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| Table 5.1 Design features of the Asafo simplified sewerage scheme |
| | Design feature | Conventional sewerage | Asafo simplified sewerage | | Change of slope | Manhole | Inspection box | | Change of diameter | Manhole | Inspection box | | Pipe junction | Manhole | Inspection box | | Connection | Upstream inspection chamber | Upstream rodding eye | | 45°90° bend | Manhole | Inspection box |
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1.0 m below trafficked areas. As none of the sewer lines passed under heavily trafficked streets, this depth of cover was sufficient in conjunction with PVC pipes. PVC pipes offer the advantage of longer lengths, and so fewer joints and thus less opportunity for poorly made joints to initiate blockages. Plastic gasket joints were used with the PVC pipes. |
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Economic circumstances has prevented the great majority of households from purchasing an appropriate WC for connection to the sewerage system. A community education campaign has been recently carried out which emphasizes the benefits to public health, the householders and the nightsoil labourers that may be achieved once the transition is made from pan latrines to the simplified sewerage system. |
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5.4
Proposed Operational Practices |
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A new manual of operational and maintenance practices was developed for the new simplified sewerage scheme. This was widely based on the Water and Sanitation Agency (WSA)/Foundation for Water Research (FWR) (1991) publication A Guide to Sewerage Operational Practices, and due acknowledgement is made to WSA and FWR, although it was adapted specifically for Ghana, and also for developing countries in general. This section discusses some of the most important issues which the manual addresses. |
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5.4.1
Ethos of Proposed Operational Practices |
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In order to develop an effective sewerage operational policy for a sewerage system it is necessary to have a clear understanding of |
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