Lost Water

I noticed the exact same thing in my first play through. I kept draining pockets of contaminated water into my holding cistern expecting it to fill the cistern up and I'd never end up with very much water in the end. This led to an earlier-than-necessary demise for my dupes. My setup used a pump to push the water from an outside collection point, but the loss was evident before it hit the pump so I don't know that the pump was the culprit. It just seems like there is a huge water loss as it travels across cavern floors. It wasn't that hot so I don't suspect evaporation, but something is absorbing the water as it travels.

This bug report was never addressed, and others have started posting about it.  I have been testing it with both visual queues (the squares to fill up the reservoirs/cisterns), and the actual liquid value (Kgs -- you can see my other posts to get them to change that value to L).

I think we will have to keep posting about it until someone notices.