- Clay Township became a Township in 1828.
- Elections for the board are held in presidential election years.
- The 37 square mile township includes Harsen's Island, Russell Island, Dickinson Island and St. Johns Marsh.
- Ferry Service connects Harsen's Island with the Mainland.
- Clay Township is a center of water recreation and a public pier is located off M-29 at Pearl Beach.
- The Colony Tower, at the southwest corner of Clay Township, has been a registered landmark since the 1920's.
- At one point, the 136 foot Colony Tower housed a 60,000 gallon water tank. It provided water to the Colony's residents.
- Harsen's Island and the St. Clair Flats combine to create one of the largest inland fresh water deltas in the world.
- The Michigan Department of Natural Resources maintains two access sites on Harsen's Island, One on the South Channel and one on the Middle Channel.
- St. John's Marsh is also managed by the DNR and sports an access site and areas for fishing.
- As of 2000 Clay Township had a population of 9,822 at the time being the second highest populated Township in St. Clair County.