## 1 Introduction  
The concept of a smart water grid refers to augmenting existing water distribution grids by introducing continuous, on-demand and bidirectional data exchange between metering devices, water flow equipment, utilities and end-users [1]. Smart water grids that integrate Information and Communication Technologies (ICT) in water systems can bring benefits analogous to those of smart electrical grids and improve management in risk-minimization for water infrastructure [2; 3]. Smart metering deployments are considered of paramount importance towards the realization of smart cities as they provide multiple benefits to water utilities and end-users. Compared to traditional, manual, metering devices, smart water meters (a) provide accurate data collection also during low water flows, (b) measure backflow, which can indicate a problem in the system, and (c) are less susceptible to corrosion from particles in the system [4]. The data collected from the resulting infrastructure enables the analysis of water demand, which helps better comprehend water end-use and in this way influence the design of urban water supply networks [5]. The availability of real-time data at high temporal frequency can help water utilities identify leaks and fixture malfunctions, timely schedule maintenance or upgrades of the infrastructure, and ultimately help them meet goals for sustainable water use [6]. Such knowledge extracted from the data can also be used in conjunction with water consumption demand models to identify the factors contributing to peak demand [7]. Moreover, advanced optimization techniques can be employed to generate water savings throughout the urban water life cycle process resulting in operational efficiencies for the owner of the water distribution network [8]. Moving beyond the use of data, recent developments in smart networked actuators help create autonomous smart grids, where metering and actuation devices cooperate to manage the distribution network more efficiently than any manned service could ever do [9]. A detailed review of existing smart water grids and the functionalities provided for water utilities was presented in [10]. The deployment of smart water grids offers many benefits also to the end-users, that is, the clients of water utilities [3]. The real-time data collected on water quality and the consumption along with the respective knowledge extracted are used to develop environmental awareness and organize campaigns regarding the use of scarce resources such as freshwater, targeting mainly young people and their everyday habits [11]. Schools are the centre of such acts, using the data provided by real-world smart grids and Internet of Things (IoT) devices. The outcomes of these acts are studied with regards to the behavioural changes achieved in the direction of promoting sustainability on various ongoing research projects [12]. Easy to implement, water quality monitoring solutions allow us to develop education-related applications and scenarios that help achieve such goals [13]. Mainly IoT technologies initiatives can benefit from immediate, direct, feedback regarding the actions performed and the solutions applied [14]. The design and development of open and expandable end-to-end information-based grid management systems is a challenge. A vision of how smart technologies can be implemented at several scales and combined to contribute to more sustainable and resilient water systems was presented in [15]. From an ICT perspective, one of the key challenges is the very large volume of data generated by the smart meters and how it is effectively communicated across all elements of the systems [16]. The multi-modal contexts of city-scale applications and the need for data access between different organizations introduce further technical challenges on transferring massive datasets collected across disparate infrastructures [17; 18].