Assessing microbiological water quality in drinking water distribution systems with disinfectant residual using flow cytometry

Soft waters characterised with low alkalinity tend to reduce the lifetime of pipes in drinking water distribution systems. Consequently, the corrosion induced is likely to deteriorate water quality at the consumer's tap. Two different types of treatment methods are commonly used to control the corrosion effects of soft waters: (i) the addition of phosphate corrosion inhibitors, and (ii) the remineralisation process. In order to facilitate the decision making of network operator to use suitable treatment methods, a comparative pilot-scale experiment was performed. The above two treatment strategies were tested using pipes representing both drinking water distribution systems (used materials: cast iron and steel) and household plumbing systems (used material: copper). The impact of the two techniques was assessed by means of water quality monitoring (pH, metal leaching, etc) and of corrosion measurements using electrochemical probes as well as weight-loss coupons. The results obtained after a 15 month long experiment showed that remineralisation method was clearly the most effective way to control soft water corrosion. The implementation of this method resulted in a 50% reduction in metals leaching and about 40% decrease in iron corrosion rates.

Download Full-text

Monitoring of Chlorine Concentration in Drinking Water Distribution Systems Using an Interval Estimator

International Journal of Applied Mathematics and Computer Science ◽

10.2478/v10006-007-0019-y ◽

2007 ◽

Vol 17 (2) ◽

pp. 199-216 ◽

Cited By ~ 21

Author(s):

Rafał Łangowski ◽

Mietek Brdys

Keyword(s):

Water Quality ◽

Drinking Water ◽

Distribution Systems ◽

Water Distribution ◽

Water Distribution Systems ◽

Chlorine Concentration ◽

State Variables ◽

Drinking Water Distribution Systems ◽

Drinking Water Distribution ◽

Interval Estimator

Monitoring of Chlorine Concentration in Drinking Water Distribution Systems Using an Interval EstimatorThis paper describes the design of an interval observer for the estimation of unmeasured quality state variables in drinking water distribution systems. The estimator utilizes a set bounded model of uncertainty to produce robust interval bounds on the estimated state variables of the water quality. The bounds are generated by solving two differential equations. Hence the numerical efficiency is sufficient for on-line monitoring of the water quality. The observer is applied to an exemplary water network and its performance is validated by simulations.

Download Full-text

Spatial diversity of chlorine residual in a drinking water distribution system: application of an integrated fuzzy logic technique

Journal of Hydroinformatics ◽

10.2166/hydro.2014.092 ◽

2014 ◽

Vol 17 (2) ◽

pp. 293-306 ◽

Cited By ~ 2

Author(s):

Donatella Termini ◽

Gaspare Viviani

Keyword(s):

Water Quality ◽

Fuzzy Logic ◽

Drinking Water ◽

Distribution Systems ◽

Water Distribution ◽

Water Distribution Systems ◽

Residual Chlorine ◽

Drinking Water Distribution Systems ◽

Drinking Water Distribution ◽

Fuzzy Logic Technique

A reduction in the concentration of chlorine, which is used as a chemical disinfectant for water in drinking water distribution systems, can be considered to be an index of the progressive deterioration of water quality. In this work, attention is given to the spatial distribution of the residual chlorine in drinking water distribution systems. The criterion for grouping the water-quality parameters normally used is highly subjective and often based on data that are not correctly identified. In this paper, a cluster analysis based on fuzzy logic is applied. The advantage of the proposed procedure is that it allows a user to identify (in an automatic way and without any specific assumption) the zonation of the network and easily calibrate the unknown parameters. An analysis of the correlation between the sampling sites for the residual chlorine has been used to assess the applicability of the procedure.

Download Full-text

Characterising and understanding the impact of microbial biofilms and the extracellular polymeric substance (EPS) matrix in drinking water distribution systems

Environmental Science Water Research & Technology ◽

10.1039/c6ew00039h ◽

2016 ◽

Vol 2 (4) ◽

pp. 614-630 ◽

Cited By ~ 32

Author(s):

Katherine E. Fish ◽

A. Mark Osborn ◽

Joby Boxall

Keyword(s):

Water Quality ◽

Drinking Water ◽

Distribution Systems ◽

Water Distribution ◽

Water Distribution Systems ◽

Effective Management ◽

Drinking Water Distribution Systems ◽

Microbial Biofilms ◽

Drinking Water Distribution ◽

The Impact

Drinking water distribution systems (DWDS) contain complex microbial biofilm communities. Understanding the ecology of these biofilms is critical for effective management of DWDS infrastructure and maintenance of water quality.

Download Full-text