Author(s): Durga Prasad Sangroula
Linked Author(s):
Keywords: Sediment yield; Sedimentation; Sediment sampling; Concentration analysis; Bathymetric survey; And Kulekhani Reservoir
Abstract: Sediment discharge measurements in streams are quite rare even in technologically advanced countries, whilst comprehensive physically based models are generally unable to reliably estimate sediment yield of river basins. Estimates of long-term sediment yield have been used for many decades to size the sediment storage pool and estimate reservoir life. However, these estimates are often inaccurate, and many reservoirs have accumulated sediment more rapidly than originally expected. The documentation of sediment loads in Himalayan Rivers is a major problem for the researcher. Long term data are absent, peak flows are usually missed during measurement and bed loads are not measured at all. River gauging stations are rare and most of those that exist do not measure sediment loads. The Kulekhani Hydroelectric Plant, which is the only seasonal storage type of project in Nepal, suffers from serious sedimentation problems. Several studies have been made related to sedimentation processes in the Kulekhani Reservoir. These studies indicated that the sediment delivery from the Kulekhani Watershed is much higher than anticipated. In June 2003, flow gauging stations and water sampling system was established in the major streams flowing into the Kulekhani Reservoir and in November 2003, bathymetric survey of reservoir was carried out by using improved technology for recording and processing of data as a part of the field work of the PhD research by the author. This paper highlights the process of estimation of the sediment yield based on the stream flow data and sediment concentration in the major streams flowing into the reservoir, generation of bathymetric map and some general information on hydropower development in Nepal.
Year: 2004