[Hegemony Cricket]

"clay-laced water"???????????????

Uh, with all due respect, what in the world does that phrase mean? From what little I know about pottery making, "clay-laced water" seems a bit odd. I know that you mix water and clay until it's moldable, but that would (I think) be way too thick to flow through "an elaborate water system". Additionally, "clay-laced water" (again, I think) would tend to gum up the works after a short time. Altogether this explanation does not pass the sniff test with me...

[GoLightly]

A clay sluice is used in the kind of pottery making where a mold is used. The mold is made of a porous material & it draws the water out of the sluice that is closest to it. After a certain clay thickness builds up by the mold, excess sluice gets poured out & the molded artifact left is dried further. It's a way to do production with fewer craftsmen, than the pot making done with firmer clay.

An open waterworks would be a way to deal with a sluice gummin up the works.