Abstract
Flooding accounts for a large proportion of property loss and damage all over the world. Flood frequencies associated with intense periods of rainfall show increasing trends in both South Africa and globally. As a result, preventative measures to mitigate property loss and damage play an increasingly important role in the built environment. In hydrology terms, flood-lines refer to the maximum extent of a flood event that can either be measured retrospectively after a rainfall event of significance through in-situ measurements or proactively simulated through a digital representation of the assessment area. The proactive approach has inherent benefits of being able to run a multitude of volumes to illustrate the effect of various rainfall events on a river system but is dependent on the quality of data being fed into the system itself. A key component to the data input includes elevation information that defines the topographical environment around the river system. There are several elevation sources and methods of interpolating to create continuous elevation surfaces that can be utilized for an area-based flood modelling scenario. The usage and application of many of these sources are affected by the cost and time factors which often place restrictions on the level of detail and accuracy that the digital representation of the river system captures. Due to the multitude of variables with regards to the elevation data inputs, there is a need to 1) identify the best-suited interpolation techniques to accurately represent a hydrological environment; and 2) to identify an optimal elevation source to accurately depict a flood-line output...
M.Sc. (Geography)