Fixing bottlenecks

 
  Myrtone Chief Commissioner

Location: North Carlton, Melbourne, Victoria
I didn't realise there was enough space for track amplification without property acquisition, wow, that's a relief.

Maybe when the Sandringham line gets high capacity signalling, we might also want to consider the possibility of termination all stations trains at Brighton beach with trains to Sandringham running limited stop between Brighton Beach and South Yarra.

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  Gman_86 Chief Commissioner

Location: Melton, where the sparks dare not roam!
On to the issues then...

Actually, I think there are some capacity issues on the Clifton Hill section. Almost every morning around 8.40-9am trains are very congested between West Richmond and Flinders St, spending a lot of the time stationary. However, I think this might be due more to the capacity of platform 1 at Flinders St being less than the rest of the line (due to passenger crowding, possible driver changes, and the length of the platform requiring slower speeds to move through).

Not that that means more infrastructure is needed immediately, but...

The PTV network development plan identifies a tunnel from Victoria Park to Flagstaff as the preferred upgrade (to allow for hypothetical Doncaster trains too). Why can't Clifton Hill/Victoria Park -> Jolimont/Flinders St be quadded instead? Every morning as my train crawls through here I can see there is physically enough space along the whole alignment for 4 tracks without property acquisition. Has this been considered? Should be cheaper than a tunnel.
bramt
I'm not convinced there is enough space through here, and real estate is at an absolute premium here, so property acquisition would be cost prohibitive.
  Gman_86 Chief Commissioner

Location: Melton, where the sparks dare not roam!
I didn't realise there was enough space for track amplification without property acquisition, wow, that's a relief.

Maybe when the Sandringham line gets high capacity signalling, we might also want to consider the possibility of termination all stations trains at Brighton beach with trains to Sandringham running limited stop between Brighton Beach and South Yarra.
Myrtone
Sandringham is not likely to be a candidate for two tier services. It's comparitivly short, hasn't got too many stations, and is capable of running at high frequency without impacting on other services. When high capacity signalling is instated this will be even more prevelant.

Express services on the Sandringham line would serve little to no purpose.
  AzN_dj Chief Commissioner

Location: Along route 69
Most of the issues through Jolimont - Clifton Hill are platform capacity at Flinders Street, and mixed services absorbing capacity.
Easy fixes for both - move driver changeovers outside of Flinders street to where you can easily put more platforms (e.g. Clifton Hill), and start cutting express services.
  Madjikthise Deputy Commissioner

What does driver changeover have to do with this?
  Myrtone Chief Commissioner

Location: North Carlton, Melbourne, Victoria
Sandringham is not likely to be a candidate for two tier services. It's comparitivly short, hasn't got too many stations, and is capable of running at high frequency without impacting on other services. When high capacity signalling is instated this will be even more prevalent.

Express services on the Sandringham line would serve little to no purpose.
"Gman_86"


But there are sidings at Brighton beach which could be used by the short working services. How close together are stations typically on that line?
  railblogger Chief Commissioner

Location: At the back of the train, quitely doing exactly what you'd expect.
What does driver changeover have to do with this?
Madjikthise
The time trains spend at the platform while the changeover takes place affects throughput of the platform.
  Madjikthise Deputy Commissioner

The time trains spend at the platform while the changeover takes place affects throughput of the platform.
railblogger
No it doesn't because it takes longer for people to get off and on than it does for the changeover.
  LancedDendrite Chief Commissioner

Location: Gheringhap Loop Autonomous Zone
But there are sidings at Brighton beach which could be used by the short working services. How close together are stations typically on that line?
"Myrtone"

Can you please do your own research for once?
http://vicsig.net/infrastructure/line/Sandringham
  Myrtone Chief Commissioner

Location: North Carlton, Melbourne, Victoria
That page doesn't mention much, and what it says about Brighton beach sidings is dated. And no, it gives me little indication about whether it would be a candidate for two-tier services.
  LancedDendrite Chief Commissioner

Location: Gheringhap Loop Autonomous Zone
Look at the milepost distances that are listed for each station on that page. They're all distances relative to Flinders St, so you can subtract those distances from each other to get the distances between each station on the Sandringham Line. Now go away and come back with some numbers. I'll wait.
  Myrtone Chief Commissioner

Location: North Carlton, Melbourne, Victoria
Why me, and not anyone else do the maths? I didn't notice the mileposts. Be kind to the OP please.
  Gman_86 Chief Commissioner

Location: Melton, where the sparks dare not roam!
Why you? Because your the one who asks the stupid question, and then disputes the answer with another stupid question. That's why you.

Just because there are stabling sidings at Brighton Beach, that doesn't automatically justify short starting services from Brighton Beach and semi-express services from Sandringham. Like I said (and you ignored), anong other reasons, the Sandringham Line is too short to justify a two tier service.
  Myrtone Chief Commissioner

Location: North Carlton, Melbourne, Victoria
I'm not ingoring that, the Sandringham line isn't that short, it is still longer than the former railways to Port Melbourne and St. Kilda. It still runs beyond the territory of our tramway network, for example. It may be shorter than say, the Frankston line. Is it really the shortest suburban railway in the Melbourne area? If so I didn't realise that, though it does reach Zone 2.
Those sidings at Brighton Beach do have platforms, so they could be used for as a terminus for some serivces, and I guess they were originally served as such.
I don't see what's stupid about the question, the answers probably aren't obvious to the general population.
  Gman_86 Chief Commissioner

Location: Melton, where the sparks dare not roam!
While the question in itself isn't that stupid, your attitude towards a thoughful and considered response was immensely stupid. But here it is with even more depth: No the Sandy line isn't the shortest in Melbourne, in fact here's some distances (all measured from Flinders St Station, stations counted not including city loop stations, or North Melbourne and Richmond) that I found in just a couple of minutes myself, using the same website linked above that you suggested was next to useless:
Williamstown    14.204km 9 stations
Alamein           16.12km  12 stations
Upfield            18.85km  13 stations
Sandringham    19.16km  12 stations

Comparisons to the former lines to St Kilda and Port Melbourne are irrelevant, they don't exist as heavy rail anymore for exactly that reason.

The difference between Brighton Beach and Sandringham is barely over 3km and contains only an extra 2 stations, so their is little to be gained by stopping a service short at Brighton Beach over just continuing on to Sandringham. Yes Brighton Beach does have a 3rd platform (platform 1 to be exact) but this hasn't been used for regular services for a long time, for the reasons above.

As for having a little respect for the OP, the OP was related to fixing bottlenecks, an issue that is not relevant to the Sandringham line.
The reason you should be expected to look up some of your own facts are due to the fact that you are the one seeking them, and they are available to anybody who can be bothered to look for them, proof is the above information that I managed to find quite easily. Why should we have to do it to prove your point for you?
  Myrtone Chief Commissioner

Location: North Carlton, Melbourne, Victoria
Thank you very much for posting the information, I didn't say the site was next to useless, just that page didn't seem useful, judging from the two pargraphs at the top of the page, I didn't think to look further down. It does mention the distance of each station from Flinders street I acted the way I did because I thought I'd mention the sidings as a terminus. It wouldn't be a case of running two tier serivces all day, maybe just occasionally.

One thing I did notice from looking at a map is that there are two pairs of stations (Prahran-Windsor and Balaclava-Ripponlea) that are quite close together and I was thinking of those when I thought of having two tier services on that line.

Sorry for the inconvenience but it didn't seem worth my time and effort to calculate the station spacing from the information given. I only brought it up because someone mentioned that high capacity signalling is to be trialled there soon. Increase in signalling capacity and fixing (physical) bottlenecks are different things.
  ZH836301 Chief Commissioner

Location: BleakCity
I'm not convinced there is enough space through here, and real estate is at an absolute premium here, so property acquisition would be cost prohibitive.
Gman_86


There isn't, that's why long term plans are for a new tunnel towards the city.

No it doesn't because it takes longer for people to get off and on than it does for the changeover.

Don't use rubbish arguments to try and support an archaic practice.


Why me, and not anyone else do the maths? I didn't notice the mileposts. Be kind to the OP please.
myrtone

  bramt Deputy Commissioner

>I'm not convinced there is enough space through here, and real estate is at an absolute premium here, so property acquisition would be cost prohibitive.
There isn't, that's why long term plans are for a new tunnel towards the city.
ZH836301
Are you sure, or is this based on observations?
If the latter, I challenge your observations against mine! Have a look at the bridge abutments at Gipps St: space has been allowed for an extra deck on either side of the existing one.

I said there's physically enough space for 4 tracks between Clifton Hill->Jolimont. It would be tricky between Victoria Park and West Richmond, because it would mean the whole embankment would need to be rebuilt in order to be widened. ~2-3m high retaining walls would need to be built along the length, so a more sheer elevation could be built. (currently it is just a sloped embankment in many places). Luckily, space around the stations (where it needs to be wider) is available: Victoria Park has the huge vacant siding area, Collingwood has the town hall on one side and a park on the other, and North Richmond has Victoria St and 2 other one-way streets either side of the station platforms, meaning it could, in theory, if necessary, be widened and decked. Or just demolish Jonas St (which has no residences on it anyway, just parking access for Mercy Health) and make Regent St 2-way.

Not saying it would be cheap, just possible. But the city->Sunshine section of Regional Rail Link had similar challenges, and that part certainly cost less than a tunnel from Victoria Park to Flagstaff would.
  Nightfire Minister for Railways

Location: Gippsland
Are you sure, or is this based on observations?
If the latter, I challenge your observations against mine! Have a look at the bridge abutments at Gipps St: space has been allowed for an extra deck on either side of the existing one.

I said there's physically enough space for 4 tracks between Clifton Hill->Jolimont. It would be tricky between Victoria Park and West Richmond, because it would mean the whole embankment would need to be rebuilt in order to be widened. ~2-3m high retaining walls would need to be built along the length, so a more sheer elevation could be built. (currently it is just a sloped embankment in many places). Luckily, space around the stations (where it needs to be wider) is available: Victoria Park has the huge vacant siding area, Collingwood has the town hall on one side and a park on the other, and North Richmond has Victoria St and 2 other one-way streets either side of the station platforms, meaning it could, in theory, if necessary, be widened and decked. Or just demolish Jonas St (which has no residences on it anyway, just parking access for Mercy Health) and make Regent St 2-way.

Not saying it would be cheap, just possible. But the city->Sunshine section of Regional Rail Link had similar challenges, and that part certainly cost less than a tunnel from Victoria Park to Flagstaff would.
bramt
The problem than become what do you do with the extra 2 tracks from Jolimont Into the City.
  LancedDendrite Chief Commissioner

Location: Gheringhap Loop Autonomous Zone
Quadding Jolimont-Clifton Hill would only really would shift congestion towards Flinders St (although the separation of express services would definitely be positive). That's the main reason for the proposed tunnel: to completely separate Mernda line services from the rest of the network whilst still providing a connection to the CBD.

The costs of quadding + extra congestion relief Jolimont-Flinders St are your baseline. Comparatively the Southern Cross-Rushall tunnel proposal provides additional benefits, such as an expanded passenger catchment and better network separation. Costs would probably end up being more, but that's what a proper cost-benefit analysis should be for.
  Heihachi_73 Chief Commissioner

Location: Terminating at Ringwood
Nothing to be said about the single-track bottleneck on the Belgrave line? It takes half an hour just to get to Ringwood, and then another fifteen minutes to Box Hill before the train even thinks of skipping a station. Unlike Pakenham, ignoring the now-closed whinging thread, Belgrave never had a V/Line service to fall back on, and also has 30 minute off-peak services and a large single-track section for most of the line (Ferntree Gully to Belgrave, not counting stations which are also used as crossing loops - Tecoma being the odd one out with only one platform and no crossing loop).
  AzN_dj Chief Commissioner

Location: Along route 69
If there were enough space for four tracks between Clifton Hill and Flinders street, they wouldn't have screwed up the entrance to the City Loop, would they? It would have been a centre portal, not a portal on one side, which was the whole reason why Jolimont went to no loop reversals on weekdays (less traffic on Weekends hence why they can switch the directions. However if there were a Doncaster line, I would have my doubts).

Two tier services on Sandringham would save, what? three minutes tops? It's not worth wasting money to save three damn minutes, which your train would probably be delayed more than that anyways. You cut capacity for no good reason. More trains stopping all is the best thing you can do for the line. Maybe extra platform at Sandringham.

And of course changeovers take longer than it takes for passengers to get on and off - you could offload a peak hour train in twenty seconds or less. Melbourne Central at points experiences more people disembarking than Flinders Street, yet does so in twenty seconds. If there were space at Flinders Street, Bifurication would make sense. However, heritage requirements, land constraints blah blah blah, easier to shift bifurication outwards and reduce stopping time at Flinders street to twenty seconds. And other reasons to have layover times such as slack to allow timetable to recover blah blah blah.
  bramt Deputy Commissioner

If there were enough space for four tracks between Clifton Hill and Flinders street, they wouldn't have screwed up the entrance to the City Loop, would they? It would have been a centre portal, not a portal on one side, which was the whole reason why Jolimont went to no loop reversals on weekdays (less traffic on Weekends hence why they can switch the directions. However if there were a Doncaster line, I would have my doubts).

AzN_dj
Pretty big call to say it's screwed up only because there wasn't space to do it properly. They can screw things up even with lots of space!

There is actually plenty of space to the south: there is a linear park between the tracks and Wellington Parade South. I suspect the reason the portal was built to the side rather than between the 2 tracks like all the other loop portals is more to do with gradients.
The roof of the existing portal is actually still above the height of the tracks to Flinders St, so it would have had to been a few metres deeper in order to go between the Flinders St tracks. The current portal ramp track crosses the first road, Jolimont Rd, just below the height of the Flinders St tracks.
So these are the design constraints: if you go a few metres deeper to get the portal between the tracks, you won't have enough horizontal distance to raise the height enough to clear Jolimont Rd
  ZH836301 Chief Commissioner

Location: BleakCity
Are you sure, or is this based on observations?
bramT

If your assumption on the ability to take four tracks is based on (half) a quirky overpass you are sorely mistaken.
  AzN_dj Chief Commissioner

Location: Along route 69
Pretty big call to say it's screwed up only because there wasn't space to do it properly. They can screw things up even with lots of space!
bramt
It could have probably been done, just at a higher cost. It did screw with the network in the AM peak, but yes, it probably is an exaggeration.


If your assumption on the ability to take four tracks is based on (half) a quirky overpass you are sorely mistaken.
ZH836301

A quick flyover view on Google maps suggest that there is no space available at any of the station locations, north of North Richmond, or the tunnels.

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