North Sea

IHO sea area 4 · -4° to 12° E, 51° to 61° N

in force
3
last 12 months
3
since 1997
4,727
categories
11

In force now · 3

  1. HYDROLANT 1496/26 · Surveys2026-08-03
    Survey operations are underway in the North Sea near Norway by the vessel Ramform Hyperion towing ten 2740-meter cables, requesting a three-mile berth.
  2. HYDROLANT 1488/26 · Nav aids2026-08-01
    Medium frequency DSC and radiotelephone services are off air at Bawdsey, Cullercoats, and Gregness site. Hydrolant 1441/26 is cancelled.
  3. HYDROLANT 1477/26 · Surveys2026-07-31
    Survey operations are in progress in the North Sea off Norway, with vessel Amazon Conqueror towing eight 1609-meter cables; two-mile berth requested.

Longest in force

  1. HYDROLANT 1477/26 · Surveys2026-07-31
    Survey operations are in progress in the North Sea off Norway, with vessel Amazon Conqueror towing eight 1609-meter cables; two-mile berth requested.
  2. HYDROLANT 1488/26 · Nav aids2026-08-01
    Medium frequency DSC and radiotelephone services are off air at Bawdsey, Cullercoats, and Gregness site. Hydrolant 1441/26 is cancelled.
  3. HYDROLANT 1496/26 · Surveys2026-08-03
    Survey operations are underway in the North Sea near Norway by the vessel Ramform Hyperion towing ten 2740-meter cables, requesting a three-mile berth.

By year

97
98
99
00
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
26

By month (all years)

J
F
M
A
M
J
J
A
S
O
N
D

By category · since 1997

Nav aids2,50053%
Other66814%
Cable ops65814%
Surveys58212%
Wrecks1704%
Containers441%
Derelicts341%
Exercises321%
Debris291%
Mines90%
Missiles10%

Archive · 4,724 cancelled

  1. HYDROLANT 937/22 · Nav aids2022-04-01 → 2022-04-05
    Mid falls buoy 51-18.6N 001-47.0E unlit
  2. HYDROLANT 864/22 · Nav aids2022-03-26 → 2022-03-26
    Cromer light 52-55.5N 001-19.0E unreliable
  3. HYDROLANT 833/22 · Containers2022-03-23 → 2022-03-26
    Container adrift in vicinity 51-07.8N 001-32.0E at 230511Z mar
  4. HYDROLANT 822/22 · Surveys2022-03-22 → 2022-04-14
    Survey operations in progress until further notice by M/V stril explorer in vicinity of trackline joining…
  5. HYDROLANT 796/22 · Other2022-03-19 → 2022-03-22
    600 meter long tow cable adrift in 51-08.3N 001-36.2E at 182344Z mar
  6. HYDROLANT 703/22 · Nav aids2022-03-09 → 2022-03-10
    Cgoc shetland mf r/t services at st margaret's hope site 58-49.3N 002-57.3W off air
  7. HYDROLANT 687/22 · Nav aids2022-03-08 → 2022-03-08
    Cgoc shetland mf r/t services at st margaret's hope site 58-49.3N 002-57.4W off air
  8. HYDROLANT 659/22 · Surveys2022-03-05 → 2022-03-09
    Survey operations in progress until further notice by M/V northern franklin in vicinity of trackline joining…
  9. HYDROLANT 657/22 · Nav aids2022-03-04 → 2022-03-06
    Lunna holm light 60-27.4N 001-02.4W unlit
  10. HYDROLANT 635/22 · Surveys2022-03-03 → 2022-03-04
    Survey operations in progress until further notice by M/V egs ventus in area bound by 51-38.6N 001-47.4E,…
  11. HYDROLANT 634/22 · Nav aids2022-03-03 → 2022-03-08
    All navigational aids at platform 48/29-B 53-03.3N 001-41.2E inoperative
  12. HYDROLANT 601/22 · Surveys2022-02-28 → 2022-02-28
    Survey operations in progress until further notice by M/V northern franklin in vicinity of trackline joining…
  13. HYDROLANT 560/22 · Nav aids2022-02-25 → 2022-04-07
    Cgoc aberdeen mf dsc and r/t services at gregness site 57-07.6N 002-03.2W off air
  14. HYDROLANT 539/22 · Surveys2022-02-23 → 2022-02-23
    Survey operations in progress until further notice by M/V northern franklin in vicinity of trackline joining…
  15. HYDROLANT 532/22 · Nav aids2022-02-22 → 2022-02-26
    East goodwin lightfloat in 51-13.3N 001-36.4E unlit, RACON inoperative and off station
  16. HYDROLANT 478/22 · Nav aids2022-02-18 → 2022-02-22
    East goodwin lightfloat off station in vicinity 51-13.3N 001-36.4E and RACON inoperative
  17. HYDROLANT 440/22 · Nav aids2022-02-14 → 2022-03-24
    All navigational aids at platform 49/27-H 53-00.3N 002-12.9E inoperative
  18. HYDROLANT 343/22 · Other2022-02-03 → 2023-07-14
    Unexploded ordnance in: a. 52-25.1N 002-02.1E
  19. HYDROLANT 332/22 · Nav aids2022-02-03 → 2022-03-14
    All navigational aids at wenlock platform, 53-35.3N 002-17.7E inoperative
  20. HYDROLANT 279/22 · Nav aids2022-01-28 → 2022-01-30
    Start point light 59-16.6N 002-22.6W unreliable

Sea boundaries: Flanders Marine Institute (2018), IHO Sea Areas v3, marineregions.org (CC BY 4.0). Not for navigation — follow official NAVAREA / coastal broadcasts.