Sea markers crossword clue. The-Chronicle newspaper on May 6, 2017.
The answer is: BUOYS
Buoys and markers are invaluable guides to safe navigation. The system of buoys used in Canada is outlined below. Complete details of the system are available from all Coast Guard offices, chart distributors, or CHS chart distributors.
Upstream direction: is the direction taken by a vessel when proceeding from seaward, toward the headwaters of a river, into a harbour or with the flood tide