Port Huron Charter Township is a charter township of St. Clair County in the U.S. state of Michigan. The population was 10,792 at the 2020 Census. The city of Port Huron is adjacent to the township. According to the United States Census Bureau, the township has a total area of 13.1 square miles, of which 12.9 square miles is land and 0.2 square mileā¦Port Huron Charter Township is a charter township of St. Clair County in the U.S. state of Michigan. The population was 10,792 at the 2020 Census. The city of Port Huron is adjacent to the township. According to the United States Census Bureau, the township has a total area of 13.1 square miles, of which 12.9 square miles is land and 0.2 square miles is water.