Smart Energy and Water Efficiency Act of 2019 This bill requires the Department of Energy (DOE) to establish and carry out a smart energy and water efficiency management pilot program. Under the program, DOE must award grants to water authorities (i.e., authorities that provide water, wastewater, or water reuse services) for demonstrating advanced and innovative technology-based solutions that will increase and improve the energy efficiency of water, wastewater, and water reuse systems; support the implementation of innovative processes and the installation of advanced automated systems that provide real-time data on energy and water; and improve energy and water conservation, water quality, and predictive maintenance of energy and water systems, through the use of Internet-connected technologies.