Aha I seee. For drainage, am I able to dig to the outer rim, carve fortifications in the last blocks and drain that way? Or do I have to find a natural cavern that happens to reach the map edge? This is still my first world so I'm kind of remiss to channel into the caverns before I'm ready. Especially since I embarked on top of a bunch of metamorphic/igneous intrusive layers that contain a surplus of cobaltite and garnierite but no iron at all >.>. I did find some galena in my kitchen area, so blunt weapons won't be bad, but that also means wealth is going to be hard to control. I turned off invasions so I can get used to the interface and a feel for the less combative parts of the game though.
I settled away from any aquifers (which was hard, the world was 80%+ aquifer it seemed), a sort of foresty biome with a warm temperature. No flux stones either, but since I have very limited access to iron, the flux isn't too badly missed yet. Just melting down what I can trade for in the meantime and using lead and nickel to build most miscellaneous metal stuff like pipes for water pumps (yay lead-water). Settling by a natural river is turning out to be a really nice decision though.
I'm also concerned about filtering those eventual swimmer/building destroyers while still keeping my plumbing functional. They can swim through fortifications and wall grates when submerged, especially with flow. If in a 1-wide pipe I built a fortification, a wall grate, and then another fortification in a row, would the thickness stop them or would they just teleport to the other end?
i.e.
Top View: =-Wall, F-Fortification, G-Grate, 7-Water
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