Water Resources

Reservoir Sedimentation

Reservoirs lose their storage capacity due to sedimentation. Periodic assessment of sedimentation rates is essential to ascertain the current reservoir live storage capacity for efficient and productive management of water resources. Conventionally, assessment of sediment deposition in the reservoir is carried out either by inflow-outflow measurement method or by hydrographic survey. Hydrographic survey method is in practice for quite long time in India and elsewhere which is time consuming and costly.

Multi-temporal satellite data have been used as an aid to capacity survey of many reservoirs in a cost and time effective manner in India. While this technique helps in revising capacity table between minimum and maximum draw down level observed in satellite data, loss of dead storage capacity can be obtained only through conventional hydrographic surveys. Reservoir sedimentation surveys of 124 reservoirs of National Action Plan were executed by NRSC /DOS/Others. Similar techniques are being utilized by several State / Central Departments.