So i made a well...

[BetrayalAtK]

With materials averaging on 25q and on the center of the source where the tooltip "quality will not rise higher" or something like that appears.

Water quality is 10.... did i do something wrong or is just bad luck i dug up the worst underground river ever.

[boreial]

Quality of materials in this case do not matter, water quality is node based. In your case, you're not close to a node of any other than base quality.

[BetrayalAtK]

Dammit