The report presents the status of the sediment studies carried out in the lower as well as higher altitude region of the Garhwal Himalayas. The processes associated with sediment production in the mountainous region have been described with an emphasis on the glaciarized region. Suspended sediment concentration and load observed in the Dokraini glacier melt stream near its snout has been computed.
The estimation of sediment load from the glaciarized basins is very important for planning, designing, installation and operation of hydro-power projects including management of reservoirs.
Sediment yield from the Dokriani glacier is found to be very high as compared to other Himalayan basins. Sediment yield for the melt period is computed to be about 2800 t/sqkm yr, which is comparable to glaciarized basins in Pamir region.
The erosion for Dokriani glacier basin is estimated to be about 2 mm for the ablation period, which is higher than the erosion rate reported by other investigators for the glaciarized basins in Europe.
Attempts have been made to correlate sediment concentration and load with glacier melt runoff. A poor relationship is found between these variables. The analysis of suspended sediment particle size has indicated that average percentage of clay, silt and sand was 1.4, 67.3 and 31.3 respectively indicating a higher content of silt followed by sand. There was no significant variation in the content of clay, silt and sand during the ablation period.
Also, both sediment concentration and load were poorly correlated with discharge. However, the relationship between discharge and sediment load improved when monthly data was used.
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