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A study comparing DWI held data on levels of customer contacts regarding chlorine taste and odour and chlorine levels or chlorine variability. - WT1228

Description
Chorine is used throughout the world as a disinfectant for water supply, and has probably made a greater contribution to the prevention of waterborne disease than any other form of water treatment. However, one disadvantage of the use of chlorine is that it can result in customer complaints of unpleasant taste and odour, either from chlorine itself or from reaction of chlorine with other materials in, or in contact with, the water. The complaints may be associated with high chlorine concentrations, although it is often variability in concentration rather than the concentration itself that causes complaints. Operational conditions for water treatment works or the distribution system can therefore be a significant factor in generating taste and odour complaints from consumers.

This work will provide a better understanding of the relationships between chlorine concentration, or variability in concentration, and customer contacts relating to taste and odour. This will be achieved through analysis of existing data for chlorine concentrations and customer contacts in water supply zones for the periods 2006 and 2007, taken from the DWI data system. This understanding will assist in identification of operating conditions to avoid customer complaints without compromising microbiological quality of the water.
Objective
Objectives

a) To extract information for 2006 and 2007 from DWI data systems on the contact data returns and chlorine levels in the distribution system.

b) To compare the zonal data on the levels of contacts about chlorine taste and odour with the chlorine residual data. Consideration should be given to conducting analyses based on zone size and on whether free or total chlorine is reported.

c) Devise appropriate measures of chlorine residual variability within zones based on the chlorine residual data giving consideration to possible variation due the time and location of sampling;

d) To compare the zonal data on the levels of contacts about chlorine taste and odour with the chlorine residual variability measures. Consideration should be given to conducting analyses based on zone size and on whether free or total chlorine is reported.

e) To assess the statistical significance of any correlations identified in the comparison at b and d.

f) To report on the findings.
Project Documents
• Final Report : A study comparing DWI held data on levels of customer contacts regarding chlorine taste and odour and chlorine levels or chlorine variability.   (749k)
• Executive Summary : A study comparing DWI held data on levels of customer contacts regarding chlorine taste and odour and chlorine levels or chlorine variability.   (93k)
Time-Scale and Cost
From: 2009

To: 2009

Cost: £35,795
Contractor / Funded Organisations
WRc plc
Keywords
Aesthetics              
Drinking Water              
Quality              
Water              
Fields of Study
Water Quality