A simplified model of pathogenic pollution for managing beaches

Existing models for urban runoff water quality and dispersion in the coastal zone are cumbersome for application to everyday management of beach use. A simplified model is therefore proposed and tested using a case study. The model captures the key physical processes involved in mixing and dispersion of pathogenic pollution at beaches, and should therefore have some generality. Simulations using the model are shown to adequately reproduce measurements at the case study site. The utility of the model is demonstrated by analysing a specific case of poor water quality at one of the beaches and by using it to estimate the reduction in pollution loadings needed to meet water quality guidelines. Key words: beach-water quality model, pathogenic pollution, storm-water runoff, E. coli Water SA Vol.31(1) 2005: 47-52