How do we reduce the water use in the Hack Shack?
We use a dry toilet; specifically we use an UDDT (Urine Diverting Dry Toilets).
Dry toilets don’t need water.
To eliminate odor, UDDT separate the urine from the poop and have an air vent to passively extract air from the poop chamber :). So there is no smell. Adding some appropriate bathroom illumination, you avoid unpleasant sightings in the toilet.
We build a double vault system so throughout a year each vault is in use 6 month. After 6 month of use the toilet is disabled and the accumulated shit rests for another 6 month and dehydrates, eliminating all the disease causing bacteria. The feces have decomposed to pathogen- free regular earth. Then we retrieve the bin from the vault and use the dehydrated material for soil improvement, before using the toilet vault again.
The toilet seat is in shape of a bench with a nice wooden ring. When the toilet is not in use, we cover the hole with a lid and the cubicle is used as shower cubicle.
Consider that each time we flush a regular toilet, we use 6-10 liters to transport our poop and pee through a sewer system to be treated at a centralized treatment plant that overflows with heavy rains.
With a dry toilet we save all this drinking water and we treat our excrement right in the place where we generate them, avoiding a costly infrastructure.
For more inspiring thoughts on water and poop watch this delighting ted talk from Molly Winter or for a detailed review here an outstanding and very complete technology review of Urine Diverting Dry Toilets published by the GIZ.