A federal plan to close Thunder Bay's Coast Guard radio station and monitor Lake Superior waters out of Sarnia is raising concerns among mariners and volunteer rescuers.

The Thunder Bay Coast Guard marine communications and traffic centre, which keeps a listening watch over the Canadian waters of Lake Superior, is one of 10 centres across the country slated to be closed in what Fisheries and Oceans Canada says is a move to adopt new technology. The cuts will reduce the number of stations nationwide from 22 down to 12 and the union representing radio operators in Thunder Bay says staffing is not expected to increase in Sarnia to handle the extra load.