(a) The anchorage grounds—(1) Anchorage A (general). Beginning at latitude 43°39′37″ N, longitude 070°14′35″ W; thence approximately 090° for 1550 yards to Fort Gorges Island Ledge Buoy 4; thence 350° for 300 yards; thence 025° for 780 yards; thence 303° for 750 yards; thence 254° for 560 yards; thence 186° for 750 yards and thence to the point of beginning.

(2) Anchorage B (general—primarily intended for deep draft vessels). Beginning at Fort Gorges Island Ledge Buoy 4; thence 062° to Little Diamond Island; thence along the southwestern shore to the pier on the southern end of Little Diamond Island; 133° for 1200 yards; 270° to House Island Light; thence along the western shore of House Island to Fort Scammel Point Light; thence 325° for 1700 yards to the point of beginning.

(3) Anchorage C. Bounded on the northwest by House Island; on the north by a line running 90° from House Island Light to Peak Island; on the east by the western shore of Peak Island, by a line running 198° from the westernmost point on Peak Island to Cushing Island, and by the shore of Cushing Island to its westernmost point; and on the southwest by a line running from the westernmost point on Cushing Island to Fort Scammel Point Light.

(b) The regulations. (1) Anchorage B is intended for general purposes, but especially for use by oil tankers and other large deep-draft ships entering harbor at night and intending to proceed to the dock allotted at daylight the following morning or as soon as practicable. This area is also to be used for quarantine anchorage. Vessels must be so anchored in this area as to leave at all times an open usable channel at least 100 feet wide for passage of ferry and other boats between Portland, Peak Island, and Bay Points. Any vessels anchored in this area shall be ready to move on short notice when ordered to do so by the Captain of the Port.

(2) Anchorage C is intended for use only by small vessels and for temporary anchorage.