A Novel Statistical Model for Water Age Estimation in Water Distribution Networks

The water retention time in the water distribution network is an important indicator for water quality. The water age fluctuates with the system demand. The residual chlorine concentration varies with the water age. In general, the concentration of residual chlorine is linearly dependent on the water demand. A novel statistical model using monitoring data of residual chlorine to estimate the nodal water age in water distribution networks is put forward in the present paper. A simplified two-step procedure is proposed to solve this statistical model. It is verified by two virtual systems and a practical application to analyze the water distribution system of Hangzhou city, China. The results agree well with that from EPANET. The model provides a low-cost and reliable solution to evaluate the water retention time.

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Impact of variable speed pumps on water quality in distribution systems

Water SA ◽

10.4314/wsa.v44i3.09 ◽

2018 ◽

Vol 44 (3 July) ◽

Author(s):

Moustafa S Darweesh

Keyword(s):

Water Quality ◽

Distribution Systems ◽

Water Distribution ◽

Average Rate ◽

Extended Period ◽

Distribution Networks ◽

Residual Chlorine ◽

Variable Speed ◽

Water Age ◽

The Impact

Water quality has become a prominent issue in the study of water distribution networks. Variable speed pumps (VSPs) can control and improve the performance of water distribution systems. However, they may have effects on the water quality. The objective of this study was to investigate the impact of VSPs on water quality. The EPANET water quality simulator was applied for modelling water age and chlorine residual in a distribution network. In addition, intrusion of an active contaminant and analysis of leakage effects on residual chlorine concentration were performed through extended period simulations. Results indicate that VSPs may have negative impacts on water quality, including increased water age during low consumption times, and reduced disinfectant residuals at peak hours. In addition, the average rate of chlorine decay for fixed speed pumps (57%) is higher than that for VSPs (54%) when a conservative contaminant (sewage water) is considered.

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Reliability of water distribution networks due to pumps failure: comparison of VSP and SSP application

Drinking Water Engineering and Science Discussions ◽

10.5194/dwesd-5-351-2012 ◽

2012 ◽

Vol 5 (1) ◽

pp. 351-373 ◽

Cited By ~ 3

Author(s):

N. Mehzad ◽

M. Tabesh ◽

S. S. Hashemi ◽

B. Ataee Kia

Keyword(s):

Water Distribution ◽

Computer Code ◽

Distribution Networks ◽

Visual Basic ◽

Water Distribution Networks ◽

Variable Speed ◽

Active Components ◽

Important Indicator ◽

Pumping Stations ◽

The City

<p><strong>Abstract.</strong> Reliability is an important indicator to ensure the operation of Water Distribution Networks (WDNs). To optimize the operation of WDN, it is necessary to incorporate the reliability of active components (such as pumps and tanks) besides the reliability of pipes. In this research, a concept is suggested to calculate the reliability of WDNs' pumping stations. A computer code is provided in Visual Basic and is linked to EPANET2.0. To evaluate the proposed methodology a real WDN near the city of Tehran is considered. According to the obtained results, it is concluded that by increasing the demand of the WDN during a day, the reliability of pumps decrease. Therefore, it seems that decision-making is necessary if high demand hours are considered, in order to increase the reliability of the system. On the other hand, it is observed in this research that using variable speed pumps not only reduces the energy cost of the network, but also the reliability of the pumping stations with variable speed pumps is higher than single speed pumps. Therefore, using VSP is highly recommended in WDNs.</p>

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Optimizing Water Age and Pressure in Drinking Water Distribution Networks

Environmental Sciences Proceedings ◽

10.3390/environsciproc2020002051 ◽

2020 ◽

Vol 2 (1) ◽

pp. 51

Author(s):

Nikolaos Kourbasis ◽

Menelaos Patelis ◽

Stavroula Tsitsifli ◽

Vasilis Kanakoudis

Keyword(s):

Water Distribution ◽

Water Pressure ◽

Distribution Network ◽

Water Distribution Network ◽

Distribution Networks ◽

Water Distribution Networks ◽

Operating Pressure ◽

Water Age ◽

Water Losses ◽

Simulation And Optimization

Water distribution networks suffer from high levels of water losses due to leaks and breaks, mainly due to high operating pressure. One of the most well-known methods to reduce water losses is pressure management. However, when the operating pressure in a water distribution network reduces, the time the water stays within the network (called water age) increases. Increased water age means deteriorated water quality. In this paper, water pressure in relation to water age is addressed in a water distribution network in Greece. Using simulation and optimization tools, the optimum solution is found to reduce water age and operating pressure at the same time. In addition, District Metered Areas are formed and water age is optimized.

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