Wynne, YOUR Real Estate Consultant for LIFE!!!The 37 square mile township includes Harsen's Island and St. John's Marsh. Ferry Service connects Harsen's Island with the mainland. Colony Tower at the southwest corner of Clay Township, is a registered historic site and a local landmark since the 1920s. Clay Township is a center of water recreation. A public pier is located off M-29 at Pearl Beach. DemographicsTownship Offices: The township hall is located at 4710 Pte. Tremble Road adjacent to the police department. Hours are 8 a.m. to 5 p.m. weekdays. 794-9303. Fax: 794-1864Library: Algonac/ Clay Township Library is located at 2011 St. Clair River Drive. 794-9015.Museum: Clay/Algonac historical society has restored a log cabin on the municipal grounds. It dates back to the early1800s and ... 03/19/2007