FAQs
FAQs
Here you will find answers to frequently asked questions about AQUIND Interconnector. If you cannot find an answer to your question, please use the contact details provided at the bottom of this page to get in touch with the project team.
AQUIND is a UK-registered company with the sole business of developing AQUIND Interconnector. AQUIND Interconnector is not associated with any UK or European utilities or national electricity transmission system operators.
It is estimated that AQUIND Interconnector will be capable of transmitting in excess of 17 million MWh per year between GB and France, accounting for approximately 5% and 3% of their respective total electricity consumption*.
*BEIS, Energy Consumption in the UK (ECUK) (2018):
The Project is estimated to cost £1.24bn.
The Project is to be funded through project finance and secured against the operational income (revenues).
This is not unusual for a project where securing funding is dependent on the securing of a development consent order. It is not anticipated that there will be any funding shortfalls for the Project at the time when such finance is required.
It is anticipated the Project will be operational for a minimum of 25 years, and the majority of equipment will a have useful life of up to 40 years or more.
As a project of national significance, AQUIND Interconnector is subject to the Development Consent Order (DCO) regime for nationally significant infrastructure projects (NSIPs).
AQUIND’s DCO application seeks permission to build and operate the UK elements of the project, including the installation of marine cables from the boundary of the UK Exclusive Economic Zone to the landfall at Eastney, the installation of underground cables running from Eastney to Lovedean, and the creation of a new Converter Station near the grid connection point at Lovedean. The project will include fibre optic cables and associated infrastructure.
Following the submission of the DCO application to the Planning Inspectorate (PINS) in November 2019, the Examination of the application concluded in March 2021. A decision on the DCO application is expected in October 2021.
The Examination of AQUIND’s DCO application was conducted by independent examiners, appointed by the Planning Inspectorate (PINS). The Examination of the application concluded in March 2021, and a decision is expected in October 2021.
Further information regarding the Examination is available on the Planning Inspectorate’s website at: https://infrastructure.planninginspectorate.gov.uk/projects/south-east/aquind-interconnector/?ipcsection=overview
The Government is will make the final decision on the DCO application, taking into account the local impacts.
AQUIND Interconnector is considered as a Nationally Significant Infrastructure Project (NSIP), for which local councils do not have the powers to provide planning permission for NSIPs, as these powers lie solely with national Government.
An application has been submitted to the French authorities for an environmental authorisation and AQUIND are awaiting the outcome of that process.
Lovedean substation was identified as the preferred connection location for AQUIND Interconnector following an assessment by National Grid, who have an obligation to develop and maintain an efficient, coordinated and economical electricity transmission network. The assessment considers factors such as National Grid’s knowledge of the existing network (including agreed future connections), agreed cost information, environmental considerations and other constraints associated with the Proposed Development, alongside input from AQUIND on the details of the assets to be connected.
The Converter Station needs to be located as close as possible to the substation in order to minimise the length of AC cable used as part of the Interconnector. This is because AC cables take up a much wider corridor of land when compared to DC cables. Therefore, in order to reduce the impacts of the proposals, it is favourable to maximise the use of DC cables, which take up a considerably narrower corridor. AC cables also have higher transmission losses and pose other technical challenges, meaning that a longer AC cable would reduce the benefits of the Proposed Development.
Further details regarding the converter station location selection process, including alternatives considered, are contained within the Alternatives chapter of the Environmental Statement.
Eastney was chosen as the preferred option after an extensive optioneering process which took account of a wide range of factors.
The search for an appropriate landing point began in 2014/15 with 29 possible landing points being identified between Weymouth, in the west, and Bognor Regis, in the east.
When Lovedean was identified by National Grid as the preferred grid connection point, a total of seven potential landing points were prioritised.
These landing points were then subjected to a further detailed study to assess their suitability and as a result of this work, Eastney, Hayling Island and East Wittering were shortlisted as potential landing points.
Hayling Island was subsequently removed from the shortlist. This was primarily due to the requirement to cross Chichester / Langstone Harbour at Langstone Bridge, which presented significant engineering and environmental constraints.
A more detailed review of East Wittering and Eastney locations was undertaken from a marine cable installation perspective in discussion with experienced marine installation contractors. Eastney was chosen as the preferred option as this minimised the length of the onshore cable route between the landfall location and converter station locations, which in turn minimised disruption and the impacts of the proposals.
Further details regarding the landfall selection process, including alternatives considered, are contained within the Alternatives chapter of the Environmental Statement, which is available on the Planning Inspectorate’s website.
Langstone Harbour was discounted as a potential landfall location due to the numerous environmental designations which protect the Harbour and surrounding area from development and help care for protected species.
This area is constrained by international designations, including the Chichester and Langstone Harbours Special Protection Area (‘SPA’) and Ramsar site and Solent Maritime Special Area of Conservation (‘SAC’) and part of Solent and Isle of Wight Lagoons SAC, all of which are internationally protected sites (Natura 2000 sites). Langstone Harbour is also designated as a Site of Special Scientific Interest (‘SSSI’) which are of national importance. Accordingly, the existing environment protection regulations encourage all developments to avoid such areas.
In engineering terms, the Harbour’s limited depth and composition renders it too unstable for the use of cable installation machinery. Trenching in extensive tidal mudflats is likely have significant environmental impacts on protected areas. Trenching operations would be particularly disruptive to any vessel traffic in this narrow channel – including recreational traffic, the Hayling Ferry, and marine aggregate vessels transiting to Langstone.
The Environmental Statement provides an assessment of the impacts on noise and vibration from the Proposed Development including for construction (both of cables and converter station (and buildings and works associated with it), operation and decommissioning. This is set out in Chapter 24. The assessment methodology and criteria have been agreed with the relevant local authorities. In relation to the Converter Station mitigation measures have proposed and aspects of the design and layout have been influenced by the need to minimise noise. For the operational assessment the noise modelling prediction assumes a reasonable worst-case with respect to wind speed and direction. Tonal characteristics from the operational converter station have been considered through assessment of noise levels across different frequencies. Mitigation has been proposed.
The DCO is subject to a Requirement requiring an operational noise management plan to be submitted and approved in relation to the use of the Converter Station which must include the measures and methods for monitoring operational noise and a complaints procedure. The noise management plan must be implemented and maintained for the operational period of the Converter Station.
AQUIND has submitted a Framework Construction Environmental Management Plan (CEMP) with the DCO application. The CEMP will set out the overarching principles for onshore construction process and establish good management practices to ensure that construction impacts on the public and the environment are minimised. Work specific CEMP’s will be required to be produced and approved in compliance with the Framework CEMP and the construction of the Proposed Development onshore in the UK will be required to be carried out in accordance with the relevant approved CEMP.
AQUIND has submitted a Transport Assessment (TA), a Framework Traffic Management Strategy (FTMS) and a Framework Construction Traffic Management Plan (FCTMP) as part of the DCO application.
The TA details the anticipated impact on all forms of traffic and travel during the construction phase, whilst the FTMS and FCTMP detail proposed mitigation and working practices and provides an indicative construction programme, taking into consideration environmental constraints, major events, school terms and other restrictions to minimise the impact where possible.
Works specific Traffic Management Strategies (TMS) relevant to the cable installation works will be required to be produced and approved in compliance with the FTMS and the installation of the cable onshore will be required to be carried out in accordance with the relevant approved work specific TMS.
A Framework Construction Traffic Management Plan (FCTMP) has been submitted with the Application which provides an overarching plan as to how the construction traffic and site operations will be managed for the onshore components. This will mainly relate to construction of the Converter Station. The FCTMP can be found as an appendix to Chapter 22 of the Environmental Statement on Transport.
Construction traffic using the Converter Station Area will use Junction 2 of the A3(M), B2149, A3 Portsmouth Road, Lovedean Lane and Day Lane. Construction traffic to/from the works at Anmore Road will be routed either via the Converter Station compound and Broadway Lane/Anmore Lane or directly from junction 3 A3(M), Hulbert Road, A3 London Road, B2150 Hambledon Road and Mill Road.
At the landfall location in Eastney, a Transition Joint Bay (‘TJB’) will be constructed – this will be a buried structure that contains the joints between the onshore and offshore cables. The onshore cables will enter the structure underground, and the offshore cables will leave it underground – either through a backfilled trench or through a duct installed by Horizontal Direct Drilling (‘HDD’) or similar means.
In addition up to two Optical Regeneration Stations, required in connection with the fibre optic cables which form part of the Proposed Development, will be required and is proposed to be located at the Landfall. An Optical Regeneration Station would be provided in a building would be up to 4m high and located within a securely fenced compound. This would also potentially contain auxiliary power generation equipment and a fuel tank. It is currently anticipated that the compound for an Optical Regeneration Station would have a maximum size of 17 m x 34 m. Outside the compound, it is anticipated that there will be parking for up to two vehicles for maintenance purposes. If there are two Optical Regeneration Station buildings, it would be necessary for them to be located approximately 10m apart.
The majority of cables will be installed in excavated trenches (approx. 1m deep). There are four HVDC cables and two fibre optic cables to be installed. The cables will be installed in two separate trenches (also referred to as “circuits”). There will be two HVDC cables and one fibre optic cable per circuit.
To avoid the need to keep long sections of trench open to lay the cables, cable ducts will be installed and the tranches then backfilled and resurfaced, allowing for the cables to be pulled through at a later date with relatively little impact or disruption to traffic.
Where the cables are laid in or adjacent to a highway, the installation will require traffic management measures.
In certain locations the cables will be installed via a method known as horizontal directional drilling (‘HDD’). HDD is a trenchless installation method used to cross beneath areas where conventional construction methods cannot be used due to engineering or environmental constraints, where other methods may cause damage, or where access is restricted.
The cable ducts will be installed in sections of approximately 100m. Typically, the installation rate for cable ducts per circuit (or trench) is approximately 18m to 30m per day in urban areas and up to 50m per day across open land. It is estimated that it could take an average of 1 week to install the cable ducts for a 100m section and it is anticipated that up to six 100m sections on the cable route may be constructed at the same time, reducing the overall period of installation.
Cables are to be installed under the allotments and Milton Locks Nature Reserve via a process known as Horizontal Directional Drilling (HDD), which will take place between the car park located west of the Thatched House Pub and the grassed area east of Kingsley Road. This approach allows the cables to be installed deep underground with no planned impact at surface level.
The cables that AQUIND will install along the Onshore Cable Route will be delivered and laid in sections between joint bays at different locations along the route. The locations of the joint bays will be determined as part of the detailed design process and will depend on physical characteristics such as space availability, as well as minimising impact when maintenance is required. However, there will not be any joint bays located on the allotments or the adjacent Milton Locks Nature Reserve, with the joint bays located at the drilling locations at the car park located west of the Thatched House Pub and the grassed area east of Kingsley Road.
This installation method is tried and tested on numerous other cabling projects around the world.
There should be no impact on any allotment plots during the construction or operation of AQUIND Interconnector.
The documents submitted in support of the application identify bentonite as a core drilling fluid, and although the risk of a bentonite breakout has been assessed as small to negligible, it cannot be completely ruled out. Bentonite is a clay-based product commonly used in the HDD process to maintain viscosity, and it also works to seal permeable soils thereby preventing fluid invasion into any surrounding rock or soil. It is approved by the Government’s Centre for Environmental Fisheries and Aquatic Science (CEFAS) and is included on the Pose Little Or No Risk (PLONOR) list.
In order to minimise the risk, the HDD has been designed at a suitable depth within a single geological layer beneath the allotments (2.5 metres depth as it crosses into the allotments at the north and south boundaries and significantly deeper (circa 10 metres) where it passes beneath the main area of the Allotments)
In addition, a number of monitoring measures designed to minimise a risk of bentonite breakouts have been set out in the HDD Position Statement submitted with the application (REP1-132). These include the preparation of a drilling fluid design plan, the implementation and certain drilling techniques and monitoring requirements. All documents are available to download on the Planning Inspectorate’s webpage for the project under the ‘Documents’ tab: https://infrastructure.planninginspectorate.gov.uk/projects/south-east/aquind-interconnector/?ipcsection=docs.
In the unlikely event of a bentonite breakout, drilling will immediately halt to carry out monitoring. Any breakout will be cleaned by the specialist contractor performing HDD works. Contact information for the contractor will be provided to allotment holders in advance of the start of HDD operations.
Cables are to be installed under the allotments and Milton Locks Nature Reserve via a process known as Horizontal Directional Drilling (HDD), which will take place between the car park located west of the Thatched House Pub and the grassed area east of Kingsley Road. This approach allows cables to be installed deep underground with no impact at surface level.
To allow for inspections during construction and operation, AQUIND is seeking access rights only over existing paths within the allotments site to enable inspections during construction and the operation of the underground cables. However, as set out below, these maintenance activities will not result in any impact to the allotments.
The types of maintenance to be undertaken during the operation of AQUIND Interconnector can be classified into two categories; (1) scheduled maintenance and (2) unscheduled maintenance.
- Scheduled Maintenance – This would consist of walk over inspections of the cable route to ensure activities are not taking place above the cable route which could impacts its operation (e.g. deep excavation or piling). The frequency of the walk over surveys would typically be once per quarter. In the allotments, this would consist of a short walk over the existing paths to undertake a visual inspection of the areas which will sit above the cables.
Other scheduled maintenance activities in relation to the cable route include taking readings from a number of underground links, none of which are going to be located on the allotments as they are located at the joint bays, which are proposed at the car park located west of the Thatched House Pub and the grassed area east of Kingsley Road.
- Unscheduled Maintenance – This would consist of repairing a cable in the extremely rare event of a cable fault and would involve removing the section of cable in which the fault was present and replacing it with a new section of cable. In areas where HDD is used to install cables, the replacement would take place by removing the section of cable between the two joint bays either side of the section of cable in question. Then a new section of cable would be pulled through the underground duct already installed and the new section of cable would be jointed to the existing cables at the two joint bays in question. This means that, in the very unlikely event there was a cable fault along the section of cables to be installed under the allotments, the repair of that section would be undertaken from joint bays located off the allotments and no unscheduled maintenance activities would take place on the allotments.
It is not intended that the equipment will be laid within the boundary of any homes or gardens along the proposed cable route, and no such land is included within the order limits for this purpose. AQUIND’s intention is to locate the cables within existing highways or road verges wherever practicable. In certain locations, where there are constraints to using the highway or associated verge, it may be necessary to utilise land outside the highway.
There are areas where rights in private land are sought for cable installation or equipment. AQUIND’s land agent is liaising directly with the relevant landowners and/or their agents.
The majority of the cables will be installed in the public highway, minimising the need for private land to be acquired. However, some private land interests will be required to deliver the Proposed Development and AQUIND is committed to acquiring all interests by voluntary private agreement. AQUIND has sought powers of compulsory purchase as part of its application for development consent for in the event that it is not possible to acquire the necessary land or rights by voluntary private agreement.
Where residential landowners of houses adjoining the proposed onshore cable corridor were contacted as part of the consultation process, this was purely in their capacity as the presumed owner of highway subsoil. An easement will be acquired over the highway subsoil via compulsory acquisition in connection with the installation and use of the cables in that land, which is to be acquired without negotiation or the payment of compensation. This is because the relevant owner has no use or enjoyment of the subsoil land, is not prejudiced by the rights to be granted over it that are necessary for the Proposed Development, and because the subsoil of a highway is not recognised to have any market value.
Due to the earthed shielding of the HVAC Cables and HVDC Cables there will be no electric field present along the Onshore Cable Route. In addition, the electromagnetic field strengths of the HVDC and HVAC cables and the conversion process are significantly below the limits set by the relevant guidelines, are fully compliant with International and are fully compliant with UK health and safety standards.
AQUIND has submitted an Environmental Statement (ES) as part of the DCO application which reports the environmental impact assessment undertaken for the Proposed Development, identifies likely significant environmental impacts which may be caused by the Proposed Development and details proposed measures to mitigate those impacts which will be secured and required to be carried out by the DCO, if granted.
Before submitting the application, AQUIND undertook two rounds of public consultations: in January – February 2018 and in February – April 2019. A total of three and nine public exhibition events were held for each consultation respectively, where members of the public had the opportunity to view the proposals, discuss them with the project team and provide their thoughts using the feedback forms provided. In addition, for the duration of the February – April 2019 consultation, all of the consultation documents were also made available to view at ten deposit locations across Hampshire, whilst individuals could also request USBs containing the consultation documents from the project team.
Almost 1,000 local residents and stakeholders attended 12 consultation events across both consultations, with a total of 155 responses being submitted during the most recent consultation.
An overview of the consultation undertaken between February – April can be found in this Community Update Newsletter.
Since presenting its initial cable route to the local community in early 2018, the route has evolved considerably in response to the feedback received over the course of two rounds of public consultation.
Following feedback received during the statutory consultation in early 2019, and before submitting an application for a Development Consent Order (DCO) to build and operate AQUIND Interconnector, many of the more sensitive locations of the cable corridor were either significantly reduced or removed altogether.
In Portsmouth, for example, areas of Bransbury Road, Milton Road, Velder Avenue and Eastern Road were removed from the cable corridor following feedback from the local community, local authorities and other stakeholders, through the utilisation of verges and proposals for a route through Milton Common.
Over the past two years, AQUIND’s plans for the Converter Station have evolved in discussions with the relevant local authorities and stakeholders, and the site will include significant amounts of new landscaping and visual screening.
Further detail on the changes made to the proposals can be found in our October 2020 update and our Acceptance Update Newsletter.
What are the key milestones for the DCO application ?
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In February 2020, the Planning Inspectorate appointed a panel of three Inspectors, known collectively as the Examining Authority (ExA), to conduct the Examination of the Development Consent Order (DCO) application.
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The Examination of the application involved a rigorous assessment of the DCO application, including a range of public and issue-specific hearings, and concluded on 8 March 2020.
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Following the close of the Examination, the ExA had a three-month period in which to make a recommendation to the Government on whether to grant development consent.
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The Government now has a further three-months period in which to decide whether to grant development consent. A decision is expected from the Government by 21 October 2021.
Further information regarding the DCO process is available here.
In response to feedback and discussions with stakeholders, a number of alterations have been made to the proposals to address the comments received.
Some of the key changes include:
- Refinement of the cable corridor in the vicinity of Denmead, Milton and Eastney;
- Additional clarity regarding the precise landfall location; and
- Additional visual mitigation measures around the Converter Station.
Further details regarding the alterations made to the proposals can be found in our Acceptance Update Newsletter, and within Chapters 10 and 17 of the Consultation Report, which is available to view on the Planning Inspectorate’s website.
The DCO application documents are available on the AQUIND Interconnector page of the Planning Inspectorate’s (PINS) website at: https://infrastructure.planninginspectorate.gov.uk/projects/south-east/aquind-interconnector/?ipcsection=docs
AQUIND will be subject to statutory requirements in relation to compensation and where any compensation is evidenced to properly be payable, this will be required to be paid.
The Proposed Development has the potential to deliver local benefits by virtue of its construction. For example, it is estimated that around 250 people will be working on site at the peak of the construction, which should mean more custom for local services, restaurants and stores.
AQUIND is committed to mitigating the impacts of the Proposed Development. Mitigation measures are captured in Requirements (i.e. the DCO version of a planning condition), such as measures to manage disturbance caused by construction.
AQUIND agreed several development consent obligations with the local authorities. Further details can be found in the Explanatory Note.
AQUIND is a UK-registered company with the sole business of developing AQUIND Interconnector. AQUIND Interconnector is not associated with any UK or European utilities or national electricity transmission system operators.
It is estimated that AQUIND Interconnector will be capable of transmitting in excess of 17 million MWh per year between GB and France, accounting for approximately 5% and 3% of their respective total electricity consumption*.
*BEIS, Energy Consumption in the UK (ECUK) (2018):
The Project is estimated to cost £1.24bn.
The Project is to be funded through project finance and secured against the operational income (revenues).
This is not unusual for a project where securing funding is dependent on the securing of a development consent order. It is not anticipated that there will be any funding shortfalls for the Project at the time when such finance is required.
It is anticipated the Project will be operational for a minimum of 25 years, and the majority of equipment will a have useful life of up to 40 years or more.
As a project of national significance, AQUIND Interconnector is subject to the Development Consent Order (DCO) regime for nationally significant infrastructure projects (NSIPs).
AQUIND’s DCO application seeks permission to build and operate the UK elements of the project, including the installation of marine cables from the boundary of the UK Exclusive Economic Zone to the landfall at Eastney, the installation of underground cables running from Eastney to Lovedean, and the creation of a new Converter Station near the grid connection point at Lovedean. The project will include fibre optic cables and associated infrastructure.
Following the submission of the DCO application to the Planning Inspectorate (PINS) in November 2019, the Examination of the application concluded in March 2021. A decision on the DCO application is expected in October 2021.
The Examination of AQUIND’s DCO application was conducted by independent examiners, appointed by the Planning Inspectorate (PINS). The Examination of the application concluded in March 2021, and a decision is expected in October 2021.
Further information regarding the Examination is available on the Planning Inspectorate’s website at: https://infrastructure.planninginspectorate.gov.uk/projects/south-east/aquind-interconnector/?ipcsection=overview
The Government is will make the final decision on the DCO application, taking into account the local impacts.
AQUIND Interconnector is considered as a Nationally Significant Infrastructure Project (NSIP), for which local councils do not have the powers to provide planning permission for NSIPs, as these powers lie solely with national Government.
An application has been submitted to the French authorities for an environmental authorisation and AQUIND are awaiting the outcome of that process.
Lovedean substation was identified as the preferred connection location for AQUIND Interconnector following an assessment by National Grid, who have an obligation to develop and maintain an efficient, coordinated and economical electricity transmission network. The assessment considers factors such as National Grid’s knowledge of the existing network (including agreed future connections), agreed cost information, environmental considerations and other constraints associated with the Proposed Development, alongside input from AQUIND on the details of the assets to be connected.
The Converter Station needs to be located as close as possible to the substation in order to minimise the length of AC cable used as part of the Interconnector. This is because AC cables take up a much wider corridor of land when compared to DC cables. Therefore, in order to reduce the impacts of the proposals, it is favourable to maximise the use of DC cables, which take up a considerably narrower corridor. AC cables also have higher transmission losses and pose other technical challenges, meaning that a longer AC cable would reduce the benefits of the Proposed Development.
Further details regarding the converter station location selection process, including alternatives considered, are contained within the Alternatives chapter of the Environmental Statement.
Eastney was chosen as the preferred option after an extensive optioneering process which took account of a wide range of factors.
The search for an appropriate landing point began in 2014/15 with 29 possible landing points being identified between Weymouth, in the west, and Bognor Regis, in the east.
When Lovedean was identified by National Grid as the preferred grid connection point, a total of seven potential landing points were prioritised.
These landing points were then subjected to a further detailed study to assess their suitability and as a result of this work, Eastney, Hayling Island and East Wittering were shortlisted as potential landing points.
Hayling Island was subsequently removed from the shortlist. This was primarily due to the requirement to cross Chichester / Langstone Harbour at Langstone Bridge, which presented significant engineering and environmental constraints.
A more detailed review of East Wittering and Eastney locations was undertaken from a marine cable installation perspective in discussion with experienced marine installation contractors. Eastney was chosen as the preferred option as this minimised the length of the onshore cable route between the landfall location and converter station locations, which in turn minimised disruption and the impacts of the proposals.
Further details regarding the landfall selection process, including alternatives considered, are contained within the Alternatives chapter of the Environmental Statement, which is available on the Planning Inspectorate’s website.
Langstone Harbour was discounted as a potential landfall location due to the numerous environmental designations which protect the Harbour and surrounding area from development and help care for protected species.
This area is constrained by international designations, including the Chichester and Langstone Harbours Special Protection Area (‘SPA’) and Ramsar site and Solent Maritime Special Area of Conservation (‘SAC’) and part of Solent and Isle of Wight Lagoons SAC, all of which are internationally protected sites (Natura 2000 sites). Langstone Harbour is also designated as a Site of Special Scientific Interest (‘SSSI’) which are of national importance. Accordingly, the existing environment protection regulations encourage all developments to avoid such areas.
In engineering terms, the Harbour’s limited depth and composition renders it too unstable for the use of cable installation machinery. Trenching in extensive tidal mudflats is likely have significant environmental impacts on protected areas. Trenching operations would be particularly disruptive to any vessel traffic in this narrow channel – including recreational traffic, the Hayling Ferry, and marine aggregate vessels transiting to Langstone.
The Environmental Statement provides an assessment of the impacts on noise and vibration from the Proposed Development including for construction (both of cables and converter station (and buildings and works associated with it), operation and decommissioning. This is set out in Chapter 24. The assessment methodology and criteria have been agreed with the relevant local authorities. In relation to the Converter Station mitigation measures have proposed and aspects of the design and layout have been influenced by the need to minimise noise. For the operational assessment the noise modelling prediction assumes a reasonable worst-case with respect to wind speed and direction. Tonal characteristics from the operational converter station have been considered through assessment of noise levels across different frequencies. Mitigation has been proposed.
The DCO is subject to a Requirement requiring an operational noise management plan to be submitted and approved in relation to the use of the Converter Station which must include the measures and methods for monitoring operational noise and a complaints procedure. The noise management plan must be implemented and maintained for the operational period of the Converter Station.
AQUIND has submitted a Framework Construction Environmental Management Plan (CEMP) with the DCO application. The CEMP will set out the overarching principles for onshore construction process and establish good management practices to ensure that construction impacts on the public and the environment are minimised. Work specific CEMP’s will be required to be produced and approved in compliance with the Framework CEMP and the construction of the Proposed Development onshore in the UK will be required to be carried out in accordance with the relevant approved CEMP.
AQUIND has submitted a Transport Assessment (TA), a Framework Traffic Management Strategy (FTMS) and a Framework Construction Traffic Management Plan (FCTMP) as part of the DCO application.
The TA details the anticipated impact on all forms of traffic and travel during the construction phase, whilst the FTMS and FCTMP detail proposed mitigation and working practices and provides an indicative construction programme, taking into consideration environmental constraints, major events, school terms and other restrictions to minimise the impact where possible.
Works specific Traffic Management Strategies (TMS) relevant to the cable installation works will be required to be produced and approved in compliance with the FTMS and the installation of the cable onshore will be required to be carried out in accordance with the relevant approved work specific TMS.
A Framework Construction Traffic Management Plan (FCTMP) has been submitted with the Application which provides an overarching plan as to how the construction traffic and site operations will be managed for the onshore components. This will mainly relate to construction of the Converter Station. The FCTMP can be found as an appendix to Chapter 22 of the Environmental Statement on Transport.
Construction traffic using the Converter Station Area will use Junction 2 of the A3(M), B2149, A3 Portsmouth Road, Lovedean Lane and Day Lane. Construction traffic to/from the works at Anmore Road will be routed either via the Converter Station compound and Broadway Lane/Anmore Lane or directly from junction 3 A3(M), Hulbert Road, A3 London Road, B2150 Hambledon Road and Mill Road.
At the landfall location in Eastney, a Transition Joint Bay (‘TJB’) will be constructed – this will be a buried structure that contains the joints between the onshore and offshore cables. The onshore cables will enter the structure underground, and the offshore cables will leave it underground – either through a backfilled trench or through a duct installed by Horizontal Direct Drilling (‘HDD’) or similar means.
In addition up to two Optical Regeneration Stations, required in connection with the fibre optic cables which form part of the Proposed Development, will be required and is proposed to be located at the Landfall. An Optical Regeneration Station would be provided in a building would be up to 4m high and located within a securely fenced compound. This would also potentially contain auxiliary power generation equipment and a fuel tank. It is currently anticipated that the compound for an Optical Regeneration Station would have a maximum size of 17 m x 34 m. Outside the compound, it is anticipated that there will be parking for up to two vehicles for maintenance purposes. If there are two Optical Regeneration Station buildings, it would be necessary for them to be located approximately 10m apart.
The majority of cables will be installed in excavated trenches (approx. 1m deep). There are four HVDC cables and two fibre optic cables to be installed. The cables will be installed in two separate trenches (also referred to as “circuits”). There will be two HVDC cables and one fibre optic cable per circuit.
To avoid the need to keep long sections of trench open to lay the cables, cable ducts will be installed and the tranches then backfilled and resurfaced, allowing for the cables to be pulled through at a later date with relatively little impact or disruption to traffic.
Where the cables are laid in or adjacent to a highway, the installation will require traffic management measures.
In certain locations the cables will be installed via a method known as horizontal directional drilling (‘HDD’). HDD is a trenchless installation method used to cross beneath areas where conventional construction methods cannot be used due to engineering or environmental constraints, where other methods may cause damage, or where access is restricted.
The cable ducts will be installed in sections of approximately 100m. Typically, the installation rate for cable ducts per circuit (or trench) is approximately 18m to 30m per day in urban areas and up to 50m per day across open land. It is estimated that it could take an average of 1 week to install the cable ducts for a 100m section and it is anticipated that up to six 100m sections on the cable route may be constructed at the same time, reducing the overall period of installation.
Cables are to be installed under the allotments and Milton Locks Nature Reserve via a process known as Horizontal Directional Drilling (HDD), which will take place between the car park located west of the Thatched House Pub and the grassed area east of Kingsley Road. This approach allows the cables to be installed deep underground with no planned impact at surface level.
The cables that AQUIND will install along the Onshore Cable Route will be delivered and laid in sections between joint bays at different locations along the route. The locations of the joint bays will be determined as part of the detailed design process and will depend on physical characteristics such as space availability, as well as minimising impact when maintenance is required. However, there will not be any joint bays located on the allotments or the adjacent Milton Locks Nature Reserve, with the joint bays located at the drilling locations at the car park located west of the Thatched House Pub and the grassed area east of Kingsley Road.
This installation method is tried and tested on numerous other cabling projects around the world.
There should be no impact on any allotment plots during the construction or operation of AQUIND Interconnector.
The documents submitted in support of the application identify bentonite as a core drilling fluid, and although the risk of a bentonite breakout has been assessed as small to negligible, it cannot be completely ruled out. Bentonite is a clay-based product commonly used in the HDD process to maintain viscosity, and it also works to seal permeable soils thereby preventing fluid invasion into any surrounding rock or soil. It is approved by the Government’s Centre for Environmental Fisheries and Aquatic Science (CEFAS) and is included on the Pose Little Or No Risk (PLONOR) list.
In order to minimise the risk, the HDD has been designed at a suitable depth within a single geological layer beneath the allotments (2.5 metres depth as it crosses into the allotments at the north and south boundaries and significantly deeper (circa 10 metres) where it passes beneath the main area of the Allotments)
In addition, a number of monitoring measures designed to minimise a risk of bentonite breakouts have been set out in the HDD Position Statement submitted with the application (REP1-132). These include the preparation of a drilling fluid design plan, the implementation and certain drilling techniques and monitoring requirements. All documents are available to download on the Planning Inspectorate’s webpage for the project under the ‘Documents’ tab: https://infrastructure.planninginspectorate.gov.uk/projects/south-east/aquind-interconnector/?ipcsection=docs.
In the unlikely event of a bentonite breakout, drilling will immediately halt to carry out monitoring. Any breakout will be cleaned by the specialist contractor performing HDD works. Contact information for the contractor will be provided to allotment holders in advance of the start of HDD operations.
Cables are to be installed under the allotments and Milton Locks Nature Reserve via a process known as Horizontal Directional Drilling (HDD), which will take place between the car park located west of the Thatched House Pub and the grassed area east of Kingsley Road. This approach allows cables to be installed deep underground with no impact at surface level.
To allow for inspections during construction and operation, AQUIND is seeking access rights only over existing paths within the allotments site to enable inspections during construction and the operation of the underground cables. However, as set out below, these maintenance activities will not result in any impact to the allotments.
The types of maintenance to be undertaken during the operation of AQUIND Interconnector can be classified into two categories; (1) scheduled maintenance and (2) unscheduled maintenance.
- Scheduled Maintenance – This would consist of walk over inspections of the cable route to ensure activities are not taking place above the cable route which could impacts its operation (e.g. deep excavation or piling). The frequency of the walk over surveys would typically be once per quarter. In the allotments, this would consist of a short walk over the existing paths to undertake a visual inspection of the areas which will sit above the cables.
Other scheduled maintenance activities in relation to the cable route include taking readings from a number of underground links, none of which are going to be located on the allotments as they are located at the joint bays, which are proposed at the car park located west of the Thatched House Pub and the grassed area east of Kingsley Road.
- Unscheduled Maintenance – This would consist of repairing a cable in the extremely rare event of a cable fault and would involve removing the section of cable in which the fault was present and replacing it with a new section of cable. In areas where HDD is used to install cables, the replacement would take place by removing the section of cable between the two joint bays either side of the section of cable in question. Then a new section of cable would be pulled through the underground duct already installed and the new section of cable would be jointed to the existing cables at the two joint bays in question. This means that, in the very unlikely event there was a cable fault along the section of cables to be installed under the allotments, the repair of that section would be undertaken from joint bays located off the allotments and no unscheduled maintenance activities would take place on the allotments.
It is not intended that the equipment will be laid within the boundary of any homes or gardens along the proposed cable route, and no such land is included within the order limits for this purpose. AQUIND’s intention is to locate the cables within existing highways or road verges wherever practicable. In certain locations, where there are constraints to using the highway or associated verge, it may be necessary to utilise land outside the highway.
There are areas where rights in private land are sought for cable installation or equipment. AQUIND’s land agent is liaising directly with the relevant landowners and/or their agents.
The majority of the cables will be installed in the public highway, minimising the need for private land to be acquired. However, some private land interests will be required to deliver the Proposed Development and AQUIND is committed to acquiring all interests by voluntary private agreement. AQUIND has sought powers of compulsory purchase as part of its application for development consent for in the event that it is not possible to acquire the necessary land or rights by voluntary private agreement.
Where residential landowners of houses adjoining the proposed onshore cable corridor were contacted as part of the consultation process, this was purely in their capacity as the presumed owner of highway subsoil. An easement will be acquired over the highway subsoil via compulsory acquisition in connection with the installation and use of the cables in that land, which is to be acquired without negotiation or the payment of compensation. This is because the relevant owner has no use or enjoyment of the subsoil land, is not prejudiced by the rights to be granted over it that are necessary for the Proposed Development, and because the subsoil of a highway is not recognised to have any market value.
Due to the earthed shielding of the HVAC Cables and HVDC Cables there will be no electric field present along the Onshore Cable Route. In addition, the electromagnetic field strengths of the HVDC and HVAC cables and the conversion process are significantly below the limits set by the relevant guidelines, are fully compliant with International and are fully compliant with UK health and safety standards.
AQUIND has submitted an Environmental Statement (ES) as part of the DCO application which reports the environmental impact assessment undertaken for the Proposed Development, identifies likely significant environmental impacts which may be caused by the Proposed Development and details proposed measures to mitigate those impacts which will be secured and required to be carried out by the DCO, if granted.
Before submitting the application, AQUIND undertook two rounds of public consultations: in January – February 2018 and in February – April 2019. A total of three and nine public exhibition events were held for each consultation respectively, where members of the public had the opportunity to view the proposals, discuss them with the project team and provide their thoughts using the feedback forms provided. In addition, for the duration of the February – April 2019 consultation, all of the consultation documents were also made available to view at ten deposit locations across Hampshire, whilst individuals could also request USBs containing the consultation documents from the project team.
Almost 1,000 local residents and stakeholders attended 12 consultation events across both consultations, with a total of 155 responses being submitted during the most recent consultation.
An overview of the consultation undertaken between February – April can be found in this Community Update Newsletter.
Since presenting its initial cable route to the local community in early 2018, the route has evolved considerably in response to the feedback received over the course of two rounds of public consultation.
Following feedback received during the statutory consultation in early 2019, and before submitting an application for a Development Consent Order (DCO) to build and operate AQUIND Interconnector, many of the more sensitive locations of the cable corridor were either significantly reduced or removed altogether.
In Portsmouth, for example, areas of Bransbury Road, Milton Road, Velder Avenue and Eastern Road were removed from the cable corridor following feedback from the local community, local authorities and other stakeholders, through the utilisation of verges and proposals for a route through Milton Common.
Over the past two years, AQUIND’s plans for the Converter Station have evolved in discussions with the relevant local authorities and stakeholders, and the site will include significant amounts of new landscaping and visual screening.
Further detail on the changes made to the proposals can be found in our October 2020 update and our Acceptance Update Newsletter.
What are the key milestones for the DCO application ?
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In February 2020, the Planning Inspectorate appointed a panel of three Inspectors, known collectively as the Examining Authority (ExA), to conduct the Examination of the Development Consent Order (DCO) application.
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The Examination of the application involved a rigorous assessment of the DCO application, including a range of public and issue-specific hearings, and concluded on 8 March 2020.
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Following the close of the Examination, the ExA had a three-month period in which to make a recommendation to the Government on whether to grant development consent.
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The Government now has a further three-months period in which to decide whether to grant development consent. A decision is expected from the Government by 21 October 2021.
Further information regarding the DCO process is available here.
In response to feedback and discussions with stakeholders, a number of alterations have been made to the proposals to address the comments received.
Some of the key changes include:
- Refinement of the cable corridor in the vicinity of Denmead, Milton and Eastney;
- Additional clarity regarding the precise landfall location; and
- Additional visual mitigation measures around the Converter Station.
Further details regarding the alterations made to the proposals can be found in our Acceptance Update Newsletter, and within Chapters 10 and 17 of the Consultation Report, which is available to view on the Planning Inspectorate’s website.
The DCO application documents are available on the AQUIND Interconnector page of the Planning Inspectorate’s (PINS) website at: https://infrastructure.planninginspectorate.gov.uk/projects/south-east/aquind-interconnector/?ipcsection=docs
AQUIND will be subject to statutory requirements in relation to compensation and where any compensation is evidenced to properly be payable, this will be required to be paid.
The Proposed Development has the potential to deliver local benefits by virtue of its construction. For example, it is estimated that around 250 people will be working on site at the peak of the construction, which should mean more custom for local services, restaurants and stores.
AQUIND is committed to mitigating the impacts of the Proposed Development. Mitigation measures are captured in Requirements (i.e. the DCO version of a planning condition), such as measures to manage disturbance caused by construction.
AQUIND agreed several development consent obligations with the local authorities. Further details can be found in the Explanatory Note.