ABSTRACT
The main dam of the Bovane reservoir is the 50 m high Mhlathuzane RCC dam, including headworks (outlets, operation infrastructure) and stepped spillway. The maximum width of the spillway is limited to approximately 42 m according to the downstream conditions of the riverbed. To handle the design flood of HQ10,000 = 5050 m3/s, a 260 m wide fuse-plugged emergency spillway had to be provided. It restricts the maximum water depth on the weir of the stepped spillway to hd = 2.15 m, following the results of a flood routing. The downstream inclination of the spillway was chosen according to the dam geometry to 1:n = 1:0.75, α = 53°, with a step height of h = 0.60 m.
