Sediment transport rating curves for Deviar watershed in the Western Ghat region of Kerala State - a case study

摘要

Even though erosion and sediment transport is one of the very serious problems of the humid tropics of Western Ghat region, their quantitative assessment is quite often tedious and time consuming. This paper presents a sediment transport regression model for Deviar watershed in the Western Ghat region. It will help in quick assessment of suspended sediment transport for design and implementation of soil erosion control measures, assessment of reservoir sedimentation, loss of soil fertility etc. Suspended sediment movement and stream flow have been monitored continuously for a period of three years in Deviar watershed as a part of a detailed hydrological investigation and studies in highland and midland regions of Kerala state. Stream discharges were observed with the help of water current meters and water samples were collected with 'Punjab Type' water samplers at selected four stream gauging stations in the watershed. The water samples were analyzed in the laboratory established in the watershed. Standard gravimetric procedure was adopted to determine the sediment concentration of water samples. Area velocity method was used to determine the stream discharge. A set of sediment rating curves relating suspended sediment concentration and stream discharge by fitting the regression curves were prepared for the above stream gauging stations. The above regression model showed a correlation coefficient of more than 0.70 and the model is found useful in estimating the sediment load on days for which no measurements are available.