit ten mph.
  - CydeWeys 10y ago
    Select-bus service (that is, buses running in dedicated lanes) is about as fast as at-grade light rail, and significantly cheaper to construct. NYC has been going in that direction for awhile. Building at-grade rail is just a complete non-starter. The city already tore out all of its above-ground rail a long time ago for a variety of reasons that persist to the present day.
mattst88 10y ago
In Portland, a far too frequent cause of MAX (the light rail) service interruptions is due to car/train collisions. See the following links for a small taste: http://koin.com/2014/04/01/1-hurt-car-max-crash-portland/ http://koin.com/2014/04/01/1-hurt-car-max-crash-portland/ http://www.oregonlive.com/portland/index.ssf/2013/06/max_collision_with_car_in_down.html http://www.oregonlive.com/portland/index.ssf/2013/06/max_col... http://www.oregonlive.com/portland/index.ssf/2015/05/max_blue_and_red_lines_delayed.html http://www.oregonlive.com/portland/index.ssf/2015/05/max_blu... https://www.reddit.com/r/Portland/comments/3d5i9g/saw_an_orange_line_maxcar_collision_on_my_bicycle/ https://www.reddit.com/r/Portland/comments/3d5i9g/saw_an_ora... There may be more to it in Portland than "at grade", but that certainly seems to be a large component of the problem.
- chris_7 10y ago
  From the photos, it looks like bollards would have solved most of these? It's not really a dedicated lane if drivers can just wander into it.

What's wrong with at-grade rail, presuming signal priority and dedicated lanes? Works fine in Geneva, Amsterdam, etc.

by chris_7 10y ago

What's wrong with at-grade rail, presuming signal priority and dedicated lanes? Works fine in Geneva, Amsterdam, etc.

Works fine until someone driving by runs over the passengers who are de-boarding [0]. Or until someone crashes into the train [1]. [0] http://sf.streetsblog.org/2016/02/18/muni-taraval-meeting-met-with-grimaces-groans-and-grumbles/ http://sf.streetsblog.org/2016/02/18/muni-taraval-meeting-me... [1] http://www.sfgate.com/bayarea/article/Car-crashes-into-Muni-train-in-West-Portal-6036557.php http://www.sfgate.com/bayarea/article/Car-crashes-into-Muni-...

slyall 10y ago
Sounds like a poor design, most places will have people boarding from sidewalks or a raise area. As for the 2nd, people run into stuff in the cars all the time. Around 50-100 people die each day on US roads. And in the story you mentioned only the people in the car were injured, nobody on the train.
chris_7 10y ago
This is solved by bollards.

CydeWeys 10y ago

It's not really comparable to heavy rail in terms of speed or capacity. You can fit 1,500 people into a single NYC subway train, way more than any light rail system in existence, and the express trains go way faster than any light rail because they don't have to worry about potentially hitting stray pedestrians, bikers, or vehicles. NYC subway cars will go up to 55 mph going express or in tunnels. At-grade light rail simply can't go that fast, or even if it could, it wouldn't do it because it's unsafe.

chris_7 10y ago
Yes, but at-grade light rail isn't an alternative to subways, it's an alternative to buses. The M23 et.al. barely hit ten mph.
- CydeWeys 10y ago
  Select-bus service (that is, buses running in dedicated lanes) is about as fast as at-grade light rail, and significantly cheaper to construct. NYC has been going in that direction for awhile. Building at-grade rail is just a complete non-starter. The city already tore out all of its above-ground rail a long time ago for a variety of reasons that persist to the present day.

mattst88 10y ago

In Portland, a far too frequent cause of MAX (the light rail) service interruptions is due to car/train collisions. See the following links for a small taste: http://koin.com/2014/04/01/1-hurt-car-max-crash-portland/ http://koin.com/2014/04/01/1-hurt-car-max-crash-portland/ http://www.oregonlive.com/portland/index.ssf/2013/06/max_collision_with_car_in_down.html http://www.oregonlive.com/portland/index.ssf/2013/06/max_col... http://www.oregonlive.com/portland/index.ssf/2015/05/max_blue_and_red_lines_delayed.html http://www.oregonlive.com/portland/index.ssf/2015/05/max_blu... https://www.reddit.com/r/Portland/comments/3d5i9g/saw_an_orange_line_maxcar_collision_on_my_bicycle/ https://www.reddit.com/r/Portland/comments/3d5i9g/saw_an_ora... There may be more to it in Portland than "at grade", but that certainly seems to be a large component of the problem.

chris_7 10y ago
From the photos, it looks like bollards would have solved most of these? It's not really a dedicated lane if drivers can just wander into it.