Navigational Interference – Installations 

For information on the impact of Brexit on oil and gas environmental legislation, please refer to the pdf document downloadable from the Home Page.

Key Legislation:

For more detail on the Legislation relevant to this page, please use the following links:

Supporting legislation:
Consent Needed:

Prior written consent of the Secretary of State for the Department for Energy Security and Net Zero is required for the siting of the offshore installation – whether mobile or permanent – in any part of the UKCS. A Consent to Locate (CtL) is required for the following:

  • Mobile Installations, e.g. MoDUs, Flotels, Crane Barges
  • Mobile Vessels, e.g. Well Intervention Vessels, Well Operations Vessels
  • Permanent/Fixed Installations, e.g. Manned Platforms, NUIs, FPSOs, FSUs, Production Buoys
  • Permanent/Fixed Structures, e.g. Well Templates, Wellheads and Xmas Trees
  • Pipeline and Cable Systems, e.g. Oil and Gas Pipelines, Water Injection Pipelines, Power Cables and Umbilicals
  • Other Operations, e.g. Installation of Surface Buoys and Moorings

New applications for CtLs for mobile installations, mobile vessels and permanent/fixed installations must be supported by a Vessel Traffic Survey (VTS) and, if the shipping density is high, they should also be supported by a Collision Risk Assessment (CRA).

Construction operations associated with CtLs for permanent/fixed structures and pipeline and cable systems must be supported by a Vessel Traffic Survey (VTS) and, if the shipping density is high, should also be supported by a Collision Risk Assessment (CRA), unless they are covered by a related application, consent or consent variation, e.g. a CtL to cover MoDU or crane barge operations. The seabed structures and associated deposits do not require a VTS or CRA.

For a CtL for Other operations applications that have any sea surface structures or operations that will involve a vessel being physically connected to the seabed or subsea infrastructure for a significant period and which are unable to disconnect and move away immediately in an emergency, then the application may require to be supported by a Vessel Traffic Survey (VTS) and, if the shipping density is high, may also require to be supported by a Collision Risk Assessment (CRA).

There are a number of operations that are excepted under Section 77(1) of the MCAA that may require a CtL if undertaking the operations would result, or be likely to result, in an obstruction or danger to navigation (during or subsequent to the operation). A list of the operations that may apply can be found on page 14 of the draft guidance document.

There are also specific requirements around navigational issues for decommissioning programmes (see Decommissioning – Navigation)

How to Apply:

To apply for a Consent to Locate (CtL) in relation to offshore oil and gas operations, offshore gas storage and unloading operations and offshore elements of Carbon Capture and Storage operations, either a SAT must be created in association with the MAT for the proposed operation or a standalone application can be created on the UK Oil Portal. Multiple CtL SATs can be applied for in association with one MAT, providing they relate to the same general location.In considering an application for consent the Department for Energy Security and Net Zero has to evaluate the risk to shipping which may arise from the installation of facilities of all kinds including pipelines, and measures to reduce such risks. The following aspects are considered:

  • Evidence of shipping movements in the vicinity of the proposed operations
  • The impact of likely changes in shipping movements as a consequence of the operations
  • Any constraints that would be imposed on local navigation as a consequence of the operations
  • Collision risks with respect to vessels and the operations, and between vessels as a result of the action taken to avoid the operations
  • The reduction in risk as a consequence of the implementation of mitigation measures

Guidance is available on the Department for Energy Security and Net Zero website.

Disused Pipeline Notification – Updated

The Department for Energy Security and Net Zero requires operators to submit details of pipelines or sections of pipelines that are to be taken out of use.

The disused pipelines notification has been updated to include more specific requirements on the information to be provided. The form is available on the Department for Energy Security and Net Zero website.

Who to Apply to: CtL SATs are submitted via the UK Oil Portal under the appropriate MAT or as a standalone application. There are opportunities to upload supporting documents where relevant on the UK Oil Portal. Any subsequent updates or variations will have to be submitted by creating an update or variation on the UK Oil Portal. Operators will need to be registered with the Department for Energy Security and Net Zero for access to the Portal. To set up a UK Oil Portal Account, contact the Department for Energy Security and Net Zero OED Environmental Management Team at Any problems with PETS submission contact the Department for Energy Security and Net Zero OED EMT by email at Note: DECC (now Department for Energy Security and Net Zero) took over responsibility for the Coast Protection Act 1949 Regulations for offshore oil and gas installations in October 2005. Since then, DECC (now Department for Energy Security and Net Zero) had been issuing ‘Consents to Locate’ (CtLs) under Part II of Section 34 of the CPA on behalf of the Department for Transport (DfT). As of April 2011, the CtL provisions of Section 34 of the CPA were incorporated into The Marine and Coastal Access Act 2009 (MCAA).
When to Apply: Applications should be submitted at least 28 days prior to the start of the proposed operations.Applications for larger projects, such as new permanent or fixed installations or large pipelines (greater than 40 km in length and 800 mm in diameter), or projects where there are likely to be significant navigational issues, should be submitted as soon as possible and in advance of the normal 28-day assessment period. EMT will endeavour to deal with urgent applications within a shorter time period, but cannot guarantee that the CtL will be issued to meet the applicant’s requirements. EMT will acknowledge receipt by e-mail, detailing the reference number allocated to the application and the organisations that have been consulted.
Fixed Installations:

It is preferred and less problematic to operators and the Department for Energy Security and Net Zero if applications for new developments address all the facilities to be placed rather than a series of piecemeal applications. Consent can then be given to cover the whole operation, e.g. template, drilling, jacket, topsides, pipelines, etc. Difficulty has arisen in the past for some operators where uncontroversial seabed works have been put forward for consent before and without details of more sensitive surface works. A limited consent, e.g. for exploratory drilling only does not imply that consent will necessarily be given for other operations at the same site.

Deep Water Routes and Traffic Separation Schemes:

Consent to locate in such areas are unlikely, and if consent is given stringent conditions limiting the time allowed on site are likely to be imposed.

Dynamically Positioned Vessels: CPA consents to locate will not be required for activities involving the use of vessels maintained on station using dynamic positioning, where the vessel would be able to move off station in the event of a navigational emergency, and where the proposals will not involve any deposit or removal of materials from the seabed that would constitute a locus for application of the Coast Protection Act (CPA).Further information available from CPA Guidance Notes for Vessels (Interim) on the Department for Energy Security and Net Zero website.
General: Consent to locate may include conditions to minimise interference with navigation or fishing. For example, conditions are likely with respect to decommissioning requirements.
Decommissioning: There are specific marking and notification requirements for decommissioning programmes. More detail is available in Decommissioning – Navigation.
Monitoring: N/A
What to Report: Reporting of offshore installation movements.
How to Report:

A notice was published by the Offshore Major Accident Regulator in August 2022 which provides guidance on reporting the movements of offshore installation. The notice is available here.

The guidance details the following:

  • Reports, using the template in Annex 1 of the guidance note are to be sent to:
    • Local Helicopter bases – simultaneously, to the local helicopter bases serving the old and new locations;
    • MOD Hydrographer and Maritime and Coastguard Agency (MCA)- Notify for aspects a) to e) listed below:
      • a) the appropriate Coastguard Operations Centre (CGOC) must be given warning of movements at least 48 hours before them taking place;
      • b) when an installation being established arrives at its intended location (or intermediate position if necessary);
      • c) when a precise position has been established at the new location;
      • d) when an installation commences a move to leave UK waters; and
      • e) when an installation has left UK waters.
    • Health and Safety Executive (HSE)- notify prior to entering or leaving UK Waters;
    • Police – OEUK has agreed that operators will notify Chief Constables of the location of installations over which they exercise police jurisdiction.
    • Department for Business, Energy & Industrial Strategy (BEIS):
      • a) notify prior to entering or leaving UK Waters; and 
      • b) notify when moving from one location to another within UK Water.
Who to Report to: BEIS and MCA.
When to Report: At least 48 hours before installation tow-out is commenced.
What to do if in Breach of Consent/Authorisation: Any non-compliance with the CtL conditions relating to:

  • The provision of any lights, signals or other aids to navigation
  • The stationing of guard ships in the vicinity of the operations
  • The taking of any other measures for the purposes of, or in connection with, controlling the movements of ships in the vicinity of the operations,

must be reported immediately to BEIS, and copied to the UK Hydrographic Office and other relevant consultees, using the reporting form appended as Annex H (PDF document) of the draft guidance.

Offshore Inspection: The BEIS (then DECC) Offshore Oil and Gas Environment Unit Enforcement Policy sets out the general principles that Inspectors shall follow in relation to enforcement including prosecution.
Renewal: N/A
None at present.