SUBMARINE CABLES AND PIPELINES
Mariners are advised not to anchor or trawl in the vicinity of submarine cables and pipelines. 
Pipelines are not always buried and their presence may significantly reduce the charted depth. 
They may also span seabed undulations and cause fishing gear to become irrecoverably snagged, 
putting a vessel in severe danger. 

TRAFFIC SEPARATION SCHEMES AND ROUTEING
For the latest information on individual schemes and IMO mandatory routes for certain tankers 
and other vessels, see the Netherlands Coast Pilot (HP1) or ADMIRALTY Sailing Directions.

VESSEL REPORTING
For details of the Den Helder, Terschelling and IJmuiden Vessel Traffic Service, see the Netherlands Coast 
Pilot (HP1) or ADMIRALTY List of Radio Signals.

OIL AND GAS FIELDS
Production platforms and associated structures, including tanker moorings, storage tankers 
and platforms on pipelines, generally exhibit Mo(U) lights, aircraft obstruction lights, 
and audible fog signals. Unauthorized navigation is prohibited within 500 metres of all 
such structures, including storage tankers which can swing around their moorings. 
Tankers manoeuvring in the vicinity of platforms and moorings should be given a wide berth. 
For further information see the Netherlands Coast Pilot (HP1) or the Mariner's Handbook.

GAS FIELD DECOMMISSIONING
Production platforms and associated structures in the areas indicated are currently being
decommissioned. During the works, aids to navigation may be unreliable and certain features
may not be as shown. Consult local notices to mariners issued by the gas field operator 
for details of decommissioning progress.

PSSA AND WETREP
Tankers of more than 600 dwt carrying heavy crude oil or bitumen and tar
and their emulsions are required to participate in the mandatory reporting
system covering the Western European Particularly Sensitive Sea Area. For
further details, see Admiralty List of Radio Signals and the Netherlands
Coast Pilot (HP1).

MANDATORY SHIPS' ROUTEING SYSTEM DEEP WATER ROUTES
The Deep Water Routes (DW) on this chart have been specially surveyed for deep-draught vessels. 
Mariners must take into account possible changes in depths due to meteorological and other effects. 
Certain DW routes have been adopted by IMO as a Mandatory Ships' Routeing System under SOLAS Regulation V/10. 
For details see the Netherlands Coast Pilot (HP1) or Admiralty Sailing Directions.

FORMER MINED AREA
Part of this chart (east of 4°30'E) falls within a former mined area; mines could still present 
a hazard for vessels anchoring, fishing or engaged in submarine or seabed operations. 
They are not considered hazardous to surface navigation.

AREA TO BE AVOIDED (ATBA)
(54°00,9'N 4°29,5'E & 54°02,4'N 4°48,4'E)
Due to drilling and exploitation activities in the oil and gas fields, this area has been 
designated as an Area to be Avoided (This area is IMO-adopted). 
