Badwater as production byproduct

It may suit the theme of the Iron Teeth (or maybe some other future faction) to have more efficient versions of industrial buildings which accept water in the same way as a waterwheel, but discharge badwater. While this would, at first, be a downside smart players could game the system to make use of the badwater discharge.

Some examples: a cooled engine. As water flows past this engine (which is otherwise a wood-burning engine, like Iron Teeth already have) it allows it to work harder and produce more HP. However, water flowing out is contaminated. A similar idea could be applied to any other industrial building, like the sawmills, smelter (especially the smelter, actually), and wood workshop.