**3. Sustainable Water Resources Management (SWRM): Definitions, Guidelines, and Criteria**

#### *3.1. Definitions*

While the definition of sustainability was previously mentioned in Section 1.1, it is essential to clarify further definitions used within this paper—not least WRM. Firstly, WR can be defined as any shape or state of natural waters that exist on the planet, whether above (e.g., rainwater in clouds), on (e.g., oceans and rivers), or under the ground (e.g., GW), that has the potential to be used by humans [51]. Secondly, management can be defined simply as the way to manage something. In terms of WRM, these definitions pertain to the supply of and demand for water and all matters related to them.

Furthermore, it can be considered that the definition of WR includes both the natural freshwater and saltwater that usually react to or are affected by the processes of the hydrological cycle and other species' activities. Humans are one of the species that can impact WR in their use of them, but what does it mean to make this process sustainable? Gleick et al. [52] defined sustainable water use as:

*"the use of water that supports the ability of human society to endure and flourish into the indefinite future without undermining the integrity of the hydrological cycle or the ecological systems that depend on it."* [52] (p. 24)

However, humans have the most significant impact on the environment in general and on WR in particular due to their activities [19,53,54]. These impacts on WR are expected to expand in the future and cause more uncertainty in terms of water availability, more extreme weather events of droughts and floods, and quicker evaporation of surface water resources [53]. Hence, it is important to prepare carefully for these risks before they happen or increase to improve the sustainable management of WR systems.

Accordingly, the three definitions for the three terms (i.e., sustainability, water resources, and management) can be combined to present a possible explanation for SWRM. The function of such a definition is to help stakeholders from different backgrounds understand the target in a simple way, which would assist in the communication process, thereby gaining their trust and cooperation.

Pertinently to this matter and its purpose, the term integrated water resources management (IWRM) is defined as:

*"a process which promotes the coordinated development and management of water, land and related resources, in order to maximise the resultant economic and social welfare in an equitable manner without compromising the sustainability of vital ecosystems".* [23] (p. 1)

Although the previous definition is widely known and broadly accepted by the scientific community, the understandable main aim is to maximize the benefits to the economy and society without harming the ecosystem or the environment. Meanwhile, it can be argued that the purpose of sustainability is slightly different, being more about obtaining the best result (i.e., optimizing) for all three aspects (i.e., economy, society, and environment) in as balanced a way as possible.

Therefore, the suggested definition for SWRM used in this paper is "*to ensure that the current management of water resources meets the need of the present generation in a way that balances between social*, *economic*, *and environmental factors avoiding negatively impacting future generations' capability to meet their water needs*", accepting that future needs are not always easy to identify and require a range of foresight methods to predict. This definition requires a breakdown into several objectives or components that constitute indicators and sub-indicators to measure the performance of SWRM.

#### *3.2. Guidelines for the Development of the SWRM Framework*

Sustainability frameworks and their indicators, in general, could (and should) have different interpretations based on the perspective, context, and local conditions they are used for. For example, frameworks assigned for business or construction *per se* would be different than those for WRM. Indeed, each sector should have specific guidelines and criteria for any suggested indicator that matched its context [44,55].

First of all, the consideration and linkage of the three dimensions of sustainability (i.e., environmental, economic, and social) [56], in addition to the technical side in the criteria overall, are crucial to handling the complexity and uncertainty of water-related issues [57]. Hence, a sustainable system would not only facilitate the management of the infrastructure of water utilities with the supply and demand sides, but would also assure integration and fairness among the previously mentioned three core areas. Thus, it is essential in the developing stage of an SWRM framework to check whether any suggested indicator belongs (or not) to one of these four categories (i.e., technical or physical, environmental, economic, and social) before considering it.

The second general guideline can be elicited from one of the Dublin principles [28] (i.e., the third), which emphasizes the importance of a participatory approach for any development for WR. Thus, the involvement of stakeholders in developing an SWRM-AF, or at least the process of indicator selection, is necessary.

Another guideline is that the number of indicators should be appropriate. In other words, they should not be too numerous, since this would complicate the process of application and interpretation [58,59] and challenge the capacity of the financial and human resources in collection and analysis. Conversely, too small a number could result in

inaccurate conclusions that would lead to weak policy decisions—not least because they would be based on inadequate data [44]. Hence, it is instrumental during the selection process to focus on just the right number of indicators whose details (i.e., data) are available, unambiguous, and comprehensive. Nevertheless, following the above guidelines as a first stage would require more specific criteria for the selection process of each indicator, as outlined in Section 3.3.

#### *3.3. Criteria for Selection of SWRM Indicators*

Specific criteria must be considered in order to select appropriate indicators for assessing SWRM-AF. One of these criteria is that these sustainable indicators should (1) work as a set; (2) be both simple and clear, and (3) contain sufficient information to help decisionmakers provide efficient actions [60].

Moreover, Bell and Morse [61] identified other criteria as conditions for selecting indicators. Indicators must:


Therefore, sustainability indicators should be filtered by the previous criteria to decide whether they are applicable and relevant to the system and whether they fit its definition. Additionally, data availability is significant; data must be authentic and from open sources, allowing access for all stakeholders. Furthermore, the United Nations [59] suggested additional selection criteria for sustainable development indicators, some of which could benefit the development of the SWRM framework, as follows:


Thus, it can be considered that any indicator should have specific features to be considered, such as being measurable, understandable, conceptual, and adaptable based on the function for which it is used.

Next, in Section 4, a brief overview of the main elements of the indicator-based assessment framework or index is outlined and briefly illustrated.

### **4. Main Elements of an Indicator-Based Assessment Framework**

Before establishing or developing any assessment framework, it is vital to recognize and identify its main pillars. This process would ensure that the framework or index would be built clearly on a solid foundation. Therefore, the seven main elements of the indicator-based assessment framework, expressed explicitly and implicitly based on the literature analysis, are presented briefly below.

Overall, it can be said that any sustainability framework (or index) is constituted of several key parts: (1) a set of headline categories (components); (2) a set of underpinning indicators for each component, and (3) a set of second-order and possibly third-order sub-indicators [43]. To illustrate, a visual example for one of the SWRM-AFs included in this review (i.e., West Java Water Sustainability Index (WJWSI)- See Section 5.1) is presented in Figure 2, where the components are represented by the blue boxes, the indicators by the green ones, and the sub-indicators by the orange boxes.

**Figure 2.** A visual example of the main parts that form an index/framework.

It can be observed that the index in Figure 2 is in a hierarchy shape, where the aggregating direction is a bottom-up process. A particular calculation method (i.e., rescaling or normalization) to have an equivalent value for each indicator and sub-indicator would be applied. Then, the aggregation and the weight of the output value of each sub-indicator would produce the indicator value. The same process is applicable for the resultant values of indicators and components in obtaining the final value of the index (i.e., the top grey box in Figure 2).

#### *4.1. Indicator*

The first element in forming an assessment framework or index is the indicator itself, which has the feature of being able to:


At the same time, a question might arise about what is meant by an indicator and what is the purpose of using it? Indicators present data about the case of a phenomenon [56], used mainly to measure/assess progress toward sustainability [62]. Moreover, indicators can reveal how countries (or regions) are coping with internal and external goals (e.g., SDGs) and conditions in terms of their sustainability obligations [60].

Indicators and sub-indicators are often objective and quantitative—representing a quantity or change based on metrics (e.g., water leakage rate [%], litres of water per person [l/p]). They may also include other aspects, such as area (e.g., [l/m2]) or time periods [l/p/d] [l/p/yr]). On the other hand, they can be qualitative and subjective—dealing with cases that cannot be measured by a number, such as opinions, which differ from one person to another [44]. For example, they may be elicited by such questions as "How happy are you with your water provider (5 being very happy and 0 being very unhappy)"? However, in several SWRM frameworks in the literature, the value of a qualitative indicator or sub-indicator is converted into a number based on a pre-defined conditions or criteria to simplify the aggregation process, enabling the calculation of a final equivalent score for each component [63–65]. In general, combining the two types or classifications of indicators in the SWRM frameworks is not uncommon [66], although using only one or the other is more popular [63,65,67,68].
