title: Bacterial water quality and network hydraulic characteristics: a field study of a small, looped water distribution system using culture-independent molecular methods.
abstract: OBJECTIVE
  To determine the spatial and temporal variability in the abundance, structure and composition of planktonic bacterial assemblages sampled from a small, looped water distribution system and to interpret results with respect to hydraulic conditions.
  
  
  RESULTS
  Water samples were collected from five sampling points, twice a day at 06:00 h and 09:00 h on a Monday (following low weekend demand) and a Wednesday (higher midweek demand). All samples were fully compliant with current regulated parameter standards. This study did not show obvious changes in bacterial abundance (DAPI count) or community structure Denaturing gradient gel electrophoresis analysis with respect to sample site and hence to water age; however, the study did show temporal variability with respect to both sampling day and sample times.
  
  
  CONCLUSIONS
  Data suggests that variations in the bacterial assemblages may be associated with the local system hydraulics: the bacterial composition and numbers, over short durations, are governed by the interaction of the bulk water and the biofilm influenced by the hydraulic conditions.
  
  
  CONCLUSIONS
  This study demonstrates general stability in bacterial abundance, community structure and composition within the system studied. Trends and patterns supporting the transfer of idealized understanding to the real world were evident. Ultimately, such work will help to safeguard potable water quality, fundamental to public health.
authors.affiliation: Department of Civil and Structural Engineering, Pennine Water Group, The University of Sheffield, Sheffield, UK.
authors.forename: R
authors.initials: R
authors.lastname: Sekar
authors.forename: P
authors.initials: P
authors.lastname: Deines
authors.forename: J
authors.initials: J
authors.lastname: Machell
authors.forename: A M
authors.initials: AM
authors.lastname: Osborn
authors.forename: C A
authors.initials: CA
authors.lastname: Biggs
authors.forename: J B
authors.initials: JB
authors.lastname: Boxall
mesh_terms: D001419:Bacteria / Q000145:classification; D058491:Bacterial Load; D018441:Biofilms; D060766:Drinking Water / Q000382:microbiology*; D006801:Humans; D060753:Water Quality
chemical_list: D060766:Drinking Water