The toilets flush with purified grey water, cutting ordinary water usage close to half.

The sewage treatment of the Noah house is trademarked. The house treats grey water as well as sewage. The sewage treatment is done in 3 phases.

Phase one is a biological settling/dissolving pool where sewage mud gets removed.

In phase two, the sewage water leaks through a filter-bed.

As phase three, the treated sewage water gets a further sterilizing UV treatment, and some gets recycled to flush the toilets, which further minimises water consumption. The remainder gets leaked away or used to water the garden. 


The mud that’s left in the system, can be removed during the general 2 yearly manintenance (can even be used as compost).