Bas-Lag Wiki
"You'll see the dockers doing it sometimes, in Kelltree or Smog Bend. A whole gang of them can shape quite a bit of the river. They dig holes in the water down to where spilt cargoes lie on the bottom, so the cranes can hook them. Fucking amazing. In rural communities they use it to cut trenches of air through rivers, then drive fish into them. They just fly out of the flat side of the river and flop onto the ground. Brilliant. ...Anyway, these days it's mostly just used to arse about, make little sculptures. They have little competitions and whatnot."
—Isaac, speaking to Yagharek

Watercraeft, also written as watercræft, is the ability of the vodyanoi to mold water into shapes. It is considered a subset of thaumaturgy, although its principles are poorly understood by New Crobuzon academics.

Events of Perdido Street Station[]

Early on during the events of Perdido Street Station, watercraeft is used by striking Vodyanoi in order to prevent the passage of ships through the River Tar until the workers are given better wages.

Isaac Dan der Grimnebulin also sees watercraft as a useful way of studying crisis energy, and the thaumaturgy inspires him to create a crisis engine.