We Are One Water The Great Lakes Water Authority (GLWA) provides nearly 40 percent of Michigan’s population with water of unquestionable quality, as well as effective and efficient wastewater services to nearly 30 percent of the state. GLWA is all about the movement of water from the environment, to our customers, and back to the environment. We ensure our member partner communities get the highest quality water using treatment standards that are stricter than state or federal regulatory requirements. And once the water has been used, we run it through our treatment process again before returning it to the environment – often cleaner than when we received it. Working hand-in-hand with our member partners, we provide water and wastewater services of the highest quality. Together, we are one water.