The Removal of Excreted Bacteria and Viruses in Deep Waste Stabilization Ponds in Northeast Brazil

• DOI: 10.2166/wst.1987.0236
• Publication Date: 2018-05-18T12:13:21Z
• Authors: J. I. Oragui; T. P. Curtis; S. A. Silva; D. D. Mara
• Keywords: 0207 environmental engineering; 02 engineering and technology; 01 natural sciences; 6. Clean water; 0105 earth and related environmental sciences

The removal of excreted bacteria (faecal coliforms, faecal streptococci, Clostridium perfringens, total and sorbitol-fermenting bifidobacteria, salmonellae and thermophilic campylobacters) and viruses (enterovirus and rotavirus) in a series of deep anaerobic, facultative and maturation ponds (depth range: 2.8 - 3.4 m), with an overall retention time of 21 days and a mean mid-depth temperature of 27°C, was studied. Thermophilic campylobacters, bifidobacteria and salmonellae were not detected after 11, 16 and 21 days' retention respectively. Faecal coliforms, faecal streptcocci and Cl. perfringens were reduced by 4, 4 and 2 orders of magnitude respectively, and enteroviruses arid rotaviruses both by 3 orders. The results indicate that pathogen removal in deep ponds is similar to that in ponds of normal depth.