Abstarct: In recent decades, although dam construction has increased in number and multiplicity, unfortunately, most of these dams are subjected to sediment accumulation during their operation period. As a scientific way, Sediment Bypass Tunnels (SBTs) could be hired to solve this problem. They are deviant channels that convey the current containing sediments from the upstream of the reservoir to the downstream of the dam. In this research, the effect of hydraulic parameters of flow and changes in the angle of plates on sediment transport and deviated flow have been investigated through applying submerged plates on the entrance of a 90-degree diversion channel for sediment transport and then, compared with the state without using submerged plates. The experiments were conducted on a 10-meter-long Laboratory Flume, with a main channel of 60 cm width and a secondary channel of 30 cm width and a height of 75 cm. In this regard, the variables of Froude number and flow depth in three angles of 30, 45, and 60 degrees were studied. Then 18 experiments were simulated with SSIIM2 numerical model and compared with laboratory results and verifiedExperimental results show that increasing the Froude number from 0.65 to 0.98 on average causes a 20% decrease in deviated flow and a 44% decrease in deviated sediments to the sediment bypass tunnel. Also, the effect of flow depth changes on performance is decreased drastically by an increase of 1.5 times in the relative width of the diversion channel; however, in lower width ratios, the sensitivity of the diversion tunnels to the flow depth is very significant where with an increase of 1.5 times in the relative width of the diversion channel from 0.33 to 0.50, the Coefficient of Performance (CoP) increases by 39%. Moreover, by increasing the angle of the submerged plates from 30 to 60 degrees, the rate of deviated flow decreases by about 6% at a relative depth of 0.08, 3% and 1% at higher relative depths (0.12 and 0.16 respectively) where the performance sensitivity of diversion channels to flow depth changes in lower angles is negligible and reaches to 1% at an angle of 30 degrees. Nevertheless, increasing the angle of submerged plates to 45 and 60 degrees would increase the Coefficient of Performance (CoP) of sediment bypass tunnels by 10% and 24%, respectively. Consequently, it was observed that by decreasing the flow depth, submerged plates with an angle of 60 degrees demonstrated the optimum sediment transport option with the highest performance. baxsed on dimensional analysis and using the Genetic Algorithm (GA) the best equation proposed to estimate the deviated sedimentation flow to the secondary channel. Comparison of numerical simulation results of the SSIIM model showed that the numerical model error rate was about 18% and the mean of the Nash–Sutcliffe model efficiency coefficient (NSE) was estimated to be 0.87 for the laboratory and numerical data, Given this value, the correct performance of the model can be deduced.