 We can survive without food for several weeks, but without water only for a few days. The planet has plenty of water, but over 99% of it is either salty, wrapped in glaciers or otherwise untrinkable. It is then not surprising that civilizations have mostly flourished around sources of drinkable water. Yet today, one billion people in the world do not have access to clean drinking water. That's one in six people in the world. Six to eight million people die every year from water-related diseases and disasters. I had heard all of these statistics, but until only a few years ago, I was not really aware of the challenge. One day a colleague, Professor Ong, asked me whether some of the robots that I developed for marine applications such as surveying and ocean exploration could be used for freshwater monitoring in reservoirs and waterways around Singapore. I knew very little about water quality monitoring at that point in time, but I figured we could take some off-the-shelf sensors, put them on the robots and have them swim around. However, having worked with these robots for many years, I also knew they tend to be complex, expensive, and logistically challenging to deploy and to operate. What we needed was a simpler solution. Couldn't we just take fixed sensors and put them around reservoirs? Wouldn't that be simpler? The next few days I spent doing a little research. What I found was it was indeed common for people to put fixed sensors around reservoirs, but it was woefully inadequate because water quality tends to change dynamically with space and time. People often augment fixed sensors with manual water quality sampling, but this tends to be manpower intensive and therefore quite limited. Having many robots swim around a lake or reservoir would indeed be a nice solution, but for that we needed many relatively simple robots which were less expensive and could swim around with minimal supervision. The main reason why underwater robots are complex and expensive is that they are unable to use certain technologies, such as GPS or cellular technologies for communication or Wi-Fi because these technologies rely on radio waves that are rapidly absorbed by the water. If we could take our robots and adapt them such that we put water quality sensors under the robot and have the robots swim mostly at the water surface, then we could make them simpler. The robots then would be able to access GPS for navigation and cellular networks for communication. Over the next few months, some of my students and engineers helped me do exactly this. We refactored technology that we had developed for ocean-going underwater robots into freshwater monitoring surface robots. The NUS Water Assessment Network, or NUS1 for short, was born. NUS1s now swim around lakes and reservoirs in Singapore, providing real-time access to data about water quality. They blend in the natural surroundings and they coexist with other users of the water bodies. Experts can access data that is generated by NUS1s over the cloud using a web interface. If experts determine that a particular event requires deeper investigation, they can ask the NUS1s to go to particular locations and investigate the event. This is extremely useful in order to be able to detect potential problems such as contaminant seepage or harmful algae blooms at a very early stage. NUS1s are instrumented with common water quality parameters, probes such as pH, temperature, dissolved oxygen, turbidity and various types of chlorophyll. However, they are also designed with the flexibility to be able to add other sensors as necessary. While in-situ sensing and real-time monitoring is invaluable for water quality management, it is not a substitute for control laboratory testing. If experts determine that a particular event requires deeper investigation, they can ask the NUS1s to bring back a water sample to shore for controlled lab analysis. NUS1s provide us the ability to monitor water quality and to detect potential water-related problems before they become real problems. Singapore has been a fantastic test bed for this technology and now we hope to replicate this technology in other parts of the world with an aim to try and provide clean drinking water for everybody. Thank you.