High speed lines taking inordinate amounts of passengers off other lines

[Fermiboson]

I understand that under the current system passengers simply select the route which takes the shortest time from origin to destination. However, it seems that this is causing problems where the construction of a high speed line will take everyone travelling in that vague direction off conventional lines and onto the high speed line, hence emptying the conventional lines and overcrowding the high speed one. e.g. in my BR save with HS2 phase 1, passengers from Bristol to Derby take the GWR nonstop from Parkway to OOC then HS2 to Brum. Nobody is actually going to do that in real life. LNWR have completely run out of passengers, Euston is deserted (because everyone gets on at OOC), while the HS2 400m units are crush loaded even at midnight.
Is there any fix for this currently other than lowering the speed of the high speed line to just above conventional line speed? Alternatively, is it currently within the dev's purview that passengers would take cost into account when choosing their routes (ideally, the relative probability of a passenger choosing a route would be something like 1/(1+cost*time))?

[Overlag]

I have the same problem. I can run a HST every 2minutes and its still not enough. Most of my HS stations are over 10000 passengers waiting, which takes until 2-3am to clear.

[Sherminator]

same here,
people prefer to wait 50 Minutes at a station for the high speed train instead of boarding the commuter train which arrives 45 Minutes earlier. The commuter train would arrive 1 minute after the high speed train at the target station an has plenty of free seats. Of course the high speed train train arrives packed at the station an so noone is able to enter the train.

Maybe one could intrdouce something like a "train app" for passengers who can check in advance how full the arriving trains will be approximately and have the option to take alternative connections acoording to the chances of beeing able to board the train?
Or alternatively "book seats" in trains in advance an if the train won't have free seats then the train will drop from the available connections at a station so people won't wait for nothing and instead plan the trip with other connections.

[djplong]

I had a similar problem. My Northeast Corridor line from Boston to New York was overcrowded with pax getting off at stations still within the 'regional rail' coverage.

I used the "Board only" flags for the HS line at those stations so that pax could not take up a seat from Boston, 10 miles to Canton while leaving a Boston-New York passenger waiting in Boston.

For some through services, that can be a little more complicated but I see that a "minimum time traveled" value has been created and that can stop some of those short-timers taking up space if you have, say, a 1-hour minimum allowable travel time for pax.

[WanderingVermonter]

Could implementing something like pax boarding priority is given to those that travel further on the route or complete a higher percentage of the route overall? That may allow those that need HS to get farther along the route to board ahead of those that could just take a non-HS train from the same departure stations.

[Fermiboson]

In this post I'm not specifically referring to express trains running along the same line as regional trains being overcrowded, mainly because there is a known bodge fix (min ride time) and because the overcrowding does occur IRL (e.g. in the UK XC Brum to Wolves and XC Basingstoke to Reading) (though my proposed fix would also help with that problem). I'm referring to HS lines taking passengers off not just adjacent lines, but lines it has clearly no business affecting - in no world is HS2 going to take passengers off XC routes. To take an American example, if you have an express service from say Boston to DC nonstop and a HS line from DC to Chicago, nobody is going to go from Boston to Chicago via DC, even if it is technically faster by a few minutes, and even if they're on expenses.

I don't like the idea of compulsory reservation trains (ref. France's TGVs) in general, and I suspect it would be computationally very expensive to implement in game because one would have to iterate through all potential trains on the route. It could also lead to runaway overcrowding. I propose the probabilistic redistribution of passengers because it seems to me to be a low cost method (every passenger already has to be iterated through and do a pathfind, and calculating a cost is O(1) for every route - and for most networks realistic routes will be limited to a small number). I'd be very glad to hear any comments the dev has on this.

Alternatively, if anyone currently has a bodge fix that restores somewhat realistic numbers to HS and conventional networks, I'd be glad to hear it as well. Currently all I could do is lower HS2 line speed to 280kph so that the journeys are slow enough no longer to be attractive to passengers farther from the line but still attractive enough to take pressure off the WCML.

[adlet]

Originally posted by Sherminator:

same here,
people prefer to wait 50 Minutes at a station for the high speed train instead of boarding the commuter train which arrives 45 Minutes earlier. The commuter train would arrive 1 minute after the high speed train at the target station an has plenty of free seats. Of course the high speed train train arrives packed at the station an so noone is able to enter the train.

In addition to managing stop board only/exit only and minimum time settings, one other thing you can do is to work with the timetable. For example in the above case if you move the high speed departure time by 2 minutes, the arrival time to destination would be later than the commuter train.

Another idea for commuter vs. high-speed is semi-express trains, these run the same lines as commuter but gain time by skipping some stops. This also helps serve stations further out.

It is also true in real world though that high speed lines cannibalize conventional. In Japan whenever a new shinkansen line is opened, the existing conventional lines are significantly reduced in volume of seats, part of it to actually force passengers to ride on higher-price shinkansen.

It's hard for me to imagine how fast HSL lines would need to be to get from Boston to Chicago via DC faster than on a direct line - but if one built such fast lines from DC to both of those cities, one can also build a direct link from Boston to Chicago too. This to me is a challenge of planning and building an efficient network. That's what airlines do for example - since they can't connect every city to every other city, they identify where to place convenient hubs and traffic naturally goes through them.

[trolley_trev]

In my mind, the simple solution is to introduce a train change penalty to the pax calculation. The higher the penalty, the more change averse pax are. Unless the HS service and subsequent changes will save more time than all the change penalties incurred, pax will prefer a slower option with fewer (or no) changes. Obviously, this penalty value needs to be user configurable to find the right balance for each player's individual network.

Ultimately, I would love to see a way of adjusting the change penalty based on the type of service change. For example, a cross-platform or same platform change is far less onerous than getting from platform 5 to platform 20 at a large terminus. But I don't know what the logistics of implementing that would be from a development perspective.

[AkalaMangala]

I am for adding a time and cost function that probabilistically determines a pax path as the low-cost solution. In my fantasy world though, I would like passengers to also have a way to determine whether they can board a train and choose their route accordingly. Maybe you don't implement this at every node on the path, but you already have all the data available to make this a function for the origin station.

[adlet]

One other consideration here. This is a game. As in any game, you try to perform to score best. No points here, but there are dollars and informal criterion of how well networks operate. Every game has its limitations and rules, not always realistic and not always well known. We at least know the rule here for pax, it's the quickest path. So as in any game (or life) we make decisions on where to build, what service to introduce, etc. The environment then reacts - in this case by ridership patterns. So if the patterns are not as expected, as players we can change the approach, add services, add lines, redesign operations, etc. Especially since the rules are known and especially if you build your own network, not tied to any existing real life services. That's this game's strategy challenge.

For example, 1.12/1.13 brought in walking connections and my Tokyo tram line became connected to the nearby heavy rail line and so many passengers decided to transfer, it was way above tram line capacity. I could have upgraded the tram line to higher capacity, but it's a real network, so did not want to do it. So I changed my order of adding lines to the network and prioritized building another heavy rail line that would connect to tram from the opposite end. For this new line I decided to add 12 stations only for now (of the 40+ in real life) - to the depot - as I don't want to spend too much time on it, but 12 stations allows to have a meaningful traffic and add revenue. (The tram line connection would have been only 4 stations). Looks so far like the tram line issue has been solved, though I have not yet tested a Friday. So the point is, you have many tools as your network manager to address the challenges, that's effectively the game's goal and fun.

[MirkoC407]

Indeed, and don't forget we have new rules on traffic patterns as well. In my fictitious North Spain / South France network centred on Barcelona, there is a complete Barcelona with metro and trams, most (but not all) commuter lines, and high speed lines from Barcelona to:
1. Saragossa - Vitoria - Bilbao - Gijon
2. Saragossa - Madrid
3. Saragossa - Burgos - Leon - Gijon
4. Girona - Toulouse - Bordeaux
5. Girona - Montpellier - Saint Etienne
6. Valencia - Alicante - Murcia - Cartagena
Also a high speed line is connecting Bilbao and Vitoria with Bordeaux and Toulouse to avoid passengers from Bilbao to Bordeaux going the horseshoe shaped route through Barcelona

On the old "a station creates maximum passengers and assigns a destination" system the commuter and metro lines running into Barcelona Sants station were overcrowded so much that I considered to open the (being built in reality as well) second high speed station in the north of Barcelona to split the demand. Then the trains became quite empty outbound, never were high speed trains overcrowded into Barcelona, but always out.

With the new "tile to tile demand is created when covered by a station" approach the metro and commuter lines in Barcelona are fine. But now high speed lines are permanently overcrowded, because due to the distance demand two things happen:
1. Passengers use high speed trains for regional traffic, basically the whole chain Barcelona - Girona - Figueres - Perpignan - Narbonne - Beziers - Montpellier - Nimes is clogged with regional passengers, not leaving space for the target population.
2. Routes that did not play a role before because it was a low probability one suddenly get more passengers. Like from Madrid to Alicante, Valencia or the other side Leon, Burgos, etc (which is all under 300 km and generates statistically much more passengers now). The trains from Madrid were running nearly empty, now they are overcroweded, why I built a new line directly from the Valencia - Alicante section through Madrid to meet the Burgos - Leon line in Palencia and further on to Vitoria and take passengers off from the Madrid - Saragossa section as well as Barcelona - Valencia, Saragossa - Bilbao and Saragossa - Leon. And the next project is the conventional line Barcelona - Montpellier so I can block regional passengers from the high speed trains there.

We might also rethink old building patterns to adapt to the new passenger generation rules.

[adlet]

Yes I also find the building strategy is almost the opposite now. Which has been a blessing. The demand patterns changed in 1.9 (I think it was?) and now again in 1.12-1.13 - and both times it was a big improvement. Yes new hot areas came up, but they made a lot more sense and actually tied to reality. I had to keep the Tokyo Arakawa tram line and Fuji-Kyuko train line disconnected from the remaining lines before 1.12, as both were getting overwhelmed - but now they both operate fine, though Sakura line required to build a new transfer point for this to work. I was able to operate before with 30-50% of real-time trains on my two major lines, but now I had to buy trains to real-time number to deal with demand. I am using real-time timetable though, so it actually validates that what works in real life reasonably well, should work in NIMBY too.

The default distance demand in NIMBY I do find needs adjustment. Even on Tokyo where I have a working shinkansen line to Osaka I dropped every value over 50 km to ~1%.

Mirko, by the way there are good quality discussions and a great group of very knowledgeable folks on the Discord site where I have been spending time recently. You can get in through the invite in the pinned message from WaW.

[MirkoC407]

Should I finally need to join Discord? Until now I could avoid having another communication platform ;-)

[adlet]

I think it's the same user name you'd use. It's just there's been a lot less activity on this forum of late.

[TKR]

you can bar passengers from boarding HSR for short trips. give them a minimum ride time in the line edit window.

[MirkoC407]

Originally posted by TKR:

you can bar passengers from boarding HSR for short trips. give them a minimum ride time in the line edit window.

I know, but it would only increase my problem until a parallel line exists. Because as I understand you don't erase these passengers from the map. If they are not allowed to go to the next station, they will go to the third next (clogging up the train for 3 stations instead of 1 they were on anyways) and then the train back for another 2 stations (they would otherwise not have been on, clogging it up as well). This ban only works if an alternative is available, otherwise it makes the mess only bigger.