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 4176/17 · Nav aids2017-12-24 → 2018-01-20
    Platform 11/30-C, 58-05.7N 003-09.1W unlit
  2. HYDROLANT 4167/17 · Other2017-12-23 → 2018-02-03
    Unexploded ordnance in 51-19.31N 001-56.12E
  3. HYDROLANT 4157/17 · Wrecks2017-12-22 → 2018-02-02
    Fog signals at sheringham shoal wind farm 53-08N 001-10E unreliable
  4. HYDROLANT 4135/17 · Nav aids2017-12-20 → 2017-12-29
    All navigational aids at platform 48/14-PG, 53-31.2N 001-48.0E inoperative
  5. HYDROLANT 4125/17 · Nav aids2017-12-19 → 2018-05-25
    Buoys permanently removed in: a. 53-14.32N 001-27.12E
  6. HYDROLANT 4115/17 · Nav aids2017-12-19 → 2017-12-20
    Bell rock light 56-26.1N 002-23.2W unreliable
  7. HYDROLANT 4114/17 · Surveys2017-12-19 → 2017-12-20
    Underwater operations in progress until further notice by M/V deep helder in vicinity 51-19.6N 001-54.7E
  8. HYDROLANT 4047/17 · Surveys2017-12-14 → 2017-12-18
    Underwater operations in progress until further notice by M/V deep helder in vicinity of 51-19.6N 001-54.7E
  9. HYDROLANT 4028/17 · Nav aids2017-12-13 → 2018-01-03
    Platform oseberg h 60-32.9N 002-43.9E unlit
  10. HYDROLANT 3985/17 · Surveys2017-12-09 → 2017-12-11
    Underwater operations in progress until further notice by M/V deep helder in vicinity of trackline between…
  11. HYDROLANT 3946/17 · Other2017-12-07 → 2018-01-17
    Unexploded ordnance in 53-53.05N 001-39.55E
  12. HYDROLANT 3910/17 · Cable ops2017-12-04 → 2017-12-05
    Underwater operations in progress until further notice by cableship wave sentinel in vicinity 52-35.8N…
  13. HYDROLANT 3895/17 · Nav aids2017-12-02 → 2017-12-19
    Buoys permanently removed in: a. 53-14.32N 001-27.12E
  14. HYDROLANT 3888/17 · Surveys2017-12-01 → 2017-12-06
    Underwater operations in progress until further notice by M/V deep helder in vicinity of trackline between…
  15. HYDROLANT 3887/17 · Cable ops2017-12-01 → 2017-12-04
    Underwater operations in progress until further notice by cableship wave sentinel in vicinity 52-56.6N…
  16. HYDROLANT 3816/17 · Surveys2017-11-25 → 2017-11-30
    Underwater operations in progress until further notice by M/V deep helder in vicinity of trackline between…
  17. HYDROLANT 3788/17 · Cable ops2017-11-24 → 2017-11-25
    Underwater operations in progress until further notice by cableship wave sentinel in vicinity 52-56.6N…
  18. HYDROLANT 3778/17 · Nav aids2017-11-23 → 2018-01-04
    All navigational aids at platform 49/9-QC, 53-41.7N 002-37.3E inoperative
  19. HYDROLANT 3775/17 · Surveys2017-11-23 → 2017-11-25
    Underwater operations in progress until further notice by M/V deep helder in vicinity of trackline between…
  20. HYDROLANT 3765/17 · Nav aids2017-11-22 → 2018-01-05
    Noss head light 58-28.7N 003-03.0W temporarily changed to: fl w 20 sec 12 miles

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