scholarly journals Water quality trend analysis in a citywide water distribution system

2021 ◽  
Author(s):  
Keya Chowdhury ◽  
Aysha Akter
Keyword(s):  
Water Quality ◽  
Distribution System ◽  
Water Distribution ◽  
Oxygen Demand ◽  
Quality Parameters ◽  
Water Quality Parameters ◽  
Residual Chlorine ◽  
Secondary Source ◽  
Pipe Material ◽  
Rapid Urbanization

Abstract Rapid urbanization poses challenges to meet the increased water supply demands. Apart from the quantity, the distributed water quality often fails to meet the permissible level. This study aimed to conduct a citywide spatio-temporal variation of water quality parameters. Water sampling points were selected by applying the Analytical Hierarchical Process (AHP) technique using ArcGIS considering pipe leakage, source water quality, pipe age, and pipe materials. The Chattogram city comprises 397 km of pipes; pipe material distribution shows 71.28% PVC, 20.94% asbestos, 5.16% mild steel, 2.17% ductile, and 0.45% cast iron. The citywide pipe network was established in 1963; 20.87% of pipes aged over 30 years, 15.07% 20–30 years, 26.38% 10–20 years, and 37.68% pipelines are relatively new, i.e., within 0–10 years. Eight water quality parameters, i.e., pH, temperature, turbidity, biochemical oxygen demand after five days (BOD5), total coliform, fecal coliform, chloride, and residual chlorine, were collected from the secondary source cross-checked by field survey. Computation of the Water Quality Index (WQI) was interpolated using Inverse Distance Weighted (IDW) method to generate a WQI map. Thus, this study could be a basis to improve the treatment system and proper distribution network maintenance.

scholarly journals Assessment of probable causes of chlorine decay in water distribution systems of Gaborone city, Botswana

Water SA ◽  
2019 ◽  
Vol 45 (2 April) ◽  
Author(s):  
Denis Nono ◽  
Phillimon T Odirile ◽  
Innocent Basupi ◽  
Bhagabat P Parida
Keyword(s):  
Water Quality ◽  
Distribution System ◽  
Distribution Systems ◽  
Water Distribution ◽  
Inorganic Compounds ◽  
Quality Parameters ◽  
Water Quality Parameters ◽  
Biofilm Growth ◽  
Reaction Rate Constants ◽  
Chlorine Decay

Assessment of probable causes of chlorine decay in water distribution systems of Gaborone city, Botswana Gaborone city water distribution system (GCWDS) is rapidly expanding and has been faced with the major problems of high water losses due to leakage, water shortages due to drought and inadequate chlorine residuals at remote areas of the network. This study investigated the probable causes of chlorine decay, due to pipe wall conditions and distribution system water quality in the GCWDS. An experimental approach, which applied a pipe-loop network model to estimate biofilm growth and chlorine reaction rate constants, was used to analyse pipe wall chlorine decay. Also, effects of key water quality parameters on chlorine decay were analysed. The water quality parameters considered were: natural organic matter (measured by total organic carbon, TOC; dissolved organic carbon, DOC; and ultraviolet absorbance at wavelength 254, UVA-254, as surrogates), inorganic compounds (iron and manganese) and heterotrophic plate count (HPC). Samples were collected from selected locations in the GCWDS for analysis of water quality parameters. The results of biofilm growth and chlorine reaction rate constants revealed that chlorine decay was higher in pipe walls than in the bulk of water in the GCWDS. The analysis of key water quality parameters revealed the presence of TOC, DOC and significant levels of organics (measured by UVA-254), which suggests that organic compounds contributed to chlorine decay in the GCWDS. However, low amounts of iron and manganese (< 0.3 mg/L) indicated that inorganic compounds may have had insignificant contributions to chlorine decay. The knowledge gained on chlorine decay would be useful for improving water treatment and network operating conditions so that appropriate chlorine residuals are maintained to protect the network from the risks of poor water quality that may occur due to the aforementioned problems.

scholarly journals Investigating the occurrence of algae in the drinking water supply system of Harare, Zimbabwe

2020 ◽  
Vol 10 (2) ◽  
pp. 179-190
Author(s):  
Pardon Dandadzi ◽  
Zvikomborero Hoko ◽  
Tamuka Nhiwatiwa
Keyword(s):  
Water Quality ◽  
Drinking Water ◽  
Water Treatment ◽  
Water Supply ◽  
Distribution System ◽  
Quality Parameters ◽  
Supply System ◽  
Water Quality Parameters ◽  
Residual Chlorine ◽  
Raw Water

Abstract This study assessed the quality of drinking water in the water supply system for the City of Harare (Zimbabwe) by investigating the occurrence of algae and other water quality parameters that affect its growth. At Morton Jaffray Water Treatment Works (MJWTWs), samples were collected from the raw water inlet and treated water outlet points. In the distribution system, samples were collected from selected sites and grouped into four zones (1, 2, 3 and 4). The algal taxonomic groups that were found in both raw and treated water comprised of Cyanophyceae, Chlorophyceae, Bacillariophyceae, Euglenophyceae and Dinophyceae. It was found out that Microcystis aeruginosa followed by Anabaena were the most abundant species in both raw water and in the distribution system. All measured water quality parameters were within the Standards Association of Zimbabwe and WHO guideline values except for chlorine which had an average residual chlorine concentration that was lower than the WHO recommended lower value of 0.2 mg/L in parts of Zone 2. Morton Jaffray Water Treatment Works does not completely remove algae, and there is a carry-over of algae into the distribution system. Boosting of chlorine is recommended for Zone 2 that had residual chlorine less than the WHO minimum threshold of 0.2 mg/L.

scholarly journals Cladoceran abundance in relation to water quality parameters of Chakki Talab, Bodhan, Telangana

2018 ◽  
Vol 8 (01) ◽  
Author(s):  
Vasudha Lingampally ◽  
V.R. Solanki ◽  
D. L. Anuradha ◽  
Sabita Raja
Keyword(s):  
Water Quality ◽  
Dissolved Oxygen ◽  
Oxygen Demand ◽  
Total Dissolved Solids ◽  
Quality Parameters ◽  
Biological Oxygen Demand ◽  
Water Quality Parameters ◽  
Total Alkalinity ◽  
Total Hardness ◽  
One Year

In the present study an attempt has been made to evaluate water quality and related density of Cladocerans for a period of one year, October 2015 to September 2016. Water quality parameters such as temperature, PH, total dissolved solids, dissolved oxygen, biological oxygen demand, total alkalinity, total hardness, chlorides, phosphates, and nitrates are presented here to relate with the abundance of Cladocerans. The Cladoceran abundance reflects the eutrophic nature of the Chakki talab.

scholarly journals The Interaction between the Bulking Water and Pipe Surface and Their Correlations in Water Distribution System

2018 ◽  
Vol 7 (2) ◽  
pp. 83
Author(s):  
Ruilian Li ◽  
Ming-qing Feng ◽  
Xiao-hui Bai
Keyword(s):  
Water Quality ◽  
Distribution System ◽  
Water Distribution ◽  
Water Distribution System ◽  
Tap Water ◽  
Close Relation ◽  
Quality Parameters ◽  
Iron Corrosion ◽  
Pipe Surface ◽  
Pipe Water

The pipelines corrosion can result discolor and particle increase in tap water and the complaints from the consumers. It also has the economic and hydraulic impacts for the replacement of broken pipes and fouling of corroded pipes. This paper aimed to investigate the effect of processed drinking water on metal pipe corrosion in water distribution system and the relations between the bulking water quality and pipe corrosion. It was found that there is a close relation between iron corrosion and water quality parameters in water distribution pipelines. It was shown that lower pH and alkalinity can increase the corrosion rate, while higher chlorides and sulfate may cause pitting corrosion. DOC in pipe water would be beneficial for microbial induced corrosion.

scholarly journals Implementation of Long-Short Term Memory Neural Network (LSTM) for Predicting The Water Quality Parameters in Sungai Selangor

2021 ◽  
Vol 6 (4) ◽  
pp. 40-49
Author(s):  
Nur Natasya Mohd Anuar ◽  
Nur Fatihah Fauzi ◽  
Huda Zuhrah Ab Halim ◽  
Nur Izzati Khairudin ◽  
Nurizatul Syarfinas Ahmad Bakhtiar ◽  
...  
Keyword(s):  
Water Quality ◽  
Short Term Memory ◽  
Oxygen Demand ◽  
Quality Parameters ◽  
Water Quality Parameters ◽  
Short Term ◽  
Term Memory ◽  
Quality Of Water ◽  
Long Short Term Memory

Predictions of future events must be factored into decision-making. Predictions of water quality are critical to assist authorities in making operational, management, and strategic decisions to keep the quality of water supply monitored under specific criteria. Taking advantage of the good performance of long short-term memory (LSTM) deep neural networks in time-series prediction, the purpose of this paper is to develop and train a Long-Short Term Memory (LSTM) Neural Network to predict water quality parameters in the Selangor River. The primary goal of this study is to predict five (5) water quality parameters in the Selangor River, namely Biochemical Oxygen Demand (BOD), Ammonia Nitrogen (NH3-N), Chemical Oxygen Demand (COD), pH, and Dissolved Oxygen (DO), using secondary data from different monitoring stations along the river basin. The accuracy of this method was then measured using RMSE as the forecast measure. The results show that by using the Power of Hydrogen (pH), the dataset yielded the lowest RMSE value, with a minimum of 0.2106 at station 004 and a maximum of 1.2587 at station 001. The results of the study indicate that the predicted values of the model and the actual values were in good agreement and revealed the future developing trend of water quality parameters, showing the feasibility and effectiveness of using LSTM deep neural networks to predict the quality of water parameters.

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