|Operation and Maintenance of Water and Sewerage Systems (Ministry of Water - Tanzania - Rwegarulila Water Resources Institute, 1999, 90 p.)|
|A. Maintenance of Water Supply Units Principles and General Procedures|
A water supply system is designed and constructed for the purpose of providing an uninterrupted supply of adequate and safe water.
Proper design and construction will ensure that the unit or system will function as intended provided it is operated and maintained properly.
After the construction is completed the system is handed over to people who are responsible for running it. Their work includes operation and maintenance which attempts to ensure that the various components of the system do function as intended and render the desired service.
Operation refers to the performance of activities and use of resources for making a structure, a machine, an equipment, or a system of production do the work it is intended to do. To operate satisfactorily the system and its parts must be in a condition to do their intended work when given the necessary complementary inputs of labour, energy and raw materials.
All types of structures, machinery, or equipment, units, or system of production tend not to do the work that they are intended to do; or not to function at all, unless special efforts are made to maintain them and restore their capacity.
Maintenance mean making periodic inspections which are necessary to determine the extent of this negative tendency, carrying out appropriate remedial measure, and keeping records of the observed deficiencies and the works carried out.
The word maintenance is normally used to describe one of two distinct types of activities: preventive maintenance. The other type is corrective (curative) maintenance.
Preventive maintenance is that which is conducted to minimise malfunctioning, failures or breakdowns; corrective maintenance is that which is carried out after the damage or break down has occurred. A preventive maintenance programme cannot hope to prevent all failures or breakdowns, thus some corrective maintenance will have to be carried out from time to time. A successful preventive maintenance programme will result in less frequent failures and shorter interruptions of service.
The discussion on preventive maintenance in this Module concerns itself with the technical aspects of water supply units.
2.3 Curative Maintenance
Cases of emergency are examples of curative (corrective) maintenance and have to be dealt with as they occur.
The main cause of breakdown or malfunctioning of the unit may or may not be obvious at once. In any case the most obvious measures shall have to be taken immediately followed by systematic inspections in order to make a reliable job. At such inspections representatives of authorities who are concerned with the safety and stability of the structure, the operation of the units, and the quality of the water, should be present if possible.