Good new everyone!
I`ve found than Lavaratory and showers intakes 10 kg of water per second at max pressure in pipe (Each bkue cirlce - 10 kg kf water). But output only 1 kg ptr second of contaminated water (Each green-yellow circle - 1000 g). So it wasted huge amounts of water. However, according to the description it must not consume water at all, just converts it to contaminated water with the same amount.
Steps to Reproduce
Build a lavaratory, a shower. Connect it to pipes with max liquid pressure. Use it. Look at liquid layer to intake and output amounts.
This issue has not been confirmed by a developer yet.