Back River encompasses all the waters of Back River and its tributaries westerly of a line beginning at a point at or near Lat. 39° 14.95' N., Long. 76° 24.05' W., then running 173° (True) to a point at or near Lat. 39° 14.30' N., Long. 76° 23.95' W.
Md. Code Regs. 08.18.05.01