The Milwaukee Metropolitan Sewerage District is a state-chartered, government agency providing wastewater services for 28 municipalities. The District's 420-square-mile service area includes all cities and villages, (except the City of South Milwaukee), within Milwaukee County and all or part of 10 municipalities in the surrounding counties of Ozaukee, Washington, Waukesha and Racine. Wastewater is conveyed to the Jones Island and South Shore wastewater treatment plants by a 2,200-mile system of collector sewers and a 310-mile system of intercepting and main sewers. The two treatment facilities collect and treat more than 200 million gallons of wastewater each day, returning clean, clear water to Lake Michigan. In addition to providing wastewater services, MMSD, in conjunction with area stakeholder groups, plans and oversees projects to reduce the risk of flooding in six Milwaukee-area watercourses in order to protect its sewer infrastructure. Other MMSD functions include water quality research and laboratory services, operating household hazardous waste and mercury collection programs, and involvement in various environmental partnerships.