Comprehensive water testing analyses for improved water management: coliforms, coliphage and cholesterol

Abstract

Abstract The use of faecal coliforms as indicators is the traditional approach of testing water quality. Unfortunately, for a comprehensive water quality analysis, there is an increasing body of evidence that demonstrates coliforms as insufficient indicators for water quality assessment. Therefore, during the last two decades, alternative water testing approaches such as the use of coliphage as well as cholesterol detection have gained popularity. In the present study, we evaluated and compared the reliability of data from three different indicators that included coliforms (Streptococcus), coliphage and cholesterol. Four sites were chosen for sample collection and these included one site from Haart river (HR1) and three sites from Barberspan (BP1, 2 and 3) in the North West Province of South Africa. Samples were collected during winter and summer seasons. Collected samples were subjected to different analyses for detection of coliphage, coliforms and cholesterol. Faecal indicator bacteria were detected at all sites and in some cases were relatively high (HR1: 287 cfu/100 mL faecal coliform and 228.6 cfu/100 mL faecal streptococci; BP1: 1,730 cfu/100 mL Escherichia coli). The HR1 site consistently had the highest levels of bacterial faecal indicators of the four sampling sites. Most notably, faecal streptococci were detected in higher numbers than any other bacterial indicator. A significant finding was the general higher levels of faecal indicator markers at the BP3. Based on the outcome of this study, a combination of these indicators offers a comprehensive and promising approach for monitoring water quality.