CHICAGO — St. Lawrence Seaway Management Corp. will begin closing the seaway to navigation in stages for the winter season.

All vessels must be clear of the Montreal-Lake Ontario section of the seaway by Dec. 29; the Welland Canal, which connects Lake Erie and Lake Ontario, by Dec. 30; and the Sault Ste. Marie Locks and Canal by Jan. 15.

A number of ports east of the seaway’s St. Lambert Lock, its most easterly lock, will remain open to navigation during winter.

Northbound ships not otherwise restricted will be accepted for transit through the Montreal-Lake Ontario section at Cap St. Michel through Dec. 24. Southbound ships not otherwise restricted will be accepted for transit through this same section at Cape Vincent, also through Dec. 24.

After the closures, ships traveling under special agreements will be restricted by size and draft due to expected ice conditions.