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<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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