[pierreh]

(I was going to comment on Spooky's latest post, but the quote option doesn't seem to work for me, or I don't understand how it should be used. I postpone my comments).

In the edit part of my latest post I mentioned that the pictires shown didn't reflect the proper situation in Desognes. Actually, on hindsight, I should simply have removed that post. Since it is still there, here are better pictures.

The positioning of the 2 intercity subway links between Desognes and Marlande, seen in Desognes, is as follows:



1 is the older link, 2 is the more recent link. It can be seen that the old link arrives 'outside' of the current commercial zone and connects to the rest of the subway/GLR network at an extremity of that zone. The new link is better positioned, connecting more directly with the center of the commercial zone.


Traffic on the old link has been decreased and the link is no longer saturated. The link is used in both directions, but the bulk of the usage is Sims coming from Marlande to go work in various commercial buildings; buses are used in some cases to complete the commute. Usage in the other direction is very minimal.




Traffic on the new link is still relatively low and has potential for growth. Similarily to the older link, the new link is used mainly by Sims coming from Marlande to work in the commercial area of Desognes, whereas traffic moving in the other direction is very low:




The intercity subway connections in this case are now considered as under control and I'll turn my attention to other cities in the cluster.

[brian51]

I think its the game. I never had much success getting it to work as intended to help reduce congestion when I made the efforts many times years ago.


See now I have had the opposite experience with using U - rail
maybe one of these days I will have to put together a CJ post on this to document what i was able to do

And now on to Pierre's postings -

Yes this was a very nice post...
I am very glad that this has worked out so well for you. Because I think as some people know traffic situations can be quite complicated and so when something like this does work as intended , its to be appreciated

[Guardian]

See now I have had the opposite experience with using U - rail
maybe one of these days I will have to put together a CJ post on this to document what i was able to do

I'd be curious to see what you did and how you went about it. Always love traffic improvements. 

@Pierreh: How many stops do you normally make on a subway line? I always think real world implementation and understand outside of the games most subways don't actually have many stops per line. In-game I always seem to overdo it.

[pierreh]

@Guardian: The number of stops on a subway line depends on the length of the line. It is therefore more meaningful, I think, to look at it in terms of average distance between the stations. Clearly in the game, or at least in my cities, subway stations are closer to each other than in real life cities (*). It will probably be useful to show some examples of my CBDs with their subway implementations. I will not go into a 'subway rant' like I did in my previous CJ on Simmania, but I'll mention some of the shortcomings of the subway implementation in SC4. This will be done shortly.

(*) In RL cities it also depends on the density of the city. For example, in intra-muros Paris, that is a very dense city, the subway network was laid out in such a way that - with a few exceptions - no point in the city is more than 500 meters (about 1500 feet) away from a subway station. In more modern subway networks the distance between the stations tends to be longer than in older implementations.

@Brian: I am also interested in your underground railway implementation, so if you can put something together about that it will be welcomed.

[brian51]

Thanks for your comments guys on U rail !

One thing that makes it hard to use U - rail ( although i suppose this factor is no harder than using tram in road, for instance ), is that none of the network is draggable except for ESURE,  , if you guys ever used ESURE much ?.. It can also be argued that ESURE really isnt true U - rail , since it relies on the subway network for much of its functionality.. I would say though in some of my oldest cities , I used ESURE the most if you mean wide spread usage. Although in later cities I did also use U rail even besides ESURE..

Anyways , I will look around in my cities when I get some time and see if i can find some "image" examples of U rail construction soon

[Guardian]

(*) In RL cities it also depends on the density of the city. For example, in intra-muros Paris, that is a very dense city, the subway network was laid out in such a way that - with a few exceptions - no point in the city is more than 500 meters (about 1500 feet) away from a subway station. In more modern subway networks the distance between the stations tends to be longer than in older implementations.

Wow, I had no idea! That seems so short! Especially knowing the modern implementation of it.

[Darth-Apple]

I'd be interested in reading about your thoughts on SC4's subway system.

I have used Washington DC and New York City's subway systems both. NYC had a decent subway in Manhattan, albeit very difficult to understand do to its complexity, but it was never difficult to walk to a station. In some of the other boroughs it can take a little more walking, but it's still an amazing system.

Washington DC's was much easier to understand and much simpler, but was also significantly busier and it generally took much more walking. The last time I visited DC I opted just to drive to avoid the inconvenience of having to mess around with the subway. As bad as traffic was, it was often still faster than having to walk a mile or more to a station.

In my cities I always littered the city with subway stations just about as often as I could. It was inconvenient because they all took a 1x1 square out of my cities, but sims seemed quite discouraged to walk very far. And as expensive as it was in the game, I never seemed short on cash.

Very interesting updates indeed, please keep us posted.

[Guardian]

Washington DC's was much easier to understand and much simpler, but was also significantly busier and it generally took much more walking. The last time I visited DC I opted just to drive to avoid the inconvenience of having to mess around with the subway. As bad as traffic was, it was often still faster than having to walk a mile or more to a station.

Very much a problem with DC. Traffic is terrible and the public transportation system does very little to alleviate it. It is unfortunately not a public transit friendly city. We sat at the end of a line for two hours once trying to get to a baseball game. We got there in the 7th inning. Terrible experience, and afterwards we just drove when we needed it. 

Still avoid DC like the plague because you can get "lost" in traffic for hours and can't get out.

[SpookyZalost]

@ guardian, you have to remember Washington DC was never designed to hold as many people as it does, let alone for anything other than pedestrian and horse + buggee traffic. the design was brilliant and efficient in it's time but time has since made it inefficient and obsolete

[pierreh]

In reply to Darth-Apple's note: "I'd be interested in reading about your thoughts on SC4's subway system.": as I said earlier, I don't want to repeat here the entire lengthy 'subway rant' that I once posted in the previous version of this CJ on Simmania. However, I'll put here some essential points.

It seems (from ancient posts in Simtrop and SC4D forums) that the Maxis developers didn't have enough time to produce a better subway implementation than what we have in the game. Whether this is accurate or not, the implementation has, imho, the following shortcomings:

1. It is essentially a 'flat' implementation, that is, there is a single underground level for all subway tunnels. This means that intersecting tunnels cross each other 'at grade'. This, in turn, means that the intersection of tracks is the same as that of intersecting GLR tracks with a 'grand union' layout at the intersection, allowing to go to 3 directions (straight, left and right). Then, when we see this in the underground view:



The tracks in the tunnel have a layout identical to those of a GLR intersection with a 'grand union':



This, of course, is never implemented in the tunnel of subway networks in RL, because of the obvious problems of security and the reduction in speed, obligation to stop at signals before the intersection, etc.

In RL, when 2 lines intersect, they do this a different levels, that is, one of the lines passes underneath the other. Here is an example extracted from the track map of the Paris metro:



The blue line (Line 2) crosses the brown line (Line 11) at the station Belleville. The map shows that the blue line is on the upper level, and the brown line passes underneath it at the lower level. Each line has its own set of platforms,

The ESURE project, which is currently being discussed in Brian's Transit Mania CJ, was started to overcome this 'one-level' limitation. Unfortunately it wasn't developed sufficiently to allow a wide-scale usage. I found extremely few situations in my cities where I could implement it in a 'natural' way.


2. The 'stations' in the Maxis implementation are represented by the 'subway square' visible in the subway view in the game. There is no notion of actual platforms. I use that square as intersection between lines (limited to 2 lines). The same 'grand union' effect as shown above exists in the subway square, but I like to think that it is not trains that go from one line to the other one, but subway users that change trains. Here is a typical intersection 'under' a RTMT bus+subway combo station placed on a road (surface level view and subway level view):



The fact that it is not possible to bring more than 2 lines into a subway square limits considerably the possible layout of subway tracks - if one wants to remain
as realistic as the game allows.


Fortunately, there is a feature in RTMT that can be used to overcome that limitation, where feasible: the RTMT Avenue Subway+Bus combo stations cover a 2x2 area, in other words, 4 tiles. All those 4 tiles are part of the 'subway station', even when only one of them contains the subway square. One can take advatage of this to bring more than 2 lines into the station, and to place double tunnels between stations on avenues on very busy lines. Here is an example with double tunnels in one of the cities in the cluster:




(The query sign for the station contains 'STREET', this is a bug that will be fixed in the official RTMT Version 4; the station is placed on an avenue).


I can't resist the pleasure of showing one of my favorite subway pictures: the intersection of 3 lines of the Paris metro, near the station Opera. The picture is taken on the line at the lowest level; the second line crosses above it on the middle level, and the undergirders of the bridge carrying the 3rd line can be seen on top of the picture:



This intersection was built 'in advance' when the first of the lines was constructed; the two other lines came later. This piece of engineering work is now over a century old.


I hope that I have answered the query properly. Since subways are a favorite subject of mine, if there are more questions I'll be happy to reply.

[brian51]

Pierre,

I would like to thank you for your informative subway posting. it was a most interesting read...

I just wanted to add a comment here to your segment of intersecting subway tubes, where you also provided an interesting pic-

1. It is essentially a 'flat' implementation, that is, there is a single underground level for all subway tunnels. This means that intersecting tunnels cross each other 'at grade'. This, in turn, means that the intersection of tracks is the same as that of intersecting GLR tracks with a 'grand union' layout at the intersection, allowing to go to 3 directions (straight, left and right). Then, when we see this in the underground view:

There is however an exception or an alternative to this that few players know about...
Part of the ESURE mod does supply something for players called " express subways"
Where a player can use a special TE piece ( i forget whether you sue a FURL or SURC to implement this )..
But what it does is allow you to avoid any turns at intersecting subway tubes and all the player to just go in the intended "straight" direction

Perhaps this is an option is something we can research further , since I have seldom used this subway option in the past ?

[pierreh]

Brian, if you read my previous post attentively you can see that I made the following reference to ESURE:

"The ESURE project, which is currently being discussed in Brian's Transit Mania CJ, was started to overcome this 'one-level' limitation. Unfortunately it wasn't developed sufficiently to allow a wide-scale usage. I found extremely few situations in my cities where I could implement it in a 'natural' way."

In his documentation Steve mentioned a possible implementation of ESURE to creare "express subways", but this was only an example. ESURE can indeed be used to have 2 intersecting subway lines cross each other with an 'two-levels effect', in that one of the lines is transformed from subway to underground rail and back to subway, so that at the intersection you have a subway line crossing an underground railway, with no interference between both. I am entirely aware of this possibility, and as I wrote previously, I managed to use it in one city, where the layout of the roads and of the subway lines allowed it.

My point is that there are only a few pieces in ESURE, which make it difficult to implement such crossings, at least in the cities that I build. If I remember correctly it was Steve's intent to develop ESURE with more pieces, but this never happened, so that we are left with only a very partial implementation of what could have been a very useful add-on in the game.

[Darth-Apple]

Very interesting reading, thank you @pierre.

I do have a question. With the ESURE project for express subways, do sins end up preferring these routes over traditional routes for reasons aside from congestion itself? (In other words, are they faster beyond merely being more efficient?)

And if you were to have two fairly parallel subway lines (maybe a block or so apart), will sims go towards a less congested line even if it is a further walking distance?

Regards,
-Darth

[pierreh]

@Darth-Apple: The ESURE project is described in this thread in SC4D: http://sc4devotion.com/forums/index.php?topic=7397.0. The 'ES' letters in the acronym refer to 'Express Subways', a notion that in RL, to my knowledge, has been only implemented in large scale in the New York City subway system. Essentially, 'Express Subways' are subway trains that do not stop at all stations; they run on their own tracks, that have platforms only at selected stations (in principle every 3rd or 4th station of the normal lines). The express trains do not run faster - or only marginally so - than the normal trains, but their commercial speed is faster because they do not have to break to a stop, dwell for passenger exchange and re-accelerate at every station.

In the game, there is only one category of subway, so there is a single 'speed' and a single capacity for any subway, regardless of how many stations it has. ESURE can simulate express subway lines, by having less stations than normal subway lines, but the capacity is the same for both types of lines. It is then a matter of where Sims can enter and exit stations of the 'express subway' lines, in comparison to normal subway stations. It can surely help to carry more Sims, but to what extent, it is difficult to say.

I am not sure to which extent Sims will use a less congested subway line running in parallel to a congested one. Where I have implemented parallel subway lines in my cities, I have noted that there is a tendency to 'even out' the load on those lines as game time passes. All this is managed by the Traffic Simulator; as cities grow, the work of the simulator increases. There is an excellent tutorial about it in the SimCity wiki: http://www.wiki.sc4devotion.com/index.ph..._Simulator. I have tried to build my cities while keeping in mind the explanations in that tutorial, not always successfully.

[Darth-Apple]

Ah, makes sense. I noticed that about NYC's subways. It was overall well designed in manhattan, but outside of manhattan it could be confusing to figure out which lines went where. I was always curious how the subway lines in SC4 worked for the traffic simulator.

None of my lines ever got too congested to where I needed to really worry, but I generally ran a fair number of them in parallel just because it was easy to set them down. Your subway lines are all very interesting and well designed. I'm impressed with how much of the general proportion of traffic you have been able to route through the subways.

Thank you for the post. Very interesting read.

[pierreh]

Here is a continuation of the discussion about commuting and the use of subways in the Talaran cluster of cities. A goo example is provided by the city of Marlande. This is a global view of the city:



The corresponding zone view is as follows:



The very large commercial area occupies the center of the city are and extends to the south. The largest residential area is on the northeastern side, separated from the commercial zone by a relatively narrow river.

This disposition imposes crossings of the river to link the northeastern residential area to the commercial area. This is achieved by 3 avenue bridges, 1 road bridge, 1 railway bridge and 8 subway tunnels.

The car load on the avenue and road bridges is quite light; the use of buses is extremely low and restricted to the road bridge:



The railway line is used for local commuting: it links a train station in the middle of the residential area, to the main train station in the center of the commercial area:



The bulk of the commuting between the residential and commercial areas is done by the GLR/subway network. The GLR is predominant in the residential area, there are are GLR-to-subway transitions close to the river, and the river is crossed by 8 subway tunnels that continue into the commercial area:



The respective usage figures in those tunnels (all figures are for the morning commute) are as follows:



The very large usage of the subways, relatively to the very limited usage of the avenue and road bridges, is caused by the use of the 'Ultra' variant of the traffic simulator, that variant favorises the use of public transportation - probably to an extreme degree as shown by the above pictures and figures. Since the northeastern residential area is entirely built, the number of commuters crossing the river is expected to remain quite stable. There remains a limited amount of space for residential housing in the southwestern part of the city.

-------------

In general I am not too happy with the implementation of airports in the game, so that I tend to place one airport in each city and then more or less forget about it. Out of curiosity I checked the airport in Marlande and found out that it isn't used at all:



I can't explain why this is so; if someone has an idea or a tip I'll be quite obliged.

[brian51]

Firstly, I really like Marlande.. the layout of the larger river + the 2 smaller rivers you have here is a favorable set up to me

I like the location of your CBD.. in fact i am quite sure that is where I would have placed this also

I really like how you used the subway system and it seems you have an excellent balance with using 8 subway tunnels  for handling the traffic..

I think it was about what i was expecting compare to how many use your road systems..

on the airport non function :

I have noticed this type of thing in my cities sometimes also. It seems to happen most often when I first start playing, but it goes
away as i run the city longer.. Try doing this Pierre , and please let us know if this solves it ?

[Guardian]

The layout is much cleaner than what I can pull off. I have to make it patchwork to get it to function. I guess that's what happens when your transit skills aren't great.

Keep it coming pierreh!