|Operation and Maintenance of Water and Sewerage Systems (Ministry of Water - Tanzania - Rwegarulila Water Resources Institute, 1999, 90 p.)|
|B. Operation and Maintenance in Tanzania|
4.1. Quality of Water
· Bacterial contamination
· Algae, etc.
Turbidity of Water May come from
· Pumping station
· Pipe material (especially Cast Iron)
· Network fouling
Quality measurement Methods
· Single samples
· Continuously monitoring
Prevention of Contamination
· Always/pressure on the system (DAWASA!)
· Water pipe not close to servers or pit latrines (KIBINDU incidence)
· Avoid penetration of ground water during pipe laying/repair.
· Cover pipe ends during storage, transport to prevent infection by rain, dust, soil, animals.
· Brush pipe ends and joints
· After pipe laying/repair:
For Æ<100mm - clean pipe by flusting before putting into use
For Æ>100mm - clean pipeline by flusting, swabbing (use of pigs)
- If possible disinfect by filling with 20 mg/L active C/2 for 12-24 hours, followed by bacteriological sampling before putting pipe into use.
4.2 Quantity of Water
· Source not sufficient
· Population growth/migration
· Rapid industrial development
· Excessive leakages
· High peak factor
4.3 Administrative problems
· Quality control
· Leakage control
· Tariffs and revenue
· Crossing roads in new connection
· None Revenue Water etc.