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Wannapop R, Jearsiripongkul T, Jiamjiroch K. Adaptive urban drinking water supply model using the effect of node elevation and head loss formula: A case study. Heliyon 2024; 10:e26181. [PMID: 38434303 PMCID: PMC10907531 DOI: 10.1016/j.heliyon.2024.e26181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Revised: 11/22/2023] [Accepted: 02/08/2024] [Indexed: 03/05/2024] Open
Abstract
Along with population growth and health improvement, water demand due to urbanization is increasing and creating a need to develop a strategy for handling water supply networks (WSNs). In the last decade, software modeling of WSNs has been developed to evaluate the state of networks in terms of pressure control, leakage analysis, and overall demand determination. In the case of very complex and extremely large networks, it is very difficult to manage the water supply. Metropolitan Waterworks Authority (MWA) in Thailand has to supply drinking water to the three densely populated cities; Bangkok, Nonthaburi, and Samut Prakan, that cover an area of 2944.05 km2. Hence, MWA has developed a main pipe model using EPANET software as a managing tool. This tool can offer a good solution for the water supply, but there is approximately a 14 percent error, mainly due to not having the elevation data of the pipe network. The current research is based on demand and pressure modeling analysis with utilizing two important parameters, node elevations, and head loss. The first trial model was an initial revision of the node elevation based on a road surface map. It was found that the model with elevation data could offer a better solution and was 3.95% more accurate than the existing model. The result was significantly improved, but another error, which may have been caused by using an inappropriate head loss model, was found. As the introduced model is based on the Hazen-William model, it cannot offer an accurate solution for all Reynolds number ranges. Even though Darcy-Weisbach is more complex to use, it could provide a better solution. The results indicate the Darcy-Weisbach model produces results that are 8.65% more accurate than the Hazen-William model.
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Affiliation(s)
- Rangsan Wannapop
- Department of Mechanical Engineering, Thammasat School of Engineering, Thammasat University, Thailand
| | - Thira Jearsiripongkul
- Department of Mechanical Engineering, Thammasat School of Engineering, Thammasat University, Thailand
| | - Krit Jiamjiroch
- Department of Mechanical Engineering, Thammasat School of Engineering, Thammasat University, Thailand
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2
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Kalu CM, Mudau KL, Masindi V, Ijoma GN, Tekere M. Occurrences and implications of pathogenic and antibiotic-resistant bacteria in different stages of drinking water treatment plants and distribution systems. Heliyon 2024; 10:e26380. [PMID: 38434035 PMCID: PMC10906316 DOI: 10.1016/j.heliyon.2024.e26380] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2023] [Revised: 12/05/2023] [Accepted: 02/12/2024] [Indexed: 03/05/2024] Open
Abstract
Different stages of drinking water treatment plants (DWTPs) play specific roles in diverse contaminants' removal present in natural water sources. Although the stages are recorded to promote adequate treatment of water, the occurrence of pathogenic bacteria (PB) and antibiotic-resistant bacteria (ARB) in the treated water and the changes in their diversity and abundance as it passed down to the end users through the drinking water distribution systems (DWDSs), is a great concern, especially to human health. This could imply that the different stages and the distribution system provide a good microenvironment for their growth. Hence, it becomes pertinent to constantly monitor and document the diversity of PB and ARB present at each stage of the treatment and distribution system. This review aimed at documenting the occurrence of PB and ARB at different stages of treatment and distribution systems as well as the implication of their occurrence globally. An exhaustive literature search from Web of Science, Science-Direct database, Google Scholar, Academic Research Databases like the National Center for Biotechnology Information, Scopus, and SpringerLink was done. The obtained information showed that the different treatment stages and distribution systems influence the PB and ARB that proliferate. To minimize the human health risks associated with the occurrence of these PB, the present review, suggests the development of advanced technologies that can promote quick monitoring of PB/ARB at each treatment stage and distribution system as well as reduction of the cost of environomics analysis to promote better microbial analysis.
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Affiliation(s)
- Chimdi M. Kalu
- Department of Environmental Science, College of Agriculture and Environmental Sciences, University of South Africa, Florida, 1710, South Africa
| | - Khuthadzo L. Mudau
- Department of Environmental Science, College of Agriculture and Environmental Sciences, University of South Africa, Florida, 1710, South Africa
| | - Vhahangwele Masindi
- Department of Environmental Science, College of Agriculture and Environmental Sciences, University of South Africa, Florida, 1710, South Africa
- Magalies Water, Scientific Services, Research & Development Division, Brits, South Africa
| | - Grace N. Ijoma
- Department of Environmental Science, College of Agriculture and Environmental Sciences, University of South Africa, Florida, 1710, South Africa
| | - Memory Tekere
- Department of Environmental Science, College of Agriculture and Environmental Sciences, University of South Africa, Florida, 1710, South Africa
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3
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Zhao B, Liu R, Li Y, Xu H, Li X, Gu J, Zhang X, Wang Y, Wang Y. Changes of putative pathogenic species within the water bacterial community in large-scale drinking water treatment and distribution systems. Water Res 2024; 249:120947. [PMID: 38043356 DOI: 10.1016/j.watres.2023.120947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Revised: 11/23/2023] [Accepted: 11/29/2023] [Indexed: 12/05/2023]
Abstract
Although the management of microbes in drinking water is of paramount importance for public health, there remain challenges in comprehensively examining pathogenic bacteria in the water supply system at the species level. In this study, high-throughput sequencing of nearly full-length 16S rRNA genes was performed to investigate the changes of the water bacterial community in three large-scale drinking water treatment plants (DWTPs) and their corresponding distribution systems during winter and summer. Our findings revealed significant differences in the bacterial community structure between winter and summer water samples for each DWTP and its distribution management area (DMA). In the groundwater-fed DWTP, selective enrichment of mycobacterial species was observed in both seasons, and the subsequent DMA also exhibited strong selection for specific mycobacterial species. In one of the surface water-fed DWTPs, certain Legionella species present in the source water in winter were selectively enriched in the bacterial community after pre-oxidation, although they were susceptible to the subsequent purification steps. A variety of putative pathogenic species (n = 83) were identified based on our pathogen identification pipeline, with the dominant species representing opportunistic pathogens commonly found in water supply systems. While pathogen removal primarily occurred during the purification processes of DWTPs, especially for surface water-fed plants, the relative abundance of pathogenic bacteria in the DMA water flora was lower than that in the DWTP effluent flora, indicating a diminished competitiveness of pathogens within the DMA ecosystem.
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Affiliation(s)
- Bei Zhao
- Beijing Waterworks Group Co., Ltd, Beijing, PR China; Beijing Engineering Research Center for Drinking Water Quality, Beijing, PR China
| | - Ruyin Liu
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, PR China; Weiqiao-UCAS Science and Technology Park, Binzhou Institute of Technology, Binzhou, Shandong, PR China.
| | - Yuxian Li
- Beijing Waterworks Group Co., Ltd, Beijing, PR China; Beijing Engineering Research Center for Drinking Water Quality, Beijing, PR China
| | - Hao Xu
- Beijing Waterworks Group Co., Ltd, Beijing, PR China; Beijing Engineering Research Center for Drinking Water Quality, Beijing, PR China
| | - Xiangyi Li
- Beijing Waterworks Group Co., Ltd, Beijing, PR China; Beijing Engineering Research Center for Drinking Water Quality, Beijing, PR China
| | - Junnong Gu
- Beijing Waterworks Group Co., Ltd, Beijing, PR China; Beijing Engineering Research Center for Drinking Water Quality, Beijing, PR China
| | - Xiaolan Zhang
- Beijing Waterworks Group Co., Ltd, Beijing, PR China; Beijing Engineering Research Center for Drinking Water Quality, Beijing, PR China
| | - Yue Wang
- Beijing Waterworks Group Co., Ltd, Beijing, PR China
| | - Yansong Wang
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, PR China
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4
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Hammodat AR, Nassar S, Mortula MM, Shamsuzzaman M. Factors affecting the leaching of micro and nanoplastics in the water distribution system. J Environ Manage 2023; 345:118779. [PMID: 37586171 DOI: 10.1016/j.jenvman.2023.118779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2023] [Revised: 07/27/2023] [Accepted: 08/09/2023] [Indexed: 08/18/2023]
Abstract
The role of the water distribution system (WDS) requires that it supply water of sufficient quality to households. Unregulated leaching of micro and nanoplastics from plastic pipes of the distribution system is therefore a cause for concern, particularly with the rise in research associating these plastic particles to adverse health impacts in living organisms. Within this study, four parameters (pH, free chlorine concentration, pipe material, and time) were varied in a pipe loop network to observe their effect on microplastic (MP) and nanoplastic (NP) leaching into the simulated distribution network. Results indicated an abundance of MPs/NPs in different shapes and sizes throughout the samples. Graphical trends illustrated that basic pH values contributed to a higher number of particles. Statistical analysis via analysis of variance (ANOVA) confirmed this observation and further showed interaction of chlorine dose and pH concentration (p-value = 0.000), and chlorine dose and pipe material (p-value = 0.038) was also significant to leaching. Numerically, polyethylene (PE) particles were the most abundant with a total of 15194 particles, followed by 12920 polypropylene random copolymer (PPR) particles and 12317 polyvinyl chloride (PVC) particles. It was also noticed that the number of particles decreased with time.© 2023 Elsevier Inc. All rights reserved.
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Affiliation(s)
- Amina Rayan Hammodat
- American University of Sharjah, University City, 26666, Sharjah, United Arab Emirates
| | - Shumayal Nassar
- American University of Sharjah, University City, 26666, Sharjah, United Arab Emirates
| | - Md Maruf Mortula
- American University of Sharjah, University City, 26666, Sharjah, United Arab Emirates.
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5
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Zhang Q, Yang J, Zhang W, Kumar M, Liu J, Liu J, Li X. Deep fuzzy mapping nonparametric model for real-time demand estimation in water distribution systems: A new perspective. Water Res 2023; 241:120145. [PMID: 37270943 DOI: 10.1016/j.watres.2023.120145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 04/06/2023] [Accepted: 05/28/2023] [Indexed: 06/06/2023]
Abstract
Hydraulic modeling has been recognized as a valuable tool for improving the design, operation, and management of water distribution systems (WDSs) as it allows engineers to simulate and analyze behaviors of WDSs in real time and help them make scientific decisions. The informatization of urban infrastructure has motivated the real-time fine-grained control of WDSs, making it one of the hotspots in recent years, thereby putting higher requirements on WDS online calibration in terms of efficiency and accuracy, especially when dealing with large-complex WDSs. To achieve this purpose, this paper proposes a novel approach (i.e., deep fuzzy mapping nonparametric model (DFM)) from a new perspective for developing a real-time WDS model. To our knowledge, this is the first work that considers uncertainties in modeling problems using fuzzy membership functions and establishes the precise inverse mapping from pressure/flow sensors to nodal water consumption for a given WDS based on the proposed DFM framework. Unlike most traditional calibration methods that require time to optimize model parameters, the DFM approach has a unique analytical solution derived through rigorous mathematical theory, thus the DFM is computationally fast as a result of sensibly handling the problems whose solutions typically require iterative numerical algorithms and large computational time. The proposed method is applied to two case studies and the results obtained show that it can produce a real-time estimation of nodal water consumption with higher accuracy, computational efficiency, and robustness relative to traditional calibration methods.
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Affiliation(s)
- Qingzhou Zhang
- Key Laboratory of Green Construction and Intelligent Maintenance for Civil Engineering of Hebei Province, Hebei Province Low-Carbon and Clean Building Heating Technology Innovation Center, Yanshan University, Qinhuangdao 066004, China
| | - Jingzhi Yang
- Institute of Translational Medicine, Shanghai University, Shanghai 200444, China
| | - Weiping Zhang
- School of Software, Northwestern Polytechnical University, Taicang 215400, China.
| | - Mohit Kumar
- Faculty of Computer Science and Electrical Engineering, University of Rostock, Germany
| | - Jun Liu
- Key Laboratory of Green Construction and Intelligent Maintenance for Civil Engineering of Hebei Province, Hebei Province Low-Carbon and Clean Building Heating Technology Innovation Center, Yanshan University, Qinhuangdao 066004, China
| | - Jingqing Liu
- College of Civil Engineering and Architecture, Zhejiang University, Zhejiang, China
| | - Xiujuan Li
- College of Civil Engineering and Architecture, Zhejiang University, Zhejiang, China
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6
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Lee J, Nam SH, Koo JW, Shin Y, Kim E, Hwang TM. Fluorescence excitation-emission matrix spectroscopy coupled with parallel factor analysis to determine chlorine decay constants in urban water distribution system. Chemosphere 2023; 331:138733. [PMID: 37105307 DOI: 10.1016/j.chemosphere.2023.138733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 04/08/2023] [Accepted: 04/18/2023] [Indexed: 05/09/2023]
Abstract
This study applied a method for estimating chlorine decay constant (k) in urban water distribution systems using fluorescence excitation-emission matrix spectroscopy-parallel factor analysis (FEEM-PARAFAC), considering that it accounts for the influence of organic matter in the target area. The simultaneous impacts of seasonal variations on chlorine consumption and dissolved organic matter (DOM) composition were investigated for a year in three full-scale water distribution systems in I city (areas S, K, and G). Bulk decay constants (kb) were obtained through bottle tests, and the kb value was observed to differ by season and significantly affected by temperature. It exhibited its highest value, 0.794 d-1, in summer at area G. As a result of analyses through F-EEM-PARAFAC, it was determined that the components of the target raw water were humic-like and tryptophan-like. The quantitative analysis of organic substances through PARAFAC revealed that area G had the highest score (C1+C2) than other areas. 11.568, 10.578, and 11.771 in summer at areas S, K, and G, respectively. The model equations were derived such that the significant (R2 = 0.85-0.95) correlation between the C1 and C2 model scores and total chlorine decay constants (kt) verified via PARAFAC analysis of the target raw water was considered. Furthermore, a method for obtaining the wall decay constants at a target point based on the correlation equation was investigated.
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Affiliation(s)
- Juwon Lee
- Korea Institute of Civil Engineering and Building Technology, 283 Goyangdar-Ro, Ilsan-Gu, Goyang-Si, Gyeonggi-Do, 411-712, Republic of Korea; Korea University of Science & Technology, 217 Gajung-ro Yuseong-gu, Daejeon, 305-333, Republic of Korea
| | - Sook-Hyun Nam
- Korea Institute of Civil Engineering and Building Technology, 283 Goyangdar-Ro, Ilsan-Gu, Goyang-Si, Gyeonggi-Do, 411-712, Republic of Korea
| | - Jae-Wuk Koo
- Korea Institute of Civil Engineering and Building Technology, 283 Goyangdar-Ro, Ilsan-Gu, Goyang-Si, Gyeonggi-Do, 411-712, Republic of Korea
| | - Yonghyun Shin
- Korea Institute of Civil Engineering and Building Technology, 283 Goyangdar-Ro, Ilsan-Gu, Goyang-Si, Gyeonggi-Do, 411-712, Republic of Korea
| | - Eunju Kim
- Korea Institute of Civil Engineering and Building Technology, 283 Goyangdar-Ro, Ilsan-Gu, Goyang-Si, Gyeonggi-Do, 411-712, Republic of Korea
| | - Tae-Mun Hwang
- Korea Institute of Civil Engineering and Building Technology, 283 Goyangdar-Ro, Ilsan-Gu, Goyang-Si, Gyeonggi-Do, 411-712, Republic of Korea; Korea University of Science & Technology, 217 Gajung-ro Yuseong-gu, Daejeon, 305-333, Republic of Korea.
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7
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Li Z, Liu H, Zhang C, Fu G. Generative adversarial networks for detecting contamination events in water distribution systems using multi-parameter, multi-site water quality monitoring. Environ Sci Ecotechnol 2023; 14:100231. [PMID: 36578363 PMCID: PMC9791317 DOI: 10.1016/j.ese.2022.100231] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 12/06/2022] [Accepted: 12/06/2022] [Indexed: 06/17/2023]
Abstract
Contamination events in water distribution networks (WDNs) can have a huge impact on water supply and public health; increasingly, online water quality sensors are deployed for real-time detection of contamination events. Machine learning has been used to integrate multivariate time series water quality data at multiple stations for contamination detection; however, accurate extraction of spatial features in water quality signals remains challenging. This study proposed a contamination detection method based on generative adversarial networks (GANs). The GAN model was constructed to simultaneously consider the spatial correlation between sensor locations and temporal information of water quality indicators. The model consists of two networks-a generator and a discriminator-the outputs of which are used to measure the degree of abnormality of water quality data at each time step, referred to as the anomaly score. Bayesian sequential analysis is used to update the likelihood of event occurrence based on the anomaly scores. Alarms are then generated from the fusion of single-site and multi-site models. The proposed method was tested on a WDN for various contamination events with different characteristics. Results showed high detection performance by the proposed GAN method compared with the minimum volume ellipsoid benchmark method for various contamination amplitudes. Additionally, the GAN method achieved high accuracy for various contamination events with different amplitudes and numbers of anomalous water quality parameters, and water quality data from different sensor stations, highlighting its robustness and potential for practical application to real-time contamination events.
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Affiliation(s)
- Zilin Li
- School of Hydraulic Engineering, Dalian University of Technology, Dalian, Liaoning, 116024, China
- Centre for Water Systems, University of Exeter, Exeter, EX4 4QF, UK
| | - Haixing Liu
- School of Hydraulic Engineering, Dalian University of Technology, Dalian, Liaoning, 116024, China
| | - Chi Zhang
- School of Hydraulic Engineering, Dalian University of Technology, Dalian, Liaoning, 116024, China
| | - Guangtao Fu
- Centre for Water Systems, University of Exeter, Exeter, EX4 4QF, UK
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8
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Dong F, Zhu J, Li J, Fu C, He G, Lin Q, Li C, Song S. The occurrence, formation and transformation of disinfection byproducts in the water distribution system: A review. Sci Total Environ 2023; 867:161497. [PMID: 36634528 DOI: 10.1016/j.scitotenv.2023.161497] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 01/02/2023] [Accepted: 01/05/2023] [Indexed: 06/17/2023]
Abstract
Disinfection is an effective process to inactivate pathogens in drinking water treatment. However, disinfection byproducts (DBPs) will inevitably form and may cause severe health concerns. Previous research has mainly focused on DBPs formation during the disinfection in water treatment plants. But few studies paid attention to the formation and transformation of DBPs in the water distribution system (WDS). The complex environment in WDS will affect the reaction between residual chlorine and organic matter to form new DBPs. This paper provides an overall review of DBPs formation and transformation in the WDS. Firstly, the occurrence of DBPs in the WDS around the world was cataloged. Secondly, the primary factors affecting the formation of DBPs in WDS have also been summarized, including secondary chlorination, pipe materials, biofilm, deposits and coexisting anions. Secondary chlorination and biofilm increased the concentration of regular DBPs (e.g., trihalomethanes (THMs) and haloacetic acids (HAAs)) in the WDS, while Br- and I- increased the formation of brominated DBPs (Br-DBPs) and iodinated DBPs (I-DBPs), respectively. The mechanism of DBPs formation and transformation in the WDS was systematically described. Aromatic DBPs could be directly or indirectly converted to aliphatic DBPs, including ring opening, side chain breaking, chlorination, etc. Finally, the toxicity of drinking water in the WDS caused by DBPs transformation was examined. This review is conducive to improving the knowledge gap about DBPs formation and transformation in WDS to better solve water supply security problems in the future.
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Affiliation(s)
- Feilong Dong
- College of Environment, Zhejiang University of Technology, Hangzhou 310014, China
| | - Jiani Zhu
- College of Environment, Zhejiang University of Technology, Hangzhou 310014, China
| | - Jinzhe Li
- College of Environment, Zhejiang University of Technology, Hangzhou 310014, China
| | - Chuyun Fu
- College of Environment, Zhejiang University of Technology, Hangzhou 310014, China
| | - Guilin He
- School of Municipal and Environmental Engineering, Shandong Jianzhu University, Jinan 250101, China
| | - Qiufeng Lin
- Department of Earth and Environmental Studies, Montclair State University, Montclair, NJ 07043, United States
| | - Cong Li
- School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai 200433, China
| | - Shuang Song
- College of Environment, Zhejiang University of Technology, Hangzhou 310014, China.
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9
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Liao P, Zhang T, Fang L, Jiang R, Wu G. Chlorine decay and disinfection by-products transformation under booster chlorination conditions: A pilot-scale study. Sci Total Environ 2022; 851:158115. [PMID: 35985588 DOI: 10.1016/j.scitotenv.2022.158115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Revised: 08/14/2022] [Accepted: 08/15/2022] [Indexed: 06/15/2023]
Abstract
Booster chlorination was usually employed in water distribution systems with a long hydraulic retention time. The free chlorine decay and disinfection by-products (DBPs) transformation under booster chlorination conditions were investigated within a pilot-scale water distribution system (WDS). Compared with the initial chlorination in water plants, the loss of chlorine was relatively slow and could be described with first-order kinetic model. The rate of chlorine decay and the generation of DBPs in WDS were much greater than those in beaker. High flow rate and the hydraulic transients both promoted chlorine decay and DBPs formation, especially for dichloroacetonitrile (DCAN). The formation of trihalomethanes (THMs) and haloacetic acids (HAAs) was higher in the ductile iron pipe than in the steel pipe. After booster chlorination, THMs, HAAs, and DCAN all climbed up and then declined continuously, but the peak times were different during the reaction process. The results showed the generation period of DBPs followed the order: THMs (27 h) > HAAs (22 h) > DCAN (5 h). DCAN was not stable in WDS and could be decomposed for a long hydraulic retention time (HRT). The decrease of dichloroacetic acid (DCAA) and increase of trichloroacetic acid (TCAA) indicated that DCAA may turn into TCAA. Linear relationships between the free chlorine demand (FCD) and the generation of THMs that considered both buck water and the pipe wall, as well as the different hydraulic conditions, were established to predict the formation of DBPs in WDS after booster chlorination.
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Affiliation(s)
- Pubin Liao
- College of Civil Engineering and Architecture, Zhejiang University, Key Laboratory of Drinking Water Safety and Distribution Technology of Zhejiang Province, Hangzhou 310058, PR China.
| | - Tuqiao Zhang
- College of Civil Engineering and Architecture, Zhejiang University, Key Laboratory of Drinking Water Safety and Distribution Technology of Zhejiang Province, Hangzhou 310058, PR China.
| | - Lei Fang
- College of Civil Engineering and Architecture, Zhejiang University, Key Laboratory of Drinking Water Safety and Distribution Technology of Zhejiang Province, Hangzhou 310058, PR China.
| | - Rongrong Jiang
- College of Civil Engineering and Architecture, Zhejiang University, Key Laboratory of Drinking Water Safety and Distribution Technology of Zhejiang Province, Hangzhou 310058, PR China.
| | - Guojian Wu
- College of Civil Engineering and Architecture, Zhejiang University, Key Laboratory of Drinking Water Safety and Distribution Technology of Zhejiang Province, Hangzhou 310058, PR China.
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10
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Price E, Abhijith GR, Ostfeld A. Pressure management in water distribution systems through PRVs optimal placement and settings. Water Res 2022; 226:119236. [PMID: 36244147 DOI: 10.1016/j.watres.2022.119236] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Revised: 09/05/2022] [Accepted: 10/08/2022] [Indexed: 06/16/2023]
Abstract
Optimal pressure management is a standard strategy for water loss minimization in water distribution systems (WDS). A pragmatic solution to regulating water pressures and leakage is introducing pressure-reducing valves (PRVs). This paper presents a valve positioning algorithm for optimally deciding the positions and setpoints of PRVs in a WDS. The algorithm derives the hydraulic solution of a WDS as a directed graph, established on the flow directions, using EPANET 2.2 and develops the downstream network supplied by water flowing out of every pipe in the network by applying the depth-first search method. The algorithm later recognizes the pipes leading to the most extended downstream networks, with pressures above the minimum required service pressure, and prioritizes them as the ideal locations for PRV placement. In this way, the proposed algorithm overcomes the limitations of the state-of-the-art in realistically conceptualizing the leakage reduction for optimally positioning the PRVs in WDS. Four studies with varying complexities were selected to demonstrate the algorithm's applicability for deriving pressure management solutions. The solution time for PRV positioning was in seconds for the first three networks and several minutes for the extensive fourth case study. The results corroborate the algorithm's ability to pinpoint the critical nodes with the most increased potential for downstream pressure control and for maintaining the pressure at the least required service pressure level through optimally allocating the PRVs, with acceptable setpoint values, within the pipe network.
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Affiliation(s)
- Eyal Price
- Faculty of Civil and Environmental Engineering, Technion - Israel Institute of Technology, Haifa, Israel
| | - Gopinathan R Abhijith
- Faculty of Civil and Environmental Engineering, Technion - Israel Institute of Technology, Haifa, Israel
| | - Avi Ostfeld
- Faculty of Civil and Environmental Engineering, Technion - Israel Institute of Technology, Haifa, Israel.
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11
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Li Z, Zhang C, Liu H, Zhang C, Zhao M, Gong Q, Fu G. Developing stacking ensemble models for multivariate contamination detection in water distribution systems. Sci Total Environ 2022; 828:154284. [PMID: 35247409 DOI: 10.1016/j.scitotenv.2022.154284] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 02/25/2022] [Accepted: 02/28/2022] [Indexed: 06/14/2023]
Abstract
This study presents a new stacking ensemble model for contamination event detection using multiple water quality parameters. The stacking model consists of a number of machine learning base predictors and a meta-predictor, and it is trained using cross-validation to capture different features in multiple water quality parameters and then used for water quality predictions. For each water quality parameter, the residuals between predicted and measured data are classified to identify anomalies with thresholds derived from the sequential model-based optimization method and detection probabilities updated using Bayesian analysis. Alarms derived from individual water quality parameters are fused to enhance the anomaly signals and improve the detection accuracy. The proposed stacking-based method is evaluated using a data set of six water quality parameters from a real water distribution system with randomly simulated events. The stacking-based method could detect 2496 events out of a total 2500 events without a false alarm. The results show that the stacking method outperforms an artificial neural network (ANN) benchmark method in contamination event detection. The stacking method has a higher true positive rate, lower false positive rate and higher F1 score than the ANN method. This implies that the stacking method has great promise of detecting contamination events in the water distribution system.
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Affiliation(s)
- Zilin Li
- School of Hydraulic Engineering, Dalian University of Technology, Dalian, Liaoning 116024, China
| | - Chi Zhang
- School of Hydraulic Engineering, Dalian University of Technology, Dalian, Liaoning 116024, China.
| | - Haixing Liu
- School of Hydraulic Engineering, Dalian University of Technology, Dalian, Liaoning 116024, China
| | - Chao Zhang
- School of Hydraulic Engineering, Dalian University of Technology, Dalian, Liaoning 116024, China
| | - Mengke Zhao
- School of Hydraulic Engineering, Dalian University of Technology, Dalian, Liaoning 116024, China
| | - Qiang Gong
- Dalian Water Supply Group Co. Ltd., Dalian, Liaoning 116011, China
| | - Guangtao Fu
- Centre for Water Systems, University of Exeter, Exeter EX4 4QF, UK
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12
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Ma B, Seyedi S, Wells E, McCarthy D, Crosbie N, Linden KG. Inactivation of biofilm-bound bacterial cells using irradiation across UVC wavelengths. Water Res 2022; 217:118379. [PMID: 35429876 DOI: 10.1016/j.watres.2022.118379] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2021] [Revised: 02/17/2022] [Accepted: 03/28/2022] [Indexed: 06/14/2023]
Abstract
Opportunistic pathogens (OPs), such as Pseudomonas spp., Legionella spp., and mycobacteria, have been detected in biofilms in drinking water distribution systems and water storage tanks and pose potential risks to finished drinking water quality and safety. Emerging UV technologies, such as UV light emitting diodes (LEDs) and krypton chloride (KrCl*) excimers, could provide an alternative to chemical-based secondary disinfection (i.e., chlorine or chloramines) for controlling biofilm-bound OPs. UV systems offer long lifetimes, ability to select wavelength, small size with high power density, and limited-to-no disinfection by-product formation. In this study, inactivation of biofilm-bound Pseudomonas aeruginosa cells across different maturities was investigated using five UVC devices with different peak emission wavelengths, including a KrCl* excimer (222 nm), a low pressure mercury vapor lamp (254 nm), and three UV LEDs (260 nm, 270 nm, and 282 nm). The UV transmittance and absorbance through the biofilm structure was also documented for the first time using a unique approach. Our results show all UVC devices can inactivate biofilm-bound P. aeruginosa cells up to a point, among which the UV LED with peak emission at 270 nm provided the best disinfection performance. UV sensitivities of biofilm-bound cells decreased with biofilm maturity and while initial rates of inactivation were high, no more than 1.5-2.5 log reduction was possible. Re-suspended biofilm bacteria in aqueous solution were highly sensitive to UV, reaching greater than 6 log reduction. UV shielding by biofilm constituents was observed and was likely one of the reasons for UV resistance but did not fully explain the difference in UV sensitivity between biofilm-bound cells versus planktonic cells. This study improves upon fundamental knowledge and provides guidance for innovative designs using emerging UV technologies for biofilm and pathogen control in water distribution systems.
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Affiliation(s)
- Ben Ma
- Department of Civil, Environmental, and Architectural Engineering, University of Colorado Boulder, 4001 Discovery Dr., Boulder, CO, 80303, United States
| | - Saba Seyedi
- Department of Civil, Environmental, and Architectural Engineering, University of Colorado Boulder, 4001 Discovery Dr., Boulder, CO, 80303, United States
| | - Emma Wells
- Department of Civil, Environmental, and Architectural Engineering, University of Colorado Boulder, 4001 Discovery Dr., Boulder, CO, 80303, United States
| | - David McCarthy
- Department of Civil Engineering, Monash University, Clayton, Vic, 3800, Australia
| | | | - Karl G Linden
- Department of Civil, Environmental, and Architectural Engineering, University of Colorado Boulder, 4001 Discovery Dr., Boulder, CO, 80303, United States.
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13
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Mandel P, Wang Y, Parre A, Féliers C, Heim V. Quality zones automatically identified in water distribution networks by applying data clustering methods to conductivity measurements. Water Res 2021; 207:117716. [PMID: 34818594 DOI: 10.1016/j.watres.2021.117716] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Revised: 09/20/2021] [Accepted: 09/24/2021] [Indexed: 06/13/2023]
Abstract
This paper presents a clustering study showing how conductivity measured every five minutes by 215 probes over four years can be used to determine specific quality zones for a large Water Distribution Network (WDN): 8500 km of pipes, 4.6 M customers. Conductivity time-series are compared using Dynamic Time Warping. Then, probes are ordered using a density-based method, and probe clusters are extracted automatically. The clusters are a sound representation of water quality in the WDN, both in terms of water origin and water residence time. More specifically, zones directly impacted by plants or by external water imports, mixing zones and zones influenced by tanks, can be isolated and analyzed. Globally, 82% of the probes were found to be clustered, consistent with expert knowledge on the WDN operation; 13% were unclassified; 3% were erroneously clustered; and 1% seemed to be reasonably clustered, without any physical understanding yet. Besides providing users with an increased understanding of water quality in WDNs, conductivity-based clusters offer an interesting prior tool for contamination warning systems.
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Affiliation(s)
| | - Yue Wang
- Veolia Eau d'Ile-de-France, 92000 Nanterre, France.
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14
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He G, Zhang T, Zhang Q, Dong F, Wang Y. Characterization of enoxacin (ENO) during ClO 2 disinfection in water distribution system: Kinetics, byproducts, toxicity evaluation and halogenated disinfection byproducts (DBPs) formation potential. Chemosphere 2021; 283:131251. [PMID: 34182641 DOI: 10.1016/j.chemosphere.2021.131251] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 06/11/2021] [Accepted: 06/15/2021] [Indexed: 06/13/2023]
Abstract
Enoxacin (ENO) is widespread in water because it is commonly used as a human and veterinary antibiotic. However, little effort has been dedicated to revealing the transformation mechanisms of ENO destruction using ClO2, especially within a water distribution system (WDS). To address this knowledge gap, the kinetics, byproducts, toxicity, and formation potential of halogenated disinfection byproducts (DBPs) associated with ENO destruction using ClO2 in a pilot-scale PE pipe was explored for the first time. Statistical analyses showed that the destruction efficiency of ENO in the pilot-scale PE pipe was lower than that in deionized water (DI water), and the reactions in DI water followed the second-order kinetic model. Furthermore, pH has a significant effect on the destruction of ENO, and the removal ratio increased at a higher pH. Additionally, increasing the flow rate elevated the ENO removal efficiency; however, the influence of flow velocity was limited to ENO destruction. The ENO removal rates within the diverse pipes exhibited the following order: stainless steel pipe < PE pipe < ductile iron pipe. Nine possible intermediates were identified, and those that were formed by piperazine group cleavage represented the major primary byproducts of the entire destruction process. Additionally, the ENO destruction in a pilot-scale PE pipe had minimal influence on halogenated DBPs and chlorite formation. Finally, the toxicity evaluation illustrated that the presence of ENO increased the potential risk of water quality safety when treated with ClO2.
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Affiliation(s)
- Guilin He
- School of Municipal and Environmental Engineering, Shandong Jianzhu University, Jinan, 250101, China; Resources and Environmental Innovation Institute, Shandong Jianzhu University, Jinan, 250101, China
| | - Tuqiao Zhang
- College of Civil Engineering and Architecture, Zhejiang University, Hangzhou, 310058, China
| | - Qingzhou Zhang
- School of Civil Engineering and Mechanics, Yanshan University, Qinhuangdao, 066004, China
| | - Feilong Dong
- College of Environment, Zhejiang University of Technology, Hangzhou, 310032, China
| | - Yonglei Wang
- School of Municipal and Environmental Engineering, Shandong Jianzhu University, Jinan, 250101, China.
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15
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Sheng D, Zhu S, Zhang W, Bu L, Wu Y, Wang J, Zhou S. Degradation of carbamazepine and disinfection byproducts formation in water distribution system in the presence of copper corrosion products. Chemosphere 2021; 282:131066. [PMID: 34470152 DOI: 10.1016/j.chemosphere.2021.131066] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 05/08/2021] [Accepted: 05/28/2021] [Indexed: 06/13/2023]
Abstract
Copper ion (Cu2+), a common corrosion product released from copper pipes, is widely present in water distribution system (WDS). Cu2+ was confirmed to be capable to catalyze the decay of monochloramine (NH2Cl), which is a commonly used disinfectant and need to maintain a minimum concentration in WDS. Cu2+ and NH2Cl form a system in WDS and their interaction with other substances in WDS is unclear. In this study, the performance of Cu2+/NH2Cl system on degradation of trace pollutants, taking carbamazepine (CBZ) as an example, in WDS was investigated, and significant promotion on CBZ degradation was observed. The acceleration was due to the generation of Cl, OH and other oxidants, which were identified by scavenge experiments. CBZ degradation in Cu2+/NH2Cl system was highly pH-dependent, because the catalytic effect of Cu2+ can only work at low pH (Cu2+ precipitating at pH > 6.0). The removal of CBZ increased with the concentration of Cu2+ increasing. Water matrix (NOM, HCO3- and Br-) can inhibit the removal of CBZ in Cu2+/NH2Cl system. Further, five disinfection byproducts (DBPs), namely, trichloromethane (TCM), dichloroacetonitrile (DCAN), dichloroacetone (DCP), trichloronitromethane (TCNM) and trichloroacetone (TCP), were detected in chloramination in the presence/absence of Cu2+. Compared with chloramination without Cu2+, the cytotoxicity and genotoxicity of formed DBPs increased significantly in the presence of Cu2+, indicating that the chemical safety in WDS deserves more attention.
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Affiliation(s)
- Da Sheng
- Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, Department of Water Engineering and Science, College of Civil Engineering, Hunan University, Changsha, Hunan, 410082, China
| | - Shumin Zhu
- Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, Department of Water Engineering and Science, College of Civil Engineering, Hunan University, Changsha, Hunan, 410082, China.
| | - Wei Zhang
- Hunan Provincial Village Drinking Water Quality Safety Engineering Technology Research Center, Yiyang, 413000, China
| | - Lingjun Bu
- Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, Department of Water Engineering and Science, College of Civil Engineering, Hunan University, Changsha, Hunan, 410082, China
| | - Yangtao Wu
- Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, Department of Water Engineering and Science, College of Civil Engineering, Hunan University, Changsha, Hunan, 410082, China
| | - Jue Wang
- Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, Department of Water Engineering and Science, College of Civil Engineering, Hunan University, Changsha, Hunan, 410082, China
| | - Shiqing Zhou
- Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, Department of Water Engineering and Science, College of Civil Engineering, Hunan University, Changsha, Hunan, 410082, China
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16
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Diao K, Jung D, Farmani R, Fu G, Butler D, Lansey K. Modular interdependency analysis for water distribution systems. Water Res 2021; 201:117320. [PMID: 34139513 DOI: 10.1016/j.watres.2021.117320] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 05/28/2021] [Accepted: 05/29/2021] [Indexed: 06/12/2023]
Abstract
Complexity in water distribution systems (WDSs) poses a challenge for analysis and management of the systems. To reduce the complexity, the recent development of complex network science provides a system decomposition technique that converts a complex WDS with a large number of components into a simple system with a set of interconnected modules. Each module is a subsystem with stronger internal connections than external connections. Thus far, the topological features of the modular structure in WDS have been extensively studied but not the behavioural features, e.g. the hydraulic interdependencies among modules. Therefore, this paper aims to quantitatively measure and graphically visualize the module interdependency in WDSs, which helps understanding the behavioural complexity of WDSs and thus various WDS analyses, such as pipe maintenance, model calibration, rehabilitation, and District Metered Areas planning. Specifically, this study first identifies the WDS's modular structure then measures how changes in the state of one module (i.e. any single pipe failure or perturbed demand within each module) affect the state of another module. Modular interdependencies are summarized in an interdependency matrix and visualized by the digraph. Four real-world systems are analysed, and three of them shows low interdependencies among most of the modules and there are only a few critical modules whose status changes will substantially affect a number of other modules. Hence, highly interconnected topologies may not result in strong and complex module interdependency, which is a fact that simplifies several WDS analysis for practical applications as discussed in this paper.
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Affiliation(s)
- Kegong Diao
- Senior Lecturer in engineering and sustainable development, Faculty of Computing, Engineering and Media, De Montfort University, Gateway House, Leicester LE1 9BH, UK.
| | - Donghwi Jung
- School of Civil, Environmental and Architectural Engineering, Korea University, Seoul 02841, South Korea.
| | - Raziyeh Farmani
- Centre for Water Systems, University of Exeter, North Park Rd, Exeter EX4 4QF, UK.
| | - Guangtao Fu
- Centre for Water Systems, University of Exeter, North Park Rd, Exeter EX4 4QF, UK.
| | - David Butler
- Centre for Water Systems, University of Exeter, North Park Rd, Exeter EX4 4QF, UK.
| | - Kevin Lansey
- Department of Civil and Architectural Engineering and Mechanics, The University of Arizona, Tucson, AZ 85721, USA.
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17
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Bazargan-Lari MR, Taghipour S, Habibi M. Real-time contamination zoning in water distribution networks for contamination emergencies: a case study. Environ Monit Assess 2021; 193:336. [PMID: 33973066 DOI: 10.1007/s10661-021-09068-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 04/11/2021] [Indexed: 06/12/2023]
Abstract
Contamination of urban water distribution systems (WDS) is a critical issue due to the number of victims that might be impacted in a short period of time. Any effective rapid emergency response plan for reducing the number of sick people or deaths among those drinking the polluted water requires a reliable forecast of the water contamination zoning map (CZM). The water CZM is a visual representation of the spread of contamination at the time of contamination detection. This study presents a novel methodology based on the rough set theory (RST) for real-time forecasting of the CZM caused by simultaneous multi-point contamination injection in WDS. Our proposed methodology consists of (i) a Monte Carlo simulation model to capture the uncertainties in a multi-point deliberate contamination, (ii) a numerical simulation model for simulating pipe flow, and (iii) a rough set-based technique for real-time CZM for a WDS equipped with a set of monitoring stations. The proposed methodology can be used for any type of random contamination of WDSs as well as emergencies in deliberate contamination of water distribution networks.
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Affiliation(s)
| | - Sharareh Taghipour
- Department of Mechanical and Industrial Engineering, Ryerson University, Toronto, Canada.
| | - Mehdi Habibi
- Department of Civil Engineering, East Tehran Branch, Islamic Azad University, Tehran, Iran
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18
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Kitajima M, Cruz MC, Williams RBH, Wuertz S, Whittle AJ. Microbial abundance and community composition in biofilms on in-pipe sensors in a drinking water distribution system. Sci Total Environ 2021; 766:142314. [PMID: 33077212 DOI: 10.1016/j.scitotenv.2020.142314] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 09/06/2020] [Accepted: 09/07/2020] [Indexed: 06/11/2023]
Abstract
Collecting biofilm samples from drinking water distribution systems (DWDSs) is challenging due to limited access to the pipes during regular operations. We report here the analysis of microbial communities in biofilm and water samples collected from sensors installed in a DWDS where monochloramine is used as a residual disinfectant. A total of 52 biofilm samples and 14 bulk water samples were collected from 17 pipe sections representing different water ages. Prokaryotic genome copies (bacterial and archaeal 16S rRNA genes, Mycobacterium spp., ammonia-oxidizing bacteria (AOB), and cyanobacteria) were quantified with droplet digital PCR, which revealed the abundance of these genes in both biofilm and water samples. Prokaryotic 16S rRNA gene sequencing analysis was carried out for a subset of the samples (12 samples from four sites). Mycobacterium and AOB species were dominant in the DWDS sections with low water age and sufficient residual monochloramine, whereas Nitrospira species (nitrite-oxidizing bacteria) dominated in the sections with higher water age and depleted monochloramine level, suggesting the occurrence of nitrification in the studied DWDS. The present study provides novel information on the abundance and identity of prokaryotes in biofilms and water in a full-scale operational DWDS.
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Affiliation(s)
- Masaaki Kitajima
- Center for Environmental Sensing and Modeling, Singapore-MIT Alliance for Research and Technology, Singapore 138602, Singapore; Division of Environmental Engineering, Faculty of Engineering, Hokkaido University, Sapporo, Hokkaido 060-8628, Japan.
| | - Mercedes C Cruz
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore 637551, Singapore.
| | - Rohan B H Williams
- Singapore Centre for Environmental Life Sciences Engineering, National University of Singapore, Singapore 117456, Singapore
| | - Stefan Wuertz
- Singapore Centre for Environmental Life Sciences Engineering, National University of Singapore, Singapore 117456, Singapore; School of Civil and Environmental Engineering, Nanyang Technological University, Singapore 639798, Singapore
| | - Andrew J Whittle
- Center for Environmental Sensing and Modeling, Singapore-MIT Alliance for Research and Technology, Singapore 138602, Singapore; Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, United States
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19
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Hemdan BA, El-Taweel GE, Goswami P, Pant D, Sevda S. The role of biofilm in the development and dissemination of ubiquitous pathogens in drinking water distribution systems: an overview of surveillance, outbreaks, and prevention. World J Microbiol Biotechnol 2021; 37:36. [PMID: 33507414 DOI: 10.1007/s11274-021-03008-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2020] [Accepted: 01/19/2021] [Indexed: 12/30/2022]
Abstract
A variety of pathogenic microorganisms can survive in the drinking water distribution systems (DWDS) by forming stable biofilms and, thus, continually disseminating their population through the system's dynamic water bodies. The ingestion of the pathogen-contaminated water could trigger a broad spectrum of illnesses and well-being-related obstacles. These waterborne diseases are a significant concern for babies, pregnant women, and significantly low-immune individuals. This review highlights the recent advances in understanding the microbiological aspects of drinking water quality, biofilm formation and its dynamics, health issues caused by the emerging microbes in biofilm, and approaches for biofilm investigation its prevention and suppression in DWDS.
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20
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Zhang Q, Zheng F, Jia Y, Savic D, Kapelan Z. Real-time foul sewer hydraulic modelling driven by water consumption data from water distribution systems. Water Res 2021; 188:116544. [PMID: 33126001 DOI: 10.1016/j.watres.2020.116544] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 10/18/2020] [Accepted: 10/20/2020] [Indexed: 05/17/2023]
Abstract
Real-time hydraulic modelling can be used to address a wide range of issues in a foul sewer system and hence can help improve its daily operation and maintenance. However, the current bottleneck within real-time FSS modelling is the lack of spatio-temporal inflow data. To address the problem, this paper proposes a new method to develop real-time FSS models driven by water consumption data from associated water distribution systems (WDSs) as they often have a proportionally larger number of sensors. Within the proposed method, the relationship between FSS manholes and WDS water consumption nodes are determined based on their underlying physical connections. An optimization approach is subsequently proposed to identify the transfer factor k between nodal water consumption and FSS manhole inflows based on historical observations. These identified k values combined with the acquired real-time nodal water consumption data drive the FSS real-time modelling. The proposed method is applied to two real FSSs. The results obtained show that it can produce simulated sewer flows and manhole water depths matching well with observations at the monitoring locations. The proposed method achieved high R2, NSE and KGE (Kling-Gupta efficiency) values of 0.99, 0.88 and 0.92 respectively. It is anticipated that real-time models developed by the proposed method can be used for improved FSS management and operation.
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Affiliation(s)
- Qingzhou Zhang
- College of Civil Engineering and Architecture, Zhejiang University, Zhejiang, China.
| | - Feifei Zheng
- College of Civil Engineering and Architecture, Zhejiang University, Zhejiang, China.
| | - Yueyi Jia
- College of Civil Engineering and Architecture, Zhejiang University, Zhejiang, China.
| | - Dragan Savic
- KWR Water Research Institute, Centre for Water Systems, University of Exeter, North Park Road, Exeter EX4 4QF, United Kingdom.
| | - Zoran Kapelan
- Department of Water Management, Delft University of Technology, Delft, the Netherlands.
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21
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Adesoji AT, Call DR. Molecular analysis of florfenicol-resistant bacteria isolated from drinking water distribution systems in Southwestern Nigeria. J Glob Antimicrob Resist 2020; 23:340-4. [PMID: 33166759 DOI: 10.1016/j.jgar.2020.10.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 10/05/2020] [Accepted: 10/08/2020] [Indexed: 11/20/2022] Open
Abstract
OBJECTIVES Use of chloramphenicol or its veterinary analogue florfenicol can selectively favour antibiotic-resistant bacteria. Understanding how resistance is mobilised and disseminated among pathogens is vital in knowing how different bacterial taxa might serve as reservoirs of these genes for pathogenic bacteria. METHODS Bacterial isolates (n=30) were selected on the basis of multidrug resistance and resistance to florfenicol from among 296 bacteria originally isolated from drinking water distribution systems in Southwestern Nigeria. Bacterial identification, minimum inhibitory concentration (MIC) determination for florfenicol, PCR detection of florfenicol resistance genes (floR, fexA and cfx) and sequence analysis were employed to characterise the isolates. RESULTS According to sequence data (16S rDNA, v2-v3 region), 30strains were selected, includingPseudomonas spp. (43.3%), Serratia spp. (13.3%), Proteus spp. (26.7%), Acinetobacter spp. (13.3%) and Providencia rettgeri (3.3%). MICs ranged between >16μg/mL and >1024μg/mL. floR was the only resistance gene detected (11/30; 36.7%). The majority of floR-positive isolates (8/11; 72.7%) were Proteus spp. All floR sequences shared 100% identity and 1-2 synonymous substitutions relative to other published sequences. CONCLUSIONS floR-positive strains in this study were originally selected randomly without antibiotics. Finding floR in four genera without selective enrichment is consistent with widespread distribution of this resistance trait in drinking water systems in Nigeria. Further work is needed to determine whether human and veterinary antibiotic use practices in Nigeria are contributing to proliferation of this important antibiotic resistance trait and to determine whether the presence of floR-producing strains is compromising human and animal health.
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22
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Di D, Wu Z, Wang H, Huang S. Optimal water distribution system based on water rights transaction with administrative management, marketization, and quantification of sediment transport value: A case study of the Yellow River Basin, China. Sci Total Environ 2020; 722:137801. [PMID: 32213437 DOI: 10.1016/j.scitotenv.2020.137801] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Revised: 03/06/2020] [Accepted: 03/06/2020] [Indexed: 06/10/2023]
Abstract
Water rights transaction has proved to be an effective method for constructing an efficient water distribution system (WDS) in various regions of the Yellow River Basin (YRB). In this study, an optimal WDS in the YRB is proposed by considering the comprehensive value of water resources, administrative management system, and market-based system. To accurately quantify the comprehensive value of water resources, the work analysis method of suspended load and bedload based on the emergy theory and time-averaged motion equation is introduced, and the quantification process of sediment transport value in the river course is formulated in the YRB. Based on this, an administrative and market-based game for water rights transaction is formulated. In this double-layer game model, the administrative authorities of the basin (Yellow River Conservancy Commission) and the corresponding regions (Water Resources Department) seek to maximize their own target revenue function/comprehensive value of the water resources. Then, the optimal trading quantity of water in each region and the bargain price can be solved. A case study is presented in the YRB to verify the effectiveness of this method. The results reveal that (1) the error rate of the riverbed shear stress as well as the sediment transport rate between the theoretical value and the calculated value does not exceed 8.76%, which indicates the rationality of the calculation method of sediment transport value; (2) the proposed dynamic differential game and pricing game perform well in determining the optimal trading quantity of water in each region. They also reveal the bargain price with optimal results of ¥ 4151.1456 half yearly and ¥ 8197.3466 per year in 2018, outperforming other methodologies.
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Affiliation(s)
- Danyang Di
- School of Water Conservancy Engineering, Zhengzhou University, Zhengzhou, Henan 450001, PR China
| | - Zening Wu
- School of Water Conservancy Engineering, Zhengzhou University, Zhengzhou, Henan 450001, PR China
| | - Huiliang Wang
- School of Water Conservancy Engineering, Zhengzhou University, Zhengzhou, Henan 450001, PR China.
| | - Shuoqiao Huang
- School of Water Conservancy Engineering, Zhengzhou University, Zhengzhou, Henan 450001, PR China
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23
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Mohammadi A, Faraji M, Ebrahimi AA, Nemati S, Abdolahnejad A, Miri M. Comparing THMs level in old and new water distribution systems; seasonal variation and probabilistic risk assessment. Ecotoxicol Environ Saf 2020; 192:110286. [PMID: 32036101 DOI: 10.1016/j.ecoenv.2020.110286] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 01/04/2020] [Accepted: 01/31/2020] [Indexed: 06/10/2023]
Abstract
Trihalomethanes (THMs) in drinking water are associated with many chemical parameters in water. However, the available evidence on the relationship between physical parameters of the water distribution system (WDS) and THMs is still scarce; therefore, this study aimed to compare the THMs concentration in the old and new WDS in Yazd, Iran. Moreover, we investigated the seasonal trend and health risk assessment of exposure to THMs through ingestion, dermal, and inhalation pathways. Mann-Whitney test was applied to compare THMs between old and new WDS as well as fall season and winter season. The order of THM concentrations was: chloroform > BDCM > DBCM > bromoform. The maximum levels of THMs in the fall and winter were 31 and 39 ppb, respectively, which were less than the WHO recommended limits for drinking water, i.e., <200 ppb. There was a significant difference between the concentration of BDCM in autumn and winter (P-value = 0.01). There was a marginally significant difference between THM concentration in the autumn and winter (P-value 0.09). The total concentration of THMs and chloroform in the old WDS were significantly higher than the new WDS. The mean values of lifetime cancer risks (LTCR) for oral, dermal, and inhalation exposure pathways to THMs were in the acceptable and low-risk levels. The inhalation exposure pathway had the highest LTCR from among the three mentioned exposure pathways. The hazard index was found to be < 1 through oral and dermal pathways. Moreover, the sensitivity analysis revealed that the ingestion rate for oral exposure, the exposure time for dermal and exposure duration for the inhalation exposure pathway had the highest impact on chronic daily intake (CDI). Our finding confirmed that THM concentration in tap water was associated with the lifespan of WDS and this finding could be useful for urban planners and decision-makers.
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Affiliation(s)
- Amir Mohammadi
- Department of Public Health, Maragheh University of Medical Sciences, Maragheh, Iran; Student Research Committee, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
| | - Maryam Faraji
- Environmental Health Engineering Research Center, Kerman University of Medical Sciences, Kerman, Iran; Department of Environmental Health, School of Public Health, Kerman University of Medical Sciences, Kerman, Iran
| | - Ali Asghar Ebrahimi
- Environmental Health Science and Technology Research Center, Department of Environmental Health Engineering, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
| | - Sepideh Nemati
- Health Faculty, Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Ali Abdolahnejad
- Student Research Committee, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
| | - Mohammad Miri
- Non-communicable Disease Research Center, Department of Environmental Health Engineering, School of Public Health, Sabzevar University of Medical Sciences, Sabzevar, Iran.
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Zhang Q, Zheng F, Kapelan Z, Savic D, He G, Ma Y. Assessing the global resilience of water quality sensor placement strategies within water distribution systems. Water Res 2020; 172:115527. [PMID: 32004913 DOI: 10.1016/j.watres.2020.115527] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 01/16/2020] [Accepted: 01/19/2020] [Indexed: 06/10/2023]
Abstract
Water quality sensors are often spatially distributed in water distribution systems (WDSs) to detect contamination events and monitor quality parameters (e.g., chlorine residual levels), thereby ensuring safety of a WDS. The performance of a water quality sensor placement strategy (WQSPS) is not only affected by sensor spatial deployment that has been extensively analyzed in literature, but also by possible sensor failures that have been rarely explored so far. However, enumerating all possible sensor failure scenarios is computationally infeasible for a WQSPS with a large number of sensors. To this end, this paper proposes an evolutionary algorithm (EA) based method to systematically and efficiently investigate the WQSPS' global resilience considering all likely sensor failures. First, new metrics are developed in the proposed method to assess the global resilience of a WQSPS. This is followed by a proposal of an efficient optimization approach based on an EA to identify the values of global resilience metrics. Finally, the sensors within the WQSPS are ranked to identify their relative importance in maintaining the WQSPS's detection performance. Two real-world WDSs with four WQSPSs for each case study are used to demonstrate the utility of the proposed method. Results show that: (i) compared to the traditional global resilience analysis method, the proposed EA-based approach identifies improved values of global resilience metrics, (ii) the WQSPSs that deploy sensors close to large demand users are overall more resilient in handling sensor failures relative to other design solutions, thus offering important insight to facilitate the selection of WQSPSs, and (iii) sensor rankings based on the global resilience can identify those sensors whose failure would significantly reduce the WQSPS's performance thereby providing guidance to enable effective water quality sensor management and maintenance.
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Affiliation(s)
- Qingzhou Zhang
- College of Civil Engineering and Architecture, Zhejiang University, A501, Anzhong Building, Zijingang Campus, 866 Yuhangtang Rd, Hangzhou, 310058, China.
| | - Feifei Zheng
- College of Civil Engineering and Architecture, Zhejiang University, A501, Anzhong Building, Zijingang Campus, 866 Yuhangtang Rd, Hangzhou, 310058, China.
| | - Zoran Kapelan
- Delft University of Technology, Faculty of Civil Engineering and Geosciences, Department of Water Management, Stevinweg 1, 2628 CN, Delft, Netherlands.
| | - Dragan Savic
- KWR Water Research Institute, Centre for Water Systems, University of Exeter, North Park Road, Exeter, EX4 4QF, United Kingdom.
| | - Guilin He
- School of Municipal and Environmental Engineering, Shandong Jianzhu University, China.
| | - Yiyi Ma
- College of Civil Engineering and Architecture, Zhejiang University, A501, Anzhong Building, Zijingang Campus, 866 Yuhangtang Rd, Hangzhou, 310058, China.
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Dong F, Chen J, Li C, Ma X, Jiang J, Lin Q, Lin C, Diao H. Evidence-based analysis on the toxicity of disinfection byproducts in vivo and in vitro for disinfection selection. Water Res 2019; 165:114976. [PMID: 31445306 DOI: 10.1016/j.watres.2019.114976] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Revised: 08/08/2019] [Accepted: 08/11/2019] [Indexed: 06/10/2023]
Abstract
Disinfection is a key step in drinking water treatment process to prevent water-borne infections. However, reactions between chlorine, one of the most common disinfectants, and natural organic matter (NOM) often lead to the formation of hazardous disinfection byproducts (DBPs). However, the cytotoxicity of some DBPs is still poorly understood. Such knowledge is critical for proper selection of disinfection processes. We investigated the effects of DBPs on mouse acute liver injury. The exacerbation of liver damage increased with the DBPs concentrations, likely due to the increased hepatic macrophages. Haloacetonitriles (HANs) and haloketones (HKs) are more toxic to Human Hepatocellular (Hep3B) cells than trihalomethanes (THMs). Cytotoxicity of DBPs were governed by the halogen type (brominated DBPs > chlorinated DBPs) and the numbers of halogen atoms per molecule. Then, we used the pilot-scale WDS to study the best conditions for reducing the formation of DBPs. The result showed that the formation of DBPs followed the order: stainless-steel (SS) > ductile iron (DI) > polyethylene (PE) pipe. Higher flowrate promoted the formation of DBPs in all three pipes. The results suggest that the formation of DBPs in chlorine disinfection can be reduced by using PE pipes and low flow rate in water distribution systems (WDS).
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Affiliation(s)
- Feilong Dong
- College of Civil Engineering and Architecture, Zhejiang University, Hangzhou, 310027, China
| | - Jianing Chen
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Cong Li
- School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai, 200433, China.
| | - Xingmao Ma
- Zachery Department of Civil Engineering, Texas A&M University, TAMU 3136, College Station, TX, 77843, USA
| | - Jingjing Jiang
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Qiufeng Lin
- College of Civil Engineering and Architecture, Zhejiang University, Hangzhou, 310027, China
| | - Chenhong Lin
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Hongyan Diao
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China.
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26
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Zhang T, He G, Dong F, Zhang Q, Huang Y. Chlorination of enoxacin (ENO) in the drinking water distribution system: Degradation, byproducts, and toxicity. Sci Total Environ 2019; 676:31-39. [PMID: 31029898 DOI: 10.1016/j.scitotenv.2019.04.275] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Revised: 04/17/2019] [Accepted: 04/18/2019] [Indexed: 06/09/2023]
Abstract
Chlorine is widely used as a drinking water disinfectant to ensure water security. However, the transformation mechanisms of its degradation of emerging pollutants within the water distribution system (WDS) is insufficiently understood. Thus, the kinetics, degradation byproducts, and toxicity of the chlorination of enoxacin (ENO, a type of emerging pollutant) were explored in a pilot-scale WDS for the first time. It was found that the chlorination rate of ENO was higher in deionized water (DW) than in the pilot-scale WDS, and the degradation followed second-order kinetics in DW. The degradation efficiency was found to be sensitive to pH, and was highest at a pH of 7.4. The chlorination rate of ENO increased with increasing temperature in both DW and WDS. For different pipe materials, the relative performance of ENO chlorination efficiency followed the order of steel pipe > ductile iron pipe > polyethylene (PE) pipe. Seven intermediates were identified during ENO chlorination, and the primary oxidation reaction involved the cleavage of the piperazine group. Finally, it was found that the potential for chlorine toxicity in treated drinking water in the presence of ENO is higher than it is without this pollutant.
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Affiliation(s)
- Tuqiao Zhang
- College of Civil Engineering and Architecture, Zhejiang University, 866 Yuhangtang Rd, Hangzhou 310058, China
| | - Guilin He
- College of Civil Engineering and Architecture, Zhejiang University, 866 Yuhangtang Rd, Hangzhou 310058, China.
| | - Feilong Dong
- College of Civil Engineering and Architecture, Zhejiang University, 866 Yuhangtang Rd, Hangzhou 310058, China
| | - Qingzhou Zhang
- College of Civil Engineering and Architecture, Zhejiang University, 866 Yuhangtang Rd, Hangzhou 310058, China
| | - Yuan Huang
- College of Civil Engineering and Architecture, Zhejiang University, 866 Yuhangtang Rd, Hangzhou 310058, China
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27
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Yan H, Wang Q, Wang J, Xin K, Tao T, Li S. A simple but robust convergence trajectory controlled method for pressure driven analysis in water distribution system. Sci Total Environ 2019; 659:983-994. [PMID: 31096428 DOI: 10.1016/j.scitotenv.2018.12.374] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Revised: 12/11/2018] [Accepted: 12/24/2018] [Indexed: 06/09/2023]
Abstract
This paper presents a novel convergence trajectory controlled method to perform pressure driven analysis (PDA) in water distribution systems (WDSs). The proposed method makes forcibly the convergence error decrease continuously, which is fundamentally different from the traditional uncontrolled convergence process, thereby ensuring a robust convergence behavior for hydraulic analysis with PDA in WDS. In addition, two Relaxation Factor section strategies are developed to control the convergence trajectory towards the desired downtrends. The novel methodology is implemented based on EPANET3.0 by modifying the source code which is available in GitHub (https://github.com/OpenWaterAnalytics/epanet-dev). Firstly, the improved code was validated extensively with a benchmark WDS under rigorous boundary conditions. Subsequently, four challenging different size WDSs are also tested in terms of the effectiveness and efficiency. The results illustrate that the proposed method is able to enable the convergence of PDA to be more stable and more robust, even under some extreme abnormal boundary conditions.
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Affiliation(s)
- Hexiang Yan
- College of Environmental Science and Engineering, Tongji University, Shanghai, China
| | - Qiongyu Wang
- College of Environmental Science and Engineering, Tongji University, Shanghai, China
| | - Jiaying Wang
- College of Environmental Science and Engineering, Tongji University, Shanghai, China
| | - Kunlun Xin
- College of Environmental Science and Engineering, Tongji University, Shanghai, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, China.
| | - Tao Tao
- College of Environmental Science and Engineering, Tongji University, Shanghai, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, China
| | - Shuping Li
- College of Environmental Science and Engineering, Tongji University, Shanghai, China
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28
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Dong F, Li C, Crittenden J, Zhang T, Lin Q, He G, Zhang W, Luo J. Sulfadiazine destruction by chlorination in a pilot-scale water distribution system: Kinetics, pathway, and bacterial community structure. J Hazard Mater 2019; 366:88-97. [PMID: 30502576 DOI: 10.1016/j.jhazmat.2018.11.096] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2018] [Revised: 11/22/2018] [Accepted: 11/23/2018] [Indexed: 06/09/2023]
Abstract
Sulfadiazine (SDZ) has been frequently detected in surface waters in recent years. We evaluated the kinetics, mechanisms, intermediate products and bacterial community structure that result from the reaction of SDZ with free chlorine (HOCl/OCl-). We examined this in a pilot-scale water distribution system. Neutral pH had the fastest rate of destruction of SDZ. A second-order reaction constant for the destruction of SDZ by chlorine increased with increasing concentration of free chlorine (FC). For different pipe materials, the rate of SDZ degradation decreased as follows: stainless steel (SS) pipe > polyethylene (PE) pipe > ductile iron (DI) pipe. Based on the less complex bacterial diversity and more chlorine-resistant by 16S ribosomal ribonucleic acid (rRNA) gene analysis, SS pipe and PE pipe were more suitable in SDZ degradation in water distribution system (WDS) than DI pipe. In addition, the transformation products from SDZ chlorination were identified by gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry, and the products included SO2 extrusion products, haloacetic acids and trihalomethanes. Toxicity tests further confirmed that the toxicity of SDZ chlorination was higher both in low FC (0.7 mg/L) and high FC (1.3 mg/L) in WDS.
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Affiliation(s)
- Feilong Dong
- College of Civil Engineering and Architecture, Zhejiang University, Hangzhou, 310027, China
| | - Cong Li
- College of Civil Engineering and Architecture, Zhejiang University, Hangzhou, 310027, China; School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai, 200433, China.
| | - John Crittenden
- School of Civil and Environmental Engineering, Georgia Institute of Technology, USA
| | - Tuqiao Zhang
- College of Civil Engineering and Architecture, Zhejiang University, Hangzhou, 310027, China
| | - Qiufeng Lin
- College of Civil Engineering and Architecture, Zhejiang University, Hangzhou, 310027, China
| | - Guilin He
- College of Civil Engineering and Architecture, Zhejiang University, Hangzhou, 310027, China
| | - Weiqiu Zhang
- School of Civil and Environmental Engineering, Georgia Institute of Technology, USA
| | - Jinming Luo
- School of Civil and Environmental Engineering, Georgia Institute of Technology, USA
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29
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Qiu W, Li W, He J, Zhao H, Liu X, Yuan Y. Variations regularity of microorganisms and corrosion of cast iron in water distribution system. J Environ Sci (China) 2018; 74:177-185. [PMID: 30340671 DOI: 10.1016/j.jes.2018.03.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Revised: 03/03/2018] [Accepted: 03/05/2018] [Indexed: 06/08/2023]
Abstract
Corrosion, one of the most common problems of metal pipe for water supply, generally leads to poor water quality, bacteria proliferation, water capacity decrease and other problems. As microorganisms affect corrosion by changing the characteristics of metal surface, the mechanism of microbial corrosion still remains unclear. The corrosion behavior of ductile cast iron is implemented in the dynamic flow and static conditions, in which variations of water quality and microbial community are analyzed in details. The results show that if the corrosion rate of ductile cast iron decreases, the corrosion of cast iron will result in a lower DO and a higher total iron in bulk water. The number of microorganisms is not a decisive factor of corrosion, even though the counts of bacteria had a close relationship with DO. On the basis of the detection of the 10 kinds of nitrate-reducing bacteria by Miseq sequencing, NRB of the biofilm biomass accounts for 18.3% on the 30th day and 20.5% on the 55th day. Even though aerobic NRBs go into the biofilm later than the facultative anaerobic NRBs, the growth of the anaerobic NRBs is not affected.
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Affiliation(s)
- Wei Qiu
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China.
| | - Weiyu Li
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China; Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150069, China
| | - Junguo He
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China.
| | - Hongyu Zhao
- School of Architecture and Planning, Jilin Jianzhu University, Jilin 130118, China
| | - Xiuming Liu
- School of Foreign Languages, Harbin University of Science and Technology, Harbin 150080, China
| | - Yixing Yuan
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
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30
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Dawidowicz J. Evaluation of a pressure head and pressure zones in water distribution systems by artificial neural networks. Neural Comput Appl 2018; 30:2531-8. [PMID: 30363755 DOI: 10.1007/s00521-017-2844-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2015] [Accepted: 01/05/2017] [Indexed: 10/26/2022]
Abstract
Water distribution system design is inherently associated with hydraulic calculations that require thorough evaluation of obtained results and accuracy of the applied solution. Currently, there are no programs that will replace a designer in these tasks, and there likely will not be such programs. However, some individuals are trying to develop computer programs featuring a certain degree of creativity to facilitate user decision making. In water distribution system design and hydraulic calculations, one should, inter alia, check pressure heads in different parts of the system. It is also important to establish whether the system should contain one or more pressure zones. This determination is connected with the appropriate location of booster and pressure reducing stations. In this paper, the nominal variable is defined. The classes of this variable describe problems related to a value of pressure and division of the water distribution system into pressure zones. By choosing one of the classes, an artificial neural network determines the problems that may arise in a given part of the water distribution system. The classification is conducted based on neural network input variables describing the specific parameters that affect water distribution system design, such as land relief, loss of pressure, pipe roughness and distance to a water supply. The paper presents a new approach that extends traditional methods of hydraulic calculations for water distribution systems by introducing the evaluation of a pressure head and the analysis of design concepts of pressure zones by using artificial neural networks.
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31
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Khorshidi MS, Nikoo MR, Sadegh M. Optimal and objective placement of sensors in water distribution systems using information theory. Water Res 2018; 143:218-228. [PMID: 29960176 DOI: 10.1016/j.watres.2018.06.050] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Revised: 05/11/2018] [Accepted: 06/20/2018] [Indexed: 06/08/2023]
Abstract
Optimization-based deployment of contamination warning system in water distribution systems has been widely used in the literature, due to their superior performance compared to rule- and opinion-based approaches. However, optimization techniques impose an excessive computational burden, which in turn is compensated for by shrinking the problem's decision space and/or using faster optimization algorithms with less accuracy. This imposes subjectivity in interpretation of the system and associated risks, and undermines model's accuracy by not exploring the entire feasible space. We propose a framework that uses information theoretic techniques, including value of information and transinformation entropy, for optimal sensor placement. This can be used either as pre-selection, i.e. pinpointing best potential locations of sensors to be in turn used in optimization framework, or ultimate selection, i.e. single-handedly selecting sensor locations from the feasible space. The proposed framework is then applied to Lamerd water distribution system, in Fars province, Iran, and the results are compared to the suggested potential locations of sensors in previous studies and results of TEVA-SPOT model. The proposed information theoretic scheme enhances the decision space, provides more accurate results, significantly reduces the computational burden, and warrants objective selection of sensor placement.
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Affiliation(s)
- Mohammad S Khorshidi
- School of Engineering, Department of Environmental Engineering, Shiraz University, Shiraz, Iran.
| | - Mohammad Reza Nikoo
- School of Engineering, Department of Environmental Engineering, Shiraz University, Shiraz, Iran.
| | - Mojtaba Sadegh
- Department of Civil Engineering, Boise State University, Boise, USA.
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32
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Li C, Wang D, Xu X, Xu M, Wang Z. Spatial variations in the occurrence of potentially genotoxic disinfection by-products in drinking water distribution systems in China. Environ Pollut 2017; 231:1463-1468. [PMID: 28911795 DOI: 10.1016/j.envpol.2017.09.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Revised: 08/15/2017] [Accepted: 09/04/2017] [Indexed: 06/07/2023]
Abstract
We investigated the occurrence of disinfection by-products (DBPs) with genotoxic potential in plant effluent and distribution water samples from four drinking water treatment plants in two Chinese cities using comprehensive two-dimensional gas chromatography-quadrupole mass spectrometry. We tested the samples for 37 DBPs with genotoxic potential, which we had previously identified and prioritized in water under controlled laboratory conditions. Thirty of these DBPs were found in the water samples at detection frequencies of between 10% and 100%, and at concentrations between 3.90 and 1.77 × 103 ng/L. Of the DBPs detected, the concentrations of 1,1,1-trichloropropan-2-one were highest, and ranged from 299 to 1.77 × 103 ng/L with an average of 796 ng/L. The concentrations of 6-chloro-2-N-propan-2-yl-1,3,5-triazine-2,4-diamine and 2,6-ditert-butylcyclohexa-2,5-diene-1,4-dione were also much higher, and ranged from 107 to 721 ng/L, and from 152 to 504 ng/L, respectively. Concentrations of 1,1,1-trichloropropan-2-one, 2-chloro-1-phenylethanone, 2,2-dichloro-1-phenylethanone and 6-chloro-2-N-propan-2-yl-1,3,5-triazine-2,4-diamine were highest at or near the treatment plants and decreased with increasing distance from the plants. Patterns in the concentrations of benzaldehyde, 2-phenylpropan-2-ol, and 1-methylnaphthalene differed between plants. The levels of DBPs such as 4-ethylbenzaldehyde, (E)-non-2-enal, and 1-phenylethanone were relatively constant within the distribution systems, even at the furthest sampling points (20 km < d < 30 km). A risk assessment showed that there was no risk to human health. It is, however, important to note that, because of limited availability of toxicity data, only five DBPs were evaluated in this study. The risks to health associated with exposure to the target potentially genotoxic DBPs should not be ignored because of their prolonged existence in drinking water.
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Affiliation(s)
- Chunmei Li
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China
| | - Donghong Wang
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China.
| | - Xiong Xu
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China
| | - Meijia Xu
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China
| | - Zijian Wang
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Science, Chinese Academy of Sciences, Beijing, China
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33
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Güngör M, Yarar U, Firat M. Reduction of water losses by rehabilitation of water distribution network. Environ Monit Assess 2017; 189:498. [PMID: 28895003 DOI: 10.1007/s10661-017-6219-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Accepted: 09/04/2017] [Indexed: 06/07/2023]
Abstract
Physical or real losses may be indicated as the most important component of the water losses occurring in a water distribution network (WDN). The objective of this study is to examine the effects of piping material management and network rehabilitation on the physical water losses and water losses management in a WDN. For this aim, the Denizli WDN consisting of very old pipes that have exhausted their economic life is selected as the study area. The fact that the current network is old results in the decrease of pressure strength, increase of failure intensity, and inefficient use of water resources thus leading to the application of the rehabilitation program. In Denizli, network renewal works have been carried out since the year 2009 under the rehabilitation program. It was determined that the failure rate at regions where network renewal constructions have been completed decreased down to zero level. Renewal of piping material enables the minimization of leakage losses as well as the failure rate. On the other hand, the system rehabilitation has the potential to amortize itself in a very short amount of time if the initial investment cost of network renewal is considered along with the operating costs of the old and new systems, as well as water loss costs. As a result, it can be stated that renewal of piping material in water distribution systems, enhancement of the physical properties of the system, provide significant contributions such as increase of water and energy efficiency and more effective use of resources.
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Affiliation(s)
- Mahmud Güngör
- Denizli Water and Sewerage Authority, Denizli, Turkey
| | - Ufuk Yarar
- Denizli Water and Sewerage Authority, Denizli, Turkey
| | - Mahmut Firat
- Inonu University Civil Engineering Department, Malatya, Turkey.
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34
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Klise KA, Bynum M, Moriarty D, Murray R. A SOFTWARE FRAMEWORK FOR ASSESSING THE RESILIENCE OF DRINKING WATER SYSTEMS TO DISASTERS WITH AN EXAMPLE EARTHQUAKE CASE STUDY. Environ Model Softw 2017; 95:420-431. [PMID: 30505210 PMCID: PMC6262876 DOI: 10.1016/j.envsoft.2017.06.022] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Water utilities are vulnerable to a wide variety of human-caused and natural disasters. The Water Network Tool for Resilience (WNTR) is a new open source Python™ package designed to help water utilities investigate resilience of water distribution systems to hazards and evaluate resilience-enhancing actions. In this paper, the WNTR modeling framework is presented and a case study is described that uses WNTR to simulate the effects of an earthquake on a water distribution system. The case study illustrates that the severity of damage is not only a function of system integrity and earthquake magnitude, but also of the available resources and repair strategies used to return the system to normal operating conditions. While earthquakes are particularly concerning since buried water distribution pipelines are highly susceptible to damage, the software framework can be applied to other types of hazards, including power outages and contamination incidents.
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Affiliation(s)
- Katherine A Klise
- Geotechnology and Engineering, Sandia National Laboratories, PO Box 5800, Mail Stop 0750, Albuquerque, NM 87185-1137, USA
| | - Michael Bynum
- School of Chemical Engineering, Purdue University, 480 Stadium Mall Drive, West Lafayette, IN 47907, USA
| | - Dylan Moriarty
- Geotechnology and Engineering, Sandia National Laboratories, PO Box 5800, Mail Stop 0750, Albuquerque, NM 87185-1137, USA
| | - Regan Murray
- National Homeland Security Research Center, United States Environmental Protection Agency, 26 W. Martin Luther King Dr., Cincinnati, OH 45268, USA
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35
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Diao K, Sweetapple C, Farmani R, Fu G, Ward S, Butler D. Global resilience analysis of water distribution systems. Water Res 2016; 106:383-393. [PMID: 27750127 DOI: 10.1016/j.watres.2016.10.011] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Revised: 09/13/2016] [Accepted: 10/03/2016] [Indexed: 06/06/2023]
Abstract
Evaluating and enhancing resilience in water infrastructure is a crucial step towards more sustainable urban water management. As a prerequisite to enhancing resilience, a detailed understanding is required of the inherent resilience of the underlying system. Differing from traditional risk analysis, here we propose a global resilience analysis (GRA) approach that shifts the objective from analysing multiple and unknown threats to analysing the more identifiable and measurable system responses to extreme conditions, i.e. potential failure modes. GRA aims to evaluate a system's resilience to a possible failure mode regardless of the causal threat(s) (known or unknown, external or internal). The method is applied to test the resilience of four water distribution systems (WDSs) with various features to three typical failure modes (pipe failure, excess demand, and substance intrusion). The study reveals GRA provides an overview of a water system's resilience to various failure modes. For each failure mode, it identifies the range of corresponding failure impacts and reveals extreme scenarios (e.g. the complete loss of water supply with only 5% pipe failure, or still meeting 80% of demand despite over 70% of pipes failing). GRA also reveals that increased resilience to one failure mode may decrease resilience to another and increasing system capacity may delay the system's recovery in some situations. It is also shown that selecting an appropriate level of detail for hydraulic models is of great importance in resilience analysis. The method can be used as a comprehensive diagnostic framework to evaluate a range of interventions for improving system resilience in future studies.
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Affiliation(s)
- Kegong Diao
- Centre for Water Systems, University of Exeter, North Park Rd, Exeter, EX4 4QF, UK; Faculty of Technology, De Montfort University, Mill Lane, Leicester, LE2 7DR, UK.
| | - Chris Sweetapple
- Centre for Water Systems, University of Exeter, North Park Rd, Exeter, EX4 4QF, UK.
| | - Raziyeh Farmani
- Centre for Water Systems, University of Exeter, North Park Rd, Exeter, EX4 4QF, UK.
| | - Guangtao Fu
- Centre for Water Systems, University of Exeter, North Park Rd, Exeter, EX4 4QF, UK.
| | - Sarah Ward
- Centre for Water Systems, University of Exeter, North Park Rd, Exeter, EX4 4QF, UK.
| | - David Butler
- Centre for Water Systems, University of Exeter, North Park Rd, Exeter, EX4 4QF, UK.
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36
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Wu Y, Liu S, Wu X, Liu Y, Guan Y. Burst detection in district metering areas using a data driven clustering algorithm. Water Res 2016; 100:28-37. [PMID: 27176651 DOI: 10.1016/j.watres.2016.05.016] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Revised: 05/01/2016] [Accepted: 05/04/2016] [Indexed: 06/05/2023]
Abstract
This paper describes a novel methodology for burst detection in a water distribution system. The proposed method has two stages. In the first stage, a clustering algorithm was employed for outlier detection, while the second stage identified the presence of bursts. An important feature of this method is that data analysis is carried out dependent on multiple flow meters whose measurements vary simultaneously in a district metering area (DMA). Moreover, the clustering-based method can automatically cope with non-stationary conditions in historical data; namely, the method has no prior data selection process. An example application of this method has been implemented to confirm that relatively large bursts (simulated by flushing) with short duration can be detected effectively. Noticeably, the method has a low false positive rate compared with previous studies and appearance of detected abnormal water usage consists with weather changes, showing great promise in real application to multi-inlet and multi-outlet DMAs.
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Affiliation(s)
- Yipeng Wu
- School of Environment, Tsinghua University, 100084, Beijing, China
| | - Shuming Liu
- School of Environment, Tsinghua University, 100084, Beijing, China.
| | - Xue Wu
- School of Environment, Tsinghua University, 100084, Beijing, China
| | - Youfei Liu
- Shaoxing Water Co., Ltd., 312000, Zhejiang, China
| | - Yisheng Guan
- Shaoxing Water Co., Ltd., 312000, Zhejiang, China
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37
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Zhang N, Xu B, Qi F, Kumirska J. The occurrence of haloanisoles as an emerging odorant in municipal tap water of typical cities in China. Water Res 2016; 98:242-249. [PMID: 27107142 DOI: 10.1016/j.watres.2016.04.023] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Revised: 04/10/2016] [Accepted: 04/13/2016] [Indexed: 06/05/2023]
Abstract
In this study, occurrence of the haloanisoles odorous compounds in tap water of Chinese cities, were investigated by solid-phase microextraction (SPME)-GC/MS analysis. This study revealed the occurrence of four kinds of haloanisoles in 22 cities of China in both summer and winter. Except 2,4,6-tribromoanisole (2,4,6-TBA), all studied haloanisoles showed higher frequency of detection. 2,3,6-Trichloroanisole (2,3,6-TCA) and 2,3,4-trichloroanisole (2,3,4-TCA) showed higher occurrence concentration; however, the relative odor values of them was lower. These values of 2,4,6-TBA and 2,4,6-trichloroanisole (2,4,6-TCA) in all samples were greater than zero in both summer and winter, indicating the odor from haloanisoles could be felt by human noise. This study further showed that Beijing exhibited most serious occurrence of haloanisoles that were depended on the season and drinking water distribution system (country and city). From this study, it was confirmed that haloanisoles was important taste and odor compounds in tap water of China. Based on the survey of occurrence of halophenol and residual chlorine, the possible source for the formation of haloanisoles in tap water was discussed. Furthermore, several suggestions on control the haloanisoles odor in drinking water treatment plant and water distribution system were provided.
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Affiliation(s)
- Ni Zhang
- Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, PR China
| | - Bingbing Xu
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, PR China.
| | - Fei Qi
- Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, PR China.
| | - Jolanta Kumirska
- Department of Environmental Analysis, Faculty of Chemistry, University of Gdansk, Wita Stwosza 63, 80-308, Poland
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38
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Li C, Wang Z, Yang YJ, Liu J, Mao X, Zhang Y. Transformation of bisphenol A in water distribution systems: a pilot-scale study. Chemosphere 2015; 125:86-93. [PMID: 25550112 DOI: 10.1016/j.chemosphere.2014.11.047] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2014] [Revised: 11/18/2014] [Accepted: 11/22/2014] [Indexed: 06/04/2023]
Abstract
Halogenations of bisphenol A (BPA) in a pilot-scale water distribution system (WDS) of a cement-lined ductile cast iron pipe were investigated. The water in the pilot-scale WDS was chlorinated with a free chlorine concentration of 0.7 mg L(-1) using sodium hypochlorite, and with an initial BPA concentration of 100 μg L(-1) was spiked in the WDS. Halogenated compounds in the BPA experiments were identified using EI/GC/MS and GC. Several BPA congeners, including 2-chlorobisphenol A (MCBPA), dichlorobisphenol A (D2-CBPA), 2,2',6-trichlorobisphenol A (T3CBPA), 2,2',6,6'-tetrachlorobisphenol A (T4CBPA), 2-bromobisphenol A (MBBPA), and bromochlorobisphenol A (MBMCBPA) were found. Moreover, further halogenation yielded other reaction intermediates, including 2,4,6-trichlorophenol (T3CP), dichlorobisphenol A, bromodichlorophenol, and dibromochlorophenol. After halogenation for 120min, most of the abovementioned reaction intermediates disappeared and were replaced by trihalomethanes (THMs). Based on these experimental findings, the halogenation process of BPA oxidation in a WDS includes three stages: (1) halogenation on the aromatic ring; (2) chlorine or bromine substitution followed by cleavage of the α-C bond on the isopropyl moiety with a positive partial charge and a β'-C bond on the benzene moiety with a negative partial charge; and (3) THMs and a minor HAA formation from phenolic intermediates through the benzene ring opening with a chlorine and bromine substitution of the hydrogen on the carbon atoms. The oxidation mechanisms of the entire transformation from BPA to THM/HAA in the WDS were proposed.
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Affiliation(s)
- Cong Li
- College of Civil Engineering and Architecture, Zhejiang University, Hangzhou, China
| | - Zilong Wang
- College of Civil Engineering and Architecture, Zhejiang University, Hangzhou, China
| | - Y Jeffrey Yang
- U.S. EPA, National Risk Management Research Laboratory, Cincinnati, USA
| | - Jingqing Liu
- College of Civil Engineering and Architecture, Zhejiang University, Hangzhou, China
| | - Xinwei Mao
- College of Civil Engineering and Architecture, Zhejiang University, Hangzhou, China
| | - Yan Zhang
- College of Civil Engineering and Architecture, Zhejiang University, Hangzhou, China.
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39
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Diao K, Rauch W. Controllability analysis as a pre-selection method for sensor placement in water distribution systems. Water Res 2013; 47:6097-6108. [PMID: 23948563 DOI: 10.1016/j.watres.2013.07.026] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2013] [Revised: 07/15/2013] [Accepted: 07/18/2013] [Indexed: 06/02/2023]
Abstract
Detection of contamination events in water distribution systems is a crucial task for maintaining water security. Online monitoring is considered as the most cost-effective technology to protect against the impacts of contaminant intrusions. Optimization methods for sensor placement enable automated sensor layout design based on hydraulic and water quality simulation. However, this approach results in an excessive computational burden. In this paper we outline the application of controllability analysis as preprocessing method for sensor placement. Based on case studies we demonstrate that the method decreases the number of decision variables for subsequent optimization dramatically to app. 30 to 40 percent.
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Affiliation(s)
- Kegong Diao
- Unit of Environmental Engineering, University of Innsbruck, Technikerstrasse 13, Innsbruck 6020, Tirol, Austria.
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40
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Kumpel E, Nelson KL. Comparing microbial water quality in an intermittent and continuous piped water supply. Water Res 2013; 47:5176-88. [PMID: 23866140 DOI: 10.1016/j.watres.2013.05.058] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2013] [Revised: 05/30/2013] [Accepted: 05/31/2013] [Indexed: 05/20/2023]
Abstract
Supplying piped water intermittently is a common practice throughout the world that increases the risk of microbial contamination through multiple mechanisms. Converting an intermittent supply to a continuous supply has the potential to improve the quality of water delivered to consumers. To understand the effects of this upgrade on water quality, we tested samples from reservoirs, consumer taps, and drinking water provided by households (e.g. from storage containers) from an intermittent and continuous supply in Hubli-Dharwad, India, over one year. Water samples were tested for total coliform, Escherichia coli, turbidity, free chlorine, and combined chlorine. While water quality was similar at service reservoirs supplying the continuous and intermittent sections of the network, indicator bacteria were detected more frequently and at higher concentrations in samples from taps supplied intermittently compared to those supplied continuously (p < 0.01). Detection of E. coli was rare in continuous supply, with 0.7% of tap samples positive compared to 31.7% of intermittent water supply tap samples positive for E. coli. In samples from both continuously and intermittently supplied taps, higher concentrations of total coliform were measured after rainfall events. While source water quality declined slightly during the rainy season, only tap water from intermittent supply had significantly more indicator bacteria throughout the rainy season compared to the dry season. Drinking water samples provided by households in both continuous and intermittent supplies had higher concentrations of indicator bacteria than samples collected directly from taps. Most households with continuous supply continued to store water for drinking, resulting in re-contamination, which may reduce the benefits to water quality of converting to continuous supply.
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Affiliation(s)
- Emily Kumpel
- Department of Civil and Environmental Engineering, University of California, Berkeley, CA 94720-1710, USA
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41
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Abstract
In the field of water distribution system (WDS) analysis, case study research is needed for testing or benchmarking optimisation strategies and newly developed software. However, data availability for the investigation of real cases is limited due to time and cost needed for data collection and model setup. We present a new algorithm that addresses this problem by generating WDSs from GIS using population density, housing density and elevation as input data. We show that the resulting WDSs are comparable to actual systems in terms of network properties and hydraulic performance. For example, comparing the pressure heads for an actual and a generated WDS results in pressure head differences of ±4 m or less for 75% of the supply area. Although elements like valves and pumps are not included, the new methodology can provide water distribution systems of varying levels of complexity (e.g., network layouts, connectivity, etc.) to allow testing design/optimisation algorithms on a large number of networks. The new approach can be used to estimate the construction costs of planned WDSs aimed at addressing population growth or at comparisons of different expansion strategies in growth corridors.
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Affiliation(s)
- Robert Sitzenfrei
- Corresponding author. Tel.: +43 512 507 6695; fax: +43 512 507 2911.
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