ISO 24527:2020

INTERNATIONAL ISO
STANDARD 24527
First edition
2020-04
Service activities relating to drinking
water supply, wastewater and
stormwater systems — Guidelines on
alternative drinking water service
provision during a crisis
Activités de service relatives aux systèmes d'alimentation en eau
potable, aux systèmes d'assainissement et aux systèmes de gestion des
eaux pluviales — Lignes directrices relatives à l'approvisionnement
alternatif en eau potable en cas de crise
Reference number
©
ISO 2020
© ISO 2020
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ii © ISO 2020 – All rights reserved

Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principles for alternative drinking water service provision . 5
4.1 General . 5
4.2 Alternative drinking water service approaches . 5
4.2.1 General. 5
4.2.2 Using the drinking water distribution network in a non-conventional manner . 5
4.2.3 Not using the drinking water distribution network . 5
5 Planning for alt ernative drinking water service provision . 6
5.1 General . 6
5.2 Pre-planning . 6
5.2.1 Establishing individual disruption scenarios . 6
5.2.2 Pre-planning in accordance with the disruption scenario . 6
5.3 Securing resources and planning for their mobilization . 7
6 Implementation of alternative drinking water service provision . 9
6.1 General . 9
6.2 Non-conventional methods for drinking water distribution network use . 9
6.2.1 General. 9
6.2.2 Distribution of drinking water by erection of standpipes . 9
6.2.3 Recharging of isolated drinking water distribution network assets by
water tankers . 9
6.2.4 Lowering the pressure at which drinking water is supplied .10
6.3 Methods not using the drinking water distribution network .10
6.3.1 General.10
6.3.2 Temporary point of distribution methods .10
6.3.3 Containerized drinking water .10
6.3.4 Via a fixed water resource .11
6.3.5 Via mobile water tankers or towed bowsers .11
7 Internal and external communications .11
7.1 General .11
7.2 Preparing stakeholders in advance of a crisis involving alternative drinking water
service provision .12
7.2.1 Tailored messaging .12
7.2.2 Preparing users .12
7.2.3 Preparing key stakeholders .12
7.3 Alternative drinking water service information during a crisis .12
7.3.1 General.12
7.3.2 How to communicate .12
7.3.3 What to communicate .14
8 Alternative drinking water service provision for users with special needs.14
Annex A (informative) Examples of layouts of, and assets deployment at, temporary points
of distribution .16
Annex B (informative) Containerized drinking water .19
Annex C (informative) Determining drinking water allocations .27
Annex D (informative) The logistics of alternative drinking water service provision .29
Annex E (informative) Modification of standard alternative drinking water service
processes to support users with special needs .34
Bibliography .35
iv © ISO 2020 – All rights reserved

Foreword
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iso/ foreword .html.
This document was prepared by Technical Committee ISO/TC 224, Service activities relating to drinking
water supply, wastewater and stormwater systems.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/ members .html.
Introduction
Drinking water is fundamental to life and its distribution is considered to be an essential service.
Drinking water supply relies on systems that can be subject to disruption from internal or external
factors including operational error, lack of rehabilitation, damage to the drinking water system,
malicious acts (e.g. vandalism, criminality or terrorism) and natural disasters (e.g. earthquakes, floods,
hurricanes or volcanic eruptions).
This document is intended for drinking water utilities that normally provide a service without
interruption through a drinking water distribution network. It provides guidelines for the effective
implementation of alternative drinking water service (ADWS) provision during extended periods of
disruption to drinking water supply.
In many cases, operational and organizational processes will exist within drinking water utilities to
deal with short periods of localized interruption to drinking water distribution. However, if the service
interruption exceeds the duration or extent of anticipated events, an interruption can escalate into a
crisis at local, regional or, exceptionally, national levels.
NOTE 1 For adequacy and consistency, guidance in this document typically assumes an operational response
at a crisis level. However, the guidelines are applicable for all levels of operational incidents requiring ADWS
deployment including normal business continuity preparedness and response.
NOTE 2 For guidance on the management of crises see ISO 24518 and ISO/TS 24520.
A significant water interruption (arising from quantity and/or quality issues) can impact public and
personal health and wellbeing, and economic performance. A prolonged interruption can progressively
threaten the coherence of the community served.
The roles of relevant authorities, responsible bodies, drinking water utilities and operators can differ
between and within countries and result in different minimum requirements for ADWS provision.
Nevertheless, it is generally recommended that such organizations recognize the importance of
uninterrupted drinking water distribution, even at times of crisis for the drinking water utility, for the
wellbeing of the community served.
Drinking water utilities are encouraged to reduce the risk of water supply interruption. This is
typically achieved by a combination of good planning, design, procurement, installation, operation and
maintenance of the drinking water assets. Such measures should include the provision of an ADWS for
users during a crisis.
It is also recommended that the drinking water utility's capability to provide
...