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Stable channel design plays an important role for the research of stream restoration. Since sediment transport rates are highly variable in observed stream, methods for channel design must study a wide range of transport relationships to define stability conditions. The objective of study is to design stable channel for the reach of the Tapi River located between Sardar Bridge and Magdalla Bridge using hydrodynamic software. Stable channel design has carried out using Copeland method which is a part of Army Corp of Engineer (HEC-RAS) software. In the present analysis, existing sections are compared with the design sections for 2006 flood having magnitude of 9.09 cusecs (25,760 cumecs). For study purpose, Tapi River reach is selected having 31 cross sections. The bed material samples from the study reach were collected and analyzed to determine the actual grain size. This paper presents a detailed design step of cross section using Copeland method including approximating the upstream channel as trapezoidal. Results indicate that the model adequately predicts the bank shape and significant dimensions of stable channels.

Sediment transport in open channels is a challenge to hydraulics engineer. Despite including many probable significant parameters affecting sediment transport in various relationships proposed by different researchers to predict rate of sediment transport in a stream, the wide and generalized applicability is still a far goal. In pursuit of having an acceptable generalized equation for any open channel flow, the dimensionless parameters are selected from widely accepted concepts of researchers and these are correlated with sediment transport rate parameter of Einstein, in dimensionless form, to develop a regression relation. The two proposed simple models have been developed using four river data sets of Brownlie W. R. (1981). Einstein’s dimensionless sediment transport parameter is tested against a range of dimensionless flow parameters for the best correlation for the selected data sets. As a result to analysis, Yang & Lim’s and Duan’s dimensionless flow parameters were selected to finally evolve the models using regression. A performance analysis is carried out to compare the predictability of two models using statistical parameters like Correlation Coefficient, Mean Percentage Error, Discrepancy Ratio and Score using data sets other than those used for developing the models.