Estimating transmission losses along the Limpopo River: an overview of alternative methods

This paper gives a summary of methods that were considered to investigate transmission losses along the Limpopo River. Four criteria (information, practicality, solution-type, and time and spatial scale) were set to evaluate possible approaches. These include: statistical methods; methods using a storage loss concept; methods using a streamflow aquifer interaction equation based on the head difference between surface and groundwater; and finally methods coupling unsteady surface flow equations with groundwater flow equations. Each method is described and evaluated against the specific conditions of the Limpopo River. This paper provides a basis for further investigation of transmission losses along the Limpopo River and recommends an approach with a moderate level of complexity given the limited information available and the benefits associated with each method for the Limpopo River.