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Water Switch 3-in 1-out

The goal here was to work more as a switch than a pump, so it wouldn't feel like cheating... :)
For zero-power pumps there's already a mod available which should solve your scenario:
https://steamproxy.net/sharedfiles/filedetails/?id=2799112219

I don’t know the principle, but, I guess, can you make it a zero-power water pump? I think we can avoid pressure decrease in this way. But that’s just a guess indeed, I should say.

Yes, but it lowers the water pressure too much. I tested it. If I have to connect a pump downstream, it will be costly. What’s more, the water pressure can’t always come back to original level. For example, a water tower from a mod can boost the water pressure to 5 bar, but when I connect it to the 2-in 2-out switch and then to a large booster pump station, the pressure eventually drop from 5 bar to 3 bar. You know how serious it affects my city’s water supply.

It's like it says in the description: "It decreases the wafer flow a bit if not followed by a pump downstream (couldn't find a way around this limitation in the game) - see screenshot"
You need to add a pump after the output

Besides, it happens on 2-in 2-out switches.

I should report a serious bug:

Whenever I use your switch, the water pressure immediately drops from 5.30 bar (input) to approximately 0.30 bar (output), and the maximum water flow seriously plummets, from over 250 m³/s to 4 m³/s.

Please fix it ASAP, otherwise I have to choose between citizens' death (it has caused 2,740) and a switch that can make water converges. Now I have to use a pump every time I want water to converge.

“Update 16 Oct 2022: Added on/off switches, and 1-in 1-out version.”
Really? Then you should add it to the title, rather than remain the original title.

Once I've noticed flow reduction on vanilla switch too.

@roxik0
Thanks for reporting this. I tested the scenario and unfortunately you are right - these switches will reduce the water flow if not followed by a water pump downstream.
I couldn't find a way to do this in the game without turning it into a real pump (which would defeat the purpose)...

I realize this limits that usefulness of this mod, as you can get the same result by using just the vanilla 3-in 3-out pump... But I thinks this can still be useful when using lower flow pipes and the small vanilla 1-1 water pump.

I added a screenshot and updated the description to reflect this.

@des
I found bug in your mod:
Connect in order:
1) water well => water pump => underground storage result flow about 27 m3/s
2) water well => water pump => vanillia switch => wanillia switch => storage : result flow 27 m3/s
3) water well => water pump => your switch => your switch =>storage: result flow 0.3 m3/s

Generally even if you put one of your switches it limits max flow..