Abstract: By founding integral hydraulic transition process mathematics calculation model, combined with the physical model test, the arrangement of the diversion system was optimized. The rationality of cancellation of large- sized surge chamber was proved, section area of the upstream impedance surge chamber was selected, base plate elevation of the head surge chamber and the maximal design pressure for the base plate of the surge chamber were fixed, the advantage and disadvantage of the differential and other kinds of surge shafts were discussed, as well as the error influence factors in the diversion system hydraulic calculation and model test were introduced. It saved project investment and enhanced the research ability of the engineers.