*6.1. Existing SWRM-AFs and Their Applicability for ASAR*

The review has helped identify six key requirements that a framework would need in order for it to be considered appropriate for application in ASAR. In other words, they should:


With this in mind, Table 4 provides a synthesis of the analysis to evaluate (by way of grading) the 19 frameworks, including those from the systematic review and the previous two SWRM-AFs found in the grey literature. All of the checking aspects are based on the six requirements mentioned above. The first three aspects (i.e., 1 to 3) are considered general but essential for inclusion in any SWRM-AF. The last three aspects (i.e., 4 to 6) are specific and considered vital to any SWRM-AF for ASAR. In Table 4, one point was assigned for each aspect included—based on its existence, except for the participatory approach, where a point was equally divided between the selection and weighting. Additionally, half of the maximum point was given if the aspect was either partially fulfilled or partially existed. This meant a maximum value of 6 could be achieved where a framework met all six criteria fully.


**Table 4.** Evaluation of the applicability of each SWRM-AF for ASAR.


**Table 4.** *Cont.*

Table 4 shows that the highest total points was 4 out of 6, found in three frameworks (i.e., WPI, AWSI, and ADWI). While two of these frameworks were developed mainly for ASAR (i.e., AWSI and ADWI), there were some general requirements identifiable by a zero in the respective columns. In other words, this research showed that there is no SWRM-AF that could be considered fully fit-for-purpose for application in ASAR. Hence, steps should be taken to address this gap in knowledge (See Section 6.3).

#### *6.2. Shortfalls of this Research*

This review paper goes some way towards filling the gap in knowledge with respect to identifying whether an SWRM-AF for ASAR exists. However, it should be noted that the review was restricted to two well-known academic databases (i.e., Scopus and Engineering Village) in addition to the search terms and filtering process adopted herein. Broadening the review to other databases (e.g., Google Scholar and Research Gate, to name just two) may have identified more literature (including grey literature) beyond the two most applicable papers found. In addition, this research was very much focused on the derivation of the frameworks themselves, and not on the detailing (and usefulness) of individual indicators or the data availability enabling the actual measurement of their values. Hence, whilst the need for a new framework was identified by this review, more stages of research are required during its derivation (See Section 6.3).

#### *6.3. Next Stage of Research*

The next area of research will seek to develop a SWRM-AF for ASAR that satisfies all six aspects outlined in Section 6.1 In order to ensure it is both practical and meaningful for application, a conceptual framework for ASAR will be developed. This will involve some key steps:


#### **7. Conclusions**

The sustainability of water supply to match proper demand is crucial for any future planning for the WRM system. This strategy became more significant in areas with limited WR and located in ASAR with challenging water conditions. During the last few decades, many scientific meetings and recommendations were conducted and presented to tackle the WRM issues, such as the Brundtland's definition, the Dublin principles, and the IWRM definition and principles. These efforts were the foundation for introducing guidance and criteria that led to the creation of several SWRM-Afs, such as those manifested above. However, it is essential to remember that sustainability does not mean focusing only on one pillar. Attaining a balance between the three pillars (i.e., environmental, social, economic) would generate the best results. This consideration should be accounted for during the development process of any tool that aims to improve and monitor sustainability progress. One of these tools is the indicator-based framework for assessing sustainability. Therefore, having specific and clear SWRM-AF to measure the level of SWRM would undoubtedly help improve the longevity of such vital resources.

Whilst many SWRM-AFs were developed for this purpose in the past, such as those described briefly in this review, it has been shown that they are insufficient to assess some ASAR. Moreover, even where frameworks have been developed specifically for ASAR, many shortfalls exist. That said, this review helps recognize the primary elements required to establish this type of framework. Moreover, detailed investigation and comparison among SWRM-AFs have helped identify similarities, differences, and limitations/knowledge gaps. As such, several recommendations are suggested based on the results of this review:


Therefore, a conceptual SWRM-AF for ASAR is recommended to tackle this issue, and its development is currently underway.

**Author Contributions:** Conceptualization, B.S.A.; methodology, B.S.A.; investigation, B.S.A.; resources, B.S.A.; data curation, B.S.A.; writing—original draft preparation, B.S.A.; writing—review and editing, B.S.A., D.V.L.H., and S.S.; visualization, B.S.A.; supervision, D.V.L.H. and S.S.; project administration, D.V.L.H. All authors have read and agreed to the published version of the manuscript.

**Funding:** D.V.L.H. received the financial support of the UK EPSRC under grant EP/J017698/1 (Transforming the Engineering of Cities to Deliver Societal and Planetary Wellbeing, known as Livable Cities) and EP/P002021 (From Citizen to Co-innovator, from City Council to Facilitator: Integrating Urban Systems to Provide Better Outcomes for People, known as Urban Living Birmingham).

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Not applicable.

**Acknowledgments:** B.S.A. gratefully acknowledges the financial support of Qassim University in Saudi Arabia given to him during his doctoral studies.

**Conflicts of Interest:** The authors declare no conflict of interest.
