Broadcast Warnings and Notices to Mariners

For all offshore waters - international, domestic & foreign

Oceanographic operations, from surveying at 12 knots to rock dredging to installing deep sea moorings, frequently conflict with other marine activities and vessel transits in the area.  Means exist to broadcast and publish information about your operations and operations area(s) to warn and inform other marine activities.

By submitting information about your operations to the National Geospatial-Intelligence Agency (NGA), all marine traffic in your subject area will receive the information via the Global Maritime Distress and Safety System (GMDSS).  The information will also appear in weekly Notices to Mariners.

Two to four weeks prior to your cruise, send an email to <navsafety@nga.mil> with the following information:

  • Name of vessel(s)
  • Dates/times of operations
  • Operations area, latitudes/longitudes, etc. (OK to define an area by opposite corners, position and radius, track line, etc.)
  • Brief description of operations
  • If any equipment (such as surface buoys) will pose a hazard to surface navigation, describe the equipment, light characteristics, position and anticipated time on station.
  • Vessel contact information (Master's email address)
  • Your (Chief Scientist) contact information

When submitting this to NavSafety, please cc SIO's Ship Scheduling Office and Port Captain.

If your oceanographic operations are within US coastal waters (out to 200 miles offshore), it is important to also submit information about your operation to the Local Notice to Mariners managed and disseminated by the US Coast Guard.  For US west coast (California to Washington), out to 200 miles and including bays and harbors, please refer to the following:


For Alaska, Hawaii and US east coast, contact the SIO Port Captain.

If you are installing buoys/mooring anywhere in the eastern Pacific from California to Alaska, please refer to the following:


Additional Resources

Created: 3/22/12
Modified: 3/22/12