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Westray South Tidal Project

Project Site Annex IV

Title: Westray South Tidal Project
Developer:
Country:
Technology Type:
Info Updated:
July 04, 2018
Westray South Lease Option Area
Project Status: 
Planned project
Technology: 
Technology neutral
Project Scale: 
Commercial
Installed Capacity: 
Up to 200MW

1.1 Background

In 2010, SSE Renewables (SSER) was awarded an Agreement for Lease (AfL) from The Crown Estate for development rights to support a 200 megawatt (MW) tidal array in the Westray Firth, Orkney.  The AfL for the Westray South site was transferred to DP Energy in March 2014.

 

A Special Purpose Vehicle (SPV) ‘Westray South Tidal Development Ltd (WSTDL)’ has been set up to progress development of the project.

 

A pre-scoping exercise was undertaken in April 2011 when a Project Briefing Document (PBD) was issued to a wide range of stakeholders.  The objective of the PBD was to provide stakeholders with an introduction to the proposed development in order to provide an early opportunity to engage with the project development process. Feedback received from stakeholders was used to inform the subsequent request for a Scoping Opinion.

 

A formal request for a Scoping Opinion was made in October 2011 to Marine Scotland Licensing Operations Team (MS-LOT), on behalf of Scottish Ministers, and a Scoping Opinion was received in December 2011. A number of topic-specific consultations and site surveys have since been undertaken to date and these are outlined in Section 4.2 below.

 

The area was first identified as a potential development opportunity in late 2008 at which point consultation was initiated with a range of stakeholders. Feedback received has influenced a number of areas of the development process including refining the geographical extents. Consultation responses also informed baseline data acquisition and following receipt of the scoping opinion a number of EIA and technical studies were undertaken including:

  • Two years of bird and marine mammal surveys;
  • Seasonal radar surveys to support the Navigational Risk Assessment (NRA) process;
  • A full geophysical survey of the development area and cable route corridor;
  • Seven ADCP deployments; and
  • Onshore and shoreline ecological surveys.

 

WSTDL now plan to complete the Environmental Impact Assessment (EIA) and Habitats Regulations Appraisal (HRA) in order to support the necessary consent and licence application for the Project.

 

1.2 The Project

The project consists of a 200MW tidal array which would require the installation and operation of up to 200 tidal turbines. It is anticipated that the project would be built out in stages although the scale of each stage has not yet been determined. The AfL area covers water depths ranging from 25 – 54m and lies approximately 24km north of Kirkwall which is the closest sizeable port. The proposed area for tidal infrastructure deployment occupies 4.6km2 within the wider AfL area of 12.6km2.

 

The proposed project consists of the following key components:

 

  • All offshore infrastructure - primarily turbines, support structures and associated electrical infrastructure;
  • Export cable(s) to shore;
  • Cable landfall(s) and onshore cable to cable transition compound;
  • Cable transition compound
  • Onshore control building and compound;
  • Temporary works for cable landfall; and
  • Access road to cable transition and control building compound.

 

A description of these key components is provided in Section 3. 

 

There are a number of technical components that would support the proposed project which will not be developed by WSTDL and will not be assessed within the EIA, HRA and planning application.  These include:

 

  • Any upgrade to or addition to the existing electricity transmission or distribution infrastructure (both onshore and offshore) or associated works;
  • Any port/harbour upgrade/development or associated works which may be required to facilitate construction or operation and maintenance activities; and
  • Onshore laydown and maintenance facilities.

 

This approach has established precedent within Scotland. However, as a minimum, where information is available within the public domain WSTDL intends to provide supporting information on these wider activities in order to place these within the context of the Westray South project. Where required these activities shall also be assessed qualitatively within the Cumulative Impact Assessment.

 

 

1.3 This document

The purpose of this briefing note is to provide updated information regarding the Westray South Tidal Development.  In addition, the project consenting strategy is presented, and information is provided about the proposed scope of the Environmental Impact Assessment (EIA). The project has developed since a scoping opinion was received and the following information is provided:

 

  • High level overview of the proposed project;
  • An outline project design envelope;
  • A proposed consenting strategy for the project, including a list of the relevant consents and licences and project consenting timescales;
  • Approach to EIA including a list of impacts that will be considered in the Environmental Impact Assessment Report (EIAR) and the proposed approach to assessment for each; and
  • A draft list of projects that will be considered in the Cumulative Impact Assessment in the EIAR.

 

 

1.4 Briefing note structure

This briefing note is structured as follows:

 

  • Section 2: Project boundaries, approach to EIA and consenting process: refinement of geographical boundaries, list of non-project components and the proposed EIA approach and consenting strategy.
  • Section 3: Project description: includes project design envelope parameters including technology options and the onshore project components.
  • Section 4: Impacts for consideration in the ES: includes tables of impacts by receptor, the proposed approach to assessment, data requirements and progress of works/assessment to date.

 

 

2 Project boundaries, approach to EIA and consenting process

This chapter defines the geographical and technical boundaries of the EIA along with the approach that WSTDL plans to take with regards to site development and the implications for the EIA process. 

 

2.1 PROJECT Geographical boundaries

Figure 2.1 illustrates the Areas of Search (AoS) for the onshore and offshore components of the project:

 

  • Preferred development area which includes the offshore tidal generators, inter-array cables and offshore substation/hubs, indicated by the ‘preferred development area’;
  • Grid export cable corridor to shore, indicated by the ‘cable route corridor’; and
  • Onshore works, indicated by ‘onshore works AoS’ which includes:
    • Cable landfall and onshore cable to cable transition compound;
    • Cable transition compound and control building compound;
    • Temporary landfall construction works; and
    • Access road to cable transition compound and onshore control building compound.

Figure 2.1   Westray South Offshore Area of Search, offshore cable route corridor Area of Search and onshore Area of Search

1.1 Approach to EIA

1.1.1 Project design envelope

A project design envelope approach will be implemented.  The project design envelope provides a set of maximum and minimum parameters enabling WSTDL to retain scope for adaptation within the project description and seek consent for a project on the basis that the final development design is within the parameters and the environmental impacts are no greater than predicted. 

 

WSTDL’s preferred technology type for installation at the site are Horizontal Axis Tidal Turbines (HATT).  Different HATT technologies and support structures will be included within the project description, including surface and non-surface piercing structures.

 

The project design envelope and key parameters are presented in Section 3.

 

1.1.2 Consenting strategy

For the purposes of EIA and consent application the definition of the project encompasses:

  • All offshore infrastructure - primarily turbines, support structures and grid infrastructure (including potential for multiple offshore substations);
  • Grid export cable corridor;
  • Cable landfall and onshore cable to the cable transition compound;
  • Cable transition compound (including cable joint pits);
  • Onshore control building and compound;
  • Temporary construction works; and
  • Access road to cable transition compound and onshore control building compound.

 

WSTDL proposes to produce a single EIAR covering the assessment of impacts related to the project as outlined above, which includes both offshore and onshore components.  Two separate consents and licences will be sought for the various aspects of development, as illustrated in Figure 2.2.

Figure 2.2   Proposed consenting regimes

 

WSTDL intends to submit one application for the 200MW tidal array.  A single ES and Habitats Regulations Appraisal (HRA) will be submitted in support of WSTDL’s applications for both the Marine Licence and Section 36 consent through the regulator, Marine Scotland Licensing Operations Team (MS-LOT), for the offshore and onshore components (described in Section 3.1).  Permission will be sought through the determination of a Section 36 Consent under the Electricity Works (Environmental Impact Assessment) (Scotland) Regulations 2017 (as amended).

 

Two Marine Licences will be required for the offshore project (as detailed in Figure 2.2).  One Marine Licence application will be submitted for the generating stations (tidal devices) and inter-array cabling whilst a separate Marine Licence application will be submitted for the offshore platform(s) (electrical substations/hubs) and export cabling from the platform to shore.

 

Where Section 36 consent is required, a statutory provision in the Growth and Infrastructure Act 2013, which amends Section 57 of the Town and Country Planning (Scotland) Act 1997, enables Scottish Ministers to direct that planning permission is deemed to be granted for the ancillary onshore components and related onshore infrastructure.  Orkney Islands Council (OIC) will therefore be a statutory consultee for any onshore components and MS-LOT will grant associated works under deemed planning and as part of Section 36 (as illustrated in Figure 2.2).

 

Formal Pre-Application Consultation is a statutory requirement under the Marine Licensing (Pre-Application Consultation) (Scotland) Regulations 2013 for the construction of a renewable energy structure, where the total area in which the structure is to be located exceeds 10,000 square metres.  A Pre-Application Consultation (PAC) Report will therefore accompany the application.  A stakeholder engagement plan will be prepared for use by the team to manage WSTDL’s consultation activities and will incorporate the timescales and requirements for PAC consultation to ensure the regulations are met.

 

The project will also be considered in relation to the requirements of the Habitats Directive (Council Directive 92/43/EEC on the conservation of natural habitats and of wild fauna and flora) to determine whether any elements of the proposals are likely to have a significant effect on the conservation objectives of European/Natura 2000 sites, including Special Protection Areas (SPAs) and Special Areas of Conservation (SACs), and therefore whether the project would be subject to an Appropriate Assessment.  In the first instance, WSTDL will provide an HRA Screening document for an HRA to the competent authority, in this case, MS-LOT and will consult Scottish Natural Heritage (SNH).  Any further information necessary to inform the HRA for the project will be provided with the application.

 

A summary of the key project consent and licence requirements is presented in Table 2.1.

Table 2.1 Summary of project consent and licence requirements

Project Consents

Competent Authority

Relevant Components

Section 36 consent under the Electricity act 1989 (including deemed planning permission for onshore works)

Scottish Ministers (administered by Marine Scotland-Licensing Operations Team (MS-LOT))

Tidal turbines, inter-array cables, offshore substations/ hubs and onshore works

Seabed Lease under The Crown Estate Act 1961

The Crown Estate

Tidal turbines, inter-array cables, and offshore substations/hubs

Marine Licences under the Marine (Scotland) Act 2010

Marine Scotland

ML one – tidal turbines and inter-array cables

ML two – substations/hubs and export cable

Safety zones under Section 95 of the Energy Act 2004

Department for Business, Energy & Industrial Strategy (formerly DECC)

Tidal turbines and substations/hubs

Construction vessels

Habitats Regulations Appraisal (HRA) under the Conservation (Natural Habitats, &c.) Regulations 1994 and the Conservation of Habitats and Species Regulations 2010 (as amended)

Marine Scotland under advice of SNH

All project components

CAR Licence under The Water Environment (Controlled Activities) (Scotland) Regulations 2011 (as amended)*

Scottish Environment Protection Agency (SEPA)

Onshore components

European Protected Species (EPS) licence under Annex IV of the Habitats Directive, the Habitats Regulations 1994 and other species under Wildlife and Countryside Act 1981 (as amended)

Scottish Natural Heritage (SNH) (otters, bats, nesting birds) and Marine Scotland (cetaceans and basking shark)

All project components

 *Any requirement for these licences will be confirmed with the relevant Competent Authority.

 

3 Project description

3.1 Introduction

This chapter provides an overview of the technical components of the proposed development along with an overview of the associated operations and activities.  The project description aims to be as informative as possible and is based on current information.  The project design has evolved substantially and WSTDL is now ready to start the Environmental Impact Assessment (EIA) and HRA process.  As the EIA progresses, some aspects may be subject to change.  Any changes will be reported in the EIAR.  

 

The following technical components are described:

 

  • Offshore infrastructure;
    • Proposed tidal generation technologies;
    • Proposed support structures;
    • Electrical infrastructure;
    • Subsea cables (inter-array and export to shore);
    • Offshore substation(s);
  • Onshore infrastructure;
    • Cable landfall and onshore cable to cable transition compound;
    • Cable joint pits with cable transition compound;
    • Control building and compound;
    • Temporary onshore works including landfall construction compound (including potential HDD works), laydown area and potential pipe assembly corridor; and
    • Access road(s).

 

3.2 Technology envelope

The project technology envelope requires a degree of flexibility.  Support structure type and rotor diameter may vary depending on the location within the development area.  All devices selected will, however, fall into one of the categories described below in Section 3.3 and within the design and operational limits defined for the project design envelope (refer to Table 3.1) during the EIA[1].

 

Based on current understanding and technology evaluation work, devices with a rotor diameter of up to 24m capable of generating at least 1MW will be proposed for installation.  Therefore the maximum number of devices proposed may be up to 200.

 

WSTDL is proposing to use:

  • Un-shrouded multi-bladed Horizontal Axis Tidal Turbines (HATT) in combination with either a seabed mounted or floating support structure (see Figure 3.1 and
  •  Figure 3.2 respectively in Section 3.3) and/or;
  • Shrouded multi-bladed Horizontal Axis Tidal Turbines (HATT) on a seabed mounted gravity base (see Figure 3.2). 

 

The following sections describe the WSTDL technology options under consideration (Section 3.3) and the onshore project components (Section 3.4). The overall project technology envelope for the key components is presented in Table 3.1.

 

 


[1] A mixture of different tidal technology types for deployment within the offshore area of search is being considered within the project envelope.

 

Table 3.1 Project technology envelope

Project Component

Parameter(s)

Additional Comments

Tidal turbine generators

Up to 200 devices (likely range 100 - 200)

  • Bottom-mounted and/or floating Horizontal Axis Tidal Turbines (HATT)
  • Rotor diameter up to 24m
  • Minimum 1MW devices;
  • RPM 3 – 21
  • Min blade tip clearance to sea-surface – 3m
  • Open or ducted rotor
  • Potential for multiple rotors per support structure (open rotor only)
  • Fixed and pitched blade options

Various device types considered.

Potential for a number of different layout scenarios for which work is ongoing. The final layout will be determined post-consent.

Turbine support structures

Up to 200 structures (likely range 100-200)

  • Monopile foundation (drilled socket in the seabed); braced monopile (typically three or four legged); gravity base structure (pinned or unpinned) and floating (with mooring spread and anchors)
  • Gravity base extremities footprint ~30m * 40m
  • Monopile max diameter ~4m, 15m depth
  • Monopile drill cuttings released into water column
  • Moored floating structure ~70m long, 5m diameter, 3m draft (excluding support arms)

Potential for a range of support structures to be utilised. Some technology types may have more than one option.

Offshore electrical infrastructure – subsea or surface-piercing hubs

Subsea hubs (up to 20)

  • Support structure options of gravity base, monopile or pinned foundations
  • Hub dimensions estimated at 10 – 15m long and of 6 – 8m diameter          

The current technical maturity of such infrastructure is not sufficient to allow a definite description to be made at this point and so all options for offshore electrical infrastructure need to be retained.

The final development proposal could require a combination of subsea hubs with large and small surface piercing hubs.

Large surface piercing hubs (up to 2)

  • Up to 150MW per hub
  • Support structure may be monopile, jacket or floating
  • Topsides (l,w,h) ~25m * 20m * 10m
  • Worst case total structure height above LAT ~35m

 

Small surface piercing (up to 20)

  • Notional capacity of 10MW
  • Support structure may be monopile, jacket or floating
  • Topsides (l,w,h) ~15m * 15m * 10m
  • Worst case total structure height above LAT ~25m

Likely to also be utilised as navigation marks.

Inter-array cables

  • Voltage range of 690 – 33kV assumed
  • Typically ~160mm diameter or less
  • Double steel armour
  • Surface laid (no burial)
  • Possible requirement for protection and/or pinning in some locations with rock, concrete mattresses or rock anchors

Number and length of inter-array cables dependent on technology type and array layout.

Export cables

Range of 2 to 7 required depending on cable voltage rating and staging of construction:

  • 7 required if 33kV cable rating assumed (~160mm diameter, 30MW per cable)
  • Minimum of 2 required if 132kv cable rating assumed (~225mm diameter, 100MW per cable)

 

Landfall and onshore construction compound

Option 1 - Horizontal Direct Drilling (HDD)

  • Up to seven HDD bore holes each with a length of between 400 – 1800m
  • A diameter of around 2.5 times cable diameter is anticipated

 

For landfall using HDD there would be no surface works required within the inter-tidal area. For HDD a temporary onshore construction compound above MHWS of up to 105m wide (parallel to shore) by 60m is estimated to be required.

For surface laid or trenched landfall a smaller construction compound ~80m wide by 60m is estimated to be required. A cable corridor of similar width would be required from the inter-tidal zone to the construction compound.

 

 

Option 2 - Surface laid cables at landfall

  • Installed in a duct or with clamping as a means of protection from below MLWS to cable joint pits above MHWS
  • Held in place either by inherent weight, rock anchors, rock dumping or concrete mattresses, and where possible cables will be buried
  • Between upper foreshore and construction compound cables likely to be placed in excavated trenches and buried.

HDD layout corridor

  • Estimated maximum area of 100m by 280m (~2.25ha)
  • Ground restored post construction.

Temporary layout area for bore hole pipe assembly.

Area of land abutting construction compound utilised to assemble conduit for lining HDD bores.

 

Cable joint pits (CJP) and CJP compound

Up to 7 joint pits

  • Each pit approximately 15m long, 3 - 5m wide and 2m deep
  • Constructed from concrete
  • CJP compound dimensions estimated at 75m * 20m
  • Small link pits 1.5m2 adjacent to each cable joint pit
  • Only link pit manhole covers visible post ground restoration after construction

For either landfall option it is assumed that the permanent cable joint pits would be located within the footprint of the temporary construction compound as detailed above for landfall works. Ground will be restored post-construction to leave only ground level manhole covers visible within a stockproof fenced compound.

 

Control building and compound

  • Estimated compound  size of ~750m2
  • Simple infrastructure with requirement for a building to house switchgear
  • Building height estimated at maximum of 6m

Most likely located adjacent to CJP compound with interconnecting underground cables to each cable joint pit.

Access road

Access track(s) from public road to onshore works areas

  • ~320m length assuming CJP compound and control building are adjacent
  • 7m corridor with 4m running width assumed

 

Project vessels

Options include:

  • Dynamic Positioning (DP) vessels
  • Jack-up barge
  • Barge (with mooring spread)
  • Multi-cats
  • RIB

Choice of method for installation and maintenance closely linked to: Risk Assessment; metocean conditions; economics; technology selection; and array design. As the project progresses and technology types are decided, detailed installation methods and procedures will be able to be planned.

Construction and operational maintenance hub

Kirkwall Harbour identified as preferred hub

 

 

3.3 Tidal Technology Options

Two tidal technology support structure options are under consideration for this project:

 

3.3.1 Floating structure with Horizontal Axis Tidal Turbines (HATT)

The preferred floating tidal energy technology option for deployment at the site is the Scotrenewables SR2000 as illustrated in Figure 3.1. Other potential options may yet be considered.

Figure 3.1   Scotrenewables SR2000 Floating HATT

3.3.2 Bottom mounted HATT

Bottom mounted HATTs are also being considered for deployment. These can be either shrouded or un-shrouded in design. Both options are being considered at this stage.  Some illustrative examples of device types to be included are outlined in Figure 3.2 below, but note this is not a definitive list.  Some of these devices have a single turbine per foundation/structure and some have multiple turbines per foundation/structure.  WSTDL wishes to retain the option to deploy rotors with fixed or pitched blades.

Figure 3.2   Indicative bottom mounted HATTs: Andritz Hydro Hammerfest, Atlantis Resources and OpenHydro

 

3.4 Onshore Project components

  • The onshore project components are proposed to be situated near Tingwall in the northeast of West Mainland Orkney and include:

 

  • Cable landfall above Mean High Water Springs (MHWS);
  • Onshore underground cable route, from the inter-tidal zone to the cable joint pits within the cable transition compound;
  • Cable transition compound with cable joint pits;
  • Control building and compound;
  • Road access and associated improvements; and
  • Temporary works/facilities including temporary construction compound and laydown areas to facilitate the cable landfall and other works (including potential for HDD construction compound and HDD pipe assembly).

 

Onshore infrastructure not included within this project includes:

  • Any upgrade to or addition to the existing electricity transmission or distribution infrastructure (both onshore and offshore) or associated works;
  • Any port/harbour upgrade/development or associated works which may be required to facilitate construction or operation and maintenance activities; and
  • Onshore laydown and maintenance facilities.

 

3.4.1 Cable landfall options

Cable landfall is proposed close to Tingwall, ~560m southeast of the Tingwall ferry terminal.  The landfall options being considered are as follows:

 

  • Option 1 - Horizontal Direct Drilling (HDD) – If the HDD option was taken forward up to seven HDD bore holes each with a length of between 400 – 1800m would be required for the proposed development. A diameter of around 2.5 times the cable diameter is anticipated. HDD operations require a temporary onshore construction compound which for 7 bores would require an area of up to 105 x 60m within the onshore study area, plus a laydown area to the landward side for duct assembly.
  • Option 2 - Surface laid and/or buried cables at landfall – Within the inter-tidal zone surface laid cables represent a potential alternative to HDD and will be installed either in a duct or with clamping as a means of protection. Cables will be held in place most likely with protection measures comprising of rock dumping, concrete mattresses and/or cast iron shells). Rock anchors may also be used on areas of exposed flat rock, and where conditions permit, the cables will be buried, specifically between the upper foreshore to the cable joint pit where it is assumed that cables would be laid in excavated trenches and backfilled.

 

3.4.2 Cable joint pits and cable transition compound

For both landfall options up to seven cable joint pits would be required for the project. These would be located within a cable transition compound, itself lying within the wider temporary onshore construction compound. Each pit would measure approximately 15m in length, 3 - 5m in width and 2m in depth and would be constructed from concrete. Ground restoration of these works would be carried out post-construction with only the manhole covers of the link pits immediately adjacent to the joint pits being visible post-construction. A perimeter stockproof fence is anticipated to be placed around the transition compound.

 

 

4 Potentially significant impacts for consideration

4.1 Background

The purpose of this section is to identify those potentially significant impacts that could arise from the proposals that should be considered during the next steps of the EIA process and subsequently discussed and presented in the EIAR. The EIA Team’s proposed approach to the assessment of impacts is also presented.  To enable production of a concise document, the list of potentially significant impacts described below is generic but where baseline studies and data collation/acquisition have already been undertaken this is indicated. The scope of the assessment will continue to be refined as work progresses towards a project description upon which the final assessment will be undertaken.  Stakeholder dialogue will continue to inform this process.  

 

4.2 Identification of potentially Significant impacts for consideration in relation to EIA

The project proposals could give rise to a number of direct, indirect and cumulative impacts during construction, operation and decommissioning.  For each relevant receptor, impacts that will be considered during the EIA and discussed in the EIAR are presented for each receptor in Table 4.1 to Table 4.19.  Relevant stakeholders, listed in Appendix A, will be consulted during the next steps of the EIA process where appropriate.

 

Table 4.1 to Table 4.19 identify potential impacts for each topic, the phase they are likely to occur, work to date and the next proposed steps in the EIA process.

 

Table 4.1     Onshore geology and soils

Topic

Potentially Significant Impact

Phase

Relevant Work to Date/Status

Next Steps

Geology and soils (onshore)

Disturbance or loss of features of geological interest.

Construction and installation

Operation and maintenance

Decommissioning

Desktop assessment and walkover survey undertaken for HDD works.

No detailed or intrusive surveys undertaken to date.

 

Undertake EIA.

Impacts on soils.

Construction and installation

 

Table 4.2     Hydrology, drainage and water quality

Topic

Potentially Significant Impact

Phase

Relevant Work to Date/Status

Next Steps

Hydrology, drainage and water quality

Pollution of watercourses, groundwater, groundwater dependent terrestrial ecosystems (GWDTE).

Construction and installation

Operation and maintenance

Decommissioning

Desktop assessment and walkover survey undertaken for HDD works.

Extended Phase I habitat survey undertaken in August 2012. No further surveys are anticipated. 

 

 

Consultation with SEPA.

Assess site for presence of GWDTE (only if required).

Undertake EIA.

 

Disruption to drainage and groundwater flow.

Construction and installation

Operation and maintenance

Decommissioning

Flood risk.

Construction and installation

Operation and maintenance

Decommissioning

 

 

Table 4.3     Land use and agriculture

Topic

Potentially Significant Impact

Phase

Relevant Work to Date/Status

Next Steps

Land use and agriculture

Disruption to or loss of land use/access to land use.

Construction and installation

Operation and maintenance

Decommissioning

Desktop assessment and walkover survey undertaken for HDD works.

 

 

Review of geology and hydrology assessments.

Ongoing consultation with landowners.

Undertake EIA.

Pollution or damage to agricultural soils/changes to soil quality.

Construction and installation

Decommissioning

Changes to drainage patterns.

Construction and installation

Operation and maintenance

Decommissioning

 

Table 4.4     Onshore archaeology and cultural heritage

Topic

Potentially Significant Impact

Phase

Relevant Work to Date/Status

Next Steps

Onshore archaeology and cultural heritage

Potential for damage to or destruction of known and unknown heritage assets.

Construction and installation

Operation and maintenance

Decommissioning

Methodology for setting issued to OIC, SNH and Historic Scotland and comments received 2013.

 

 

Desk-based review and walkover site survey.

ZTVs, wireframes and site survey to assess cultural setting. Reference to SLVIA.

Consultation with County Archaeologist and HES (if required).

Undertake EIA.

Potential impact on setting of important cultural heritage features.

Construction and installation

Operation and maintenance

Decommissioning

 

 

 

Table 4.5     Terrestrial ecology

Topic

Potentially Significant Impact

Phase

Relevant Work to Date/Status

Next Steps

Terrestrial ecology

Physical disturbance or loss of terrestrial habitats due to land-take for infrastructure.

Construction and installation

Operation and maintenance

Decommissioning

Extended Phase I habitat survey undertaken in August 2012.

Otter survey undertaken in August 2012 covering the onshore AoS and surrounding 500m buffer area.

Breeding bird surveys undertaken in 2012 covering the onshore AoS and surrounding 500m buffer area.

Shoreline and coastal waters surveys undertaken in May to July 2012.

 

No further surveys anticipated.

 

Follow industry guidance for Ecological Impact Assessment (EcIA) produced by CIEEM.

Consultation with SNH and OIC.

Undertake EIA and HRA screening.

 

 

Disturbance of protected species (otters).

Construction and installation

Operation and maintenance

Decommissioning

Habitat loss (breeding birds) due to land-take for infrastructure.

Construction and installation

Operation and maintenance

Disturbance of breeding birds due to construction and installation activities.

Construction and installation

Indirect effects of accidental pollution to soils, watercourses etc.

Construction and installation

Decommissioning

 

Table 4.6     Access, traffic and transport

Topic

Potentially Significant Impact

Phase

Relevant Work to Date/Status

Next Steps

Access, traffic and transport

Impacts on current road infrastructure, verges, etc. i.e. due to abnormal loads.

Construction and installation

Decommissioning

Access requirements and estimation of movements undertaken as part of HDD feasibility study.

 

No further surveys are anticipated. 

 

 

Data gathered from existing sources, OIC road traffic counters etc. 

Utilise guidelines outlined in; Department of Transport et al., 1993; Institution of Highways and Transportation, 1994; and The Institute of Environmental Assessment (IEA) Guidance notes no.1: Guidelines for the Environmental Assessment of Road Traffic, 1993.

Undertake EIA.

Impacts on other road users.

Construction and installation

Decommissioning

Impacts on communities.

Construction and installation

Decommissioning

Improvement to local road infrastructure and access.

Construction and installation

Operation and maintenance

 

Table 4.7     Other human environment

Topic

Potentially Significant Impact

Phase

Relevant Work to Date/Status

Next Steps

Onshore noise and vibration

Effects of noise and vibration due to construction activities on local residents.

Construction and installation

Decommissioning

No surveys are anticipated. 

 

Technical report will be prepared to inform the EIA.  Scope and approach to be agreed with Environmental Health department of OIC and other key stakeholders.

Undertake EIA.

Air quality

Generation of dust during construction activities.

Construction and installation

Decommissioning

Qualitative assessment in accordance with best practice guidance of the Institute of Air Quality Management (IQAM, 2012), including relevant methodologies for the assessment and monitoring of dust.

Undertake EIA.

Carbon cost of construction.

Construction and installation

Desk-based assessment of carbon cost.

 

Carbon saving.

Operations and maintenance

Desk-based assessment of carbon saving from project life-cycle.

 

Table 4.8     Seascape, landscape and visual amenity

Topic

Potentially Significant Impact

Phase

Relevant Work to Date/Status

Next Steps

Seascape, landscape and visual

Effects on seascape (Local Coastal Character Areas).

Construction and installation

Operation and maintenance

Decommissioning

SLVIA methodology issued to OIC, SNH and Historic Scotland and comments received 2013.

 

 

Seascape, landscape and visual impact assessment (SLVIA) will be undertaken, including production of ZTVs, wireframes, site photography following best practice guidance e.g. Guidelines for Landscape and Visual Assessment (GLVIA3).

Viewpoints to be confirmed with OIC/SNH. 

Undertake site visit.

Undertake EIA.

 

 

Effects on landscape (Landscape Character Types).

Construction and installation

Operation and maintenance

Decommissioning

Effects on landscape designations.

Construction and installation

Operation and maintenance

Decommissioning

Effects on visual receptors (viewpoints).

Construction and installation

Operation and maintenance

Decommissioning

 

Effects on visual receptors (sequential views).

Construction and installation

Operation and maintenance

Decommissioning

 

Table 4.9     Socio-economics

Topic

 Potentially Significant Impact

Phase

Relevant Work to Date/Status

Next Steps

Socio-economics

Increased knowledge.

Construction and installation

Operation and maintenance

Decommissioning

Marine traffic surveys undertaken April and August 2013 (2 * 2 week periods).

Ongoing engagement with Orkney Ferries, including route deviation assessment, to inform impact assessment.

Consultation with key industry and community stakeholders.

Review of commercial fisheries, recreation and tourism, SLVIA and shipping and navigation assessments.

Assessment methodology will consider current guidance e.g. ABPmer’s socio-economic methodology and baseline for Pentland Firth and Orkney Waters Round 1 Wave and Tidal Developments (2012).

Assessment of potential effects on ferry timetabling and service provision to be undertaken.

Undertake EIA.

Clustering effect.

Energy security.

Possible carbon savings.

Quality of life.

Benefits to other marine users.

Local employment and business opportunities.

Construction and installation

Decommissioning

Displacement of existing employment.

Construction and installation

Pressure on local services and infrastructure (including ports).

Pressure on existing housing and accommodation.

Commercial fisheries impacts.

Improvements to local infrastructure.

Operation and maintenance

Effects on inter-island ferry service due to route deviations around offshore infrastructure.

 

Table 4.10   Recreation and tourism

Topic

Potentially Significant Impact

Phase

Relevant Work to Date/Status

Next Steps

Recreation and tourism

Disruption to or severance of offshore and onshore recreation or tourist activity.

Construction and installation

Operation and maintenance

 

Desk-based baseline characterisation.

Links to LVIA and Access, Traffic and Transport assessments.

Review of strategic spatial studies, consultation with local industry, organisations and community.

Undertake EIA.

Pressure on local infrastructure and services.

Construction and installation

Decommissioning

Development creating new draw for tourists.

Operation and maintenance

Industrialisation of the local landscape and seascape.

Construction and installation

Operation and maintenance

Decommissioning

 

Table 4.11   Intertidal ecology

Topic

Potentially Significant Impact

Phase

Relevant Work to Date/Status

Next Steps

Intertidal ecology

Physical disturbance or loss of intertidal habitats during cable landfall installation.

 

Construction and installation

Operation and maintenance

Decommissioning

Intertidal Phase 1 habitat survey was undertaken in August 2012.

 

No further surveys are anticipated. 

 

Follow industry guidance for Ecological Impact Assessment (EcIA) produced by CIEEM.

Consultation with SNH and OIC.

Undertake EIA.

 

Accidental introduction of invasive species from vessel operations (intertidal effects).

Construction and installation

Operation and maintenance

Decommissioning

Accidental release of chemical contaminants from devices or vessels (intertidal effects).

Construction and installation

Operation and maintenance

Decommissioning

 

Table 4.12   Coastal and physical processes

Topic

Potentially Significant Impact

Phase

Relevant Work to Date/Status

Next Steps

Geology and physical processes

(offshore)

Changes in suspended sediment concentrations and sediment deposition due to installation activities.

Construction and installation

Ground condition desktop assessment undertaken May 2009 (Halcrow).

Geophysical survey undertaken in 2012 -13 (Osiris) seabed video survey 2009 and 2012 (SSER and Aquatera).

Survey of tidal current speeds with ADCP deployment in 2012 (SSER and Partrac).

Hydrodynamic modelling (MIKE21) undertaken 2009 - 2014 (Natural Power, Black & Veatch, SSER and TCE).

Method statement issued to and reviewed by MS and SNH in 2015.

 

No further surveys are anticipated. 

 

Review of available data and hydrodynamic model.

Assessment methodology will follow latest available guidance including COWRIE, BERR etc.

Undertake EIA.

Changes in morphology due to footprint of project infrastructure.

Operation and maintenance

Changes in suspended sediment concentrations and sediment deposition due to removal activities.

Operation and maintenance Decommissioning

 

Table 4.13   Benthic and shellfish ecology

Topic

Potentially Significant Impact

Phase

Relevant Work to Date/Status

Next Steps

Benthic ecology

Accidental release of chemical contaminants from devices or vessels.

Construction and installation

Operation and maintenance

Decommissioning

Baseline data desktop review undertaken in October 2013 and summary report produced.

ROV survey of AfL (2008 and 2009) and cable route (2012) undertaken and survey reports produced.

Geophysical (including side scan sonar, SBP and multibeam data acquisition) survey of AfL and cable route corridor plus buffer 2012 - 13

Methodology issued and reviewed by MS and SNH in 2013.

 

No further surveys are anticipated. 

 

Review of seabed video data.

Review of technical reports for geology and physical processes (containing analysis of ADCP, multi-beam echo sounder, side scan sonar and sub-bottom profiling survey data). Assessment methodology will follow best practice, best available scientific understanding and relevant EIA guidance e.g. Chartered Institute of Ecology and Environmental Management (CIEEM) guidance.

 

Undertake EIA.

Increased suspended sediment and turbidity from installation of subsea infrastructure, cable landfall etc.

Construction and installation

Substrate/habitat loss/damage from installation of subsea infrastructure and cable landfall.

Construction and installation

Seabed scour around subsea infrastructure and vessel moorings.

Operation and maintenance

Colonisation of subsea infrastructure.

Operation and maintenance

Changes in water flow rates leading to downstream change in benthic habitat.

Operation and maintenance

Increased suspended sediment and turbidity from removal of subsea infrastructure.

Decommissioning

Substrate/habitat loss/damage from removal of subsea infrastructure.

Decommissioning

Accidental introduction of invasive species from vessel operations.

Construction and installation

Operation and maintenance

Decommissioning

Changes to available habitat; shellfish populations.

Operation and maintenance

 

Table 4.14   Fish ecology

Topic

Potentially Significant Impact

Phase

Relevant Work to Date/Status

Next Steps

Fish ecology

Accidental release of chemical contaminants from devices or vessels.

Construction and installation

Operation and maintenance

Decommissioning

EIA and HRA Methodology issued for comment to MS-LOT, MSS and SNH Jan 2015. Comments received during 2015.

Approach to salmon collision risk assessment issued and agreed with MSS Dec 2015 and SNH Jan 2016.

Marine Mammal (including basking shark) EIA and HRA Position Paper issued to SNH and MS in November 2014.

Initial collision risk modelling for basking shark undertaken using the Encounter Rate Model (ERM) and Collision Risk Model (CRM) in 2015.

 

No further studies required.

Review of site benthic surveys and underwater noise technical report.

Approach to PCoD for basking shark to be agreed with SNH and MSS.

 

Undertake EIA.

Substratum loss at spawning and nursery grounds.

Construction and installation

Decommissioning

Smothering of sensitive species during installation and removal of structures and cables.

Construction and installation

Decommissioning

Effects of noise and vibration (including auditory injury and disturbance) due to construction and installation activities (vessel, installation activities, etc.).

Construction and installation

Operation and maintenance

Decommissioning

Electromagnetic fields (EMF) from dynamic, inter-array and export cables (elasmobranchs).

Operation and maintenance

Collision risk (turbines); operational turbines; (basking sharks).

Operation and maintenance

Barrier to movement.

Operation and maintenance

Entanglement with mooring lines and dynamic cables.

Construction and installation

Operation and maintenance

Habitat creation.

Operations and maintenance

 

Table 4.15   Marine mammals

Topic

Potentially Significant Impact

Phase

Relevant Work to Date/Status

Next Steps

Marine mammals

Effects of noise and vibration (including auditory injury and disturbance) due to construction and installation activities (vessel, installation activities, etc.).

Construction and installation

Decommissioning

Marine Mammal EIA and HRA Position Paper issued to SNH and MS in November 2014.

Two years of boat-based line transect surveys undertaken from March 2012 to March 2014 using visual observations (MMOs) and a towed passive acoustic monitoring (PAM) array.

Initial collision risk modelling undertaken using the Encounter Rate Model (ERM) and Collision Risk Model (CRM), results completed/presented in 2015.

 

No further surveys are anticipated.

 

 

 

 

Undertake collision risk and PCOD modelling using agreed approach (consultation with SNH and MS required).

Review technical underwater noise report.  

Agree data sources with SNH and MS-LOT.

Assessment methodology will follow best practice, best available scientific understanding and relevant EIA guidance e.g. Chartered Institute of Ecology and Environmental Management (CIEEM) guidance.

Undertake HRA for Natura 2000 sites. 

Consultation with Marine Scotland, SNH and OIC.

 

Undertake EIA.

Effects of noise and vibration during device operation.

Operation and maintenance

 

Barrier effects due to presence and operation of devices.

Construction and installation

Operation and maintenance

Decommissioning

Disturbance of seals at haul-out sites (vessel activity, landfall works).

Construction and installation

Operation and maintenance

Decommissioning

Indirect effects on prey species.

Construction and installation

Operation and maintenance

Risk of collision of marine mammals with tidal devices.

Operation and maintenance

Entanglement with mooring lines and dynamic cables.

Construction and installation

Operation and maintenance

Accidental release of chemical contaminants from devices or vessels.

Construction and installation

Operation and maintenance

Decommissioning

 

Table 4.16   Marine ornithology

Topic

Potentially Significant Impact

Phase

Relevant Work to Date/Status

Next Steps

Marine ornithology

Direct disturbance (noise and visual) of birds due to vessels.

Construction and installation

Operation and maintenance

Decommissioning

Two years of boat-based surveys (following European Seabirds at Sea (ESAS) protocols) completed in 2014 (covering 2012 - 2014).

Approach to assessment issued to and reviewed by MS and SNH in 2013 and revised approach in 2015.

 

No further surveys are anticipated.

 

Collision risk modelling for diving seabirds.

Assessment methodology will follow best practice, best available scientific understanding and relevant EIA guidance e.g. Chartered Institute of Ecology and Environmental Management (CIEEM) guidance.

Undertake HRA for Natura 2000 sites. 

Consultation with Marine Scotland, SNH and OIC.

 

Undertake EIA and HRA.

Accidental release of chemical contaminants from devices or vessels.

Construction and installation

Operation and maintenance

Decommissioning

Risk of collision of diving birds with tidal devices.

Operation and maintenance

Indirect impacts caused by hydrodynamic changes to surrounding seabed habitats and associated prey species.

Operation and maintenance

 

Direct seabed habitat loss due to project footprint for infrastructure.

Operation and maintenance

 

Displacement of foraging or loafing birds due to presence and operation of the development.

Operation and maintenance

 

Habitat creation (roosting platforms).

Operation and maintenance

 

Table 4.17   Shipping and navigation

Topic

Potentially Significant Impact

Phase

Relevant Work to Date/Status

Next Steps

Shipping and navigation

Displacement of vessels due to avoidance of project/construction vessels leading to increased passing vessel-to-vessel collision.

Construction and installation

Decommissioning

Traffic surveys undertaken April and August 2013 (2 * 2 week periods).

3rd party vessel activity logged or noted during bird and marine mammal surveys and geophysical surveys.

No further surveys are proposed.

Derogation to be sought from MCA relating to age of traffic survey data.

 

 

Further local consultation to support data acquisition/ collation undertaken to date.

HIRA workshop.

Undertake Navigational Risk Assessment in line with MCA Guidance (MGN 543) and DECC Guidance (2005 & 2013).

 

Undertake EIA.

 

Collision between passing vessel and construction vessel either at the project or en-route.

Construction and installation

Decommissioning

Dropped object during construction activities at the project.

Construction and installation

Decommissioning

Man overboard during operations within the site.

Construction and installation

Operation and maintenance

Decommissioning

Passing vessel powered collision with submerged/surface-piercing device.

Operation and maintenance

Passing vessel drifting collision with submerged/surface-piercing device.

Operation and maintenance

Displacement of vessels due to avoidance of site leading to increased passing vessel-to-vessel collision.

Operation and maintenance

Fishing gear interaction with subsea equipment within the project site (e.g. device, foundation, mooring or inter-array cable).

Operation and maintenance

Vessel anchoring on or dragging anchor over subsea equipment within the project.

Operation and maintenance

Fishing gear interaction with export cable to landfall.

Operation and maintenance

Vessel anchoring on or dragging anchor over export cable to landfall.

Operation and maintenance

Loss of tidal device or part of device (e.g. component failure).

Operation and maintenance

Restricted search and rescue capability in an emergency situation or increased demand due to the project.

Operation and maintenance

Restricted oil spill response in a pollution incident or increased demand due to the project.

Operation and maintenance

 

Table 4.18   Commercial fisheries

Topic

Potentially Significant Impact

Phase

Relevant Work to Date/Status

Next Steps

Commercial fisheries*

Loss of access to fishing grounds (temporary and permanent).

Construction and installation

Operation and maintenance

Decommissioning

Methodology completed Feb 2015 (internal circulation only).

 

Data sources to be confirmed with MSS.

Review of maritime traffic survey data and NRA.

Review of TCE funded Succorfish data outputs.

Consultation with key fisheries organisations and local fishing community for scoping and geophysical survey work.

Undertake EIA.

Obstruction to regular fishing vessel routes (temporary and permanent).

Construction and installation

Operation and maintenance

Decommissioning

Change in abundance of target species.

Operation and maintenance

*Navigational safety risks associated with commercial fisheries will be captured in shipping and navigation/NRA

 

Table 4.19   Marine archaeology and cultural heritage

Topic

Potentially Significant Impact

Phase

Relevant Work to Date/Status

Next Steps

Marine archaeology and cultural heritage

Potential direct or indirect damage to or destruction of known and unknown marine historic environment assets.

Construction and installation

Operation and maintenance

Decommissioning

Geophysical survey undertaken in 2012 - 13.

Seabed video survey 2009 and 2012

Hydrodynamic modelling (MIKE21) undertaken 2009 - 2014

 

No further surveys are anticipated.

 

Technical baseline report.

Review of geophysical data (MBES, side-scan sonar, magnetometer, seabed ROV surveys etc.) and coastal process modelling.

Latest codes of practice, professional guidance and standards will be followed including those issued by The Crown Estate, Wessex Archaeology and Joint Nautical Archaeology Policy Committee.

Undertake EIA.

 

 

 

4.3 Cumulative and in-combination effects

Potential cumulative impacts may arise from the project with other similar projects and/or activities, and in-combination with other types of projects and/or activities.  Relevant projects may include operational, consented and proposed projects in the planning system, whilst relevant activities would include those for which a marine licence is required. Cumulative impacts that will be considered in this EIA relate to impacts due to the project and:

 

  • Existing wave and tidal energy projects in the Pentland Firth and Orkney Waters and other projects in the scoping process or beyond;
  • Existing sea and seabed users e.g. wind farms, marine aggregate extraction, oil and gas; and
  • Existing onshore infrastructure, including wind farms and other grid connection infrastructure projects.

 

4.3.1 Projects to include in the Westray South tidal array CIA

Developments in the area that may have connectivity with WSTDL project include:

 

  • EMEC, Fall of Warness;
  • BTAL offshore project;
  • SHE-T Orkney Caithness project (Orkney substation and project onward grid connection); and
  • Onshore renewable developments.

 

  • Increased suspended sediment and turbidity from installation of subsea infrastructure in inshore waters
  • Decrease in water flow leading to change in benthic habitat downstream of devices
  • Introduction of marine non-natives.
  • Changes to sediment regime as a result of physical structures on the seabed
  • Changes to sediment regime as a result of energy extraction
  • Changes to seabed morphology

 

 

Location: 

The project is located in the Westray Firth off the coasts of Eday, Egilsay and Rousay. The AfL area covers water depths ranging from 25 – 54m and lies adjacent to the European Marine Energy Centre’s (EMEC) Fall of Warness tidal test site, approximately 24km north of Kirkwall.

 

Coordinates: The coordinates in which the Agreement for Lease area lies are listed below:

  • 59° 12’ 19” N 002° 54’ 20” W
  • 59° 11’ 20” N 002° 51’ 43” W
  • 59° 10’ 06” N 002° 50’ 45” W
  • 59° 09’ 02” N 002° 50’ 59” W
  • 59° 09’ 14” N 002° 52’ 30” W
  • 59° 10’ 29” N 002° 53’ 15” W
  • 59° 11’ 02” N 002° 55’ 23” W

 

Key Environmental Issues: 

 

 ​​​

Westray South Tidal Project is located in United Kingdom.

Baseline Assessment: Westray South Tidal Project

ReceptorStudy Description Design and Methods Results Status
  • Fisheries

Loss of access to fishing grounds, during Installation, operation and maintenance.

Desk based study.

There is a significant chance the Westray project will reduce access points for fishermen. It is known that the AfL area and the wider area is actively used by both creel and dive fishermen.

Ongoing
  • Fisheries

Obstruction to regular fishing vessel transit routes.

Desk based study.

Larger fishing vessels use parts of the AfL as a regular transit route to/from fishing grounds. It is also assumed that smaller vessels transit the AfL area and the adjacent coastal area on a highly regular basis to reach other fishing grounds within and out with Orkney.

Ongoing
  • Infrastructure

Opportunity for expansion of existing port infrastructure.

Statistical analysis.

The main ports (Kirkwall and Hatston) are near capacity with existing users and are likely to reach capacity during busy periods due to increased activity at the EMEC tidal test sites in the coming years. Major upgrade works are about to commence at Hatston which will increase available quayside space considerably which will help to accommodate any additional vessels which will operate out of the area as part of these proposals. There are also plans to increase adjacent onshore space available for project developers in the Hatston Industrial Estate Area. Whilst no decision has been made, it is recognized that the project will require both a loadout and operational base.

Ongoing
  • Archaeology

Physical disturbance of submerged historic and prehistoric land surfaces and archaeological finds (known and unknown).

Consultation with Historic Scotland.

Potential known and unknown features within the development footprint may be disturbed during construction activities.

Ongoing
  • Noise

Disturbance to marine mammals from underwater noise generated by DP vessels and devices.

Based on available data.

Dependent on information on species and behavior in the vicinity of development – further investigation required.

Ongoing
  • Benthos

Substratum / habitat loss / damage from placement of devices and other infrastructure on the seabed, cable laying.

Site specific survey and Desk based research.

Significance of impact not known as will depend on species and habitats within the footprint and surrounding area of any infrastructure placed on the seabed will be considered further.

Ongoing
  • Fish and Fisheries

Effects on herring and sand eel populations from disturbance to spawning grounds.

Based on available data.

Further information on species present required before assessment can be made regarding disturbance due to noise or physical disturbance of the seabed impacting spawning grounds or species.

Ongoing
  • Marine Mammals

Marine mammal collision with vessels.

Based on available data.

Dependent on information on species and behavior in the vicinity of development – further investigation required.

Ongoing
  • Marine Mammals

Accidental contamination to marine mammals from vessels or devices.

N/A

Industry best practice will be followed. Risk of contamination not deemed to be significant.

Ongoing
  • Reptiles

Impact to marine reptiles.

Based on existing reports.

No records of reptiles in Orkney for 14 years, considered very rare and occasional visitor, therefore an interaction of marine reptiles with the proposed development is considered unlikely.

Ongoing
  • Birds

Collision risk from underwater turbines (These data were collected in 2010 and cover alternate 2x2km blocks of sea around Orkney and the Pentland Firth).

Based on SPA studies.

Survey and consultation will be required to establish abundance and distribution of species. However there is a general lack of understanding of the behavior of seabirds in the vicinity of turbines and potential collision risks.

Ongoing
  • Birds

Disturbance by vessel activity.

Based on SPA studies.

In order to assess this impact the extent and nature of seabird activity will need to be established. An increase in vessel activity will be most apparent during construction and installation works.

Ongoing
Reports and Papers
Research

N/A

Post-Installation Monitoring: Westray South Tidal Project

ReceptorMonitoring Program Description Design and Methods Results Status
  • Fisheries

Loss of access to fishing grounds.

Inshore fishery study.

Determine what use is made of key areas. Discuss with local fishers the implications of any disruption to any fishing activity. Establish the relative value of catch for the relevant areas through consultation with local fishermen and OFA.

Underway
  • Fisheries

Disruption to regular fishing vessel transit routes.

Inshore fishery study

Use sea-routing skills, AIS and VMS data to establish options for routing and consult with OFA, local fishermen and navigational experts on potential ways forward.

Underway
  • Archaeology

Physical disturbance of submerged historic and prehistoric land surfaces and archaeological finds.

Desk reviews, reviews of bathymetric and geophysical data, stakeholder consultation.

As far as possible determine presence of indefinable features within onshore cable corridor, assessing importance of features, assess potential for submerged features within development footprint, landfall(s) and offshore cable route.

Underway
  • Military

Potential disruption to existing MoD activity.

Based on current military activity maps.

There are no exercise areas in the vicinity of the AfL likely to be affected by the proposals. Therefore, no effect on existing activity is anticipated.

Ongoing
  • Benthos

Scour around devices and other subsea infrastructure (including mooring cables as result of movement with wave and tides).

To be determined following outcomes of desk based research, survey and consultation, will be considered when micro siting of devices.

To be determined following outcomes of desk based research, survey and consultation. Review footage taken during installation to validate predictions (operations will most likely be monitored).

Ongoing
  • Fish and Fisheries

Effects on herring and sand eel populations.

Based on current data.

Determine the extent of herring and sand eel spawning/nursery.

Ongoing
Reports and Papers
Research N/A
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