## 1 Introduction  
Modern infrastructures--including urban water grids--face sustainability and resiliency challenges. Changes in climate and population are making water supplies scarcer in some areas [1; 2; 3]. Water systems often waste substantial quantities of treated water in both the distribution system and at the end-use location, mainly through leaks [4; 5]. In many places, such as the Southwest U.S., water must be conveyed over long distances to water treatment plants, resulting in the use of significant amounts of energy for pumping [6]. Maintaining water quality also remains a challenge in the distribution system, where contaminant intrusion and biofilms reduce water quality [7; 8]. Problems with end-user plumbing can then further decrease water quality. The water distribution system is also vulnerable to targeted attacks through water poisoning, as well as catastrophic water main breaks due to undetected pipe deterioration [3; 9]. Technological revolutions such as electricity and the combustion engine transform economies and societies, including supporting infrastructures supplying water, energy, and mobility. Information and communications technology (ICT) has been the dominant technological revolution for several decades. In addition to economic and social effects, ICT also drives changes in environmental issues and add to the portfolio of potential solutions [10]. The benefits of ICTs can presumably be enhanced through intentional adoption for sustainability and resiliency. Compared to manufacturing and service sectors, adoption of ICT in infrastructure is relatively slow. One factor is presumably longer replacement time scales. The last decade has seen progress in the development of the smart electrical grid [11]. Smart electric meters and other two-way communication devices have been installed in homes and businesses to allow electric utilities to track electrical usage in real-time. This allows utilities to make continual adjustments to the system. Whether responding to a power transformer failure or trying to help shift electrical usage to off-peak time, the hope is that smart electrical grid will make power generation and delivery more efficient and resilient and less costly, while reducing total energy use [12]. Using ICTs in water systems could lead to smart water grids that are analogous to smart electrical grids. A smart water grid would integrate sensors, controls, and analytical components to ensure that water is efficiently delivered only when and where it is needed and help to ensure the quality of that water. Considering smart water grids as integrated systems is just beginning to be considered by researchers and utilities. In the literature, there are efforts to develop and analyze the components of smart water grids. Some of the literature focuses on the benefits of specific technologies such as smart pumps [13]. Other research takes a step further and analyzes the implementation of specific smart technology systems, such as automated meter reading (AMR) and advanced metering infrastructure (AMI) for water infrastructure, which are two different systems for using smart water meters for residential and commercial water consumption billing [14; 15]. However, integrative, strategic, and macro-level discussions of smart water grids are lacking in academic and other literatures. This paper begins to fill this gap by presenting a vision of how smart technologies could be implemented at several scales and combined to contribute to more sustainable and resilient water systems. Additionally, this paper seeks to outline the challenges to the realization of smart water grids. It is interesting to note that the smart phone is a marvel of modern information technology that is owned by hundreds of millions of consumers around the world. In contrast, much of the technology forwater distribution and use is similar to that of fifty, or even a hundred years ago. Outside of the water treatment plant, there is little use of information technology in water systems.