ABSTRACT
In this study, a physical hydraulic model investigation was conducted to evaluate the performance of a stepped overflow spillway. The spillway has a standard ogee profile with continuous steps cut into the spillway weir down-stream face just below the crest to the toe. The experiment was carried out on three models of the spillway weir, two of the models were of the same scale ratio 1:1OO of the prototype, one model has the stepped down - stream face while the other is unstepped, which was used to compare their test results. Discharges were allowed to pass over each of the weirs and readings were noted and compared. The third model is a bigger model of 1:50 which is also of the stepped face type. The investigation demonstrated that this stepped spillway is quite effective at dissipating energy and smooth flow transition from the spillway crest to the stepped face is easily achieved.