Optimal Time Step Length to Minimize Uncertainty of Zonal Water Balance Calculation in Drinking Water Distribution Systems

Water balance calculation is a well-known and adapted method to analyze district-metered areas (DMAs) of drinking water distribution system. Other application of water balance results can be training dataset for consumption forecast, monitoring and managing water loss. The vast amount of application makes it a very powerful tool, which is in contrary sensitive to the accuracy of the calculation. The uncertainty of flow metering decreases as the length of the time step decreases, however, the uncertainty of stored volume measurement in tanks increases. Investigation of the limitations of water balance calculation in regard to uncertainty is necessary to develop an analytical solution for optimal calculation time step.

Control of biofilm growth in drinking water distribution system by biodegradable carbon and disinfectant residuals

Water Science & Technology Water Supply ◽

10.2166/ws.2006.063 ◽

2006 ◽

Vol 6 (2) ◽

pp. 147-151 ◽

Cited By ~ 1

Author(s):

X.-J. Zhang ◽

W. Lu

Keyword(s):

Drinking Water ◽

Distribution System ◽

Distribution Systems ◽

Water Distribution ◽

Free Water ◽

Planktonic Cell ◽

Biofilm Growth ◽

Bacteria Growth ◽

Biofilm growth in drinking water distribution systems was studied in an annular reactor system which was designed to model the hydraulic conditions in water mains. Experiments were performed with chlorine-free water as well as with different disinfectant (chlorine or chloramine) residuals and different AOC concentrations added to the reactor influent to examine the effect of disinfectant residuals and AOC concentrations on biofilm accumulation and planktonic cell numbers. The dynamic parameters of bacteria growth were calculated in water with different disinfectant (chlorine or chloramine) and the results indicated that monochloramine may be more effective than free chlorine for control of biofilm accumulation.

Water quality event detection and customer complaint clustering analysis in distribution systems

Water Science & Technology Water Supply ◽

10.2166/ws.2012.030 ◽

2012 ◽

Vol 12 (5) ◽

pp. 580-587 ◽

Cited By ~ 3

Author(s):

Stephen Mounce ◽

John Machell ◽

Joby Boxall

Keyword(s):

Water Quality ◽

Drinking Water ◽

Distribution System ◽

Distribution Systems ◽

Water Distribution ◽

Water Source ◽

Water Quality Monitoring ◽

Water Utility ◽

Drinking Water Distribution ◽

Historic Data

Safe, clean drinking water is a foundation of society and water quality monitoring can contribute to ensuring this. A case study application of the CANARY software to historic data from a UK drinking water distribution system is described. Sensitivity studies explored appropriate choice of algorithmic parameter settings for a baseline site, performance was evaluated with artificial events and the system then transferred to all sites. Results are presented for analysis of nine water quality sensors measuring six parameters and deployed in three connected district meter areas (DMAs), fed from a single water source (service reservoir), for a 1 year period and evaluated using comprehensive water utility records with 86% of event clusters successfully correlated to causes (spatially limited to DMA level). False negatives, defined by temporal clusters of water quality complaints in the pilot area not corresponding to detections, were only approximately 25%. It was demonstrated that the software could be configured and applied retrospectively (with potential for future near real time application) to detect various water quality event types (with a wider remit than contamination alone) for further interpretation.

Prediction of chlorine and trihalomethanes concentration profile in bulk drinking water distribution systems from laboratory data

Water Science & Technology Water Supply ◽

10.2166/ws.2003.0110 ◽

2003 ◽

Vol 3 (1-2) ◽

pp. 239-246 ◽

Cited By ~ 2

Author(s):

G. Kastl ◽

I. Fisher ◽

V. Jegatheesan ◽

J. Chandy ◽

K. Clarkson

Keyword(s):

Drinking Water ◽

Distribution System ◽

Distribution Systems ◽

Water Distribution ◽

Laboratory Data ◽

Water Distribution Systems ◽

Optimum Level ◽

Drinking Water Distribution ◽

Chlorine Decay

Nearly all drinking water distribution systems experience a “natural” reduction of disinfection residuals. The most frequently used disinfectant is chlorine, which can decay due to reactions with organic and inorganic compounds in the water and by liquid/solids reaction with the biofilm, pipe walls and sediments. Usually levels of 0.2-0.5 mg/L of free chlorine are required at the point of consumption to maintain bacteriological safety. Higher concentrations are not desirable as they present the problems of taste and odour and increase formation of disinfection by-products. It is usually a considerable concern for the operators of drinking water distribution systems to manage chlorine residuals at the “optimum level”, considering all these issues. This paper describes how the chlorine profile in a drinking water distribution system can be modelled and optimised on the basis of readily and inexpensively available laboratory data. Methods are presented for deriving the laboratory data, fitting a chlorine decay model of bulk water to the data and applying the model, in conjunction with a simplified hydraulic model, to obtain the chlorine profile in a distribution system at steady flow conditions. Two case studies are used to demonstrate the utility of the technique. Melbourne’s Greenvale-Sydenham distribution system is unfiltered and uses chlorination as its only treatment. The chlorine model developed from laboratory data was applied to the whole system and the chlorine profile was shown to be accurately simulated. Biofilm was not found to critically affect chlorine decay. In the other case study, Sydney Water’s Nepean system was modelled from limited hydraulic data. Chlorine decay and trihalomethane (THM) formation in raw and treated water were measured in a laboratory, and a chlorine decay and THM model was derived on the basis of these data. Simulated chlorine and THM profiles agree well with the measured values available. Various applications of this modelling approach are also briefly discussed.

Whole-Genome Sequences of Four Strains Closely Related to Members of the Mycobacterium chelonae Group, Isolated from Biofilms in a Drinking Water Distribution System Simulator: TABLE 1

Genome Announcements ◽

10.1128/genomea.01539-15 ◽

2016 ◽

Vol 4 (1) ◽

Cited By ~ 2

Author(s):

Vicente Gomez-Alvarez ◽

Randy P. Revetta

Keyword(s):

Drinking Water ◽

Distribution System ◽

Distribution Systems ◽

Water Distribution ◽

Draft Genome ◽

Drinking Water Distribution System ◽

Genome Sequences ◽

Mycobacterium Chelonae ◽

We report here the draft genome sequences of four Mycobacterium chelonae strains from biofilms subjected to a “chlorine burn” in a chloraminated drinking water distribution system simulator. These opportunistic pathogens have been detected in hospital and municipal water distribution systems, in which biofilms have been recognized as an important factor for their persistence.

Occurrence of Mycobacteria in Water Treatment Lines and in Water Distribution Systems

Applied and Environmental Microbiology ◽

10.1128/aem.68.11.5318-5325.2002 ◽

2002 ◽

Vol 68 (11) ◽

pp. 5318-5325 ◽

Cited By ~ 114

Author(s):

Corinne Le Dantec ◽

Jean-Pierre Duguet ◽

Antoine Montiel ◽

Nadine Dumoutier ◽

Sylvie Dubrou ◽

...

Keyword(s):

Drinking Water ◽

Distribution System ◽

Distribution Systems ◽

Water Distribution ◽

Sand Filtration ◽

Mycobacterial Species ◽

Slow Sand Filtration ◽

Drinking Water Distribution ◽

Rapid Sand Filtration

ABSTRACT The frequency of recovery of atypical mycobacteria was estimated in two treatment plants providing drinking water to Paris, France, at some intermediate stages of treatment. The two plants use two different filtration processes, rapid and slow sand filtration. Our results suggest that slow sand filtration is more efficient for removing mycobacteria than rapid sand filtration. In addition, our results show that mycobacteria can colonize and grow on granular activated carbon and are able to enter distribution systems. We also investigated the frequency of recovery of mycobacteria in the water distribution system of Paris (outside buildings). The mycobacterial species isolated from the Paris drinking water distribution system are different from those isolated from the water leaving the treatment plants. Saprophytic mycobacteria (present in 41.3% of positive samples), potentially pathogenic mycobacteria (16.3%), and unidentifiable mycobacteria (54.8%) were isolated from 12 sites within the Paris water distribution system. Mycobacterium gordonae was preferentially recovered from treated surface water, whereas Mycobacterium nonchromogenicum was preferentially recovered from groundwater. No significant correlations were found among the presence of mycobacteria, the origin of water, and water temperature.

Hydraulic optimization of the physical parameters of a drinking water distribution system

Journal of Physics Conference Series ◽

10.1088/1742-6596/2139/1/012013 ◽

2021 ◽

Vol 2139 (1) ◽

pp. 012013

Author(s):

C A Bonilla-Granados ◽

N J Cely-Calixto ◽

G A Carrillo Soto

Keyword(s):

Drinking Water ◽

Distribution System ◽

Distribution Systems ◽

Water Distribution ◽

Water Distribution Network ◽

Hydraulic Modeling ◽

Physical Parameters ◽

Drinking Water Distribution System ◽

Abstract Drinking-water distribution systems are generally designed with methodologies based on trial-and-error tests, which generate feasible results. However, these trials are not the most economical and reliable solution since they do not consider the optimization of the network. For the present work, the hydraulic model of the drinking water distribution network of San José de Cúcuta, Colombia, was optimized by applying the concept of resilience rate and minimum cost. The development of the work consisted of the hydraulic modeling of the physical components of the network in EPANET software, as well as the application of calculations of the connectivity coefficient and the unitary power of each section. With the data obtained from the modeling and calculations, the physical parameters were optimized, and the cost-benefit ratio was estimated. It was found that the current drinking water distribution system does not have a power surplus to overcome a system failure. The optimization increased the total energy surplus of the network (261%) and the resilience rate (585%). Also, the connectivity coefficient was improved with an average value of 0.95. The hydraulic optimization methodology applied resulted in a network resilient to system failures.

Spatial variation of loose deposit characteristics in a 40 km long operational drinking water distribution system

Environmental Science Water Research & Technology ◽

10.1039/c9ew00391f ◽

2019 ◽

Vol 5 (10) ◽

pp. 1689-1698

Author(s):

Xu Ma ◽

Guiwei Li ◽

Ying Yu ◽

Ruya Chen ◽

Yao Zhang ◽

...

Keyword(s):

Drinking Water ◽

Distribution System ◽

Distribution Systems ◽

Water Distribution ◽

Eastern China ◽

System P ◽

Loose Deposit ◽

Discoloration problems have occurred in drinking water distribution systems continuously for several years in a rural area of eastern China.

A biochemical multi-species quality model of a drinking water distribution system for simulation and design

International Journal of Applied Mathematics and Computer Science ◽

10.2478/amcs-2013-0043 ◽

2013 ◽

Vol 23 (3) ◽

pp. 571-585 ◽

Cited By ~ 10

Author(s):

Krzysztof Arminski ◽

Tomasz Zubowicz ◽

Mietek A. Brdys

Keyword(s):

Drinking Water ◽

Distribution System ◽

Distribution Systems ◽

Water Distribution ◽

Heterotrophic Bacteria ◽

Ammonia Oxidizing Bacteria ◽

Large Set ◽

Monitoring And Control ◽

Quality Model ◽

Abstract Drinking Water Distribution Systems (DWDSs) play a key role in sustainable development of modern society. They are classified as critical infrastructure systems. This imposes a large set of highly demanding requirements on the DWDS operation and requires dedicated algorithms for on-line monitoring and control to tackle related problems. Requirements on DWDS availability restrict the usability of the real plant in the design phase. Thus, a proper model is crucial. Within this paper a DWDS multi-species quality model for simulation and design is derived. The model is composed of multiple highly inter-connected modules which are introduced to represent chemical and biological species and (above all) their interactions. The chemical part includes the processes of chloramine decay with additional bromine catalysis and reaction with nitrogen compounds. The biological part consists of both heterotrophic and chemo-autotrophic bacteria species. The heterotrophic bacteria are assumed to consume assimilable organic carbon. Autotrophs are ammonia oxidizing bacteria and nitrite oxidizing bacteria species which are responsible for nitrification processes. Moreover, Disinfection By-Products (DBPs) are also considered. Two numerical examples illustrate the derived model’s behaviour in normal and disturbance operational states.

Effect of Phosphorus on Survival of Escherichia coli in Drinking Water Biofilms

Applied and Environmental Microbiology ◽

10.1128/aem.00313-07 ◽

2007 ◽

Vol 73 (11) ◽

pp. 3755-3758 ◽

Cited By ~ 30

Author(s):

Talis Juhna ◽

Dagne Birzniece ◽

Janis Rubulis

Keyword(s):

Escherichia Coli ◽

Drinking Water ◽

Distribution System ◽

Distribution Systems ◽

Water Distribution ◽

Phosphorus Addition ◽

E Coli ◽

ABSTRACT The effect of phosphorus addition on survival of Escherichia coli in an experimental drinking water distribution system was investigated. Higher phosphorus concentrations prolonged the survival of culturable E. coli in water and biofilms. Although phosphorus addition did not affect viable but not culturable (VBNC) E. coli in biofilms, these structures could act as a reservoir of VBNC forms of E. coli in drinking water distribution systems.

Draft Genome Sequence of Two Sphingopyxis sp. Strains, Dominant Members of the Bacterial Community Associated with a Drinking Water Distribution System Simulator

Genome Announcements ◽

10.1128/genomea.00183-16 ◽

2016 ◽

Vol 4 (2) ◽

Cited By ~ 2

Author(s):

Vicente Gomez-Alvarez ◽

Stacy Pfaller ◽

Randy P. Revetta

Keyword(s):

Drinking Water ◽

Distribution System ◽

Distribution Systems ◽

Water Distribution ◽

Draft Genome ◽

Antibiotic Resistance Genes ◽

Drinking Water Distribution System ◽

Class 1 Integron ◽

We report the draft genomes of two Sphingopyxis sp. strains isolated from a chloraminated drinking water distribution system simulator. Both strains are ubiquitous residents and early colonizers of water distribution systems. Genomic annotation identified a class 1 integron ( intI1 ) gene associated with sulfonamide ( sul1 ) and puromycin ( pac ) antibiotic resistance genes.