[en] This report presents the user's manual of the general-usage computer code SEDONE for simulating fast-transient (tidal-transient), one-dimensional hydrodynamic and three-layer, variable-size sediment concentration conditions in controlled rivers and tidal estuaries. The code is particularly designed for application to site-specific problems that require accurate predictions of the sedimentation phenomena under severely reversing flow conditions. Input data to the code includes modified geometry contours of the channel cross-sections with corrections for the embayment areas, flow conditions at the controlled dams, tidal conditions at the ocean ends, rainfall conditions in the geographical region, stream flow, drainage flow, and ground-water-seepage flow conditions, and the physical properties of the sediment size classes that determine the settling and resuspension effects which control the sedimentation. The formats of the input data are completely generalized. The code also has a user-specified option to include only the simulations of sediment concentration conditions by incorporating previously computed and stored results for the surface elevation and flow rate conditions, thereby excluding the computations for the solution of the hydrodynamic conditions. This option substantially reduces the computational cost of repeated simulations