cities-skylines
What penalties will I suffer if I upgrade a stretch of road and cause all the low density residential to be demolished? Will this create unhappiness, or will the houses just get re-built afterwards?
The problem arose due to a traffic bottleneck where my incoming highway enters my city.
Related questions
It may take some time to unlock it, but after you've passed enough milestones there will be a population info view in the info panel (top left button). It appears as a grey person pictogram, roughly halfway up on the left (5th up from the bottom as of version 1.4). This shows the current percentage that are unemployed.
Additionally, if you press Esc or click on the menu button at the top right, you can open the statistics menu where you can see your employment rate over time (after choosing the option from the tick list on the right).
The simplest, easiest and most compact way to connect the starting highway to a smaller main road is to just use a pair of one-way roads - one set from the incoming highway to the end of the main road, and one from the end of the main road to the outgoing highway.
This isn't necessarily the best junction, but it avoids traffic lights and allows uninterrupted flow of traffic on to and off of the highway - all for very little effort. I've found it to be sufficient for quite a long while after starting a city, I get much more traffic build up elsewhere first.
At the start of the game you cannot build additional highways, so for now you can use one-way 2-lane roads (see left image). This isn't great though - as well as looking a bit odd, the 2-lane road also has a lower speed limit than both the highway and six-line that it connects. It still works pretty well, but you should upgrade these links to use highway once you unlock them (see right image).
Highways at the top. 6-lane at the bottom.
2-lane version is left image. Highway version is right image.
Also, as a bonus, you can see an extra outbound highway link coming from the left for trucks leaving my industrial area.
Note how that merges with the other highway section in a way that doesn't interrupt traffic.
As said, this still isn't perfect. If you note the inbound road has a 'turn right' arrow in its right hand lane - which allows traffic to U-turn back onto the highway. In the highway version, this actually means only the left two of the three lanes will be used to merge.
Best Answer
Happiness is calculated per building, not per person. People who lose their homes are no longer considered your citizens, so their opinion is irrelevant. Throwing a few hundred families onto the street will not affect your approval rating at all (at least not directly).
The biggest penalty you get for bulldozing buildings is that you lose their current upgrade progress. The replacement buildings will start back at level 1, which means that for quite some time they will house less people than they used to. It can then take a while until they are back to the level they had.
When you demolish and reassign a considerable percentage of your residential areas at once, you might
This means that large-scale replanning of your city layout should not be done all at once but step by step with breaks in between to let the newly assigned quarters develop.