A case study indicated that the high number of pathogenic micro-organisms in the Rietspruit, South Africa, can impact water uses. Factors contributing to high microbial numbers are high density population with limited services provided per site, sabotage of the sewage reticulation system, lack of money and management skills to provide the essential services and limited integrated development planning for the catchment.

Due to non-steady state conditions in the catchment, the specific use and physical characteristics of the river and the difficulty in determining flow, the usefulness of a steady-state stream water quality model as a management tool is limited. Determining the decay rate of micro-organisms by means of chamber studies, may be a first step to predict microbial water quality. Involving the community in preventing microbial pollution may be a more appropriate tool for microbial water quality management in developing areas.