Assessment of reservoir sedimentation using remote sensing

Efficient management of a reservoir calls for periodic assessment of its capacity. Hydrographic surveys of reservoirs provide valuable information on the rate and pattern of sedimentation, which is required for formulating measures to control sediment inflow and for optimum reservoir operation. Data from space platforms can play a significant role in reservoir capacity surveys. In the recent past, satellite remote sensing has emerged as an important tool in rapid, frequent and economical reservoir sedimentation assessment. Multi-temporal satellite data help in determining water surface areas for different water levels. Any reduction in the reservoir surface area at a specified water level over a time period is indicative of sediment deposition at and below that level. When integrated over a range of water levels, it permits the loss of storage due to sedimentation to be computed. Remote sensing techniques have been used to assess sedimentation rates in a number of reservoirs and the results are described in the paper.