That was a federal government decision when it devolved the various ports and harbours. There were an original 17—now 18—that were considered of strategic significance and were devolved into port authorities, which are shared governance organizations related to the federal government. The federal government at the time made the decision to allow the Port of Churchill to go private.
Evidence of meeting #7 for Finance in the 42nd Parliament, 1st Session. (The original version is on Parliament’s site, as are the minutes.) The winning word was infrastructure.
A video is available from Parliament.