Economic Effects of Sustainable Sanitation - SuSanA

Case Study Kampala
Landlord units: conventional UDDTs that are constructed by the landlords in the
compounds.
Public units: central UDDTs combined with collection tanks.
The urine from the various toilet facilities, listed above, is collected in jerrycans. The
jerrycans are not only used for the collection but also for the transport. They are abundantly
available in Uganda, either new or second hand (former frying oil jerrycans). Since the
emptying of the individual toilets with a tank truck is not feasible, due to bad accessibility and
high costs, the alternative is to allocate collection tanks throughout the slum area, where
people deliver the jerrycans to (probably with simple auxiliaries like a handcart). They empty
the jerrycans into the tanks and take them back for reuse. In this way the accessibility for a
tank truck as well as the optimum location for the delivery in terms of minimised distance to
the houses are taken into consideration. As already mentioned above, the collection tanks are
combined with public units, further on referred to as collection points, that are located in
areas, where high activity due to trade and commerce can be found. The collection points on
the one hand improve the sanitation situation of adjacent areas. On the other hand they create
income opportunities for the unit operators. Popular locations would for instance be markets.
The separation of human excreta and the delivery of the urine should be motivated by
incentives 57 paid at the collection points. The most feasible solution seems to be attaching a
value to each jerrycan that is delivered and a certain quality (e.g. pH value) is assured, to
prevent dilution with water. With this incentive scheme private toilet owners as well as youth
groups 58 or organised small collection enterprises can undertake the task of delivering and
thus generate income. The more someone delivers, the more income can be generated.
Private Company Level
The collection points should be contracted by the logistics company and operated and
maintained by one slum resident that is also in charge for handing out the incentives. In order
to assure a sufficient storage time and to minimise the size of the collection points in the
slums, a central storage site needs to be established. From the various collection points in the
slum the urine is delivered with tank trucks to the storage site on a daily basis. Due to
economies of scale, the biggest trucks available in Uganda having a capacity of 10 000 l were
identified being the most viable option.
Since the period for sanitising urine through storage for agricultural reuse is recommended to
be not less than one month, the storage site itself has to accommodate at least 30 storage
tanks 59 (WHO, 2006, p. 70). One tank is filled up every day and after a period of one month
the tank having been filled up first, is ready for distribution to the farmers.
57 Incentives are one way to trigger behavioural change (Mosler and Tobias, 2007).
58 There are positive experiences reported from Nairobi, where youth groups operate public toilets and solid
waste collection services (UNHABITAT, 2007a, p. 154).
59 Crestanks is the local supplier. The maximum volume of a tank is 24 000 l.
56