Expo Line - Surrey Langley Extension: Planning & Pre-Construction - Page 389

Helvetia · #**7761** Posted **Mar 22, 2023, 9:22 PM**

Quote:

Originally Posted by aberdeen5698

There's no flyover at the junction just east of Lougheed Mall...

... which is why trains have to wait for the track to clear depending on which direction they're approaching from. The setup at LTC is not ideal for branching and doesn't allow 100% cross-platform transfers like Bridgeport.

Mac Write · #**7762** Posted **Mar 22, 2023, 10:14 PM**

How would you fix LTC so it only uses the center platform and handled the branch lines better?

Helvetia · #**7763** Posted **Mar 22, 2023, 11:03 PM**

Quote:

Originally Posted by Mac Write

How would you fix LTC so it only uses the center platform and handled the branch lines better?

I don't know enough to be sure if LTC can be fixed easily (i.e. no full rebuild), but there's no reason to repeat the "mistakes" of the past. New train lines are expensive, so you might as well get it right the first time.

aberdeen5698 · #**7764** Posted **Mar 23, 2023, 5:54 AM**

Quote:

Originally Posted by Helvetia

... which is why trains have to wait for the track to clear depending on which direction they're approaching from. The setup at LTC is not ideal for branching and doesn't allow 100% cross-platform transfers like Bridgeport.

Of course. But my point is that they've already built one line branch without a flyover (even though it was originally intended to have one) so you can't use the lack of a flyover as an argument that they won't build another branch at King George.

madog222 · #**7765** Posted **Mar 23, 2023, 6:08 AM**

Quote:

Originally Posted by aberdeen5698

Of course. But my point is that they've already built one line branch without a flyover (even though it was originally intended to have one) so you can't use the lack of a flyover as an argument that they won't build another branch at King George.

Originally intended as in circa 2002 or earlier? The flyover as designed when the station was built was just to correct the wrong railing of trains Coquitlam bound, all the current switches would still exist.

Did the earlier north-south aligned station design have full flyovers?
EDIT: As of 1998 it didn't; page 219 https://www2.gov.bc.ca/assets/gov/enviro...roject-reviews/skytrain-final-report.pdf

aberdeen5698 · #**7766** Posted **Mar 23, 2023, 4:18 PM**

Quote:

Originally Posted by madog222

Originally intended as in circa 2002 or earlier? The flyover as designed when the station was built was just to correct the wrong railing of trains Coquitlam bound, all the current switches would still exist.

True enough. Doesn't change the fact that we have a proven "track record" of designing line branches without flyovers, and therefore lack of a flyover at King George is not evidence that there won't be provision for a branch built there.

Helvetia · #**7767** Posted **Mar 23, 2023, 4:38 PM**

Quote:

Originally Posted by aberdeen5698

True enough. Doesn't change the fact that we have a proven "track record" of designing line branches without flyovers, and therefore lack of a flyover at King George is not evidence that there won't be provision for a branch built there.

Fair enough, it would be possible to branch off at King George (though I think it's fair to say neither of us want such a branch).

madog222 · #**7768** Posted **Mar 23, 2023, 6:34 PM**

Plus there are the level switches for the Port Coquitlam spur, those are newer than the Canada Line.

aberdeen5698 · #**7769** Posted **Mar 23, 2023, 7:03 PM**

Quote:

Originally Posted by madog222

Plus there are the level switches for the Port Coquitlam spur, those are newer than the Canada Line.

Actually, I think the only place that we have an honest-to-god flyover is at Bridgeport, which is crazy because the frequencies on both spurs are limited by the single tracking to the last stations. You really gotta wonder why they bothered in a project where they cheaped out on the station lengths...

madog222 · #**7770** Posted **Mar 23, 2023, 7:18 PM**

Quote:

Originally Posted by aberdeen5698

Actually, I think the only place that we have an honest-to-god flyover is at Bridgeport, which is crazy because the frequencies on both spurs are limited by the single tracking to the last stations. You really gotta wonder why they bothered in a project where they cheaped out on the station lengths...

I wonder if being a P3 contract influenced this. Would the extra cost be lower than 30 years of maintenance on two more switches.

There is the split east of Columbia but I wouldn’t really count that (as purpose built) as the bridge approach is being utilized as a flyover.

chowhou · #**7771** Posted **Mar 23, 2023, 8:10 PM**

Quote:

Originally Posted by aberdeen5698

Actually, I think the only place that we have an honest-to-god flyover is at Bridgeport, which is crazy because the frequencies on both spurs are limited by the single tracking to the last stations. You really gotta wonder why they bothered in a project where they cheaped out on the station lengths...

Does the Columbia - Skybridge - Millennium Line extension "fly under" not count?

aberdeen5698 · #**7772** Posted **Mar 23, 2023, 9:53 PM**

Quote:

Originally Posted by chowhou

Does the Columbia - Skybridge - Millennium Line extension "fly under" not count?

It does, forgot about that one!

officedweller · #**7773** Posted **Mar 24, 2023, 12:41 AM**

Quote:

Originally Posted by madog222

Plus there are the level switches for the Port Coquitlam spur, those are newer than the Canada Line.

Agreed - my thoughts too.

Quote:

Originally Posted by aberdeen5698

Actually, I think the only place that we have an honest-to-god flyover is at Bridgeport, which is crazy because the frequencies on both spurs are limited by the single tracking to the last stations. You really gotta wonder why they bothered in a project where they cheaped out on the station lengths...

I think the short trains are exactly the reason why they have the flyovers
- because the flyovers support the higher frequency required (by the smaller trains) to get to ultimate capacity.
The single tracking came late in the process.

madog222 · #**7774** Posted **Mar 28, 2023, 4:11 AM**

Shortlisted contractor teams have been announced for the stations contract.
Surprise! It's the same two teams as were shortlisted for the guideway contract.

https://news.gov.bc.ca/releases/2023MOTI0038-000388

Contract is scheduled to be awarded next year.

Contract for the guideway is due this fall. Shortlist for the track & systems contract should be soon with contract award next year.

Jimbo604 · #**7775** Posted **Apr 4, 2023, 6:06 PM**

Quote:

Originally Posted by madog222

Shortlisted contractor teams have been announced for the stations contract.
Surprise! It's the same two teams as were shortlisted for the guideway contract.

https://news.gov.bc.ca/releases/2023MOTI0038-000388

Contract is scheduled to be awarded next year.

Contract for the guideway is due this fall. Shortlist for the track & systems contract should be soon with contract award next year.

Masstransitmag.com:
British Columbia shortlists two teams for Surrey Langley SkyTrain stations package by Mischa Wanek-Libman March 30, 2023
https://www.masstransitmag.com/rail/infr...surrey-langely-skytrain-stations-package

BIV.com:
Acciona shortlisted for more SkyTrain contracts, despite North Shore Wastewater Treatment Plant turmoil
Metro Vancouver hired Acciona as a contractor in 2017 for the North Shore Wastewater Treatment Plant project, which has been delayed and run over budget By Bob Mackin | March 28, 2023, 9:31am
https://biv.com/article/2023/03/acciona-...contracts-despite-north-shore-wastewater

superelevation · #**7776** Posted **Apr 6, 2023, 1:53 AM**

Quote:

Originally Posted by aberdeen5698

True enough. Doesn't change the fact that we have a proven "track record" of designing line branches without flyovers, and therefore lack of a flyover at King George is not evidence that there won't be provision for a branch built there.

A flyover is great, but you only need one if the frequency of service over the junction is sufficiently high. Assuming Expo has 3 branches with one to LTC, one to Langley, and one to KGB traffic to Langley and KGB may not be sufficient to justify a flyover (I would assume this is part of the justification with the POCO split too - plus you will have additional platforms at Co Central).

The REM in Montreal will only have it's "innermost" junction between the DM Line and the West Island + Airport Lines as a flying junction, the one between WI and Airport is flat.

Migrant_Coconut · #**7777** Posted **Apr 6, 2023, 3:49 AM**

Frequency's only part of the problem. If one of the switches fails, that's two branches out of service and needing a bus bridge.

Helvetia · #**7778** Posted **Apr 6, 2023, 3:56 AM**

Quote:

Originally Posted by Migrant_Coconut

Frequency's only part of the problem. If one of the switches fails, that's two branches out of service and needing a bus bridge.

Ah but that'll never happen. What's the chance a switch fails at a critical point like the SkyBridge /s

madog222 · #**7779** Posted **Apr 6, 2023, 4:01 AM**

Quote:

Originally Posted by Migrant_Coconut

Frequency's only part of the problem. If one of the switches fails, that's two branches out of service and needing a bus bridge.

If a switch fails, in either configuration, it can run single tracked. Having a flyover makes no difference, only two fewer switches to potentially fail.

Migrant_Coconut · #**7780** Posted **Apr 6, 2023, 4:05 AM**

Quote:

Originally Posted by madog222

If a switch fails, in either configuration, it can run single tracked. Having a flyover makes no difference, only two fewer switches to potentially fail.

My bad, I got confused with the OP that mentioned an independent Newton line: that would mean a shutdown on one line wouldn't affect the other.