Reuse of faeces and urine from ecological sanitation
Practical Action
Application of Urine
Urine can be dealt with in a number of ways. As mentioned above, direct use should only be
practiced on a household level, on a larger scale one should practice storage and re-use. In
some ecosan toilets the urine will automatically go to a selected soil bed for soaking or to
fertilise a small group of plants (e.g. the Kerala double vault dehydration toilet). The various
options are shown in figure 2.
The following are practical recommendations when utilising urine from ecosan facilities
(WHO, 2006; Schönning and Stenström, 2004; EcoSanRes, n.d:a; EcoSanRes, n.d:b; Slob,
2005):
urine should ideally be worked into the soil, this could be achieved via mechanical
means or it could be subsequently watered into the soil i.e. with irrigation water (as
mentioned urine should ideally not be stored diluted);
the urine should be applied close to the ground to minimise aerosol formation, this
could be done manually or, on a larger scale, with agricultural equipment;
if Schistosoma haematobium is endemic in a region the urine must not be used near
freshwater sources;
a general rule of thumb is that the urine from one person in 24 hours can be applied
to 1m2 of land per growing season (guidelines based on local fertiliser requirements
can be found from EcoSanRes (n.d:b));
use of urine should stop between approximately 2/3 and 3/4 of the time between
sowing and harvest, after this time the plants reach their reproductive stage and take
up less nutrients; and
if the urine is likely to have suffered cross contamination further precautions such as
protective clothing should be worn. Hand washing should always be practiced.
Alternative use for urine
If the use of urine is not culturally acceptable in food production, the urine can also be added
to compost piles to assist the decomposition process. As mentioned the urine can also be
soaked away, evaporated or discharge to a plant box connected directly to the toilet.
Mixed faeces and urine
In some forms of ecosan urine diversion does not take place and the faeces are mixed with
the urine. In this case the waste is treated in the
same way as faeces. The most established
ecosan systems using this method are the Fossa
Alterna and the Aborloo. If removed from the pit
the resulting compost is similar to that from just
faeces, carrying no offensive smell and
resembling soil (figure 3).
Figure 3: Inspecting mixed compost.
[Source: Morgan, 2007]
useful aspects of both components.
Pathogens
The pathogens in the material will be the same
as faeces, the difference will be that many useful
nutrients contained within the urine may be lost
in the process. Assuming enough educational
support and cultural acceptance urine diversion
should ideally be used, as this utilises the most
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