Effective 11 a.m. Thursday, February 2, the water between St. Ignace and Mackinac Island will be closed, according to the United States Coast Guard. Ferries have been shut down for the season, and anyone on boats in the waterway could be fined.

According to federal law, certain channels, including the ones between St. Ignace and Mackinac Island and between Bois Blanc Island and Cheboygan and a few others in the area, must be protected to allow for an ice bridge to form during winter months, said Mark Gill, director of Vessel Traffic Services for the U.S. Coast Guard in St. Ignace. The Coast Guard usually closes the St. Ignace to Mackinac Island channel in mid-January, and the closure is triggered when the ice forms so ferries can’t operate or when ferry companies say they are done operating for the season, Mr. Gill said.

The closure will be lifted in the spring. Mr. Gill said the Coast Guard may receive a request from ferry companies but usually hears requests from Mackinac Island officials to reopen the channel. The Coast Guard will put out notice before sending icebreakers through to reopen the channel, he said.