Intermittent water supply systems and their resilience to COVID-19: IWA IWS SG survey

Abstract

There is limited information about the current state of intermittent water supply (IWS) systems at the global level. A survey was carried out by the Intermittent Water Supply Specialist Group of the International Water Association (IWA IWS SG) to better understand the current state of these systems and challenges that water companies may have faced under COVID-19 pandemic and to capture successful management strategies applied by water utilities. The survey consisted of three parts: (1) general information about IWS systems, (2) current state of IWS and (3) resilience of IWS under COVID-19 conditions, as well as some questions about potential interventions in order to improve system performance in general and under future uncertain conditions. The survey responses were evaluated based on the Safe & SuRe resilience framework, assessing measures of mitigation, adaptation, coping and learning, and exploring organisational and operational responses of IWS utilities. Infrastructure capacity and water resources availability were identified as the main causes of intermittency in most water distribution systems, while intermittent electricity was considered as the main external cause. Participants indicated that some risk assessment process was in place; however, COVID-19 has surpassed any provisions made to address the risks. Lessons learnt highlighted the importance of financial resources, e-infrastructure for efficient system operation and communication with consumers, and the critical role of international knowledge transfer and the sharing of best practice guidelines for improving resilience and transitioning towards continuous water supply.

Bacterial communities in a neotropical full-scale drinking water system including intermittent piped water supply, from sources to taps

“…In contrast, first flush samples averaged an HPC concentration of 4.3 × 10 4 MPN/100 mL (4.3 ± 2.8 × 10 4 MPN/100 mL) and were significantly higher than concentrations from stable IWS (Kruskal–Wallis, p < 0.001) which averaged 70 ± 109 MPN/100 mL and ranged from 5 to 300 MPN/100 mL. Other studies have also found a deterioration of water quality during first flush events when supply is restarted regardless of the duration of the stoppage; 15–17,64–66 although differences in water quality between first flush and stable supply may not be significant in all cases. 16…”

Nanoparticle-Enhanced PVDF Flat-Sheet Membranes for Seawater Desalination in Direct Contact Membrane Distillation

“…More often, consumers use potable water under restricted conditions where water rationing is implemented. Predominantly, access to safe drinking water is affected by poor financial reserves and inadequate infrastructure [ 5 , 7 ]. Rapid population growth, industrialization, and climate change threaten freshwater resources resulting in substantial water shortages.…”

An Operational Scheduling Framework for Tanker-Based Water Distribution Systems under Uncertainty

“…Provision of such a service is mainly via two main methods, namely, the piped water distribution network and tanker-based water supply systems. To this end, challenges related to water supply in urban areas include (i) low reliability of piped distribution system supply , and (ii) lack of full coverage by the piped water distribution network in peri-urban areas . Piped water supply being spatially and temporally uneven across the city, tanker-based water supply is one of the most prominent forms of alternative arrangements for water distribution in cities of various countries like India, Italy, Malaysia, Kenya, etc. − These tanker water distribution systems facilitate residents in peri-urban areas who are not connected to piped network infrastructure and also in urban areas where people are facing water shortages due to highly intermittent nature of piped distribution systems.…”