Water distribution systems as living ecosystems: Impact on taste and odor

Abstract

Six waters from different U.S. cities with known diverse taste and odor (TO) evaluations were selected for additional microbial characterization. All waters were subjected to microbial and cultural analyses, and four of the waters were further analyzed by cloning and sequencing of community 16S rRNA. The purpose of the study was to evaluate water distribution systems as living ecosystems, and the impact of these ecosystems on TO. All waters had total bacterial counts of at least 10(3) per ml. The water with lowest TO ranking had 10(6) total counts per ml. Community DNA sequence analysis identified diverse bacterial communities representing five different phyla and over forty genera. Included in this diversity were heterotrophic and autotrophic species that were both aerobic or anaerobic. Additionally, waters with the lowest TO evaluations contained significant sulfide concentrations, as well as bacteria associated with both the oxidation and reduction of inorganic sulfur compounds. Low redox conditions could have resulted in the reduced sulfur compounds and concomitant TO related problems, and an increase in redox could help alleviate these problems. Overall, data show that water distribution systems contain living ecosystems that evolve based on specific environments within particular distribution systems that impact water TO.

Inflammatory responses and potencies of various lipopolysaccharides from bacteria and cyanobacteria in aquatic environments and water supply systems

“…including A. lwoffii are known not just as opportunistic pathogens but also ubiquitous habitant in biofilm in water distribution systems. (Scott and Pepper, 2010;Vaz-Moreira et al, 2013;Kelly et al, 2014). This result suggests that inflammatory potency can increase with the regrowth of Acinetobacter sp.…”

“…Additionally, Kalmbach et al (1999) reported that Aquabacterium commune is a dominant and ubiquitous community member in biofilms accumulated in several distribution systems in Hamburg, Berlin, Mainz, and Stockholm, which had different water sources and treatment processes. Acinetobacter lwoffii, which is known as an opportunistic pathogen, was also widely detected in water supply systems (Scott and Pepper, 2010). If these ubiquitously present bacteria, which have potent endotoxic activity, multiply in water distribution systems, significant elevations of endotoxin levels in water could occur.…”

“…were dominant species in water samples taken at a hospital via a storage tank. Scott and Pepper (2010) identified frequently detected bacterial species in tap water samples in the United States as Sphingomonas sp., Acidovorax sp., Aquabacterium sp., and Acinetobacter sp. based on the homology of 16S rRNA sequences.…”

Biological Stability of Drinking Water: Controlling Factors, Methods, and Challenges

“…Moreover, specific bacteria produce molecules affecting taste and odor of water. Typical examples are actinomycetes, which produce geosmin, responsible for an earthy-muddy water taste ( Srinavasan and Sorial, 2011 ), and bacteria involved in the sulfur cycle (e.g., sulfate reducing or oxidizing bacteria) that can promote a sulfur-based odor ( Scott and Pepper, 2010 ). Besides, yeast, fungi, and algae have also been recorded in drinking water and some of these organisms have been associated with taste and odor complaints ( Block et al, 1993 ; Sibille et al, 1998 ; van der Wielen and van der Kooij, 2013 ).…”

Near Real-Time Detection of E. coli in Reclaimed Water

“…Bacteria are prokaryotic microorganisms that are the least complex of living microbes but offer the greatest metabolic flexibility and diversity. Bacteria can thrive within a variety of environments, including potable water distribution systems [ 1 ]. Despite deliberate disinfection of water via chlorine by utilities, almost all potable water within distribution systems can still contain vast populations of bacteria of up to 10 6 culturable cells per mL.…”