Change in Water Quality Due to Storage:
The minimum water depth may be kept around 1.5 m as very shallow depth encourages weed growth and should be avoided. Storage normally provided purely to improve quality should at least be equivalent to 7-15 days of average water demand. This is sufficient to reduce pathogenic bacteria and river algae. The beneficial effect of storage on water of low quality is shown in Table.
Table: Change in Water Quality Due to Storage