Update from [~GoldenHelmet] Dec. 2, 2021
This report is used as the parent for naturally generated water flows arranged in ways that it is impossible to recreate by placing water yourself. In some of these cases flowing water generates without being connected to any source water at all.
The original description below includes several other issues that may or may not be bugs.
Steps to Reproduce:
Load up a new world in creative and enter this seed: 618588028
Go into spectator mode
Go to these coordinates: -562 -50 1083 (Corresponds with picture #2)
Go to these coordinates: -488 -38 1009 (Corresponds with picture #3)
Go to these coordinates: -714 -18 1258 (Corresponds with picture #4)
Observed Results:
Notice how in all the different places the water generates weirdly.
Expected Results:
The water should generate correctly, flow correctly, and should not be floating.
Original description:
Water mechanics are as bad as pre1.10. When u place a source block of water it only goes in one random direction. Sometimes two, but never behaves in a predictable manner. Doesnt always spread, doesnt always go the correct distance. And MOST ANNOYING! Water-flow ,with a source block connected to it 20blocks away, can still stay filled or flowing when a close source block is removed. So u can remove the one original source block and the flowing water will not dissipate if "ANY" water block is connected to it! Even if it is a redicoulous distance away.
Water doesnt fall and spread, it wont stop always when blocked, and its overall buggy and annoying.
Linked issues
is duplicated by 59
Attachments
Comments 34
Sorry but again will comment more when i get a chance.
steps to reproduce:
1: take bucket o water
2: click and place source water block on flat surface
3: observe
Observed results:
water will either run in only one direction: seems to prefer one direction more than others but is not consistent.
Expected results:
water source block placed: water should flow in all four directions from source (it doesnt) lava also does this occasionally. And we are not talking about it hitting an object duhh. (Sorry but we can skip the obvious moronic things u might averagely deal with) expected results: water should flow (forgot how far had to look it up) 7blocks .. but it stops short sometimes... and if multiple source blocks connect in a line if you take away one source block or many.. one source block can still keep "flowing water" over 10-15 blocks away.
For now you can see in the pic that water doesnt fill in blocks where its supposed to , goes where it wants, and doesnt "flow" as it should. Also when the videos are up you will see that water placed doesnt behave as it should and also water will "run" distances fed by source blocks far away. As in one video will show water dropping down 10ish blocks then running left 8-10blocks then proceeding down to spill correctly. Once source was removed the redicoulous leg of water dissipated. And its much worse than that sometimes but u see a instance of its running from a source block longer or misfed connections whatever.
Heres your videos
your gonna have to take it from youtube i aint gonna keep messing with this stupid redicoulous 10mb cap.

Based on your video, we were able to identify some anomalous behavior of flowing water and have forwarded a report to the developers. Apparently, the initial flow behavior of water in a newly generated chunk doesn't work quite like it ought to, and sometimes the flowing water it generates acts like water sources where it shouldn't.
Some of what you describe and your video demonstrates is working as intended:
When you place water within 4 blocks of a downward edge, it should only flow toward that edge, although it gets a bit more complicated when there are multiple such edges at the same distance. Sometimes it will split and flow in multiple directions. It depends partly on how far the path drops vertically.
Water flowing downward above a solid surface doesn't become a source block, but it behaves like one in some ways. Specifically, the 7-block flow limit gets reset and it looks for a new downward edge to flow toward.
Air or flowing water that has two horizontally adjacent water source blocks is converted into a water source block. Thus, if you have a line of adjacent source blocks and remove one in the middle, or remove the corner where two such lines meet, it will quickly be replaced by another source block. This means removing such a block has no net effect.
These behaviors are the same as in Java Edition. The intent is to simulate the way natural water seeks to the lowest point, but a perfect simulation is impossible in Minecraft. One reason is that MC does not simulate erosion, since eroding whole blocks would create very unnatural looking terrain. In nature, erosion stabilizes water flow in a particular direction and makes the simultaneous spread of falling water in all directions a rare phenomenon. Minecraft's rules are meant to reproduce how water flows are found in nature, not simulate how physics would shape water flows in a world where everything is made of 1-meter cubes.
still in 1.18.0

This is also apparent in 1.19.2 and 1.19.20.20

Update to this issue:
Steps to Reproduce:
Load up a new world in creative and enter this seed: 618588028
Go into spectator mode
Go to these coordinates: -648, -40, 1244 (Corresponds with picture #1)
Go to these coordinates: -562, -50, 1083 (Corresponds with picture #2)
Go to these coordinates: -488, -38, 1009 (Corresponds with picture #3)
Go to these coordinates: -714, -18, 1258 (Corresponds with picture #4)
Observed Results:
Notice how in all the different places the water generates weirdly.
Expected Results:
The water should generate correctly, flow correctly, and should not be floating.
The water shown in picture #1 no longer generates in this form. The remaining screenshots correspond to the generation of version 1.21.30.22
Still in 1.21.43
Thank you for your report!
However, this issue has been temporarily closed as Awaiting Response
Please include more information including steps to reproduce the problem:
If your ticket does not look like the example given here, then it's likely to be closed as incomplete.
This ticket will automatically reopen when you reply.
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