ISO/FDIS 18998
(Main)Water reuse in urban areas — Guidelines for decentralized water reuse system — Management of a decentralized water reuse system
Water reuse in urban areas — Guidelines for decentralized water reuse system — Management of a decentralized water reuse system
This international standard will provide guidance for the management of urban decentralized water reuse system. The guide emphasizes the systematicness of the management of decentralized water reuse system and will include the management principles, management modes, management elements, technical route management and support management of decentralized water reuse system. This International Standard presents: (1) Preface; (2) Scope; (3) Normative references; (4) Terms and definitions; (5) Management overview; (6) Technical route management, including source water collection management, treatment process management, storage and distribution management and terminal utilization management; (7) Support management, including monitoring management, risk management, emergency management and participants management.
Titre manque
General Information
Standards Content (Sample)
FINAL DRAFT
International
Standard
ISO/TC 282/SC 2
Water reuse in urban areas —
Secretariat: SAC
Guidelines for decentralized water
Voting begins on:
reuse system — Management of a
2025-10-24
decentralized water reuse system
Voting terminates on:
2025-12-19
RECIPIENTS OF THIS DRAFT ARE INVITED TO SUBMIT,
WITH THEIR COMMENTS, NOTIFICATION OF ANY
RELEVANT PATENT RIGHTS OF WHICH THEY ARE AWARE
AND TO PROVIDE SUPPOR TING DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO
LOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT
INTERNATIONAL STANDARDS MAY ON OCCASION HAVE
TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL
TO BECOME STAN DARDS TO WHICH REFERENCE MAY BE
MADE IN NATIONAL REGULATIONS.
Reference number
FINAL DRAFT
International
Standard
ISO/TC 282/SC 2
Water reuse in urban areas —
Secretariat: SAC
Guidelines for decentralized water
Voting begins on:
reuse system — Management of a
decentralized water reuse system
Voting terminates on:
RECIPIENTS OF THIS DRAFT ARE INVITED TO SUBMIT,
WITH THEIR COMMENTS, NOTIFICATION OF ANY
RELEVANT PATENT RIGHTS OF WHICH THEY ARE AWARE
AND TO PROVIDE SUPPOR TING DOCUMENTATION.
© ISO 2025
IN ADDITION TO THEIR EVALUATION AS
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO
LOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
INTERNATIONAL STANDARDS MAY ON OCCASION HAVE
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL
or ISO’s member body in the country of the requester.
TO BECOME STAN DARDS TO WHICH REFERENCE MAY BE
MADE IN NATIONAL REGULATIONS.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland Reference number
ii
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Management models of decentralized water reuse systems . 1
4.1 General .1
4.2 Management models .3
4.2.1 Onsite systems management model.3
4.2.2 Cluster systems management model .3
4.2.3 Community systems management model .4
4.3 Management process .5
5 Management of source water . 6
6 Management of treatment processes for water reuse . 7
6.1 General .7
6.2 Selection of monitoring indicators .7
6.2.1 Principles of indicator selection .7
6.2.2 Indicator monitoring .8
6.3 Process adjustment .8
6.4 Operation and maintenance of equipment .8
7 Management of storage system . 9
8 Management of distribution system . 9
9 Management of end uses . . 9
9.1 Principles .9
9.2 Main items of end uses .10
10 Management of sludge treatment .11
10.1 General .11
10.2 Generation and collection .11
10.3 Selection and design .11
10.4 Monitoring and control .11
10.5 Safety and environmental measures .11
10.6 Quality control and evaluation .11
11 Management of monitoring .11
11.1 General .11
11.2 Baseline monitoring . . 12
11.3 Validation monitoring . 12
11.4 Operational monitoring . 12
11.5 Verification monitoring . 13
12 Management of incidents and emergencies . 14
13 Management of operations and maintenance staff .15
14 Review .15
Bibliography .16
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 established has the right to be represented on that committee. International organizations,
governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely
with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
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 ISO documents should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent
rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a)
patent(s) which may be required to implement this document. However, implementers are cautioned that
this may not represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO’s adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 282, Water reuse, Subcommittee SC 2, Water
reuse in urban areas.
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, population growth, and rapid urbanization continuing to shape
the world, water has become an increasingly important strategic resource, particularly in arid and semi-
arid regions. However, even in areas with abundant water resources, challenges such as water shortages
and seasonal water scarcity remain. Water scarcity is recognized as one of the most serious threats to
sustainable development. To address these challenges, an increasing number of communities are turning to
use reclaimed water to meet water needs. This approach has been shown to be effective in improving the
reliability of long-term water supply, particularly in areas where water is scarce.
While centralized water reuse facilities have been widely implemented under different ownership and
management structures, there is also a need to develop decentralized/onsite water reuse systems in cost-
effective and resource-efficient ways, which can improve flexibility and convenience. Decentralized water
reuse systems have emerged as an essential component of water management in many cities and countries.
These systems typically consist of source water collection, wastewater treatment facilities, storage and
distribution systems, and monitoring systems. Man
...
ISO/DISFDIS 18998:2025(en)
ISO/TC 282/SC 2/WG 4
Secretariat: SAC
Date: 2025-08-1810-09
Water reuse in urban areas — Guidelines for decentralized water
reuse system — Management of a decentralized water reuse system
FDIS stage
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication
may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying,
or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO
at the address below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: + 41 22 749 01 11
E-mail: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii
ISO/DISFDIS 18998:2025(en)
Contents
Foreword . iv
Introduction . v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Management models of decentralized water reuse systems . 1
4.1 General . 1
4.2 Management models . 3
4.3 Management process . 8
5 Management of source water . 9
6 Management of treatment processes for water reuse . 10
6.1 General . 10
6.2 Selection of monitoring indicators . 10
6.3 Process adjustment . 11
6.4 Operation and maintenance of equipment . 11
7 Management of storage system . 12
8 Management of distribution system . 12
9 Management of end uses . 13
9.1 Principles . 13
9.2 Main items of end uses . 13
10 Management of sludge treatment . 14
10.1 General . 14
10.2 Generation and collection . 14
10.3 Selection and design . 14
10.4 Monitoring and control . 15
10.5 Safety and environmental measures . 15
10.6 Quality control and evaluation . 15
11 Management of monitoring . 15
11.1 General . 15
11.2 Baseline monitoring . 15
11.3 Validation monitoring . 15
11.4 Operational monitoring . 16
11.5 Verification monitoring . 17
12 Management of incidents and emergencies . 19
13 Management of operations and maintenance staff . 20
14 Review . 20
Bibliography . 21
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
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
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
ISO documents should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent rights
in respect thereof. As of the date of publication of this document, ISO [had/had not] received notice of (a)
patent(s) which may be required to implement this document. However, implementers are cautioned that this
may not represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO'sISO’s adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 282, Water reuse, Subcommittee SC 2, Water
reuse in urban areas.
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
ISO/DISFDIS 18998:2025(en)
Introduction
With economic development, climate change, population growth, and rapid urbanization continuing to shape
the world, water has become an increasingly important strategic resource, particularly in arid and semi-arid
regions. However, even in areas with abundant water resources, challenges such as water shortages and
seasonal water scarcity remain. Water scarcity is recognized as one of the most serious threats to sustainable
development. To address these challenges, an increasing number of communities are turning to use reclaimed
water to meet water needs. This approach has been shown to be effective in improving the reliability of long-
term water supply, particularly in areas where water is scarce.
While centralized water reuse facilities have been widely implemented under different ownership and
management structures, there is also a need to develop decentralized/onsite water reuse systems in cost-
effective and resource-efficient ways, which can improve flexibility and convenience. Decentralized water
reuse systems have emerged as an essential component of water management in many cities and countries.
These systems typically consist of source water collection, wastewater treatment facilities, storage and
distribution systems, and monitoring systems. Management concepts and principles should be implemented
from source water to end users throughout the system, and appropriate strategies should be adopted for each
component.
This document provides management concepts and principles for decentralized water reuse systems in urban
areas, and it can be used by practitioners and regulatory authorities, who intend to implement management
concepts, principles, and supports on decentralized water reuse in a safe, reliable, and sustainable manner. It
considers and addresses key issues in the management process, which can help relevant practitioners and
users to adopt cost-effective methods to achieve safe, reliable, and appropriate reuse of reclaimed water. For
detailed information on the design of decentralized water reuse systems, refer to ISO 23056.
v
DRAFT International Standard ISO/DIS 18998:2025(en)
Water reuse in urban areas — Guidelines for decentralized water
reuse system — Management of a decentralized water reuse system
1 Scope
This document provides guidelines for the management of decentralized water reuse systems and water reuse
applications in urban areas.
This document addresses decentralized water reuse systems in their entirety and is applicable to any water
reuse systems component (e.g. reclaimed water, source water, treatment, storage, distribution, operation and
maintenance, and monitoring).
This document covers:
— — management of each system component of a decentralized water reuse system;
— — specific aspects for consideration and emergency response.
This document does not cover monitoring parameters and regulatory values of a decentralized 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 20670 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 Management models of decentralized water reuse systems
4.1 General
Effective management practices are indispensable for the successful reuse of treated wastewater in
decentralized water reuse systems. The management of decentralized water reuse systems should consider
the following aspects:
— — source water assessment;
— — system design;
— — location selection;
— — operations and maintenance;
— — regulatory compliance;
— — cost-benefit analysis and;
— — community engagement.
Decentralized water reuse management should align with utilization systems through various management
models, including onsite, cluster, and community models. Risk management and control should be highlighted
in decentralized water reuse systems. Aspects and specific points that should be considered in the
management of decentralized water reuse systems are shown in Table 1Table 1.
Table 1 — Considerations for management of decentralized water reuse systems
Primary aspects Contributing factors
— — Water quantity monitoring
— — Water quality testing
Water quality and quantity
— — Monitoring equipment
— — Equipment maintenance
— — Troubleshooting
— — Waste removal and disposal
Operations and maintenance
— — Leak detection and contamination control
— — System regular check and maintenance
— — Odour control
— — Operational costs
— — Capital cost
— — Sustainability
— — Tax policies
Economic impact
— — Revenue and risk
— — Reclaimed water pricing
— — System o
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.