Newsletter and Technical Publications
<International Source Book On Environmentally Sound Technologies
for Wastewater and Stormwater Management>
6.2 Reuse of wastewater from on-site systems
Many options are open to a householder who wishes to reuse wastes on-site.
One option is separation of all wastes. Urine can be separately collected and
stored for later use as a liquid fertiliser, rich in nitrogen, phosphorus and
potassium. Toilet wastes can be composted and used as a soil conditioner, rich
in organic carbon, nitrogen and phosphorus. Greywater can be treated in a
constructed wetland and used for sub-surface irrigation of the garden beds
(Figure 2.44). This option may be suitable for a householder who is interested
in managing wastes for beneficial uses in the garden, being a keen gardener.
Sufficient garden area needs to be available for this purpose.
Figure 2.44: Separation of household wastewater for on-site reuse
(Lange and Otterpohl, 1997)
Another option is the use of an evapotranspiration system for
growing shrubs and trees (see Section 2 (4.1.4)). This is a passive system, not
requiring household attention on a regular basis, except desludging of the
septic tank every 3 to 5 years. There is a fairly wide choice of shrubs and
trees to choose from depending on local soil and climatic conditions.