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check that the step irons are sound and there are no missing step irons; |
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check for gas and oxygen deficiency; |
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check for odour indicating hydrogen sulphide (bad eggs) and other odours; |
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check the general internal structural condition of the manhole; |
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check the depth of sediment in the invert; |
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check that the sewer is operating satisfactory; |
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record evidence of rodent infestation; |
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check ladders and platforms; |
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check for gross infiltration in the sewer flow; and |
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check for signs of infiltration through the walls of the manhole. |
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This can all readily be done in the form of an operator filling in a preprinted form containing a checklist. |
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5.4.13
Layout of Connections |
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A large proportion of sewer maintenance problems are caused by poorly made lateral connections. This may cause structural failure of the sewer or blockage due to a protruding lateral. A detailed discussion of this subject is given elsewhere (Bakalian et al., 1994). The sewerage undertaker may allow a builder to make a connection or may elect to carry out the work himself and recharge the builder. In either case the sewerage undertaker should supervise the construction of all connections to existing sewers to ensure that it is properly carried out. Completed connections should be inspected externally prior to backfilling. |
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These recommendations were offered to the Kumasi Metropolitan Assembly, in the form of an operational manual for the Asafo Simplified Sewerage System. It is essential that the success |
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