Authors: T. T. Tanyimboh and N. Parbhoo
Conference: 15th International Conference on Urban Drainage
Date: October 25-28, 2021
Research was carried out to assess changes in extreme rainfall properties over time for the area surrounding the National Route 1 Section 29 (N1-29), located in Limpopo, South Africa. The study examined the changes in return levels for 1920-1970 and 1969-2019. The analysis showed that there is substantial change in the intensity of extreme rainfall events with increases of up to 16.9% and 14.3%, for the 20-year and 50-year return levels, respectively. This indicates an increase in the depth-duration-frequency of extreme rainfall events in the area for the period considered. Furthermore, it was found that almost all the major culverts in the section were unable to accommodate the stipulated design flood, indicating that the structures are highly susceptible to the effects of extreme rainfall events.
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