ISO/FDIS 20760-2

ISO/TC 282/SC 2/WG 1
Secretariat: SAC
Date: 2025-02-2708-12
Water reuse in urban areas — Guidelines for centralized water reuse
system —
Part 2:
Management of a centralized water reuse system
Réutilisation d'eau dans les zones urbaines de l'eau en milieu urbain — Lignes directrices concernant les
systèmes centralisés de réutilisation de l'eau — —
Partie 2: Gestion d'un système centralisé de réutilisation de l'eau
FDIS stage
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ii
Contents
Foreword . iv
Introduction . v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Overview of management issues of a centralized water reuse system . 2
4.1 General . 2
4.2 Water demand . 3
4.3 System components . 3
4.4 Possible models of the reclaimed water system and end-use needs . 3
5 Principles and methodology of reclaimed water management . 4
5.1 Principles . 4
5.2 Risk management . 4
6 Management of source water . 4
7 Management of reclaimed water treatment systems . 4
8 Management of reclaimed water storage systems . 5
9 Management of reclaimed water distribution systems . 6
9.1 General . 6
9.2 Delivery pressure and flow rate of reclaimed water . 6
9.3 Water quality in distribution systems . 6
9.4 Colour-coding, water signs and labels . 6
9.5 Backflow and cross-connection control . 7
9.6 System leakage and corrosion control . 7
9.7 Service connections. 7
10 Water quality monitoring . 7
10.1 General . 7
10.2 Baseline monitoring . 8
10.3 Validation monitoring . 8
10.4 Operational monitoring . 8
10.5 Verification monitoring . 9
11 Management of incidents and emergencies . 9
12 Supporting recommendations . 9
13 Review . 10
Bibliography . 11

iii
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out through
ISO technical committees. Each member body interested in a subject for which a technical committee has been
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The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types of
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ISO/IEC Directives, Part 2 (see www.iso.org/directives).
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Organization (WTO) principles in the Technical Barriers to Trade (TBT)), see
www.iso.org/iso/foreword.htmlthe following URL: .
This document was prepared by Technical Committee ISO/TC 282, Water reuse, Subcommittee SC 2, Water
reuse in urban areas.
This second edition cancels and replaces the first edition (ISO 20760-2:2017), which has been technically
revised.
The main changes are as follows:
— — updating theupdated example regarding water reuse management initiatives in the European Union;
— — updatingupdated information on the typical disinfection techniques;
— — addingadded information on the key performance indicators for typical treatment processes;
— — addingadded information regarding online data management.
A list of all parts in the ISO 20760 series can be found on the ISO website.
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.
iv
Introduction
With economic development, climate change and increases in population and rapid urbanization, water has
become a strategic resource especially in arid and semi-arid regions. Water shortages are considered as one
of the most serious threats to sustainable development of society. To address these shortages, reclaimed water
is increasingly being used to satisfy water demands and this strategy has proven useful in increasing the
reliability of long-term water supplies in many water-scarce areas.
The role of water reuse is growing for urban areas in many countries including landscape irrigation, industrial
uses, toilet and urinal flushing, firefighting and fire suppression, street cleaning, environmental and
recreational uses (ornamental water features, water bodies’ replenishment, etc.) and vehicle washing. These
centralized water reuse systems have been developed to the degree that they are now considered as an
effective component of urban water management and are used in many cities and countries.
The essential components of a centralized water reuse system include wastewater collection systems (sewers
and pumping stations), water source, a reclaimed water treatment system, reclaimed water storage, a
reclaimed water distribution system, and a water quality monitoring system. The management concepts and
principles are suggested to be implemented throughout the whole system, from the source water to the end
users. Each component should be characterized and managed with appropriate strategies.
This document provides management concepts and principles for centralized water reuse systems in urban
areas. It considers and addresses the critical issues or factors during management, which will facilitate water
authorities and reclaimed water providers or practitioners, or both, to conduct cost-effective approaches for
safe and reliable fit-for-purpose water reuse. For details on the design of a centralized water reuse system, see
ISO 20760-1. Additionally, for details on the design and management of decentralized or onsite water reuse
systems in urban areas, see ISO 23056.
v
DRAFT International Standard ISO/FDIS 20760-2:2025(en)

Water reuse in urban areas — Guidelines for centralized water reuse
system —
Part II: 2:
Management of a centralized water reuse system
1 Scope
This document provides guidelines for the management of centralized water reuse systems and water reuse
applications in urban areas.
This document addresses centralized water reuse systems in their entirety and is applicable to any water
reclamation system component (e.g. source water, treatment, storage, distribution, operation and
maintenance and monitoring).
This document provides:
— — principles and methodology of reclaimed water management;
— — management issues in each system component of a centralized water reuse system;
— — water quality monitoring;
— — specific aspects for consideration and emergency response.
This document excludes monitoring parameters and regulatory values (e.g. water quality limits) of a
centralized water reuse system.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitute
requirements of this document. For dated references, only the edition cited applies. For undated references,
the latest edition of the referenced document (including any amendments) applies.
ISO 20670, Water reuse — Vocabulary
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 20670apply20670 apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— — ISO Online browsing platform: available at https://www.iso.org/obp
— — IEC Electropedia: available at https://www.electropedia.org/
4 Overview of management issues of a centralized water reuse system
4.1 General
The system analysis and management of a centralized water reuse system should have an understanding of
the entire system, which generally includes several aspects:
a) a) water supply needs;
b) b) assessment of the reclaimed water system (e.g. environmental sustainability and health risk);
c) c) preventive maintenance measures for reclaimed water management;
d) d) operational procedures and process control;
e) e) verification of reclaimed water quality to ensure public health protection while providing
environmental benefits;
f) f) social and public aspects on water supply needs and the water quality needs;
g) g) incident and emergency management.
The management framework can be supplemented with supporting recommendations and should be
periodically reviewed and modified. The planning of review periods should take into account the influencing
technical and environmental factors. As the wastewater production of an area differs
...