Technical Guide to EcoSan Promotion

3.1 Introduction
A Urine Diverting Dehydrating Toilet (UDDT) is a toilet that operates without
water and has a divider that enables the user to divert the urine away from the
faeces with little effort (Tilley Elizabeth et al, 2008). The origin of UDDT is the
conclusion of efforts by environmentalists,NGOs and donors to produce a toilet that
not only meets personal sanitation needs, but also overcomes the challenges of local
conditions without negative environmental impacts. The UDDT was invented in
Africa in the 1990s.
Some users find difficulty in immediately comprehending what a UDDT entails.
In their first encounter with this gadget, such users may hesitate to use it. This is
exacerbated when mistakes such as dropping of faeces in the urine bowl may deter
them from accepting this type of toilet. This therefore justifies the need for education
and demonstration projects essential to boost user acceptance.
Fertiliser produced by a UDDT is sufficient to recover the cost of building it. This
has been a greater incentive for buying into the idea than hygiene or convenience. In
western Kenya, the driving force for converting to Ecosan is the benefits it brings to
agriculture. The cost of building a UDDT starts from US$ 307(Ksh.23,000), with
the cheapest model derived from the use of iron sheets instead of cement blocks or
earth bricks.
The UDDTs are appropriate for almost every climate (Tilley, 2008). Hygienisation
in the faeces chamber is realized through heating of up to 50 degrees Celsius and
high pH value from the addition of alkaline material. This way, the moisture content
is reduced to about 25%. UDDTs are particularly suitable for areas with the following
characteristics: Low sanitation access and coverage; Unstable, shifting soils; A high
incidence of waterborne disease, especially routine cholera outbreaks; High water
tables and seasonal flooding; and Low agricultural yields caused by depleted soils.
3.2 Systems Description of a UDDT
3.2.1 Definition and how a UDDT works
A Urine Diversion Dehydrating Toilet is basically a collection system where human
urine is separated at the source before it mixes with faeces using specially designed
toilets and urinals, piping systems and storage containers. The UDDT is built such
that urine is collected and drained from the front area of the toilet, while faeces
fall through a large chute in the back(for details see annex 1 ). Depending on the
collection and storage/treatment technology that follows, drying material such as
lime, ash or earth should be added into the same hole after defecation.
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