Storage Facilities for Water

All incoming waters are generally received in raw water tanks. These shall have partitions with drain valves and cleaning manholes. It is then possible to clean the sections one by one without disturbing the plant operations. 

All tanks shall have level indicators, which are clearly visible from a distance, and low-level alarms. The overflow nozzles/Unes from the tanks shall be connected to a header (which is then connected to another collection tank) so that no water is wasted at any time (water meters, flow indicators, and quantity totalisers shall also be provided to measiu e the quantities received into and consumed from important tanks). 

All important water tanks shall be calibrated and have drain valves as well as cleaning manholes to enable thorough cleaning from inside (which should be done at least once a year). The lower exit nozzles shall be a little above the drain valves so that settled matter will not go out with the treated water and will remain at bottom. It can then be drained out when the tanks are cleaned from bottom manholes. 

If possible, the lower portion of the tanks shall have conical shape for easy settling and removal of settled matter. This may, however, make a small volume of water below the exit nozzle unavailable for use (being a dead volume). 

The water tanks in the process plant shall be designated as raw water and treated water tanks (filtered water, soft water, demineralised water, boiler feed water, dilution water, etc.). 

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