European cities face considerable challenges to achieve a sustainable management of their urban water system. Digital technologies offer a variety of opportunities and solutions to tackle these challenges. Digital-water.city works towards three main objectives for sustainable waste and sewage management: 1. Health protection 2. Performance and return on investment 3. Public involvement. To do so, digital-water.city is active in five European cities with 15 innovative digital solutions. These state of the art digital solutions range from augmented reality to real-time monitoring and artificial intelligence and were developed in collaboration with diverse stakeholders. Digital-water.city has received funding from the European Union's H2020 Research and Innovation Programme under Grant Agreement No. 820954.