Clay Township is a civil township of St. Clair County in the U.S. state of Michigan. As of the 2010 Census, the township population was 9,066. The township includes Harsens Island, which is inhabited. Clay Township Park is located on Pte Tremble Road, next to the Clay Township offices and Police Department. It includes a children’s playground and a water splash pad. Impromptu volleyball games take place, and residents enjoy the walking paths. The park features a basketball court that is flooded in winter to serve as an ice skating rink and walking trail. It is lighted to facilitate evening accessibility. A concession building and restroom facilities are also available.
According to the United States Census Bureau, the township has a total area of 82.5 square miles (214 km2), of which 35.5 square miles (92 km2) is land and 47.1 square miles (122 km2) (57.03%) is water. The 37-square-mile (96 km2) township includes Harsens Island, Russell Island, Dickinson Island and St. Johns Marsh.As of the census of 2000, there were 9,822 people, 3,934 households, and 2,844 families residing in the township. The population density was 277.0 per square mile (106.9/km2). There were 5,325 housing units at an average density of 150.2 per square mile (58.0/km2). The racial makeup of the township was 97.92% White, 0.20% African American, 0.68% Native American, 0.11% Asian, 0.21% from other races, and 0.87% from two or more races.
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