|
|
|
|
|
|
|
that the work is carried out safely by suitably trained and supervised operatives following accepted safe working practices. |
|
|
|
|
|
|
|
|
It is extremely important that where there are mains water supplies to sewerage installations, they should only be connected by pumping from a storage tank. Local laws should reinforce this action to prevent any possible contamination to the public water supply. |
|
|
|
|
|
|
|
|
5.4.7
Operational Problems |
|
|
|
|
|
|
|
|
Sewer cleaning and blockage clearance work will typically involve a mixture of reactive and planned maintenance work. Reactive maintenance will be needed to clear blockages of debris which may be causing localized flooding or restrictions on toilet use. Where there are persistent problems, it may be appropriate to carry out sewer cleaning of some lengths of pipe on a planned maintenance basis. It may also be necessary to clean out some flow control devices such as those on storm overflows, grit collection chambers and detention tanks after operation of the installations. The following procedures are recommended for sewer cleaning work. |
|
|
|
|
|
|
|
|
1. Steps should be taken to prevent sediment and debris from entering the sewer system. This can be achieved by ensuring that builders take appropriate action during the construction works. Careful thought should also be given to the design of inspection chambers and manholes, to prevent the possibility of sand and dust entering the system through these appurtenances. |
|
|
|
|
|
|
|
|
2. Where sediment problems have occurred and recurrence is considered a possibility, periodic inspections should be carried out to determine current sediment depths and the rate of deposition. Where the problem recurs, planned maintenance should be considered. |
|
|
|
|
|
|
|
|
3. The sewerage manager will need to have procedures for |
|
|
|
|
|