Skip Navigation


Security Levels

USCG Vessel Traffic Service Banner image

Guide to Marine Communications on San Francisco Bay

Listen to Channel 14 prior to departure and while transiting the bay. This will provide invaluable information on vessel movements.

The following terms will improve your understanding of Channel 14. CG racing stripe horizontal rule


Pilot on board:
Indicates large vessel.
Pilot unit designators:
Individual call signs for harbor pilots of vessels in the port. They can be numbers or letters "Unit 77" or "Unit A".
Channel 16:
International hailing and distress frequency. [Vessels checked in with VTS are not required to monitor Channel 16.]
Channel 14:
Dedicated vessel traffic service frequency. [Please Monitor!]
Channel 13:
Dedicated for vessel-to-vessel communications to discuss vessel movement.
In/Out of the Channel:
Within or outside the boundaries of a channel or shipping lane.
To pass another vessel transiting in the same direction.
Port to port passing:
When two vessels pass in opposite directions with the port side of each vessel towards the other vessel. Sometimes referred to as: "One whistle".
Starboard to starboard passing:
When two vessels pass in opposite directions with the starboard side of each vessel towards the other vessel. Sometimes referred to as: "Two whistles".
Operation where mud and sand are removed from the bottom of a waterway. Restricts the dredge’s ability to maneuver.
Slow bell:
Operating a large vessel at a slow speed, but fast enough to maintain steerageway.
No wake:
Operating at a speed slow enough to minimize the waves created by a vessel moving through the water.


Refer to NOAA chart #18649
San Francisco docks are called piers.
Oakland docks are called berths.
Golden Gate Bridge:
Spans the entrance to San Francisco Bay.
North Tower:
The northern supporting tower.
South Tower:
The southern supporting tower.
Vessels entering San Francisco Bay from sea.
Vessels departing San Francisco Bay to sea.


Central Bay lane intentions:
Defines which traffic lane a vessel intends to transit.
Westbound traffic lane:
North of Alcatraz and south of Harding Rock. One way lane.
Eastbound traffic lane:
South of Alcatraz. One-way lane.
Deepwater traffic lane:
Two-way lane north of Harding Rock.
Harding Rock:
An underwater obstruction marked by a buoy (HR) northwest of Alcatraz.
Blossom Rock:
An underwater obstruction marked by a buoy (BR) southeast of Alcatraz.
Point Blunt:
Point of land on the southeast corner of Angel Island. [Major large vessel turning point.]
Alcatraz Dumpsite:
Disposal area for dredged material south of Alcatraz.


Bay Bridge:
Spans the central bay between San Francisco and Oakland.
Bridge Span Intentions:
Each support of the bridge is identified with a letter. Vessel transit intentions are based on tide, current and other traffic in the area. Transit intentions are communicated by vessels as follows:
(A-B) Alpha-Bravo Span:
Wide span west of YBI, closest to San Francisco.
(B-C) Bravo-Charlie Span
Narrow span west of YBI, just west of the center support.
(C-D) Charlie-Delta Span
Narrow span west of YBI, just east of the center support.
(D-E) Delta-Echo Span
Wide span immediately west of YBI.
(G-H) Golf-Hotel Span:
Wide span immediately east of YBI.


Oakland Bar Channel:
The marked channel south of Yerba Buena Island, leading to all Oakland Berths.
Oakland Outer Harbor:
The harbor area closest to the Bay Bridge.
Oakland Inner Harbor:
The harbor area in the Oakland Alameda Estuary.
Oakland Middle Harbor:
The harbor area between the outer and inner harbors.
The waterway between Oakland and Alameda.
"9th Avenue" Turning Basin:
Area in the Oakland Estuary near 9th Avenue Terminal where large vessels can turn around.
Schnitzer Turning Basin:
Area in Oakland Estuary near Schnitzer Steel where large vessels can turn around.


Anchorage 8/9:
The commercial vessel anchorages south of the Bay Bridge.
Anchorage 5:
South of Red Rock, between the main shipping channel and Southampton Shoal Channel.
Anchorage 7:
Along the west side of Treasure Island.
chart showing the central San Francisco Bay
Inland Rule 9 applies in all Regulated Navigation Areas


Richmond / San Rafael Bridge:
Spans the north bay between Richmond and San Rafael.
East Span:
Channel passing under the bridge east of Red Rock.
West Span:
Channel passing under the bridge west of Red Rock.
Southampton Shoal Channel:
Dredged channel providing deep draft vessels access to the Richmond Long Wharf and Richmond Inner Harbor.
Richmond Long Wharf:
The long pier south of the Richmond /San Rafael Bridge.
Richmond Harbor Channel:
Narrow channel south of Richmond Long Wharf connecting to the Richmond Inner Harbor.


Towing "on the hip":
Towing with the tug tied to the side of the barge.
Towing astern:
Towing a barge or vessel some distance behind the tug. Sometimes referred to as: "on the wire."
Towing ahead:
Having the tug push the barge ahead of it. Sometimes referred to as: " on the push" or "in the notch."
Adjusting tow:
Anchoring, breaking tow, or adjusting length of tow.
Last Modified 1/12/2016