Newsletter and Technical Publications
<International Source Book On Environmentally Sound Technologies
for Wastewater and Stormwater Management>
9.11.5 An Exercise in Appropriate Technology - Case Study of a Typical Village
in St. Lucia
The paper is titled Small Community Wastewater Treatment Systems authored by
Francine Clouden from the
Caribbean Environmental Health Institute in St. Lucia.
The village is located on the East Coast of St. Lucia. The soil type is extremely
rocky in some areas and the ground water table is high, as the main part of the
villages is located in a flood plain close to the ocean. Houses are located
very close to each other and the development is random and unplanned.
The total population of the village is
4440 (1992 census) with a total number of households of 1179.
St. Lucia Water and Sewerage Authority
(WASA) supplies the potable water, with intakes located in the vicinity.
Treatment consists of a stone filter, sand filters (in parallel), and
chlorination. 23% of the population are supplied by standpipes in the neighborhood,
50% have a private supply (i.e. piped water in the home) and 27% have none
available close by i.e. no standpipe within walking distance. Because of the
topography regularity of the supply is compromised.
Current excreta disposal practices are as
follows: 11% pit latrines; 13% pail latrines; 34% water closet and septic tank;
42% none on premises. This forty-two percent of the residents (600 persons) use
the public facilities provided of which there are five with a total of 22
toilets and 24 showers operational.
Most of the facilities were built 15 to
20 years ago and include showering and laundering facilities. All the
facilities operate with the same system. The grey water is discharged either
directly into the sea or into a surface drain that runs into the sea. Excreta
("black water" is treated in a septic tank. The effluent from the septic tank
is disposed of into a soakaway through a pipeline. A pump truck is used to
remove the sludge remaining in the septic tank. The regularity of this is dependent
on the availability of the pump truck, which is sporadic due to frequent
breakdowns.
At one of the facilities located at the
beach the use of the toilets was discontinued in order to avoid pollution
caused by a crack in the pipe of the septic tank and the proximity of the
corresponding soakaway to the sea. Bathing in the 4 shower rooms and laundry is
still practiced and the grey water goes directly into the sea.
The newest facility, built in 1994, near
the fishing port of the village is in comparatively good condition. It is
equipped with 8 toilets and 8 shower rooms. As the caretaker reported the only
problem encountered is frequent breaking of the toilets cisterns because
domestic fittings have been used.
Another facility is elevated, therefore
some problems are encountered with its water supply.
At certain times, especially in the morning the water supply
fails in the whole facility.
The remaining two facilities are working
well. Both are centrally located, where most of the houses have no private
amenities.
Moreover the two facilities at the beach
have night soil chutes to prevent the residents from throwing their night soil
into the river. Unfortunately the use of the night soil chutes had to be
discontinued due to the residents disposing of solid waste into them. This led
to frequent choking which caused the maintenance cost to rise. Additionally,
the instruction board for proper use of the chutes has gone missing from one of
the facilities.
Most of the public facilities have in
common that they are not maintained properly, have often fallen into disrepair
and are subject to vandalism by the residents.
The result of most of these problems is
that the village has a high incidence of diarrhaoel and other enteric diseases
such as Typhoid Fever and Dysentery. A recent survey (stool examinations)
revealed that 65% of the school age children in the village were infested with
some type of Helminthes. Monitoring of the potable water supply over a
two-and-a-half week period during the rainy season showed that the quality of
drinking water was quite good. The conclusion may be drawn therefore that poor
sanitation, hygiene and excreta disposal are the main causes of the high
incidence of disease.
The systems currently being used in the village are all deemed "appropriate
technology" yet they still failed. The information just presented suggests
that the problem in the village cannot be solved solely by a technical approach
such as construction of Pit Latrines or improvement in water supply. It would
be relatively simple to recommend and design such. Other short-term solutions
such as repair and rehabilitation of public facilities can also be implemented
but a more holistic approach involving all stakeholders needs to be adopted.
The previous failure of the other projects, such as the night soil chutes and
the lack of regard of residents towards the public facility need to be examined
and addressed before any solution can be successfully implemented. The practices
of the reverting to using the bushes or rivers when the water supply is bad
indicates a general lack of understanding on the part of residents of basic
sanitation and hygiene issues, and their link to the incidence of illness and
diseases.
We can therefore conclude that the term "appropriate technology"
should refer not only to the technical solution but should encompass a complete
system that addresses social, cultural and economic issues.
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