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together with water supply and sanitation engineers, must continue to develop programmes that improve urban, especially peri-urban, health. Low-cost sewerage has a vital role in this area of global public health. |
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2.2
On-Site or Off-Site Sanitation? |
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The research and development done by the World Bank during 197686 (see Kalbermatten et al., 1982a,b; Feachem et al., 1983) has clearly shown that possession and proper use and maintenance of a sanitation facility is more important, in terms of improving health, than the actual sanitation technology employed, provided of course that it is affordable and socioculturally acceptable. None the less, sanitation technology choices have to be made, and the principal choice is between onsite and off-site systems. These are the following: |
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VIP latrines
Pour-flush toilets
Septic tanks |
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Conventional sewerage
Unconventional sewerage
settled sewerage
simplified sewerage |
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These are adequately described in the literaturesee, for example, Mara (1984, 1985), Mara and Sinnatamby (1986), Otis and Mara (1985), Sinnatamby (1986), Bakalian et al. (1994) and, more generally, Mara (1996). On-site systems can be upgraded over time, and with corresponding improvements in water supply, to settled sewerage systems (see Kalbermatten et al., 1982b; Mara, 1996). |
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2.2.1
Nomenclature of Unconventional Sewerage |
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At present this is confusing: both the unconventional sewerage technologies listed above use small diameter sewers laid at shallow depths and in which the flow is, wherever possible, by |
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