After the impoundment of the Three Gorges reservoir (TGR),the velocity of the left channel of Huanghuacheng reach in the permanent backwater region of TGR deposited badly.The depositions are fine sediments with median diameters of about 0.01 mm,thus it is controversial to apply the traditional waterway dredging theory.A diversion dam-based regulation scheme is proposed to improve the diversion ratio and enlarge the velocity of the left channel.Numerical simulation and model experiment of renovation plan show that the velocity of the left channel reaches the sediment transportation-velocity,indicating that the deposition area keeps no more scour or deposition.The regulation method which combines waterway dredging with diversion dam is proposed.