A comparative assessment of bacteriophages as tracers and models for virus removal waste stabilisation ponds

Abstract

The suitability of five strains of bacteriophage as hydraulic tracers and as models of pathogenic virus removal in waste stabilisation ponds was determined in vitro. The bacteriophages investigated included Serratia marcescens, Pseudomonas syringae, Erwinia amanas, and two phages of Erwinia amylovora. The study modeled the survival of these bacteriophages under the physico-chemical conditions typically encountered in WSP systems. This demonstrated that the selected phages, were greatly affected by increased pH and sunlight, but survived for sufficient time at moderate pH levels (6.5-8.5) to justify their use as tracers in full-scale WSPs. Furthermore, their survival/removal in adjusted physico-chemical conditions, suspended solids concentration and temperature, was comparable to human pathogenic viruses. It was concluded that these phages are potentially useful tracers and indicators for pathogenic viruses in WSPs.