dam placement

[Don Costro]

https://steamcommunity.com/sharedfiles/filedetails/?id=2229243401
So there's 2 different rivers with flood plains in this city, I have placed one dam on the river to the right, but i cannot build the 2nd dam for the other river. Is this because the hex with dam already has both rivers on 2 sides so the dam works for both rivers?

[Lemurian1972]

The mouseover for a tile will tell you which river it is attached to. A single dam cannot apply to two rivers. I can't tell which tile you're trying to place the second dam on, but it's possible you're not allowed to put 2 dams next to each other, though I can't be positive on that without checking.

[tempest.of.emptiness]

The dam is definitely not applying to both rivers, because dams can't do that.

I believe that it is possible to place two dams adjacent to one another, although the cases where that is possible are fairly rare.

Rarely, a floodplain will spawn that ends up not having any tiles in it that can support a dam. This might be one of those cases. If the dam in your screenshot does apply to the left river, then unless the right river's floodplain includes the wheat tile that your worker is on there doesn't appear to be anywhere for a dam on the right river. If the wheat tile is on a floodplain then perhaps it is a valid dam location.

Note that if a single city builds multiple dams it can still only build one hydroelectric plant, so you may want to consider having a different city build the second dam, if you can, so that each one can benefit from its own source of clean power.

[Don Costro]

Originally posted by Lemurian1972:

The mouseover for a tile will tell you which river it is attached to. A single dam cannot apply to two rivers. I can't tell which tile you're trying to place the second dam on, but it's possible you're not allowed to put 2 dams next to each other, though I can't be positive on that without checking.

Like I said the dam is on the river to the right, which is indicated by the dam visual as well as the name of the river when i hover mouse over the hex with it. I wanted to place 2nd dam between the 1st one and tile with cattle, but i can't place it there, or anywhere else on that river. IIRC it should be possible to build 2 dams next to each other, which I did in other game.

[tempest.of.emptiness]

I just came across a situation where it made sense to build two dams adjacent to each other. I tried it and was able to do so, so I thought I would link the screenshots here to demonstrate that it is possible in the right circumstances:

Adjacent Dams (Part 1)
Adjacent Dams (Part 2)

[Don Costro]

I knew it was possible, but I still don't understand why it wasn't in that case. I was done with this game in like 70-80 turns since I put this dam there, but didn't have a flood on any of those 2 rivers, so still can't determine wheter it worked for both or not.

[tempest.of.emptiness]

The only way that one dam was protecting all of those floodplains tiles would be if there was a map generation bug. For example, some of those floodplain tiles might not have been associated with a specific floodplain (and so not able to flood or accept a dam at all), or all of the floodplain tiles might have been considered a single floodplain even though they are not all adjacent to a single river.

If the map was generated correctly, and those are two adjacent floodplains (two adjacent sets of floodplains tiles, each associated with a different river) then they would each be able to accept a dam, even if it was the same city building the dams and even if the dams were going to be adjacent. Also, a dam on one floodplain would not protect from floods on the other floodplain.

Since you were not able to build two dams, I assume that something atypical was preventing the construction of a second one. That could be a map generation issue (or a faulty map editor map), a mod or mod-related bug, or some other problem that hasn't occurred to me. Without access to the saved game itself it is hard to identify the cause. If you care to pursue this further then you could create a thread on CivFanatics[forums.civfanatics.com] and upload a copy of your saved game. Someone there may be able to figure out the cause.

[gimmethegepgun]

Originally posted by Don Costro:

I knew it was possible, but I still don't understand why it wasn't in that case.

Most likely, the floodplain the dam is on belongs to the river on the left, so the left river is dammed (despite the graphic depicting it damming the river on the right). The right river doesn't have any valid location to place a dam in range of that city (assuming that wheat tile isn't a floodplain). The rice tile the city state owns might belong to that river and should be a valid location.

[Don Costro]

Originally posted by gimmethegepgun:

Originally posted by Don Costro:

I knew it was possible, but I still don't understand why it wasn't in that case.

Most likely, the floodplain the dam is on belongs to the river on the left, so the left river is dammed (despite the graphic depicting it damming the river on the right). The right river doesn't have any valid location to place a dam in range of that city (assuming that wheat tile isn't a floodplain). The rice tile the city state owns might belong to that river and should be a valid location.

The tile with the wheat is indeed a floodplain, so as you can see there are valid tiles present for a dam on both rivers. Guess it's some kinf of a bug.

Originally posted by tempest.of.emptiness:

The only way that one dam was protecting all of those floodplains tiles would be if there was a map generation bug. For example, some of those floodplain tiles might not have been associated with a specific floodplain (and so not able to flood or accept a dam at all), or all of the floodplain tiles might have been considered a single floodplain even though they are not all adjacent to a single river.

If the map was generated correctly, and those are two adjacent floodplains (two adjacent sets of floodplains tiles, each associated with a different river) then they would each be able to accept a dam, even if it was the same city building the dams and even if the dams were going to be adjacent. Also, a dam on one floodplain would not protect from floods on the other floodplain.

Since you were not able to build two dams, I assume that something atypical was preventing the construction of a second one. That could be a map generation issue (or a faulty map editor map), a mod or mod-related bug, or some other problem that hasn't occurred to me. Without access to the saved game itself it is hard to identify the cause. If you care to pursue this further then you could create a thread on CivFanatics[forums.civfanatics.com] and upload a copy of your saved game. Someone there may be able to figure out the cause.

I have the savefile so might as well try that when I have time. Cheers

[gimmethegepgun]

Originally posted by Don Costro:

Originally posted by gimmethegepgun:

Most likely, the floodplain the dam is on belongs to the river on the left, so the left river is dammed (despite the graphic depicting it damming the river on the right). The right river doesn't have any valid location to place a dam in range of that city (assuming that wheat tile isn't a floodplain). The rice tile the city state owns might belong to that river and should be a valid location.

The tile with the wheat is indeed a floodplain, so as you can see there are valid tiles present for a dam on both rivers. Guess it's some kinf of a bug.

The one the builder is standing on?

[Don Costro]

Originally posted by gimmethegepgun:

Originally posted by Don Costro:

The tile with the wheat is indeed a floodplain, so as you can see there are valid tiles present for a dam on both rivers. Guess it's some kinf of a bug.

The one the builder is standing on?

Yes.

Also I already know what is up, I decided to play a little bit more on this file just shift + entering through turns, had floods on both rivers, and it turns out that this dam indeed works for both rivers.