(Proceedings, INDIA HYDRO 2005, 19–21 February 2005, New Delhi, pp. 65–73).
Reliable and efficient systems for sediment control and removal of sediment from withdrawn water will always be one of several preconditions for successful use of water resources. Sediment handling technologies have been developed the past 11 years, which enable efficient suction and transport of sediment through pipelines and thus exclusion of sediment at intakes and waterways and removal of sediment deposits from reservoirs. In addition to hydropower experience, substantial experience is gained from sediment handling in connection with offshore oil and gas industry. The Slotted Pipe sediment Sluicer (SPSS), enables efficient removal of sediment from sand traps and desilting basins. Due its special design the SPSS ensures that an absolute minimum of water is used for transport of sediment. And that a very low head is required. Being able to operate without inspection for nearly four years at Khimti hydropower plant in Nepal the SPSS is also verified to be suitable for open sand traps and desilting basins. Suction heads like the Saxophone Sediment Sluicer (SSS), has made it possible to operate gravity dredging systems from the surface of deep reservoirs without monitoring or special maneuvering. Disintegration of cohesive material can be obtained with water jetting. During the summer of 2004 cohesive clay that had been dried out during the winter season was removed from a small irrigation reservoir in Ethiopia. It is concluded that newly developed technologies have proven reliable in suction and transport of different types of sediment through pipelines and that sediments can be removed from inaccessible places, such as in pressurized tunnel sand traps and in deep reservoirs.
Sediment control, Preconditions, Desilting basins, Dredging systems, Disintegration, Cohesive material, Water jetting, Newly developed technologies, Reliable, Sand traps, Deep reservoirs
