=Paper=
{{Paper
|id=Vol-1944/paper5
|storemode=property
|title=Applying Tropos4AS to Water Security Domain: Recycled Water System Case Study
|pdfUrl=https://ceur-ws.org/Vol-1944/paper5.pdf
|volume=Vol-1944
|authors=Safa Al Sadi,Layla Saleh,Davor Svetinovic
}}
==Applying Tropos4AS to Water Security Domain: Recycled Water System Case Study==
https://ceur-ws.org/Vol-1944/paper5.pdf
Applying Tropos4AS to Water Security Domain:
Recycled Water System Case Study
Safa Al Sadi, Layla Saleh Davor Svetinovic
Engineering Systems and Management Electrical Engineering and Computer Science
Masdar Institute of Science and Technology Masdar Institute of Science and Technology
Abu Dhabi, UAE Abu Dhabi, UAE
Email: {salsadi,lsaleh}@masdar.ac.ae Email: dsvetinovic@masdar.ac.ae
Abstract—In this study, we elicit and specify a goal model for the software engineer capturing, detailing and analyzing at the
the recycled water system of Abu Dhabi Emirate, along with the design stage the precise knowledge and decision measures that
constraints and strategies defined within the system boundary. will guide self-adaptation at run-time. Its technique brings
The preliminary results are evaluated using Systems Dynamics
approach by modeling and simulating the goals and require- the high level requirements, in the form of goal-models, to
ments defined using Tropos for Adaptive Systems (Tropos4AS) operation time, allowing the system to reach their satisfaction,
method. System Dynamics methodology allows investigation of to reflect upon them and to guide its behavior according to
the interactions between goals and the evaluation of the results. them [4].
This paper demonstrates preliminary evaluation of the System Having a rigorous model helps generating accurate forecasts
Dynamics ability in validating requirements engineering models.
Moreover, the linking of System Dynamics and Troposa4As is thus facilitating the effective planning and decisions making.
found promising since it seems it can improve the collaboration Therefore, this study aims to use a Tropos4AS to specify goal
between goals of different stakeholders for better planning, models, with the assistance of System Dynamics approach,
by considering the prioritized goals resulting from the hybrid that characterizes the recycled water system of Abu Dhabi
analysis. Emirate. The paper presents related work, research method,
Index Terms—goal-oriented requirements engineering, Tro-
pos4AS, system dynamics, water security
models development, results and evaluation.
II. BACKGROUND AND R ELATED W ORK
I. I NTRODUCTION A. Requirements Engineering
Significant research has been devoted to the water scarcity GORE methods from RE provide a systematic approach for
issue due to its importance and the impact that it could extracting, evaluating, analyzing, modeling and determining
create in hindering the sustainable development [1], [2]. software requirements. These approaches are built based on
Sustainability of water resources is considered as critical to certain fundamental concepts and principles, they focus on the
sustainable development in energy, food, health, education, needs of the stakeholders and express their requests in a natural
etc., especially with the population growth, climate change way, concentrating on their requirements and objectives, rather
and other uncertainties. than how to meet them [5], [6]. The main idea of goal models
In fact, managing water resources efficiently is a necessity, consists of developing a graph presenting all goals with their
and the potential of recycled water resource to improve the connections: how higher-level goals are refined into lower-
water system could be tremendous. In this context, many level ones and, contrariwise, how lower-level goals contribute
methods could be used to develop this complex system such to higher-level one, where the goal is defined as a statement of
as optimization, system dynamics, system modeling language, intent that the system should realize and accomplish through
etc. However, these methods should start by precisely specify- the collaboration of its different components [7]. Thus, a goal
ing the goals and requirements as a critical step towards taking model helps the engineers to distinguish the best solution from
correct decisions where any mistake could lead to huge losses. a set of alternatives by studying how those different solutions
In order to develop an efficient system, we need to have a clear satisfy and improve the quality of the requirements.
understanding of its main goal and its operation. Basically, Numerous GORE languages and approaches are available
this involves a complex process of identifying, recognizing and in literature (e.g., Keep All Objectives Satisfied (KAOS),
deciding on the system’s goals, requirements and functionality. i*, Security Quality RE (SQUARE), Tropos, etc.) KAOS
Requirement Engineering (RE) consists of analyzing and is a GORE approach initially applied by systems analysts
outlining the set of activities that are essential for structuring to satisfy the requirements through the achievement of the
and constructing a system where the functionality and the goals [8]. This method is initially considered for applica-
outcome meet the stakeholders requirements [3]. Tropos for tion in “knowledge acquisition in automated specification,”
Adaptive Systems (Tropos4AS), an extension to Tropos, is it enables to build a whole comprehensive model using a
one of the Goal-Oriented RE (GORE) approaches that helps goal tree structure with parent goals and sub-goals under the
responsibility of agents, such as, companies, government, and by the fact that it has the potential to predict a closer demand
nongovernmental organizations [9]. In addition, it discusses forecasts to reality since it is based on a historical calibrated
the fundamental activities of the RE process, which are at data [12]. The applications of System Dynamics in the water
the first stage elicitation, analysis, validation, negotiation, and field are abundant. Example of applications [13]: integrated
at the second stage documentation and management [10]. On water resources management to address complex issues in
the other hand, KAOS has some drawbacks too; this approach water planning and management, forecasting demand, and
does not support informally or imprecisely defined soft goals studying the effect of different government subsidy policies on
[9] and it lacks the description of system’s scenarios which is water use. The simulation software used for the development
an essential task for engineers to understand the sequences of of System Dynamics models is called Vensim PLE. This
the system and the constraints that are present in the system. software allows for data calibration, optimization, sensitivity
The Tropos approach, is considered as an agent-oriented analysis including Monte Carlo Simulation, as well as discrete
software engineering (AOSE) approach that covers the entire decision analysis.
software or system development process. This methodology is
based on two main ideas: firstly, the concept of agent and all C. Recycled Water Sector in the Emirate of Abu Dhabi
the related notions, such as goals and plans that are used in all
stages of the system development, from the early investigations Basically, the water supply sources in the Emirate of Abu
and analysis down to the actual application. Secondly, Tropos Dhabi have not witnessed a noticeable change since 2009
concept covers the very early stages of requirements analysis, [14], and they are divided into 3 groups, groundwater with
consequently allowing for a profound understanding of the 63%, desalinated water with 28% and recycled water with
environment where the software will operate [11]. Tropos 9%, of the total water supply in the emirate [15]. Abu Dhabi
methodology spans into four phases: early requirements, late Water and Electricity Company (ADWEC) handles the desali-
requirements, architectural design and detailed design. Notions nated water production, transmission and distribution through
of agent, goal and task dependency are used to model and various Power and Water Purchase Agreements with private
examine requirements, architectural and detailed design, as operators, Abu Dhabi Transmission & Dispatch Company, and
well as the implementation of the final system [4]. Abu Dhabi Distribution Company with Al Ain Distribution
In his study, Morandini developed a framework for engi- Company, respectively [16].
neering adaptive systems called Tropos4AS. Its framework Recycled water is managed by Abu Dhabi Sewerage Ser-
provides analysts with modeling features to enhance the re- vices Company (ADSSC) starting from wastewater collection
quirements analysis on the precise knowledge and decision to treatment down to the disposal of bio-solids and excess
criteria that an adaptive system needs to autonomously adjust recycled water. Unfortunately, only 26% of water used by
to dynamic changes. It also contains a planning to software domestics returns to sewer due to poor demand side man-
agents for prototyping and performing requirements simu- agement of the public, such as irresponsible outdoor water
lation. Accordingly, it helps analysts in their requirements usage including but not limited to car washing, irrigation,
validation and refinement phase. Tropos4AS framework is pools filling, etc. Moreover, about 25% of the desalinated
based on three key modeling features aiming simultaneously water is lost from the system due to inefficient transmission
to capture the specific requirements knowledge from, and to and distribution or illegal consumption. However, some efforts
decrease the gap between requirements-time abstractions and a are placed to face such losses and decrease them down to an
run-time representation of requirements for adaptation as well. average of 17.5% by 2030 as announced by the Regulation
These three key modeling aspects are [4]: 1) A goal model that and Supervision Bureau in Abu Dhabi [17].
includes information on the goal types and the associated sat- On the other hand, only 52% of recycled water is used
isfaction conditions. 2) An environment model that represents while the rest 48% is discharged into the sea or in the open
the elements surrounding the system in various conditions, as desert because of insufficient transmission and distribution
well as their effects on the system goals achievements and capacity [18]. Currently, the recycled water is treated up to
satisfactions. 3) A failure model aiming to support engineers the Tertiary level quality and is used in amenity, while in
to specify the unwanted states of affair and to allow them to future it is targeting district cooling, food crops agriculture and
design recovery techniques, to anticipate predictable failures aquifer’s recharge [17]. Although the Environment Agency -
or to recover from the unpredictable ones. Abu Dhabi (EAD) and Abu Dhabi Food Control Authority
(ADFCA) [19] have approved the safe use of Tertiary level
B. System Dynamics recycled water in irrigating eggplant, sweet corn, dates, many
System Dynamics approach was developed by Jay Forrester fruit trees and vegetables which are considered as low risk
at Massachusetts Institute of Technology in 1950 [12], [13]. food agriculture, the public is still not accepting this option due
This methodology is mainly used to characterize, examine and to the lack of awareness and absence of policy enforcement
analyze complex systems with nonlinear dynamics over time tools. However, Regulation and Supervision Bureau (RSB)
using stocks, flows, internal feedback loops, and time delays. It highlighted the need for an enhanced or extra polishing step
is considered a more reliable analysis tool in terms of short and for Tertiary level recycled water before using it in potential
midterm forecasts than other statistical tools. It is distinguished future options [17].
Copyright © 2017 for the individual papers by the papers' authors. Copying permitted for private and academic purposes. This volume is published and copyrighted by its editors.
Currently, the Enhanced level (beyond Tertiary) treatment are of sufficient capacity [23]. However, capacity of
is considered only in a pilot project at Al Nahda farms for the transmitted recycled water amount will vary as part
purpose of irrigation relieving the use of groundwater [20]. of strategies discussed in this paper.
While the fourth level treatment technology is one of the • Potential demand areas to be covered in this study
future options, as announced by EAD and ADFCA [9, 29]. are as per Table I.
This technology will be able to treat industrial wastewater for • The recycled water generated from the tertiary treat-
the same sector usage [21]. Accordingly, with the adoption ment plant will be ultimately used for Amenity as
of such advanced technologies and plants capacity expansion a first priority then Forestry sectors.
efforts that are taking place in the emirate, recycled water will • Recycled water supply to Agricultural sector to be
be enhanced which will help in: first decreasing the pressure on of enhanced quality.
desalinated water and groundwater usage in the areas where
high water quality is not required, second reducing energy
consumption, third cutting down CO2 emissions and finally
saving money. 2) Tropos4As goal modeling: In this section, we will
develop the Tropos4AS goal model for the recycled
III. R ESEARCH M ETHOD water supply system of Abu Dhabi Emirate showing
In this section, an overview of the analytical assessment the extended parts of Tropos goal models in terms of
approach followed in this study is explained. The investigation adoption to environmental changes and identification of
of the characteristics of any system qualitatively is considered possible failures, by understanding the problem, iden-
fundamental. It allows for understanding of the complexity of tifying actors and their goals in terms of strategies
the system and its behavior. Thus, we first investigate the status related to recycled water enhancement (e.g., technolo-
of the recycled water supply system in the Emirate of Abu gies, infrastructure, demand side management, etc.), and
Dhabi to understand its state and dynamic behavior, along with detecting the interactions between the model elements.
the demand side. The objective of this step is to get an insight The next step is describing the system’s functional
about the system actors who have an influence on system and non-functional requirements within its operational
complexity due to requirements and goals prioritization. More environment in the form of one actor related to other
specifically, we model the recycled water current status and actors through number of dependencies. Finally, detailed
strategies placed (or aimed to be in place) towards achieving goal model is specified.
the government goal of maximizing the recycled water usage 3) System Dynamics modeling: A System Dynamics model
and enhancing the system accordingly [14]. is built in Vensim PLE application simulating Tro-
By focusing on Abu Dhabi Emirate case study, we aim to pos4AS models in order to asses defined goals and
evaluate the capability of Tropos4AS approach in characteriz- prioritize them. The System Dynamics model is val-
ing complex systems. With the assistance of System Dynamics idated through built-in error-informing variables and
approach, we aim to evaluate the goal models developed by units checking, as well as conformance to the literature
Tropos4AS. Such step will enable assessing and updating and logical expectations. System Dynamics approach
developed goal models if change in requirements are needed is based on mathematical modeling technique that can
towards making the system more rigorous, through testing represent and analyze complex systems. It enables us
their potential empirically in System Dynamics. The research to understand the dynamic behavior of the recycled
method followed in this study is as follows: water system and monitor the goal satisfaction towards
improving the decision making in our system at run-
1) Data collection: the data used in this study is collected
time. The approach begins with defining the problem,
from literature, including governmental reports, brain-
parameters and goals, and proceeds through the mapping
storming, observation, and discussion with an expert
and modeling stages. We can then study and analyze
from the field of water resources management (EAD).
how the system should behave and the corresponding
Few assumptions are made:
run-time satisfaction criteria. However, we will rely on
• Public Acceptance Rate is considered to be 42.8%
1
Tropos4AS RE approach in early stages modeling of
[22], and assumed fixed throughout the analysis, System Dynamics model. Furthermore, System Dynamic
where it only affects the demand for enhanced will allow us highlighting the key parameters in the
recycled water in agriculture. context of our system that affect goal satisfaction, and
• Wastewater treatment plants capacity is implicitly
modifying different parameters or exogenous variables.
considered while modeling, and assumed capable to These simulations clarify how our system behaves when
receive and treat all RTS amount since some of the an expected or an unexpected change happens in its
current treatment plants are overly used while rest environment at the run-time phase. In our recycled
1 A survey conducted in 2009 to test people awareness on the water scarcity
water system case, the parameters affecting conditions
issue in Abu Dhabi Emirate, and it was found that only 42.8% of respondents of our environmental model are mainly the RTS, the
are aware of the issue importance. transmission capacity and the public awareness.
TABLE I: Assumptions of Demand for Recycled Water
Sector Status Assumption
Demand for Tertiary level
Continue the supply of recycled water
recycled water
and substitute the use of desalinated
Amenity = 90.1 MIGD
water by available Tertiary level
Demand for desalinated water
recycled water.
= 133.63 MIGD
Demand for groundwater Substitute the use of groundwater by
Forestry
= 209.8 MIGD available Tertiary level recycled water.
Substitute 30% of current demand for
Demand for groundwater
Agriculture groundwater (310.1 MIGD) by available
= 1033.5 MIGD
Enhanced level recycled water.
potential errors that lead to the failure of our system, and the
possibility and plans to monitor these errors to get back our
system to the right track towards achieving the main goal. As
aforementioned, the Tropos4AS modeling methodology con-
cepts are extracted from i* methodology, and its development
procedure is based on the agent-oriented software engineering
methodology Tropos which focuses mainly on the actors rep-
resenting the system-to-be. Consequently, Tropos4AS allows
modeling requirements taking into consideration the behavior
of the system to satisfy all its goals. The model includes three
main components:
• An extended goal model with the corresponding run-time
satisfaction conditions.
• An environment model indicating the critical key ele-
ments in the operational phase of our system that affect
Fig. 1: Sensitivity analysis the goal satisfaction.
• A failure model pointing out any potential errors that may
lead to the failure of our system consequently preventing
4) Results Evaluation2 : A sensitivity analysis is performed the system from achieving its goals and the inclusion of
on the following built-in strategies in the form of ex- the necessary recovery plans.
ogenous parameters which are: RTS Rate Parameter, Extended Goal Model: Tropos4AS methodology includes
Tertiary Level Recycled Water Transmission Capacity information about the dynamics of goal satisfaction in goal
Parameter as well as a fixed Public Acceptance Rate, models, which is a characteristic of this approach to allow
resulting into four scenarios as per Figure 1. monitoring the goal satisfaction as well as the decision-
IV. R ESULTS making in an adaptive system at run-time. The extended model
includes the main goals as well as the sub-goals in addition to
The Tropos4AS modeling methodology has been defined
the plans required and necessary to apply for the satisfaction
considering the key properties that need to be engineered into
of these goals. Figure 2 shows the extended goal model of our
an adaptive system. This methodology helps the system to
case study.
adapt autonomously, by using a combination of current capa-
In order to fulfill the main goal, which is to enhance the
bilities and conditions at run-time. The assumed stakeholder in
recycled water system in Abu Dhabi Emirate, we need to en-
our case is Abu Dhabi Government and the actor is ADSSC,
sure the satisfaction of the two major components in the model
they are both the decision makers of our project. Once the
which are the increase of the recycled water usage and the
stakeholders and actors have been assigned, the second step is
enhancement of the system efficiency. The sub-goals related
to define the goals. Our main goal is to enhance the recycled
to the satisfaction of these goals are included in the model.
water system in Abu Dhabi Emirate. This can be achieved by
First, increasing the collection, by improving the collection of
ensuring the satisfaction of two goals: increasing the recycled
the recycled water we can increase the recycled water usage
water usage from one side and improving the efficiency of the
and consequently achieve our main goal. The plan necessary
system from the other side.
for the satisfaction of this goal is to enhance the return to sewer
It is essential to include in our system the main goals to
rate as well as the improvement of the transmission system.
reach as well as the sub-goals, to specify what effects the
Second, increasing the transmission capacity, where this sub-
environment has on the system at run-time in addition to the
goal is one of the essential ones to increase the recycled water
2 Variable names between brackets are as used in System Dynamics Model usage as well. The necessary plans are to develop projects to
in Vensim PLE improve the plants’ capacities and to enhance efficiency of the
transmission in the system. Third, the public acceptance which Failure Model: Another important feature of the Tropos4AS
is another important aspect affecting the usage of the recycled modeling methodology is that it introduces a failure model. Its
water. To achieve that goal, we need to treat the recycled water main objective is to provide means for capturing exceptional
to the enhanced level, after the tertiary one, by using advanced circumstances and probable undesirable activities at the run-
technologies. Using such an advanced treatment should lead time stage. These activities are reflected in the model as
to the population having more trust in the purity and safety of errors leading to failures of the system. They are mainly
this water. a result of any uncompleted requirement, or a consequence
Finally, it is necessary to develop more enhanced technolo- of circumstances that were not taken into consideration at
gies used for the recycled water process. By doing so, we the requirements analysis stage or the design-time stage. The
are ensuring the satisfaction of both main goals, increasing failure model helps anticipate any error of failure at the run-
the recycled water usage and the improvement of the system time phase by adding the recovery activities known as plans.
efficiency. The essential plans needed are first to enhance the Through the following Figure 4, we explain the failure
wastewater treatment process and then the privatization of the model of our case study that includes potential errors and the
recycled water related project that is considered as a long-term failures resulting from these errors, and the necessary recovery
plan. activities or required plans. First, cutting the transmission and
Environment Model: Adaptivity’s main concept is how the a plant shutdown are both potential errors that can happen to
behavior of a system is modified whenever any kind of changes our system at run-time and lead to a failure in the operation,
happen in its environment in order to keep its functionality as thus leading to a disruption in the supply of the recycled water
required. The environment model points out the dependencies affecting directly the recycled water usage which will decrease
among the agents and stakeholder goals and its intentional and subsequently. In order to deal with this failure, many recovery
non-intentional environment at the run-time stage. Tropos4AS activities could be taken, such as transmitting recycled water
methodology adds the concept of conditions and context in via tankers. This action can be considered as a short-term plan
order to outline the run-time goal satisfaction procedure in action guaranteed immediately. Another short-term plan is to
response to any environmental changes. In this regard, precise follow the safe disposal strategies of wastewater into the sea or
conditions are connected to goals, showing the constraint or desert. Additional recovery activity is the maintenance of the
the context necessary in the environment for the achievement damages and the repair of the disruption, both of which may
of this specific goal at run-time. be considered either long-term or short-term depending on the
In our case study, and as represented in Figure 3, the first size of the damages and the time needed for the restoration.
condition is related to the collection control. We need to Another set of errors presented in our model is whenever
maintain a collection of not less than a 26% of the wastewater, a leakage in the transmission happens or if the plants are
which is the current amount in Abu Dhabi Emirate. Failing to overloaded, these errors cause a drop in the efficiency in our
do so will affect the amount of resulting recycled water pro- system and highly affect our main goal to enhance the recycled
duced, reducing the amount of recycled water used, affecting water system in Abu Dhabi Emirate. As restoration plans,
therefore the goal to increase the recycled water usage. The we first propose to control the leakages and to provide the
second condition to apply is associated to the usage control. necessary maintenance and reparation. Furthermore, recovery
The amount of the treated wastewater discharged into the sea activities are to propose projects to enhance the transmission
should not exceed 48%, the current amount in Abu Dhabi. infrastructure and to increase the recycled water treatment
In case this volume is surpassed, the usage control will be plants capacity.
affected and accordingly the efficiency of our system will Linking between the extended goal model, environmental
decrease affecting directly the main goal and preventing the model as well as failure model built using Tropos4AS gener-
enhancement of the recycled water system. The third condition ates a comprehensive full model for the recycled water system
to apply is to sustain the current transmission capacity, and not in Abu Dhabi.
going below 52%, which is the current amount transmitted While this is the work in progress, and we are currently
in Abu Dhabi Emirate. Going below this limit may have integrating the results of Tropos4AS with the System Dy-
negative consequences on both the recycled water usage and namics model, we have already produced some results that
the efficiency of our system thus preventing the satisfaction show the gaps in recycled water supply resulting from running
of our main goal to enhance the recycled water system in the System Dynamics model over the agreed scenarios, as
Abu Dhabi Emirate. Finally, it is important to include the presented in Figure 5. So far, the scenario 2 seems to be
public awareness and acceptability of the recycled water. the best having the minimum shortfall amount, indicating that
Approximately 42% of Abu Dhabi inhabitants are assumed the RTS rise has a great impact on reducing the supply gap.
aware of the importance of the recycled water, consequently Maximizing both strategies results in the second minimum
they accept and encourage the usage. Agitating the treated supply gap where the system could satisfy almost 33% of its
wastewater system negatively affects the trust of people in the demand for Tertiary recycled water and 43% of its demand for
system and in the purity of the recycled water, thus decreasing Enhanced recycled water. The BAU scenario is found better
its usage and preventing the satisfaction of the main goal in than further enhancing Tertiary recycled water transmission
our model. capacity, thus saving cost.
Fig. 2: Extended Goal Model
V. D ISCUSSION and substituting the use of depleting groundwater resources.
In this paper, we have shown the preliminary results of Public awareness is indeed important for system enhancement
system modeling using Tropos4AS and System Dynamics although no effect has been noticed in our analysis so far. We
through a case study of Abu Dhabi Emirate recycled water believe this is due to a lower amount of supply available than
system. We are currently simulating the goal models and impacted demand.
short-term plans defined in Tropos4AS using Vensim PLE,
B. Research Contribution
and running four different scenarios including BAU. The full
results of this study will be based on the identified system By investigating the literature, we could not find any ap-
boundary, modeling setup and assumptions. plication on water systems in general and in recycled water
system in particular using either goal-based or agent-based
A. Outcomes modeling methods. This is most likely due to the engineering
In the previous sections, we have presented the applicability discipline distance. In our study, we applied Tropos4AS pro-
of Tropos4AS at the recycled water system in Abu Dhabi cedure to the recycled water system in Abu Dhabi Emirate,
Emirate. Linking between System Dynamics and Tropos4AS using real data and hopefully providing tangible results by the
seems promising so far. The System Dynamics method is time the study is fully completed. Furthermore, this study con-
helping us evaluate the goals built in Tropos4AS, where max- tributes to the knowledge of stakeholders impact on recycled
imizing the wastewater collection has more impact on system water system, and highlights the potential and possible risk
improvement than maximizing transmission capacity under the of the current plans or decisions, thus accordingly helping in
given modeling setup. Thus, so far it seems that investing in improving the system towards making it more resilient and
maximizing the return to sewer amounts has a higher potential vulnerable.
and could further enhance the recycled water system in Abu Combining Tropos4AS and System Dynamics methods have
Dhabi Emirate. Adopting enhanced treatment technologies to a potential to be a valuable addition to the RE research.
treat the amount that used to be discharged has a potential Linking between both approaches and using the resulted
too in covering a good portion of the agricultural demand, unified validated model will support robust scenarios testing,
Fig. 3: Environment Model
thus investigating the power of potential strategies in future as VI. C ONCLUSION AND F UTURE W ORK
well as improving the decision making. This study is the first
of its kind since RE helps defining requirements for System This paper has reported the positive preliminary results in
Dynamics models but the opposite relation has never been our work on integrating Tropos4AS and System Dynamics
investigated. So far, we can see both methods complementing method in order to produce comprehensive goal models that
each other effectively. can be quantified, simulated, and used in decision making in
water security domain. Given our current progress, we should
be able to present full results during the workshop.
C. Limitations
Besides the potential of enlarging the scope of this study
An important limitation we faced in our study is meeting the and making it more detailed, the boundary could also be
stakeholders and actors, which are in our case representatives improved by integrating the other water resources in Abu
from Abu Dhabi Government and ADSSC, to perform a deeper Dhabi Emirate and use the resulting model as an integrated
investigation of the interaction between system actors and water resources management tool. Other potential strategies
goals. This restriction is preventing us from having their com- that could be further analyzed are: water treatment plants
ments, plans, and other feedback on different conditions, errors capacity improvement, controlling leakage from water system,
and failures that our system may face at run-time. Having data analyzing the effect of water price on return to sewer rate, etc.
about system design and operation could have better impact on Furthermore, the future work should also monitor and analyze
system improvement if available. Furthermore, the study has the correctness of the model during the system operation. This
not so far considered seasonality in demand and production should be done through the implementation and collection of
capacity planning due to the limited scope in addition to the data from the implemented system and comparison with the
time constraint. model. Evaluating the results could be better visualized using
Fig. 4: Failure Model
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