.....
o.O
It's flooding?

??
I had a system set up to drain excess water out of my obsidian factory. The water is shunted through constructed walls to fall back into the source (a brook) via two channeled brook tiles.
This system also happened to become the saviour of my fortress, helping to prevent, then reverse flooding due to an oversight.
The only thing is this - nobody ever mentioned that pumping water into a brook in this fashion could cause un-channeled brook tiles to flood if done too quickly.
...
There's a massive area of mud and such around the channeled-out tiles, outside the containing walls. And for those who might ask, yes, I did build a ceiling above the channel via floors one z-level up.
Wow. There's nothing like a few screen-lengths of 'muddy brook' the distract a person.
Does mud go away outside, like blood and such, or is it a different type of thing?
Level 1
XXX~~~X
XXX~~~X
XXX~~~X
XXX~~~X
XXX~~~X
XXX~~~X
XXX~~~X
Level 2
BBBBBBB
WWWWWBB
~~~HWBB
~~~HWBB
WWWWWBB
BBBBBBB
BBBBBBB
Level 3
AAAAAAA
AAAAAAA
FFFFFAA
FFFFFAA
FFFFFAA
AAAAAAA
AAAAAAA
~ = water
H = channel
F = floor
X = solid ground
A = open air
B = clear ground
All of the clear ground (B) is now muddy, including the brook tiles. D: