Semi-submerged
Also written: awash
Floating at or just below the surface, so hard to see by eye or radar.
A semi-submerged object floats with most of its bulk below the waterline: a container, a capsized hull, a log. It returns little or no radar echo and can be invisible from the bridge in any sea, which is why warnings call it out specifically.
"Awash" describes an object or rock whose top is at the level of the water, covered and uncovered by the waves.
What the archive shows
1,190 messages in this archive use “Semi-submerged”, the earliest issued 1986-12-08 and the latest 2026-09-07. 1 of them is in force in the latest lists we collected. A hazard reported again and again counts once per message.
The largest yearly count is 2013, with 103 messages. Collection is incomplete between 2024-05 and 2026-08-17, so 2024, 2025 and 2026 are not comparable with fully collected years.
Derelicts accounts for 926 of 1,190 recorded messages (78%), the largest warning type group in this selection.
Located messages that use it fall in 52 sea areas; the most frequent are Indian Ocean (192), South Pacific Ocean (106) and North Atlantic Ocean (102).
Its use is spread fairly evenly through the year: the busiest month, January, has 114 messages and the quietest, February, 82.
By warning series: HYDROPAC 817, HYDROLANT 144, NAVAREA IV 135 and NOAAORR 46, and 4 more.
Messages using it, by year of issue
By month of issue, all years
Where it appears · 52 sea areas
In force now · 1
- HYDROPAC 582/24 · Wrecks · Persian Gulf2024-02-19 · in force
PERSIAN GULF. U.A.E. DNC 10. PARTIALLY SUBMERGED WRECK IN VICINITY 25-11.64N 054-10.12E.
Partially submerged wreck in vicinity 25-11.64N 054-10.12E →
How it reads in recent messages
- HYDROPAC 2561/26 · Derelicts · Indian Ocean2026-09-06
EASTERN INDIAN OCEAN. 1. DERELICT 13 METER VESSEL PARTIALLY SUBMERGED AND ADRIFT IN 12-06.20S 114-19.47E AT 061100Z SEP. 2. CANCEL THIS MSG 092131Z SEP 26.
Derelict 13 meter vessel partially submerged and adrift in 12-06.20S 114-19.47E at 061100Z sep → - NAVAREA X 100/26 · Derelicts · Indian Ocean2026-09-06
CHART AUS4603 - NORTH COAST AND ADJACENT WATERS 13M UNOCCUPIED SEMI-SUBMERGED CATAMARAN ADRIFT IN POSITION 12-06.20S 114-19.47E AT 061100 UTC SEP 2026.
NAVAREA X 100/26 → - NAVAREA XII 597/26 · Derelicts · North Pacific Ocean2026-09-01
NORTH PACIFIC. 1. DERELICT 12 METER VESSEL, GREY HULL, PARTIALLY SUBMERGED AND ADRIFT IN 09-44.50N 137-14.20W AT 292320Z AUG. 2. CANCEL THIS MSG 040029Z SEP 26.
Derelict 12 meter vessel, grey hull, partially submerged and adrift in 09-44.50N 137-14.20W at 292320Z aug → - NAVAREA IV 816/26 · Derelicts · North Atlantic Ocean2026-08-22
NORTH ATLANTIC. 1. DERELICT 26 FOOT VESSEL PARTIALLY SUBMERGED AND ADRIFT IN 32-51.60N 056-35.20W AT 222025Z AUG. 2. CANCEL THIS MSG 252200Z AUG 26.
Derelict 26 foot vessel partially submerged and adrift in 32-51.60N 056-35.20W at 222025Z aug → - HYDROPAC 2401/26 · Containers · Arabian Sea2026-08-20
ARABIAN SEA. INDIA. 1. PARTIALLY SUBMERGED CONTAINER ADRIFT IN VICINITY 18-55.16N 071-55.61E AT 200400Z AUG. 2. CANCEL THIS MSG…
Partially submerged container adrift in vicinity 18-55.16N 071-55.61E at 200400Z aug → - AUSCOAST 130/26 · Other · Indian Ocean2026-04-04
SEMI-SUBMERGED MOORING LIGHTBUOY FL.W IN POSITION 20-16.32S 116-16.58E
Semi-submerged mooring lightbuoy fl.w in position 20-16.32S 116-16.58E → - HYDROPAC 1427/25 · Spills · South Pacific Ocean2025-06-03
WESTERN SOUTH PACIFIC. FIJI. DNC 06. 1. 59 METER VESSEL, PARTIALLY SUBMERGED IN 18-07.52S 178-25.57E. 2. OIL SPILL RESPONSE OPERATIONS IN PROGRESS UNTIL FURTHER…
59 meter vessel, partially submerged in 18-07.52S 178-25.57E → - NOAAORR-10873 · Spills · The Coastal Waters of Southeast Alaska and British Columbia2024-11-21
57-foot Pleasure Craft Awash; Vashon Island, WA. Vashon, WA 98070, USA. 1. On November 24, 2024, the USCG Sector…
57-foot pleasure craft awash; vashon island, wa →
Earliest in the archive
- NOAAORR-6428 · Spills · Bering Sea1986-12-08
…The vessel then shifted position and was swamped. By noon on December 2, its decks were awash in 2-4 foot seas with 25-30 knot winds. Fuel tanks believed to contain approximately…
Paul, pribilof islands, alaska →
Often in the same message
Related terms
- Lost containers
- Shipping containers lost overboard, reported floating or semi-submerged, often in groups after a single incident.
- Derelict
- An abandoned vessel still afloat and drifting, with no one on board.
- Adrift
- Loose and moving with wind and current — a vessel, container, buoy, log or anything else no longer secured.
Warning types that use it
- Containers — Shipping containers lost overboard and reported adrift or semi-submerged.
- Debris — Logs, buoys, mooring gear and other objects adrift.
- Derelicts — Abandoned, disabled or drifting vessels.
Counts cover the messages in this archive that use the term, recounted 2026-09-24; see coverage for what is collected and since when. Not for navigation — follow official NAVAREA and coastal broadcasts.