Chlorine degradation in continuous and intermittent drinking water supply networks

ABSTRACT

Chlorine is a widely used disinfectant in developing countries due to its efficiency and affordability. Millions of people in these countries receive water intermittently through piped networks. However, very little is known about chlorine decay in intermittent networks. In this work, field chlorine decay measurements were carried out in adjoining continuous and intermittent networks. Hydraulic modelling was done to determine the water velocity in networks using EPANET. Overall chlorine decay rates were estimated using field measurements and showed a good first-order fit. Decay rates in continuous and intermittent networks were compared, considering the influence of pipe velocity, material and diameter. The average overall decay rate for ductile and cast-iron pipes in intermittent network (1.7 $h{r}^{-1}$) was 1.5 times higher than that in continuous network (1.1 $h{r}^{-1}$). These results indicate that intermittency has a long-term effect on the overall chlorine decay in supply networks and its implications are discussed in this study.

KEYWORDS:

• Chlorine decay
• intermittent water supply
• continuous water supply
• water quality
• water distribution network

Acknowledgements

This work was supported by the IMPRINT initiative of Ministry of Human Resource & Development and Ministry of Housing and Urban Affairs, Govt of India [Project code: 5786 and Sanction No: F.No.3-18/2015-TS-TS.I.]. We would also like to express our gratitude to BWSSB for sharing crucial data and providing the study team with necessary manpower and authorization.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data Availability

All data, models, and code generated or used during the study appear in the submitted article. All of the data is accessible at following GitHub repository:

https://github.com/ruchav93/Chlorine-Attenuation-in-Continuous-and-Intermittent-Drinking-water-Supply-Networks

Supplementary material

Supplemental data for this article can be accessed https://doi.org/10.1080/1573062X.2022.2139275

Notes

1. Micro imurities include: inorganic compounds: metals (Fe, As, Mn, Zn, Ca, Na, K, Mg, Pb, Cd), nonmetals (Br, I, F), anionic compounds (So4, No2, No3, Po4, Co3, Hco3,CN), gasses (NH3, Co2, O2, H2S), Compounds: Calcium and Magnesium salts, Sodium salts, Silicates, Chlorides, Aluminum phosphate. Organic compounds: Acids: Humic, Fulvic, Alkyl monocarboxylic, dicarboxylic, aromatic, Proteins, aromatic amines, Alkyl amines, amino acids, Purines, Pyrimidines, Phenols, tannin, hydrocarbons, aldehydes, ketones, methyl ketones, alkyl alcohols, Hydroxy acids, sugars, Carbohydrates, cellulose)

Additional information

Funding

This work was supported by the Ministry of Housing and Urban Affairs [F.No.3-18/2015-TS-TS.I.].