40d Talk:Water flow

I tested running water wheels with sourced water from an underground river waterfall. The pressure of downstream the waterfall pushed the water up to one z-level below the river connection.

I connected a dead end water wheel room to it and the wheels sporadicaly moved one or two times and then stopped. Tried vertical and horizontal placement. No movement. Then I opened up the other side of the room and the water was "moving" through the room but the water wheels still did not work.

I suggest adding this information to the wiki entry for water flow. That water pushed up z-levels by downstream waterfall pressure does NOT behave like the sourced water described so far. Please note that these are just my tests and my experiences with version 40d11, if you have different results or further information please feel free to correct me. August 3, 2009 User:SpaceTurtle

This article needs to be checked over for accuracy, changed from the 1st person to something less "chatty", and have more links both to and from. Also maybe a category, "FAQ" or something?--Albedo 21:52, 3 August 2009 (UTC)

I just wanted to comment on the article. english is not my first language, so this isn't a finished draft for the wiki entry.

Just wanted to supply some information to be added to the entry if it somebody finds it useful. --SpaceTurtle 7:40, 4 Auguest 2009 (UTC)

I think albedo is not referring to your edits above, but to the main article :) --Höhlenschreck 20:27, 4 August 2009 (UTC)

This can not stay in the article space as is. Please redact and add in the actual facts and information

A further problem is that water flow is not an actual game feature, its an auxiliary construct
  and speculation used by players and eventually comes indeed down to "Why isn't my waterwheel
turning"
Do we need an extra article for that?

Water Flow (Why isn't my waterwheel turning?)

What is water flow? I want to be clear that this is about water flow, not about water depth. This is about whether or not water is considered to be flowing. Since the only real tool to demonstrate water flow is the waterwheel, it will naturally be mentioned periodically on this page.

The obvious answer would be moving water, but things seem more and less complicated than this in practice. A waterwheel needs flow to function, and it needs 4/7 or higher water. These are two different things. a stagnant loop of 4/7 water from a murky pond will not power a waterwheel as it is not flowing. However a dead end channel from a river or brook will. In fact twice I have tested and show that a dead end channel from a river or brook will continue to power the waterwheel after you block it off with a floodgate. Strange. Nor does distance seem to matter other than for the time it takes to fill the channel to 4/7. I went from corner to corner of the map, a nice long path on a 3x3 map, channeled directly from a river, dead end, and there at the extreme end of the dead end is a happily turning waterwheel. I blocked it off with a floodgate again and laughed. Either floodgates or sourced water seems to have a bug. Floodgates prevent water from passing, but the flow necessary to power a waterwheel seems to go straight though with a smile.

Water that is not directly from a brook or river is much more difficult to satisfy a waterwheel with. Water that is not directly connected to a river or brook has no natural flow. This can be because you used a diagonal baffle to eliminate the pressure so you can safely take the water down to your fortress, or it can be because you pumped the water in, or it can be because you took the water from a murky pool, or it can even be simply because you drew the short straw and got a river or brook that isn't considered to be flowing.

whatever the reason, your water doesn't have any natural flow. Generating flow with a screw pump to satisfy a water wheel is a lot more picky. Here if all three tiles under the waterwheel are the same level i.e. 4/7 then chances are your waterwheel just stopped. On the other hand it does not seem to matter if one of those three tiles is 0/7 as long as at least one of the tiles under it are 4/7 or higher. It can be very tricky to get a waterwheel to reliably turn with water that doesn't come straight from a flowing river.

Multiple waterwheels hooked up together will turn together, even if some of them do not have flow. Which is to say they will look like they are turning, but if one is not getting flow, you don't get the power for it. If they are all hooked up together with gears and axles they will all turn together as long as any one of the wheels finds flow. While this wastes 10 power for every extra wheel you use in this manner, it can be a real useful problem solving trick for keeping your underground machinery working reliably. I personally find it ironic, since an active water pump pushed water around much faster than any river, but since the water is not sourced flow is assumed to be zero unless there is an obvious difference in the water levels.

• Sourced water (river, brook, spring) behaves differently than unsourced water for powering a waterwheel.
• Dead ends don't seem to be a problem with water flow from sourced water.
• Floodgates do not seem to stop flow from sourced water. Bug?
• Unsourced water is more difficult to show flow in. More testing needed.

I'm back around, and I still have a lot more questions than answers when it comes to water. There is a bit more information in the wiki than when last I looked though. I need to figure out how to post up videos to demonstrate my tests as I do them. Doctorzuber 22:07, 17 March 2010 (UTC)

Channeling moving water

Creating water flow seems to be (semi-)reliably created where a channel is dug from a brook or river, back to the same brook or river with no diagonal connections. For example #1 will create flow, while #2 will not and #3 may or may not.

    ≈  River or Brook
    ~  Channel 
#1     
     ≈~~~    
     ≈  ~  Flow
     ≈  ~
     ≈~~~

#2
     ≈~~~
     ≈   ~ No flow (due to diagonals)
     ≈   ~
     ≈~~~

#3
     ≈~~~
     ≈  ~~~ Possible flow (not perfectly understood)
     ≈  ~~~
     ≈~~~

This is simply incorrect. Water from a natural source certainly can retain it's flow through diagonal steps. I've ran two tests to confirm this. If someone can point me to a place I can post videos, I have one of these tests saved and would like to post it so others can see. Doctorzuber 17:05, 18 March 2010 (UTC)

As for wild theorizing, if you're using diagonal steps on a river, odds are you're also dropping that river one or more z-levels. and I have certainly observed some weirdness with flow and z-level changes. My theory on this matter is the observation that only the top level or a river actually flows, if you channel it down several levels, the lower levels do not flow. So if you're dropping a river one or more levels and pulling it through diagonals to prevent pressure, you're also not going to have flow because only the top level of the river was ever actually flowing to begin with. However I do need to run more tests on this subject before saying anything for certain since I have observed other weirdness with z-level changes in water including once case where for some inexplicable reason water was flowing on the bottom level of my cistern which was quite perplexing since nothing here was actually moving, no pumps were running, the bottom level had three full levels of water above it, so nothing could possibly be moving, and yet it showed flow. Water in DF does wonky things. Doctorzuber 17:12, 18 March 2010 (UTC)

CPU usage

Maximizing framerate says "Magma and (to a lesser extent) running water are CPU hogs". Should that be mentioned here? --HebaruSan 00:24, 8 November 2009 (UTC)