The barge Arthur J sank in Lake Huron, capesizing the tugboat Madison. the both vessels were operating on 5 nautical miles off the entrance to the St Clair River. Both vessel has total about 7.0 tons of fuel and a small volume of luboil, so the local authorities made special construction to restrict the spillage and the water pollution. The both ships are operated and owned by the US company MCM Marine Inc and the reason for the accident is still unknown. According to the Coast Guard, the ships sank due to engineering problem in the dredge barge. The vessel’s hull broke and while sinking capesized the towing tug Madison. The accident happened close to the shore and there were no serious injured people, but the water pollution might cause serious problem to the Lake Huron eco-system.