Abstract
To maintain desirable residual chlorine for a groundwater source, optimizing the chlorine dose in small- to medium-sized water distribution systems (SM-WDS) is a daunting task in developing countries. Mostly, operators add a random chlorine dose without recognizing the smaller size of their distribution network. In this research, a modelling framework for optimizing chlorine dose in SM-WDS is developed. In order to evaluate its practicality, the proposed framework has been applied in a case study of a residential neighbourhood in Lahore (Pakistan) with a small network spanning over 0.35 km 2 . Three datasets for residual chlorine were monitored at 6 locations spread over the study area. EPANET 2.0 software was used for hydraulic and residual chorine modelling. The bulk decay coefficient (K b ) was determined in the laboratory, whereas the wall decay coefficient (K w ) was estimated by calibrating the simulation results with the residual chlorine determined in the field. Based on the calibrated EPANET simulations, a fuzzy rule-based model was developed for pragmatic application of the proposed framework. Scenario analyses for different situations have also been carried out for achieving residual chlorine required at the consumer end. This exercise revealed that much lower chlorine doses than the existing practice can generate detectable chlorine residuals. Moreover, the model can be used to deal with emergency situations, which may arise in developing countries due to viral outbreaks and cross-contamination events in SM-WDS. Keywords : small- to- medium-sized water distribution systems, residual chlorine modelling, water quality, chlorine decay coefficients, fuzzy rule-based modelling, EPANET
Highlights
Water service providers must practise disinfection before supplying water to consumers to prevent the outbreak of waterborne infectious diseases (Clark, 1998)
The results showed that an initial chlorine dose of 0.3 mg∙l−1 would be sufficient to maintain a residual close to 0.1 mg∙l−1
The methodology used in this research work can be applied to the distribution networks to maintain a desirable residual of 0.1 mg∙l-1 at all of the network nodes with an optimum chlorine dose
Summary
Water service providers must practise disinfection before supplying water to consumers to prevent the outbreak of waterborne infectious diseases (Clark, 1998). Bacteriological contamination of water is the major contributor to waterborne diseases. Millions of such cases occur annually in developing countries, including Pakistan (Haider et al, 2014; WHO, 2004). In Lahore alone, 10 000 people die annually due to the drinking of bacteriologicallycontaminated water (PCRWR, 2002). Eighty per cent (80%) of all illnesses in developing countries are linked to poor water quality and sanitation conditions (e.g., cholera, typhoid, hepatitis, dysentery, guinea worm infections, etc.) (PCRWR, 2007). The major reasons for this contamination include: (i) poorly maintained/ leaking pipe networks, (ii) laying of water supply pipelines parallel to or beneath sewers, and (iii) groundwater contamination due to disposal of untreated sewage into the water bodies which recharge the nearby water wells (Haydar and Qasim, 2013)
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
