ABSTRACT
Only diversion from large storage reservoirs formed by dams and from low flows in mountain streams may be free of sediment for practical purposes. Generally, some sediment will be diverted with water, regardless how well a diversion is designed and operated, and some removal of sediment from diverted water is necessary. The first requirement is that the sediment content of the water diverted must be less than the sediment transport capacity of the diverted water in its canal or conduit. If not, severe silting may result, as in the Rice Canal from Sukkur barrage on Indus river. At places over 3 m of sediment were deposited before remedial works at the inlet were carried out. The clearing process interrupts the water supply, unless several tanks are used and the others can supply water when one is emptied. The continuously operating systems use a certain fraction of the flow to flush the sediment continuously.
