Waterways Management Branch

Broadcast Notices to Mariners are made by the Coast Guard through Coast Guard and Navy radio stations.  These broadcast notices, which are broadcast on VHF-FM, NAVTEX, and other maritime frequencies, are navigational warnings that contain information of importance to the safety of navigation. Included are reports of deficiencies and changes to aids to navigation, the positions of ice and derelicts, and other important hydrographic information.

Local Notice to Mariners (LNM)

Local Notices to Mariners (U.S. regional coverage) are another means by which the Coast Guard disseminates navigation information for the United States, its territories, and possessions.  A Local Notice to Mariners is issued by each Coast Guard district and is used to report changes and discrepancies to aids to navigation maintained by and under the authority of the Coast Guard.  Local Notices to Mariners contain other marine information such as channel depths, naval operations, regattas, etc., which may affect vessels and waterways within the jurisdiction of each Coast Guard district.  Reports of channel conditions, obstructions, menaces to navigation, danger areas, new chart editions, etc., are also included in the Local Notice to Mariners.  These notices are essential to all navigators for the purposes of keeping their charts, Lights Lists, Coast Pilots and other nautical publications up-to-date.  These notices are published as often as required, but usually weekly.  They may be obtained via the U.S. Coast Guard Navigation Center website at http://www.navcen.uscg.gov/lnm.  Vessels operating in ports and waterways in several districts will have to obtain the Local Notice to Mariners from each district in order to be fully informed.

Special Notice to Mariners (SNM)

The Special Notice to Mariners is an annual publication containing important information for the mariners transiting the waterways of the Thirteenth Coast Guard District. Thirteenth District waterways include the seacoast from the California/Oregon border to the United States/Canadian border, and all federally navigable waterways in Idaho, Montana, Oregon and Washington.  Click here for a copy 2009 13th District Special Local Notice to Mariners (pdf)(6.5mb).

U.S. Coast Guard Navigation Center (NAVCEN) (LORAN, GPS, DGPS status, Local Notice to Mariners): http://www.navcen.uscg.gov