| Removing human waste
- the Vacutug solution
By Graham Alabaster and Iole Issaias
While world andcivil society
agonise over how to meet theMillennium Development
Goal of halving the number of poeple without
access to adequate water and sanitation by
2015, interim solutions have to be found to
remove human waste safely from slums that
are home to almost 1 billion people around
the world.
According to the latest
UN-HABITAT statistics, the majority of these
1 billion people live in developing countries
where over 40 percent of the urban populations
live in slums.
The interim solutions also
help sustain the goals set as improvements
gradually come into place. Moreover any future
investments in sanitation infrastructure will
need to go hand-in-hand with investments in
adequate human waste removal from either on-site
or off-site sanitation systems, if these goals
are to be truly met and sustained in the years
to come.
|
| The UN-HABITAT Vacutug on field testing
in Kibera, Nairobi. Photo © UN-HABITAT.
|
Thus in 1996, UN-HABITAT
in association with Manus Coffey Associates,
designed a machine to provide sanitation services
for the residents of densely populated low
income settlements to remove the human waste
from pit latrines. Known as the UN-HABITAT
Vacutug, it is engineered for access to
pit latrines in the narrow, unpaved streets
of poverty stricken slum settlements where
larger removal vehicles cannot pass.
Composed of a vacuum tank
and a pump assembly with a capacity of 500
litres, it is operated by a small gasoline
engine that has the capacity to remove waste
at 1,700 liters a minute.
In 1997, the machine was
tested on the outskirts of the Kenyan capital,
Nairobi, by a local NGO in Kibera, the largest
informal settlement in East Africa, to see
whether or not its design and overall management
would be feasible. The sustainability factor
of the UN-HABITAT Vacutug was it's
potential to generate income because it is
operated by a team of five that is able to
remove human waste at a cost equivalent to
US$ 7 per load.
The pilot phase has shown
a huge demand and willingness to pay for this
service in Kibera. It also meant that for
the community there was no need to close down
pit latrines when they became full and thus
no need to relocate them, or manually empty
them.
Together with good hygiene
promotion, the machine can be fully integrated
into a sanitation system, which would altogether
be more effective in providing adequate sanitation.
Furthermore it was deemed a success in terms
of its income generating and cost recovery
potential — it earned about 36 per cent
profit on total initial cost.
But before any claims can
be made on the viability of the machine providing
adequate removal of human waste in low-income
areas, more information on the socio-cultural
and financial sustainability factors will
be required.
There are certain design
modifications which have to be made to make
the machine more durable and efficient under
the rough conditions in which it operates.
Currently there are nine
machines undergoing field trials in Africa,
Asia and Latin America under a programme funded
by the Department for International Development
(DFID) of the United Kingdom and Irish Aid.
The machines will be tested
for a year in various cities in developing
countries, under different conditions and
managerial structures: some will be tested
in informal settlements, rural areas, a refugee
camp, and by a local municipality. UN-HABITAT
will share the results via the Internet.
It is hoped after the trial period any final
design changes will be made and the machine
can then be sold commercially.
Graham Alabaster is a Human
Settlements Officer in the Water, Sanitation
and Infrastructure Branch of UN-HABITAT and
a Programme Manager of the Water for African
and Asian Cities Programmes.
Iole Issaias is a consultant
with UN-HABITAT's Water and Sanitation Branch
who also manages the vacutug project.
|
