scholarly journals Analytical and experimental investigation of chlorine decay in water supply systems under unsteady hydraulic conditions

2013 ◽  
Vol 16 (3) ◽  
pp. 690-709 ◽  
Author(s):  
Angeliki Aisopou ◽  
Ivan Stoianov ◽  
Nigel Graham ◽  
Bryan Karney
Keyword(s):  
Water Quality ◽  
Shear Stress ◽  
Water Supply ◽  
Rate Of Change ◽  
Water Supply Systems ◽  
Unsteady State ◽  
Hydraulic Conditions ◽  
Chlorine Decay ◽  
The Impact ◽  
Supply Systems

This paper investigates the impact of the dynamic hydraulic conditions on the kinetics of chlorine decay in water supply systems. A simulation framework has been developed for the scale-adaptive hydraulic and chlorine decay modelling under steady- and unsteady-state flows. An unsteady decay coefficient is defined which depends upon the absolute value of shear stress and the rate of change of shear stress for quasi-unsteady and unsteady-state flows. By coupling novel instrumentation technologies for continuous hydraulic monitoring and water quality sensors for in-pipe water quality sensing a pioneering experimental and analytical investigation was carried out in a water transmission main. The results were used to model monochloramine decay and these demonstrate that the dynamic hydraulic conditions have a significant impact on water quality deterioration. The spatial and temporal resolution of experimental data provides new insights for the near real-time modelling and management of water quality as well as highlighting the uncertainty and challenges of accurately modelling the loss of disinfectant in water supply networks.

scholarly journals Managing Water Quality in Intermittent Supply Systems: The Case of Mukono Town, Uganda

Water ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 806
Author(s):  
Takuya Sakomoto ◽  
Mahmood Lutaaya ◽  
Edo Abraham
Keyword(s):  
Water Quality ◽  
Water Supply ◽  
Health Hazard ◽  
Water Quality Monitoring ◽  
Economic Feasibility ◽  
Water Supply Systems ◽  
Chemical Contamination ◽  
Intermittent Water Supply ◽  
The Impact ◽  
Supply Systems

Intermittent water supply networks risk microbial and chemical contamination through multiple mechanisms. In particular, in the cities of developing countries, where intrusion through leaky pipes are more prevalent and the sanitation systems coverage is low, contaminated water can be a public health hazard. Although countries using intermittent water supply systems aim to change to continuous water supply systems—for example, Kampala city is targeting to change to continuous water supply by 2025 through an expansion and rehabilitation of the pipe infrastructure—it is unlikely that this transition will happen soon because of rapid urbanisation and economic feasibility challenges. Therefore, water utilities need to find ways to supply safe drinking water using existing systems until gradually changing to a continuous supply system. This study describes solutions for improving water quality in Mukono town in Uganda through a combination of water quality monitoring (e.g., identifying potential intrusion hotspots into the pipeline using field measurements) and interventions (e.g., booster chlorination). In addition to measuring and analyses of multiple chemical and microbial water quality parameters, we used EPANET 2.0 to simulate the water quality dynamics in the transport pipeline to assess the impact of interventions.

scholarly journals Network Model Analysis of Residual Chlorine to Reduce Disinfection Byproducts in Water Supply Systems in Yangon City, Myanmar

Water ◽  
2021 ◽  
Vol 13 (20) ◽  
pp. 2921
Author(s):  
Nwe Nwe Zin ◽  
Shinobu Kazama ◽  
Satoshi Takizawa
Keyword(s):  
Water Quality ◽  
Water Supply ◽  
Tap Water ◽  
Water Quality Monitoring ◽  
Disinfection Byproducts ◽  
Residual Chlorine ◽  
Water Supply Systems ◽  
Formation Kinetics ◽  
Chlorine Decay ◽  
Supply Systems

In Yangon City, chlorination commenced in January 2020 to supply drinkable water; therefore, there is as yet no information on chlorine decay and DBP formation in the water supply system. This study aimed to find methods to optimize chlorine dosage in Yangon City. Onsite sampling and laboratory analyses of residual chlorine and trihalomethane (THM) formation, as well as water quality simulations, were conducted to find the chlorine decay and THM formation kinetics. Due to a high chlorine dose of 2 mg/L for both pre- and post-chlorination, disinfection was effective despite the low removal efficiency of turbidity. However, THMs were found in high levels in both treated and tap water due to the high THM formation potential of raw water. The re-contamination and/or transformation of dissolved organic matter were found in the distribution network by increases in specific ultraviolet absorption (SUVA) values and excitation-emission matrix (EEM) fluorophores, which brought about variations of THMs in the networks. The EPANET models were run assuming there to be no water leakages; it was found that the chlorine dose could be decreased to 0.8 mg/L to meet the guidelines for THMs and residual chlorine. The methods employed in this study could be also applied in other water supply systems in tropical developing countries with limited water quality monitoring data.

Methodological Approaches to Organization of Drinking Water Quality Monitoring Programs

2020 ◽  
pp. 4-8
Author(s):  
Yu.A. Novikova ◽  
I.O. Myasnikov ◽  
A.A. Kovshov ◽  
N.A. Tikhonova ◽  
N.S. Bashketova
Keyword(s):  
Water Quality ◽  
Drinking Water ◽  
Water Supply ◽  
Cold Water ◽  
Water Quality Monitoring ◽  
Drinking Water Quality ◽  
Quality Monitoring ◽  
Water Supply Systems ◽  
Monitoring Programs ◽  
Supply Systems

Summary. Introduction: Drinking water is one of the most important environmental factors sustaining life and determining human health. The goal of the Russian Federal Clean Water Project is to improve drinking water quality through upgrading of water treatment and supply systems using advanced technologies, including those developed by the military-industrial complex. The most informative and reliable sources of information for assessing drinking water quality are the results of systematic laboratory testing obtained within the framework of socio-hygienic monitoring (SGM) and production control carried out by water supply organizations. The objective of our study was to formulate approaches to organizing quality monitoring programs for centralized cold water supply systems. Materials and methods: We reviewed programs and results of drinking water quality laboratory tests performed by Rospotrebnadzor bodies and institutions within the framework of SGM in 2017–2018. Results: We established that drinking water quality monitoring in the constituent entities of the Russian Federation differs significantly in the number of monitoring points (566 in the Krasnoyarsk Krai vs 10 in Sevastopol) and measured indicators, especially sanitary and chemical ones (53 inorganic and organic substances in the Kemerovo Region vs one indicator in the Amur Region). Discussion: For a more complete and objective assessment of drinking water quality in centralized cold water supply systems, monitoring points should be organized at all stages of water supply with account for the coverage of the maximum number of people supplied with water from a particular network. Thus, the number of points in the distribution network should depend, inter alia, on the size of population served. In urban settlements with up to 10,000 inhabitants, for example, at least 4 points should be organized while in the cities with more than 3,000,000 inhabitants at least 80 points are necessary. We developed minimum mandatory lists of indicators and approaches to selecting priority indices to be monitored at all stages of drinking water supply.

Better water quality and higher energy efficiency by using model predictive flow control at water supply systems

2013 ◽  
Vol 62 (1) ◽  
pp. 1-13 ◽  
Author(s):  
M. Bakker ◽  
J. H. G. Vreeburg ◽  
L. J. Palmen ◽  
V. Sperber ◽  
G. Bakker ◽  
...  
Keyword(s):  
Water Quality ◽  
Energy Efficiency ◽  
Water Supply ◽  
Flow Control ◽  
Water Supply Systems ◽  
Supply Systems

Checking The Hydraulic Efficiency and Improving Safety of the Internal Water Supply 

2018 ◽  
Vol 20 (2) ◽  
pp. 121-125
Author(s):  
Sarka Krocova ◽  
Karla Barcova
Keyword(s):  
Water Supply ◽  
Water Supply Systems ◽  
Safety Hazard ◽  
Industrial Facilities ◽  
Internal Water ◽  
Operational Capabilities ◽  
Wide Range ◽  
Hydraulic Conditions ◽  
Industrial Zones ◽  
Supply Systems

Water management systems in industrial facilities, industrial zones, hospitals and other internal water systems relatively frequently fail to meet the intended purpose for which they were built when an extraordinary event occurs. They may even pose a safety hazard. The causes of this condition may be of internal or external origin. Given that internal water supply systems of large premises always have a multipurpose character, i.e. to provide enough drinking water for drinking and sanitation purposes and also as a source of fire water for the fire safety of buildings, they must meet a wide range of hydraulic conditions and technical-operational capabilities. By what means and methods it is possible to achieve the desired state in economically-acceptable dimensions, while maintaining all the necessary hydraulic capabilities of the supply points of drinking and fire water, is briefly described in this article.

scholarly journals Improving of the quality and reliability of water supply systems on the basis of modern information and computing technologies

2018 ◽  
Vol 39 ◽  
pp. 04003 ◽  
Author(s):  
Aleksandr V. Alekseev
Keyword(s):  
Water Supply ◽  
Operational Reliability ◽  
Operating Conditions ◽  
Mode Analysis ◽  
Water Supply Systems ◽  
Common Information ◽  
Quality Of Water ◽  
Common Information Space ◽  
Hydraulic Conditions ◽  
Supply Systems

The article deals with the issues of increasing the reliability and quality of water supply systems operation on the basis of modern methods and software complexes for the analysis and development of hydraulic conditions. Against the backdrop of the analysis of the literature on the problem of reliability, the relevance and insufficiency of attention to maintaining the required level of reliability at the stage of water supply systems operation are revealed. The main factors that affect on operational reliability are considered. These factors are largely associated with the competent organization of operating conditions of water supply systems. A brief description of the «Angara-WS» computer program for solving the problems of analyzing and developing of hydraulic conditions, as well as the experience of its practical application, is given. A special feature of this complex is its universality, the possibility of multilevel representation of models, the execution of one-and multi-level calculations, integration into a common information space of the enterprise, automation of the processes of mode analysis, accumulation and analysis of damage statistics.

scholarly journals Circuit Rider post-construction support: improvements in domestic water quality and system sustainability in El Salvador

2014 ◽  
Vol 4 (3) ◽  
pp. 460-470 ◽  
Author(s):  
Georgia L. Kayser ◽  
William Moomaw ◽  
Jose Miguel Orellana Portillo ◽  
Jeffrey K. Griffiths
Keyword(s):  
Water Quality ◽  
Water Supply ◽  
El Salvador ◽  
Low Cost ◽  
Water Supply Systems ◽  
Domestic Water ◽  
Piped Water ◽  
Comparable Control ◽  
System Sustainability ◽  
The Impact

Small piped water supply systems are often unable to provide reliable, microbiologically safe, and sustainable service over time, and this has direct impacts on public health. Circuit Rider (CR) post-construction support (PCS) addresses this through the provision of technical, financial, and operational assistance to these systems. CRPCS operates in low and high-income countries; yet, no rigorous studies of CRPCS exist. We measured the impact of CRPCS on ‘water quality’ and ‘sustainability’ indicators (technical and administrative capacity, and water supply protection) in El Salvador. In this field-based study, a case-control design was utilized in 60 randomly selected case (28 CR) and comparable control (32 noCR) communities. Microbiological water quality tests and pre-tested structured key-informant interviews were conducted. The operational costs of CRPCS were also assessed. Data were compared using parametric and non-parametric statistical methods. We found communities with CRPCS had significantly lower microbiological water contamination, better disinfection rates, higher water fee payment rates, greater transparency (measured by auditable banking records), greater rates of household metering, and higher spending for repairs and water treatment than comparable control communities. CRPCS is also a low-cost (<$1 per household/year in El Salvador) drinking water intervention.

Sign in / Sign up

Export Citation Format

Share Document