Grid Cities impractical?

[Californiaz 33]

With the space requirement I decided to build a grid city to maximize space.

 

 

 

 

This is just constant gridlock for days on end. I dont actually think 90% moves even.

 

Needless to say my ambulances, fire trucks and police are stuck in the middle of it. City has dropped 50k in pop due to crime, fires ravage it.

 

Most are streetcar ave too. With streetcars. How can I clear them?

I have bus system, this was right after that garbage eating monster attack and me trying to recover from it.

[Californiaz 33]

oh God I did a mixed grid city.

[Jahnri 21]

Just remember having a entire network of heavy roads, will lead to more traffic. This is simply because the bigger the roads, the more traffic. Its a but counter intuitive. To actually use big roads, you need to have webs of lighter roads looped or attached to a side. Its all rather simple. Also heavy roads require mass transit.

[efgrib 45]

Just remember having a entire network of heavy roads, will lead to more traffic. This is simply because the bigger the roads, the more traffic. Its a but counter intuitive. To actually use big roads, you need to have webs of lighter roads looped or attached to a side. Its all rather simple. Also heavy roads require mass transit.

 

 

why should bigger roads alone cause more traffic? 

[SirChick 184]

Have you built buses/street cars ??? 

You might need more.

[Californiaz 33]

Just remember having a entire network of heavy roads, will lead to more traffic. This is simply because the bigger the roads, the more traffic. Its a but counter intuitive. To actually use big roads, you need to have webs of lighter roads looped or attached to a side. Its all rather simple. Also heavy roads require mass transit.

This might be it. I just upgraded every road that had traffic on it up to high

Put streetcars on the ones that wouldnt clear in the first place

 

Have you built buses/street cars ??? 

You might need more.

75% of those roads are street car high density roads with bus stops

[SirChick 184]

But how many street car vehicles do you have? Check the waiting time if its high you need more! Same applies for the buses.

 

Also wealthy people use transportation less and prefer their car.

[nhgriffith 179]

efgrib, on 05 Mar 2013 - 22:04, said:

why should bigger roads alone cause more traffic?

First of all, higher density roads means higher density buildings grow on those roads.

Second of all, all the traffic still has to run through intersections. And an intersection stops up traffic just as much no matter the density. The worst part is that that two roads of equal size get equal priority. If you connect lesser roads to major roads, the major roads get equal priority. More cars will go through a green light on the primary road then will go through a green light at the same intersection for a lesser road.

Like if a dirt road is connected to a medium density road, for example, the dirt road gets a stop sign and the medium density road has no stop at that intersection.

You can still have a grid city, but you have to put more thought into than simply running avenues all over the place.

[ethereal4k 1]

My city was gridlocked until I realized I forgot to add more streetcars. One full streetcar depot and a municipal bus station fixed everything.

[Towel 76]

You need to work out why your Grid City is impractical ... 

 

For example:

 

If the traffic is composed of mainly high wealth sims, the public transport may not help! So you need to find out their purpose.

 

Are they shoppers? Is their alternate shopping closer to their homes? High wealth sims will generate a lot of traffic if shopping is not nearby!

 

Is they're low and medium wealth sims, and they're trying to get to work or get home, then consider grouping the residential lots and focus the public transport between the residential zones and their workplaces. Let people closer by take cars or walk.

 

Make sense?

[nhgriffith 179]

By the way, your city is on fire.

[Californiaz 33]

By the way, your city is on fire.

yes thank you. All of my firetrucks reside within the jam. I built another bus depot and added more street cars but not a depot. And brought some of the roads down from high density to medium density. Helped about 25%

[shorty2 94]

By the way, your city is on fire.

[donpost 17]

I've been reading lots of posts about gridlock that cannot be dispelled no matter how you lay out the roads or how much public transport you use. It seems the engine isn't designed with cities with >100k residents in mind.

[niac123 25]

I've been reading lots of posts about gridlock that cannot be dispelled no matter how you lay out the roads or how much public transport you use. It seems the engine isn't designed with cities with >100k residents in mind.

 

 

This ^^

Think about how dense your population is. you have 100,000 people in 2 km^2. that's 50,000 people per km^2! To put that in perspective. Chicago has a population density of 11,000 people per km^2. Granted, that does include the outskirts, but you get the point.

[mastorofpuppetz 199]

The game is flawed, the tiny space means cramped unrealistic towns, that are out of proportion.

[Linoa06 1,374]

Just remember having a entire network of heavy roads, will lead to more traffic. This is simply because the bigger the roads, the more traffic. Its a but counter intuitive. To actually use big roads, you need to have webs of lighter roads looped or attached to a side. Its all rather simple. Also heavy roads require mass transit.

 

 

why should bigger roads alone cause more traffic? 

 

It's a real life effect called induced demand. That's why a highway, built to meet demands on a crowded road, will almost always become jammed itself - the highway itself generates more demand, because more people take their cars thinking the highway is faster. Both sims and real life people typically go for the fastest way on the heaviest possible axis, and therefore trigger this induced demand effect (and remember every Sim is simulated, or a ratio thereof). Of course, RL demand is much more complex than in Simcity, but since the main elements of this effect are simulated (including individual vehicles!), it is only logical that the effect is, to some extent, reproduced. In general, the demand for an expended network will almost always outdo its rise in capacity.

 

Now, if you lay all your streets very heavily, some streets will in either case emerge as BETTER heavy streets - but in Simcity it's not very well simulated so the sim thinks every of these streets is heavy, and therefore will prefer it over a slower network of streetcars, buses, etc.  In general, too, the more transit options a sim or real life person has, the more this effect is seen - this is the counter intuitive bit, when streetcars and buses are just competition to city and express streets, which might play either in your own benefit, or completely against you.  

 

I want to insist on the fact that this theorem is not simulated itself, but all of its major components are.

 

(EDIT : In a post below I've spoken about the flow of traffic, too, do read it )

 

We said that a reason for this demand to increase is that the new axis is heavier than another (for instance the streetcar system) and that In RL, many other factors would weight in, like whether you can afford a car or can properly drive on a highway; but in Simcity it's all toned down so the effect exists, but is pretty much exaggerated.

 

Another possible reason to further exacerbate this effect is a poor implementation of the traffic algorythms as a whole : cars might refuse to change lanes, or might be caught in a deadlock with the game unable to decide on an outcome when iRL drivers would implicitly or explicitly try to get out of this sticky situation, or might simply not be simulated well enough to allow for a proper resolution that would happen iRL, and that would counter-intuitively be simulated in a "lower" simulation - like the NAM - like changing routes or preferring another transit mode when jams are just too heavy. (Sometimes older simulations would simulate the induced demand effect directly, which led to more controlled effects, perhaps not as genuine though.)

[Motina 77]

Most grid cities have more than one type of road density. The highest density roads should be for moving sims from one zoning type to another, or from one node to another (like the boulevards of Paris being the best example of this). Not only this, having mentioned Paris, Paris itself is a grid city. Grids do not have to prefect rectangles or aligned properly. Go to google maps and get a good look at Rue de Rivoli, from Place de la Bastille to Place de la Concorde, with all the intersection along that street, only a hand full are high density.

[Linoa06 1,374]

I've been reading lots of posts about gridlock that cannot be dispelled no matter how you lay out the roads or how much public transport you use. It seems the engine isn't designed with cities with >100k residents in mind.

 

 

This ^^

Think about how dense your population is. you have 100,000 people in 2 km^2. that's 50,000 people per km^2! To put that in perspective. Chicago has a population density of 11,000 people per km^2. Granted, that does include the outskirts, but you get the point.

 

Yep. Paris' own density is 25k/km² which is a lot (not including the 9'000'000 inhabitant suburban city), and yet traffic there is terrible (and even more terrible now that major Delanoe decided to close the inner city expressways and change them in pedestrian walkways). Also, Paris is not a grid city (though it's an organized web) - a grided city is a place like Manhattan or Barcelona with a GRID in place, not a web of erratic streets.

 

I also think that a grided city needs heavier axis to control the flow of traffic, though it may result in a bottleneck or ten, so that all traffic is processed as best as it can through a few major roads instead of blocking every intersection in a chaotic arrangement - but that's just Simcity, I'm actually not very convinced myself. The major roads will control the traffic that will branch out to lower grade streets as it needs to, not as it wants to. This will likely result in an initial heavy demand onto these roads, but since there'll be less of them, and since Simcity isn't a full scale simulation, there will be less competition with public transit so demand will decrease. By defining a few heavy roads, you're reducing capacity on the primary road network, and therefore the demand decreases more (and I think Simcity exaggerates this effect just as well.) This is the opposite of this induced demand I mentionned earlier : if you reduce capacity on a network, the actual use of this network will almost always decrease more.

 

As for poorly developed traffic AI :

[Sunfighter 186]

City density + traffic AI that doesnt handle left turns well = what you see.

[snowhawk04 22]

I've been reading lots of posts about gridlock that cannot be dispelled no matter how you lay out the roads or how much public transport you use. It seems the engine isn't designed with cities with >100k residents in mind.

 

 

This ^^

Think about how dense your population is. you have 100,000 people in 2 km^2. that's 50,000 people per km^2! To put that in perspective. Chicago has a population density of 11,000 people per km^2. Granted, that does include the outskirts, but you get the point.

 

Uh, 2km x 2km is 4km² which means that it's actually 25,000 people per 1km², and increases once you adjust for the area consumed by non-residential zoning, roads, and services. Still terrible though.

[wilbursim 10]

Park those cars in a park and ride.. Up your buses.... Get trains in your city.. They carry thousands of passengers... More than one station

[UnkleS27 24]

City density + traffic AI that doesnt handle left turns well = what you see.

I feel like left turn singals at lights would clear up most of the traffic problems people are having...

 

Also, I try to limit intersections on my main roads as much as possible since it is the intersections that cause all of the issues.