Three years of operation of the urine diversion system at GTZ headquarters in Germany: user opinions and maintenance challenges.

In the main office building of GTZ in Eschborn, Germany a resource-oriented sanitation system containing urine diversion (UD) toilets and waterless urinals has been in operation since 2006. After 2.5 years of operating the system, a first overall evaluation of the system in terms of its acceptance amongst the users and the cleaning staff was conducted by carrying out two surveys and many interviews. The overall result is that most of the users appreciate the sanitation concept in theory but have problems with the technical design of the particular type of UD flush toilets installed here. The survey results also gave some directions towards which hygiene devices the users would appreciate in order to overcome their reluctance to sit down on the toilet seat in public buildings (the sitting being necessary for correct operation of the urine valve to separate urine from flush water). Also, it is difficult to convince the cleaning and facility maintenance staff of the necessity of special cleaning and preventative maintenance routines. Hence, before such systems can be widely used, clear cleaning routines and maintenance instruction are required as well as certain technical modifications of this type of UD flush toilets to optimise the urine/water separation and the flushing properties of the toilet.