Traffic Disproportionate?

[Audevourahn 0]

I like the challenge of organizing the traffic in the game, however, I have to wonder if the traffic is realistic. I think that a city of 30k should never require a metro to prevent gridlock.

[RRtexasranger 45]

It is important to keep in mind that a city of 30k in the game  actually looks more like a city of 300k real life. The game has high rises which house like 20 people. That isn't realistic at all.

[BLANKBLANK 4,414]

Traffic looks about right to me. Also the population figures are vastly downplayed but still the amount of traffic produced looks right in cities of various sizes. By optimizing main road routes and strategically placing commercial, office and industrial zones around the city, one can minimize traffic considerably with barely any use whatsoever of public transport.

[iviaarten 533]

metro is a choice

 

Forkton is over 80k people right now. It has 0 metro stations, a couple of train stations for commuters, some bus lines, and a grand total of 5 main highway interchanges. I have no traffic problems.

 

I think the traffic simulation is good actually. It needs some getting used to, but after you get some main points, it's pretty good to work with.

- flow is more important than number of lanes. Space out your intersections. Traffic lights are evil. Speed is better than more lanes (I make use of highway ramps for my main distribution routes. 80 kph on a single lane, it's great.

- Make sure people want to go in different directions - don't connect to a corner or frontage road to a district. Everyone will end up wanting to make turns in the same direction. Make sure people want to go different routes, left, straight and right.

- Provide plenty of buffer room - coupled with the 'space out your intersections' thing. If you have little buffer room, a single red light, or stupidly merging cim, can clog up a lot of lanes. Make sure the room between 2 intersections is large enough to buffer all incoming traffic until the light turns green again.

- avoid placing bus stops on busy parts of roads - just moving around some bus stops and routes can really help making your traffic flow again. Avoid the really short bus bays as well. Place them somewhere where they can be long, so that it won't block a lane too often. Also, avoid putting any bus stops just before intersections (the bus will try to merge into the queue that's already waiting, causing more staggering of traffic

- use pedestrian paths and elevated pedestrian paths - pedestrians on a crossing WILL slow down traffic. Give pedestrians a way across highways, and they don't need to take their car.

- avoid zoning along your main through roads - traffic turning in and out of buildings will slow down traffic a lot. Place some pedestrian paths along these roads. It looks great, and makes sure you don't loose too much zoning space.

 

Here's some maps of Forkton

- blue is the 6 lane highway

- orange is 2 lane highway (made out of ramps)

- yellow is 4 lane avenues

- white-ish is 2 lane roads

- grey is 2 lane 1-way road

- dotted is pedestrian paths

 

 

 

Hope this helps.

[BLANKBLANK 4,414]

iviaarten, you need to make a mosaic of those road maps mate.

 

And condensing what you said, flow is the important factor to consider in CS. Optimize the flow to minimize those traffic jams.

[iviaarten 533]

teehee, I'm still looking into options to make a better map. I want it to show POI's as well Hold on, it will be great when I'm done

[perafilozof 143]

The thing is that you have way less road surface area then a real city at 30k population would have. Waaaay less. That is why it look like the traffic is bad, it's not the amount of traffic it's the amount of road space it's on.

[BlakeMW 84]

I think another serious factor is that the traffic simulator results in exceedingly dumb cims right now. For a start they compulsively drive down the middle lane on highways and 6 lane roads, they don't use turning lanes properly, they also don't use straight-through lanes properly. Often all turning and straight through traffic will pile into a single lane (say, the right lane), leaving the proper straight through lane unused. One of the most annoying things is that on 6lanes, when they queue at lights, they don't spread out over all the lanes, this massively reduces light capacity.

If cims used lanes properly, then the larger roads could easily handle 3-6x the traffic.

 

Since cims are so bad at using lanes, an argument could be made for using ramps extensively, there is very little value in having extra lanes - not no value at all, 1-way roads work well in many cases, and extra lanes can definitely help with traffic which wants to stop. The main problem is that even with traffic which wants to stop at a building, it only leaves the middle lane at the last possible moment, and when traffic enters from a building, it immediately tries to get in the middle lane, instead of entering the roadside lane and getting up to speed before merging. So the extra lanes aren't nearly as helpful as they could be.

 

Because of the severe case of mental retardation which cim drivers suffer from - not one of them should have their driver's license - the game is presently biased towards 'pedestrian' options, with Metro being by far the easiest to work with, and also being stupidly cheap compared with trains. At the moment cheap metro might even be a bit of a crutch for the failings of the traffic simulator. It would be nice if, when the traffic simulator is fixed, they increase the cost of Metro.

Note the other good pedestrian option is walkways, I build them extensively over highways and stuff and as shortcuts to bus stops/metro stations. Pedestrian walkways can get excellent usage

[iviaarten 533]

Sorry Grater, I just don't agree.

 

If all your cims stick to one lane, this shows a problem with your road design. Apparently you've set it up in a way where they all need to take the same turns. I see this a lot where people build a frontage road with all upcoming turns being right turns for instance. No wonder everyone is using the right lane.

 

The traffic AI in this game is programmed to be sort of 'model citizen drivers', they select their lane early, and don't drive like a-holes, something that is really hard to code I think . The simulation ends up showing the same problems you'd see IRL, except that IRL it would show up a couple of intersections later because of people driving like a-holes.

 

Sure, the AI can be improved upon, and some better control over turning lanes could be beneficial.

 

About the highway, and people sticking to the middle lane; do you have off ramps on both sides of your highway? Cims tend to leave the lane with incoming / outgoing ramps clear, unless they need to be in that lane for an upcoming exit they want to take. If you keep all lanes at one side, they other 2 will be used by through traffic.

[simsample 61]

Could you perhaps help me with my traffic problems? As you can see, all of the cars entering the city (coming toward us) seem to choose the same lane.

 

 

 

They take the same lane whether they are going straight on or turning left, even though the other lane is marked for going straight on too.

 

I have a six lane road where this happens, also.

 

I think maybe I need a complete redesign!

[aable 63]

Sorry Grater, I just don't agree.

 

If all your cims stick to one lane, this shows a problem with your road design. Apparently you've set it up in a way where they all need to take the same turns. I see this a lot where people build a frontage road with all upcoming turns being right turns for instance. No wonder everyone is using the right lane.

 

The traffic AI in this game is programmed to be sort of 'model citizen drivers', they select their lane early, and don't drive like a-holes, something that is really hard to code I think . The simulation ends up showing the same problems you'd see IRL, except that IRL it would show up a couple of intersections later because of people driving like a-holes.

 

Sure, the AI can be improved upon, and some better control over turning lanes could be beneficial.

 

About the highway, and people sticking to the middle lane; do you have off ramps on both sides of your highway? Cims tend to leave the lane with incoming / outgoing ramps clear, unless they need to be in that lane for an upcoming exit they want to take. If you keep all lanes at one side, they other 2 will be used by through traffic.

 

I agree 100% - The traffic simulation is not horribly broken. It's just that all the little cims are using the same GPS optimized route to get to their destinations, and if everyone's going the same way, there's no point in using 3 lanes when they would all have to merge back into one lane eventually later. Sure this isn't realistic because real life drivers don't realize this and cause other problems by driving aggressively, but if you have a mile long backup on a six lane road, it is not the simulations fault. You to provide more options for traffic to get where it wants to go and reduce obstacles (usually poorly designed intersections) that slow it down along the way.

[iviaarten 533]

Could you perhaps help me with my traffic problems? As you can see, all of the cars entering the city (coming toward us) seem to choose the same lane.

 

They take the same lane whether they are going straight on or turning left, even though the other lane is marked for going straight on too.

 

I have a six lane road where this happens, also.

 

I think maybe I need a complete redesign!

 

Like I said above; the fact that they 'can' take another lane for going straight doesn't change their lane selection. If they all want to take a left turn 2 or 3 intersections ahead, they will all preselect the left lane. Make sure that people want to go to the right as well, then they'll spread out.

 

Track some of them, see why all of them want to go left. Are all your residential zones on the left side? Are you forcing all of them into a one-way tunnel? Stuff like that.

 

edit: also, I see a LOT of delivery vans and trucks in that jam. Is that the main route between your industry and your commercial? If that's the case, you've found the source.

[simsample 61]

Like I said above; the fact that they 'can' take another lane for going straight doesn't change their lane selection. If they all want to take a left turn 2 or 3 intersections ahead, they will all preselect the left lane. Make sure that people want to go to the right as well, then they'll spread out.

 

Track some of them, see why all of them want to go left. Are all your residential zones on the left side? Are you forcing all of them into a one-way tunnel? Stuff like that.

 

edit: also, I see a LOT of delivery vans and trucks in that jam. Is that the main route between your industry and your commercial? If that's the case, you've found the source.

 

 

That road is currently the route into the city from the rest of the region (which is as yet unpopulated). The part in the pictures is the stretch of road between 'CimNation' and the industrial section (turn left) or the residential section (turn right). So I guess all of the visiting traffic is heading to the Industrial zone, being imports from outside of the city.

 

Thanks for your comments, with the information in this thread I can try to redesign the roads to make the traffic flow better.

[BLANKBLANK 4,414]

Spread out the commercial and industrial zones on both sides of main roads. Then traffic will take up more lanes and not stack up on one lane. Here's an example below-

 

 

The six-lane avenue is one of my main trunk roads in the city of Brendon, and here is the intersection with a two-lane highway which travels from west to east in Brendon, while the six-lane avenue goes from south to north. Most of the traffic in the top of the picture is heading to the CBD which is about a mile south-west from this intersection while a major industrial centre is two miles southwards. As you can see traffic doesn't hog one lane, just the lanes which constitute the quickest route to a workplace or home.

[Linoa06 1,374]

It is important to keep in mind that a city of 30k in the game  actually looks more like a city of 300k real life. The game has high rises which house like 20 people. That isn't realistic at all.

 

Unless you've already gone very high residential, a 30k city does look like a 30k city. My town of Amesbury is at 75k now and it looks smaller than an American city of 100k. I think it's a case of reality being unrealistic, heh. 

 

This is why I use very little high density buildings too. Especially the residentials.

[Mystrelia 57]

Yeah, what all these other folks are saying about the traffic using multiple lanes is also my experience. Your road infrastructure is going to be your most valuable asset in this game. I like making sure Cims can go to multiple places from all of the main roads and like to make sure I place enough main roads that they have multiple choices for getting somewhere. Overall they seem to prefer the closest route but sometimes I've been surprised to see trucks taking slightly longer routes that are less congested than what appears to be the shortest route. It's something I do when I'm driving (I mean, I can spend fifteen minutes on the freeway then another fifteen minutes getting across town to a destination or I can get on a straight road with much slower speed limits and it still takes thirty minutes to get there) and I was extremely surprised to see it in this game's traffic simulation because most people think I'm nuts for the way I drive, which is VERY much how traffic in this game is simulated. The thing is, while they're driving break-neck speed, cutting in and out of traffic and stressing out over the drive I'm kicked back and relaxing during a relatively enjoyable drive and get there in the same amount of time. Who's nuts in this situation?

[Mr_Maison 2,426]

I observed that the industrial zone is a traffic magnet. That's where all the trucks and vans are headed from out of town from the beginning of the game. It's best to make your main arteries to have plenty on and off ramp choices in and out of the industrial zone. And provide the residential with off ramps either from another highway or on the opposite side. One thing I appreciate about this game is I can still adopt my SC4 style of play when it comes to the trucks. Design the city to get them in and out as fast as possible with very minimal or no interaction with residential roads. I also keep the commercial in clusters closer to the main roads and in their own districts. I'm not finished developing my downtown yet so cannot say how that should be handled.

[Xenocity 343]

Don't forget there is a mod on Steam that allows you to edit each set of intersection and disable the traffic lights if you wish. 

This makes the bigger road have the right away.

[Mystrelia 57]

Yeah, there is just SO much going on in those industrial zones! Trucks shipping goods out, bringing goods in, then delivery trucks going out of town, down to the commercial districts, etc. I have a weird thing going on in that one part of my industry is WAY off from the rest of the city and there are cargo depots at both sections yet delivery trucks are still hauling goods that could be shipped via train over to the commercial areas. I'm sure the downfall is mine in where I placed the cargo depot but from the looks of things I'll be adding another depot in the industrial zone instead of just moving that one.

 

Right now I have buses running out to that industrial area so am still in the experimental stage of seeing how all that works. I may pull out the bus lines, add a railway and cut the roads and see what happens. Of course this COULD create all manner of chaos but that's what back-up saves are for.

[Audevourahn45 0]

Thanks for your responses everyone!  Outstanding information!  I know for a fact that some of my traffic woes are due to poor design.  It's something I'm working on!  Thanks for the tips all!

[Mystrelia 57]

Thanks for your responses everyone!  Outstanding information!  I know for a fact that some of my traffic woes are due to poor design.  It's something I'm working on!  Thanks for the tips all!

You're not alone in having problems because of a bad road lay-out. This is a brand new game with a traffic simulator different than anything a lot of us have played with. It takes a little time to figure it all out.

[BlakeMW 84]

Here are my traffic tips:

 

1) The most important thing is to have shortcuts for traffic to get to where they want to go. Don't try to stuff all the traffic between suburbs onto highways, a multitude of smaller more direct routes, works much better. It is particularly important to have shortcuts for industrial traffic.

2) As a rule, an undifferentiated city is better. As much as possible, try to mix up your residential, commercial and industrial. Low density commercial and offices make effective buffers between residential and industrial/high density commercial. Also use parks liberally for buffers. The more your workers and workplaces are mixed up, the more evenly distributed traffic will be. There are limits to how much you can do this, for example industrial really likes to be built around train stations, but you can wrap the train station with industrial, which is wrapped in commercial, which is wrapped in offices, which is wrapped in residential. This keeps the trip times short (for example goods from industrial to commercial).

3) Try to minimize intersections, especially intersections with traffic lights. Overpasses are very useful, essential really, and should especially be used to let roads pass over/under high speed lanes - don't force traffic which merely wants to get to the over side of the highway, to get on the highway, that completely defeats the purpose of the highway! Essentially when planning a high speed route, replace about 3/4 of what would be 4way intersections, with overpasses, skimping on the overpasses (in other words, replacing intersections with nothing at all), will end in gridlock as the cross traffic jams up the highway. Lack of overpasses was a mistake I constantly made until I figured it out.

4) "Ramp highways" are basically amazing, they offer most the advantages of real highways at a fraction of the cost and with more flexible splits/merges. Because they are only one lane, you get full value out of that one lane. The ideal ramp highway is ramp:2 tiles:ramp, the 2 tiles in between is wide enough for an on/off ramp to an underpassing road below. There's a bit of a learning curve to placing ramps on a grid, basically you have to use a stretch of normal road as an 'anchor' at one or both ends to get snap to grid behavior. Ramp highways should either be raised, allowing for underpasses to be used wherever you like, or regular overpasses should be built over the highway. I personally find raised ramp highways an easier choice than building overpasses.

The proper use for ramp highways are as high speed bypasses (not for bulk traffic), there should always be normal roads routes to everywhere and also highways for trunklines, the ramp highways just allow Cims to travel long distances quickly and directly, in this way they serve the purpose of removing trucks from the city streets. The traffic simulator is very good at choosing faster roads for long distance driving so an appropriately placed ramp highway bypass will attract all the truck traffic.

 

My experience is you only really need two road types : the standard road (with trees), and the ramp. Use metro to improve cim movement, and cargo station (train/ship) to improve freight movement. There are problems with highways, 4lane and 6lane which make them not as useful as they should be. They do work well enough to justify using for flavor, though.