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 2198/20 · Other2020-07-11 → 2020-07-11
    Ordnance detonation in progress by M/V noordhoek pathfinder in vicinity 53-34.0N 000-38.1E
  2. HYDROLANT 2191/20 · Other2020-07-10 → 2020-07-10
    Ordnance detonation in progress by M/V noordhoek pathfinder in vicinity 53-59.9N 001-23.2E
  3. HYDROLANT 2156/20 · Nav aids2020-07-07 → 2020-07-08
    NAVTEX station cullercoats (g) 55-04.5N 001-27.8W off air 0915Z to 1530Z daily 07 and 08 jul
  4. HYDROLANT 2076/20 · Cable ops2020-06-28 → 2020-07-02
    Underwater operations by cableship sovereign until further notice in vicinity 53-17.5N 002-25.4E
  5. HYDROLANT 2068/20 · Nav aids2020-06-27 → 2020-06-29
    Cgoc aberdeen mf r/t services at greg ness site 57-07.6N 002-03.2W unreliable
  6. HYDROLANT 2067/20 · Surveys2020-06-27 → 2020-07-21
    Survey operations in progress until 31 jul by M/V bgp prospector towing 12 5000 meter long cables in area…
  7. HYDROLANT 2026/20 · Cable ops2020-06-24 → 2020-06-28
    Cable operations in progress until further notice by M/V arctic hunter in vicinity of trackline joining…
  8. HYDROLANT 2003/20 · Nav aids2020-06-19 → 2020-07-31
    Light at mast 53-10.7N 002-59.1E unreliable
  9. HYDROLANT 1924/20 · Other2020-06-11 → 2020-07-23
    Leading light sectors on approaches to lowestoft harbor 52-27.7N 001-44.5E unreliable
  10. HYDROLANT 1922/20 · Other2020-06-11 → 2020-06-11
    Leading light sectors on approaches to lowestoft harbour 52-27.7N 001-45.5E unreliable
  11. HYDROLANT 1916/20 · Other2020-06-11 → 2020-07-13
    Anchors, 1500 meter cable, marked by buoys in: a. 56-38.6N 002-20.2W
  12. HYDROLANT 1863/20 · Wrecks2020-06-03 → 2020-07-15
    Dangerous wreck, least depth 23 meters, in 55-04.21N 001-20.39E
  13. HYDROLANT 1857/20 · Nav aids2020-06-02 → 2020-06-03
    Ruytingen sw buoy 51-04.3N 001-45.8E missing
  14. HYDROLANT 1837/20 · Nav aids2020-06-01 → 2020-06-05
    Platform 44/26A 54-03.6N 002-04.7E all aids to navigation unreliable
  15. HYDROLANT 1754/20 · Cable ops2020-05-25 → 2020-08-04
    Underwater operations in progress until further notice by cableship ile de batz in area bound by 58-50N…
  16. HYDROLANT 1686/20 · Nav aids2020-05-17 → 2020-05-18
    Holm of skaw light 60-49.9N 000-46.3W unlit
  17. HYDROLANT 1622/20 · Nav aids2020-05-13 → 2020-05-15
    RACON at tarbat ness light 57-51.9N 003-46.6W at reduced power
  18. HYDROLANT 1603/20 · Surveys2020-05-12 → 2020-07-01
    Survey operations in progress until further notice by M/V ramform vanguard towing 14 5.4 mile long cables in…
  19. HYDROLANT 1600/20 · Nav aids2020-05-11 → 2020-05-12
    Platform 49/19 bg, 53-24.1N 002-39.3E unlit
  20. HYDROLANT 1595/20 · Nav aids2020-05-10 → 2020-05-12
    Foxtrot 3 lightship 51-23-48N 002-00-36E 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.