Cross, Anthony Leighton2018-04-092018-04-091991https://hdl.handle.net/10539/24308A project report submitted to the Faculty of Engineering, University of the Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the degree Of Master Of Science in Engineering.The temporal distribution of rainfall can have a significant effect on peak runoff, especially so in the small catchments that are typical of the Witwatersrand. This report investigates the shape of the natural hyetoraph and its use in the analysis of peak runoff. It describes the climatology of the sub-continent and rain-producing systems. Then more specifically, aspects of rainfall over Johannesburg are discussed. Some Of the more commonly-used temporal distributions of rainfall are reviewed and the relationship between intensity-time distributions and mass curves is illustrated. Mass curves are derived using data from a rain gauge in Norwood, Johannesburg. The data is analysed with the assistance of a computer program and classified into quartiles. The quartiles are further analysed in an attempt to define their characteristics in greater detail. The mass curves are used wIth a hydrological model to generate hydrographs. The values of runoff peaks are found to be comparable with those obtained using currently accepted temporal rainfall distributions.enHydrology -- Research -- South Africa -- Transvaal.Depth-area-duration (Hydrometeorology)Climatology -- Research -- South Africa.Rain and rainfall -- South Africa -- Transvaal.Thesis