Eastern HVDC Link
Offshore Works CONSULTATION DOCUMENT
Submitted by: National Grid Electricity Transmission & Scottish Hydro Electric Transmission Ltd
SHETL/NGET Eastern HVDC Link Offshore (FINAL FEBRUARY 2012)
TABLE OF CONTENTS
1.0 INTRODUCTION...... 3
1.1 BACKGROUND...... 3 1.2 PURPOSE OF THE CONSULTATION DOCUMENT ...... 6 1.3 STRUCTURE OF THE DOCUMENT ...... 6 1.4 THE NEXT STAGES ...... 7 1.5 STATUTORY CONSENT PROCEDURE ...... 7 2.0 PROJECT NEED...... 9
2.1 INTRODUCTION ...... 9 2.2 STATUTORY AND LICENCE OBLIGATIONS OF TRANSMISSION LICENSEES ...... 13 3.0 PROJECT DESCRIPTION ...... 15
3.1 INTRODUCTION ...... 15 3.2 SUBSTATION...... 15 3.3 CONVERTER STATION ...... 15 3.4 UNDERGROUND HVDC CABLES ...... 15 3.5 CABLE LANDFALLS ...... 15 3.6 SUBSEA CABLES...... 15 4.0 METHODOLOGY ...... 17
4.1 OVERVIEW...... 17 4.2 REGIONAL REVIEW ...... 18 4.3 CORRIDOR REVIEW...... 19 5.0 REGIONAL REVIEW ...... 20
5.1 INTRODUCTION ...... 20 5.2 DATA COLLATION...... 20 5.3 NEAR SHORE CONSTRAINTS AND LANDFALLS ...... 24 6.0 ROUTE CORRIDOR OPTIONS (10KM WIDE CORRIDORS) ...... 35
6.1 INTRODUCTION ...... 35 6.2 CONSTRAINTS AND OPTION SUMMARY ...... 36 6.3 CORRIDOR OPTIONS ...... 36 6.4 PREFERRED ROUTE CORRIDOR OPTION ...... 64 7.0 ROUTE REFINEMENT (500M WIDE CORRIDORS)...... 65
7.1 APPROACH ...... 65 7.2 ROUTE DESCRIPTION...... 69 7.3 PREFERRED OPTIONS ...... 93
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TABLE OF FIGURES
Figure 1: Eastern HVDC Link...... 3 Figure 2: Eastern HVDC Link schematic ...... 5 Figure 3: Forecast cumulative generation capacity in the SHETL area up to year 2022/23 ...... 10 Figure 4: Forecast capacity requirements at the interface between SHETL and SP transmission systems ...... 11 Figure 5: Forecast Capability Required for Scottish Export ...... 13 Figure 6: Area of Search...... 21 Figure 7: HVDC marine designated areas and physical constraints overview map ...... 23 Figure 8: Sandford Bay near shore constraints ...... 26 Figure 9: Cruden Bay near shore constraints ...... 27 Figure 10: Bay north of Peterhead near shore constraints ...... 28 Figure 11: Lackenby near shore constraints...... 30 Figure 12: Hawthorn Pit near shore constraints...... 34 Figure 13: HVDC 10km wide corridors ...... 39 Figure 14: Conservation areas in the study area ...... 42 Figure 15: Lackenby constraints and corridors ...... 43 Figure 16: Spoil grounds in the study area ...... 46 Figure 17: Peterhead landfall options and constraints...... 47 Figure 18: Fishing activity in the study area...... 50 Figure 19: PEXAs in the study area...... 52 Figure 20: Wind farms in the study area ...... 54 Figure 21: Wrecks in the study area ...... 56 Figure 22: Geology in the study area...... 58 Figure 23: Bathymetry in the study area ...... 59 Figure 24: 500m wide route segments...... 66 Figure 25: Segments 1, 2, 2a and 3 constraints ...... 70 Figure 26: Legend for Figures 25 to 31...... 71 Figure 27: Segment 4 constraints ...... 72 Figure 28: Segments 5 and 10 constraints ...... 72 Figure 29: Segments 6, 10 to 15 and 21 constraints ...... 73 Figure 30: Segments 7, 8, 8a and 9 constraints ...... 75 Figure 31: Segments 13 and 16 to 25 constraints ...... 77 Figure 32: 500m wide corridors options. Routes HP A, HP B and HP C...... 79 Figure 33: 500m wide corridor options. Routes RS A, RS B, RS C and RS D...... 80 Figure 34: 500m wide corridor options. Routes MS A, MS B, MS C and MS D...... 81 Figure 35: Rock and till exposures along routes...... 88 Figure 36: Seabed sediment compositions along routes ...... 89 Figure 37: Relative fishing intensity along routes ...... 90 Figure 38: Route HP C, option 2a bathymetry and depth profile ...... 95
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1.0 Introduction
1.1 Background
1.1.1.1 The European Union has set a target that 15% of Europe’s energy requirements shall be met from renewable resources by 2020. The UK government’s contribution towards this target is to achieve 15% energy consumption1 from renewable sources by this date. National Grid Electricity Transmission Plc (NGET) and Scottish Hydro-Electric Transmission Ltd (SHETL) are committed to playing their part in ensuring that England and Scotland take full advantage of their renewable energy potential.
1.1.1.2 At present the electricity transmission system between Scotland and England is operating at capacity via two cross-border 400 kV transmission lines. The amount of power that needs to be moved across this part of the system continues to grow and will exceed current capacity.
Figure 1: Eastern HVDC Link
Peterhead
North East England
1.1.1.3 Accordingly, SHETL and NGET are proposing the development of an Eastern High Voltage Direct Current (HVDC) Link between Scotland and England (as shown above on Figure 1).
1.1.1.4 The Eastern HVDC Link will increase the electricity transmission capacity between the North and the South of Great Britain by approximately 2 Giga Watts (GW). It will use Direct Current (DC) technology to reinforce the existing UK transmission system in order to transmit electricity across the country in very large volumes. DC electricity is created by converting conventional Alternating Current (AC) electricity at a converter station for onwards transmission at high voltages. At the other end of the high voltage cable, DC
1 ‘The 2009 Renewable Energy Directive sets a target for the UK to achieve 15% of its energy consumption from renewable sources by 2020.’ Quoted in National Renewable Energy Action Plan for the United Kingdom Article 4 of the Renewable Energy Directive 2009/28/EC (p5).
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electricity is converted back to AC electricity at a second converter station and then transmitted through the AC system for onwards distribution to homes and businesses.
1.1.1.5 A schematic of the Eastern HVDC Link is shown in Figure 2. In both England and Scotland this will require the construction of the following electricity transmission equipment:
An HVDC converter station;
A 400kV substation and associated infrastructure; and
A corridor for two HVDC cables to land at the shoreline and connect to the converter station.
1.1.1.6 The proposed date for commencement of operational service of the Eastern HVDC Link is 2018.
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Figure 2: Eastern HVDC Link schematic
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1.2 Purpose of the Consultation Document
1.2.1.1 The primary purpose of this Consultation Document is to explain the work undertaken to date, and to refine the offshore options for the routeing, construction and operation of the Eastern HVDC Link. It is the intention of SHETL and NGET to seek feedback from key consultees at an early stage so that the project development can be appropriately informed.
1.2.1.2 It is the intention of SHETL and NGET to produce three Eastern HVDC Link consultation documents, as follows:
Scotland Onshore Works (‘Eastern HVDC Link and Associated Infrastructure Scotland Onshore Works Consultation Document’ issued on January 30, 2012);
Offshore Works (this document); and
England Onshore Works (‘Eastern HVDC Link and Associated Infrastructure England Onshore Works Consultation Document’), to be issued at a later date.
1.2.1.3 Any comments in respect of the project would be welcomed. It is requested that correspondence relating to the marine consultation in Scottish waters be directed to:
Matthew Barnette – Lead Environmental Project Manager (Scotland)
Scottish Hydro-Electric Transmission Limited
Inveralmond House
200 Dunkeld Road
Perth PH1 3AQ
Correspondence relating to relating to marine consultation in English waters should be directed to:
Hugh Smith - Consents Officer, Stakeholder & Policy Team
National Grid Electric Transmission plc
1100 Century Way, Thorpe Park, Leeds, LS15 8TU
1.2.1.4 All comments received will be considered as part of the decision making process. Initially it is proposed that an offshore fishermen’s exhibition will be held on February 28th with a public exhibition on February 29th, 2012, both at the Buchan Braes Hotel in Boddam where further comments can be made. Arrangements for public consultation in England have yet to be finalised.
1.3 Structure of the Document
1.3.1.1 The contents of this report are structured as follows:
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Section 1 – Introduction;
Section 2 – Project Need;
Section 3 – Project Description;
Section 4 – Methodology. This section sets out the methodologies used for each phase of works from the regional studies through to selection of a corridor;
Section 5 – Regional Review. This section outlines the results of the baseline assessment of offshore environmental conditions within the study area;
Section 6 – Route Corridor Options (10km wide corridors). This section identifies and appraises the 10km wide corridor options, and provides a recommendation for the preferred corridor(s); and
Section 7 – Route Refinement (500m wide corridors). This section identifies and describes the 500m wide corridor options and provides a recommendation for the selection of preferred route(s).
1.4 The Next Stages
1.4.1 Selection of the Overall Proposed Option
1.4.1.1 On conclusion of the consultation period, all comments and responses received during the period will be considered.
1.4.1.2 These responses, along with the information gathered from a non-statutory environmental appraisal process detailed below, will be collated and utilised to develop and refine the preferred option. This method of selection will minimise any potential effects the transmission infrastructure may have on the environment and people within the area, whilst providing a cost effective solution that meets technical requirements. It is intended that this process will finalise the selection of the proposed option for which consent applications will be made.
1.4.2 Non-statutory Environmental Appraisal
1.4.2.1 NGET/SHETL will undertake a non-statutory environmental appraisal for the proposed offshore works of the project. This will include desktop data searches, specialist baseline surveys, further consultation where required, and technical assessments. This process will provide a robust appraisal of any potential environmental effects of the project’s components during its construction and operation in order to identify appropriate mitigation measures to eliminate, reduce or offset these effects. All studies will be undertaken in accordance with approved methodologies and/ or industry best practice.
1.4.2.2 In order to establish the scope of the non-statutory environmental appraisal, scoping with statutory authorities and selected key consultees will be undertaken to obtain their opinion on the information that should be provided within the appraisal.
1.5 Statutory Consent Procedure
1.5.1.1 The proposed offshore development will be undertaken in accordance with the requirements of the Marine and Coastal Access Act 2009 and the Marine (Scotland) Act 2010, in relation to English and Scottish waters respectively. Separate consent applications
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will be submitted to the Marine Management Organisation (MMO) for English waters, and Marine Scotland for Scottish waters. Additional consents may be required depending upon the final routeing of the cable and will be identified in the detailed design process, and detailed in the full environmental appraisal for the cable.
1.5.1.2 In the UK the Crown Estate own the foreshore and seabed out to the 12 nautical miles territorial limit, and their consent to lay cable on the seabed will be required. Prior to obtaining the Crown Estate’s consent it will be necessary to obtain all other consents, including the statutory consents referred to above.
1.5.1.3 Where the proposed cable crosses other subsea infrastructure, there will be a requirement for crossing agreements between NGET/SHETL and the operators of this infrastructure to be concluded prior to the installation of the cable.
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2.0 Project Need
2.1 Introduction
2.1.1.1 NGET owns the high voltage national electricity transmission system in England and Wales and Scottish Power and Scottish and Southern Energy (of which SHETL is the transmission part of the business) own the system in Scotland. NGET operates the high voltage electricity system in England, Wales and Scotland and has a duty to offer terms for connection to the network when a customer makes an application for a connection. Within Great Britain there is broadly a north to south electricity flow, with greater generation in the north, and greater demand in the south.
2.1.1.2 The Eastern HVDC Link and associated onshore works are essential within SHETL’s area and in the wider network context. The Eastern HVDC Link will facilitate the connection of renewable energy generation in the north of Scotland and to enable the necessary increased power transfers through the national grid. There is a strong need case to progress these works. SHETL and NGET are developing a coordinated programme of works to deliver this reinforcement by the required date.
2.1.1.3 The need case for the Eastern HVDC Link is based on SHETL and NGET’s statutory and licence obligations as the transmission license holders. Under Section 9 of the Electricity Act 1989 ('the Act') SHETL and NGET, as transmission licence holders, have a statutory duty to develop and maintain an efficient, co-ordinated and economical system of electricity transmission. The companies also have a duty under Section 38 and Schedule 9 of the Act to have regard to the desirability of preserving amenity when developing new transmission proposals. It is essential that network security be maintained as demand and generation connected to the network changes over time.
2.1.1.4 Significant amounts of renewable energy generation have already connected to the national electricity transmission system within SHETL’s area of operations and significantly more is expected to connect in the coming years. Figure 3 shows the total volume of generation that is forecast to connect to the SHETL system in future years2. Due to the relatively low electricity demand in the SHETL area (less than 3% of Great Britain demand) the high volumes of generation will lead to higher power transfers through the SHETL network into the Scottish Central Belt and into northern England and the English part of the network.
2 The generation profile is based on the 2011 Gone Green scenario that has been developed to meet government targets for renewable generation by 2020 and beyond.
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Figure 3: Forecast cumulative generation capacity in the SHETL area up to year 2022/23
11000 Tidal 10000 Wave
9000 Offshore Wind Onshore Wind 8000 Hydro
[MW] CHP 7000 Pumped Storage 6000 CCGT Capacity
5000
4000 Generation
3000 Total
2000
1000
0
2.1.1.5 As a result of the increasing generation, SHETL is progressing a number of transmission reinforcement schemes to provide the necessary transmission capacity in accordance with the National Electricity Transmission System Security and Quality of Supply Standard (NETS SQSS). These schemes include the Beauly-Denny 400kV transmission line and various conductor replacement and substation and associated infrastructure projects north and east of Beauly. However, due to the predicted sustained increase in power flows on the transmission system, the capacity provided by these reinforcement schemes will not be sufficient to meet future requirements, hence further reinforcements are required.
2.1.1.6 The proposed additional reinforcement schemes focus on the eastern part of the SHETL transmission network. These include the East Coast onshore 400kV upgrade using existing towers from Blackhillock to Kincardine in Scottish Power’s transmission area; installation of quadrature boosters (QBs) at Blackhillock; the reconfiguration of Errochty substation and associated infrastructure; and the Peterhead to Rothienorman 400kV upgrade. Completion dates for these projects range from 2016 (for the East Coast onshore 400kV upgrade, Blackhillock QBs and Peterhead to Rothienorman 400kV upgrade), to 2017 (Errochty converter station and associated infrastructure reconfiguration) and 2018 for the Eastern HVDC Link.
2.1.1.7 Figure 4 shows the required network capacity for a central generation background. Upper and lower generation sensitivity cases have also been considered. Also shown is the actual capacity of the network illustrating the step increases in capacity that will be realised with the planned reinforcements. The required transfer level is determined in accordance with the NETS SQSS; this reflects the economic level of transmission capacity, that strikes a balance between the infrastructure investment cost, system operational costs, and system security.
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Figure 4: Forecast capacity requirements at the interface between SHETL and SP transmission systems
7500 7000 6500 6000 Required Transfer Capacity 5500 Actual Capacity of Network 5000 [MW]
4500
Capacity 4000
3500 Eastern 3000 HVDC Link Network
2500 Errochty Reconfiguration 2000 East Coast 400kV & Transmission 1500 Blackhillock QBs 1000 Beauly‐Denny 500 0 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022
2.1.1.8 Beyond 2017, the Eastern HVDC Link has been proposed as the best technical and economic solution to meet the future capacity requirements of the transmission system. The HVDC technology is particularly suited for bulk power transfer over long distances. This scheme not only reinforces the SHETL system but also increases capacity on the central and southern Scotland network, and the North of England network.
2.1.1.9 The Eastern HVDC Link works consist of the construction of a circa 2GW HVDC converter station at a suitable location at Peterhead, and the installation of subsea HVDC cables from the converter station to a location in the north of England. Associated SHETL onshore AC reinforcement works are also required to integrate the high capacity HVDC link at Peterhead to the mainland transmission system. This will be achieved through the construction of a new 400kV converter station and associated infrastructure in the vicinity of the existing 275kV substation and associated infrastructure at Peterhead, to which it will be connected. The 275kV double circuit line between Peterhead and Rothienorman 400kV converter station and associated infrastructure3 will be re-insulated to operate at 400kV using the existing towers, and connected to the new 400kV converter station and associated infrastructure at Peterhead.
2.1.1.10 To progress the development of the Eastern HVDC link, SHETL and NGET are working together to advance the design of this project with a view to completion in 2018. However due to the connection of the offshore renewable generation at Peterhead in 2016 and also to interface with the East Coast 400kV onshore project (due for completion in 2016), the new Peterhead 400kV substation and the Peterhead – Rothienorman re-insulation projects are programmed for completion in 2016.
3 The Rothienorman 400kV SubStation and associated infrastructure will be constructed as part of the East Coast 400kV upgrade, planned for completion in 2016
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2.1.1.11 On the wider transmission network, NGET and Scottish Power Transmission (SPT) are also carrying out significant reinforcement projects to support the increasing volumes of onshore and offshore renewable energy generation. These include construction of an HVDC link on the west coast between Hunterston (Scotland) and North Wales (the ‘Western HVDC Link’). SHETL is working closely with SPT and NGET in facilitating the connection and effective management of generation on its network, through coordinated, efficient, and economic transmission investment.
2.1.1.12 A study jointly commissioned by the UK government’s Department of Energy and Climate Change (DECC) and the Office for Gas and Electricity Markets (OFGEM), and progressed by the Electricity Networks Strategy Group (ENSG)4, gives an overview of the future transmission network developments required to address the European Union (EU) target for 15% of the UK’s energy to be produced from renewable sources by 2020. The ENSG reports of 20095 and 20126 include both the eastern and western HVDC links in addition to AC onshore reinforcement works.
2.1.1.13 Reinforcement to Scotland – England Connections
2.1.1.14 The existing Great Britain transmission network connecting the Scottish Power Transmission and National Grid Electricity Transmission systems comprises of two double circuit 400kV overhead line routes, one on the western side of the country and the other on the eastern side, together with some 132kV interconnection of limited capacity.
2.1.1.15 The capability of these routes is currently limited to 2.8GW (2800MW) due to system technical issues. Improvements are currently underway which will increase this capability to the order of 3.3GW. These works are due for completion in 2012.
2.1.1.16 The power transfer requirement from Scotland to England steadily increases over the next decade predominantly through the growth of renewable generation such as the offshore wind farms, and numerous onshore wind farms within Scotland. To meet this increased requirement, further high voltage equipment and system changes plus a Western HVDC link are planned to be built by 2016, and these are expected to increase boundary capability to 6.4GW.
2.1.1.17 Figure 5 shows, in green, the forecast level of required power export from Scotland over the coming decade. The actual capability of the Great Britain network, shown is red, indicates the improvements that occur as each phase of new work is connected.
4 The ENSG is jointly chaired by the Department of Energy and Climate Change (DECC) and Office of Gas and Electricity Markets (OFGEM) and its broad aim is to identify and co‐ordinate work to help address key strategic issues that affect the transition of electricity networks to a low‐carbon future. 5 Our Electricity Transmission Network: A Vision for 2020, Electricity Networks Strategy Group, March 2009, available online: http://webarchive.nationalarchives.gov.uk/20100919181607/http:/www.ensg.gov.uk/assets/1696‐01‐ensg_vision2020.pdf 6 ‘Our Electricity Transmission Network: A Vision For 2020’ (URN:11D/954), Electricity Networks Strategy Group, February 2012, available online: http://www.decc.gov.uk/assets/decc/11/meeting‐energy‐demand/future‐elec‐network/4263‐ensgfull.pdf
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Figure 5: Forecast Capability Required for Scottish Export
12000 Required Transfer Capacity
11000
Actual Capacity of Network 10000
9000
8000 RIIO 38 – Eastern HV DC Link 7000
6000 RIIO 5 – Western HV DC Link 5000 Tranmission Network Capacity [MW] 4000 RIIO 2&3 – Series & Shunt Compensation 3000 2012 2014 2016 2018 2020 2022 2024 Year
2.1.1.18 It can be seen that the green line exceeds the red line of 6.4 GW for all years after 2016. Hence further reinforcement is required, and the Eastern HVDC Link from Peterhead into North-East England is our next preferred reinforcement option. The alternative to this link would be to construct a new 400kV overhead line route, of greater than 300km length, from northern Scotland to northern England.
2.1.1.19 Figure 5 also indicates that by 2020 the forecast growth in renewable generation in Scotland may require the introduction of additional capability.
2.2 Statutory and Licence Obligations of Transmission Licensees
2.2.1.1 The primary legislation governing the electricity supply industry in Great Britain is the Electricity Act 1989 and the Utilities Act 2000. Under this legislation the Secretary of State and the Gas and Electricity Markets Authority have certain powers and duties in relation to the electricity market. In particular, the Secretary of State or the Authority may grant a licence authorising a permit to transmit electricity in an authorised area. The Electricity Act and the Utilities Act also put obligations on a licence holder, termed Statutory and Licence Obligations. These obligations include the following requirements:
To permit the development, maintenance and operation of an efficient, co-ordinated and economical system for the transmission of electricity;
To facilitate competition in the generation and supply of electricity (and without limiting the foregoing, to facilitate the licensee’s transmission system being made available to persons authorised to supply or generate electricity on terms which neither prevent nor restrict competition in the supply or generation of electricity);
To promote the security and efficiency of the electricity generation, transmission and distribution systems in England and Wales or Scotland, each taken as a whole; and
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To have regard for the environment and do what they reasonably can to mitigate any effect any proposals would have on the environment.
2.2.1.2 NGET/SHETL are the holders of the transmission licence for the England/Scotland. As part of the transmission licence, NGET/SHETL have a number of related obligations to offer non discriminatory terms for connection to the transmission system for both new generation and new sources of electricity demand. NGET/SHETL are also obliged to facilitate competition in generation connections.
2.2.1.3 In accordance with the Electricity Act 1989, electricity transmission companies are required to install and keep installed an efficient, co-ordinated and economical system of electricity supply. Paragraph 3 of Schedule 9 of the Act also requires them to:
Have regard to the desirability of preserving natural beauty, of conserving flora, fauna and geological or physiographical features of special interest and of protecting sites, buildings and objects of architectural, historic or archaeological interest; and
Do what they reasonably can to mitigate any effect which the proposals would have on the natural beauty of the countryside or on any such flora, fauna, features, sites, buildings or objects.
2.2.1.4 NGET/SHETL are therefore required to consider technical, economic and environmental issues and to achieve a balance between these.
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3.0 Project Description
3.1 Introduction
3.1.1.1 The following details the key components of the Eastern HVDC Link. Figure 2 provides a schematic diagram of how those components are related.
3.2 Substation
3.2.1.1 An important element of the project will be to provide the Eastern HVDC Link with appropriate connections to the north and the south of Great Britain in a form that is compatible with those AC transmission systems. The proposed substation in Scotland will connect into the existing transmission network via existing overhead lines or cables. The 400 kV substation will house transformers and associated equipment as well as Gas Insulated Switchgear (GIS). The overall footprint of the substation is envisaged to be approximately 170m by 110m, with a height of around 18m. In England options are being developed, and it is possible that a new 400kV substation and its connections will need to be established.
3.3 Converter Station
3.3.1.1 Prior to electricity being exported from the transmission system in Scotland there will be a requirement to convert the AC into DC. Prior to imported electricity being connected to the transmission system in England there will then be a requirement to convert the DC back into AC. In order to achieve this, specialist equipment will be required in the form of converter stations in both Scotland and England. Each converter station will be housed within an industrial type building with an envisaged footprint of 300m by 150m and an approximate height of 25m.
3.4 Underground HVDC Cables
3.4.1.1 Onshore delivery and export of the DC electricity to and from the converter stations will be via underground HVDC cables, which will interface with the offshore environment. The exact configuration of these onshore cables will be subject to detailed design analysis in consultation with specialist cable manufacturers.
3.5 Cable Landfalls
3.5.1.1 The cable landfalls are the main area of interaction between the onshore and offshore components of the project. At each landfall a large working area with a footprint in the region of 30m by 30m will be required to facilitate an underground joint bay where the onshore and offshore cables will be joined together. This underground joint bay also accommodates other temporary construction equipment required to land the subsea HVDC cable and connect it to the onshore underground HVDC cable.
3.6 Subsea Cables
3.6.1.1 Subsea HVDC cables will be routed from a landfall in Scotland to a landfall in England and will comprise the majority of the project in terms of its development footprint (albeit wholly subsea). The subsea cable will generally be similar to the onshore DC cables except that it is likely to require thicker or additional armouring to protect the cable both during and following installation. The exact configuration of the subsea cable will be subject to detailed design.
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3.6.1.2 The following section sets out the methodology used to arrive at the preferred 500m wide offshore corridor route for the Eastern HVDC Link and associated infrastructure. In accordance with SHETL and NGET’s license requirements each stage of optioneering has been guided by technical, economic and environmental factors.
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4.0 Methodology
4.1 Overview
4.1.1.1 Based on the current understanding of the project an analysis of site and route options, with an appraisal and identification of alternatives to these, was required.
4.1.1.2 The focus of this process is the offshore zone between the proposed landfalls identified in Scotland and England. The purpose of the process was to inform the selection of 500m wide corridor options within this zone that provide an optimal solution within environmental, engineering and economic parameters. The 500m corridors selected as part of this process will be subject to offshore marine routeing assessment.
4.1.1.3 The data collated and analysed as part of these processes will be at an appropriate level of detail for the stage of review being undertaken.
4.1.1.4 The Eastern HVDC Link has comprised the following phases of work to date:
Regional Review – a review of baseline data across an established Area of Search (AoS), to inform the selection of offshore routeing of the Eastern HVDC link. Baseline data collection, early consultation with key consultees, and landfall site visits sought to:
o Collate baseline environmental information in order to inform the design and routeing of the proposed works;
o Inform the assessment of environmental impacts; and
o Help identify constraints to the construction and operation of the offshore section of the Eastern HVDC link.
Corridor Review – to build on the regional reviews previously undertaken, and define specific project options to include:
o Landfalls (i.e. the transition between the terrestrial and marine environment);
o The selection of potential 10km wide offshore corridors between the landfalls at Peterhead in Scotland and Lackenby or Hawthorn Pit in England;
o Analysis of these potential offshore corridors, with a view to selecting ‘preferred options’; and
o The identification of 500m wide corridors inside the 10km wide preferred corridors and subsequent assessment of these.
4.1.1.5 It should be noted that the corridors identified in the Corridor Review Report have been selected based upon the level of detail commensurate with that stage of the development process (both in terms of scheme design and data collation).
4.1.1.6 Further consultation will be undertaken to assist in the final selection of a proposed subsea corridor, which will be subject to marine surveys. This will include statutory authority workshops, public exhibitions and the distribution of a consultation document.
4.1.1.7 Onshore Scotland and onshore England studies have been undertaken in parallel with the offshore work.
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4.2 Regional Review
4.2.1.1 The initial phase of works focussed on the collation of environmental baseline data within an established AoS to inform the selection of offshore routeing of the Eastern HVDC link.
4.2.1.2 The offshore regional review determined the major constraints and identified the opportunities relating to the construction and operation of the HVDC cable in the offshore, including the nearshore sections of the AoS.
4.2.1.3 Initial Stakeholder Engagement
4.2.1.4 Initial stakeholder consultation was carried out in March 2011 and involved informing key consultees of the project concept and inviting them to provide comments. In addition they were asked to raise any issues relating to the project, in order to facilitate a robust appraisal of potential issues, and to ensure that these could be identified and addressed early during the planning phases of the project. The key consultees consulted at this stage were:
Scottish Natural Heritage (SNH);
Joint Nature Conservation Committee (JNCC);
Marine Scotland Licensing Operations Team (MSLOT);
Marine Management Organisation (MMO);
Aberdeenshire Council;
Scottish Fishing Federation (SFF);
Northumberland Inshore Fisheries and Conservation Authority (NIFCA);
National Federation of Fishermen's Organisations (NFFO);
North Eastern Inshore Fisheries and Conservation Association (NEIFCA);
Scottish Environment Protection Agency (SEPA);
Historic Scotland;
Net Gain (North Sea Marine Conservation Zones Project);
Natural England;
English Heritage; and
Environment Agency.
4.2.1.5 Offshore Routeing Workshop
4.2.1.6 Offshore corridor options were discussed with key statutory authorities (MMO, JNCC, NIFCA, MSLOT, SNH, SFF) at an offshore routeing workshop held in Edinburgh on 18th October 2011. Natural England, NEIFCA, Net Gain, English Heritage, SEPA, EA, NFFO and Historic Scotland were invited but were unable to attend. An additional meeting was held by NGET with Natural England, JNCC and MMO on 17th January, 2012.
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4.2.1.7 Fisheries Liaison
4.2.1.8 An additional meeting with NFFO and SFF was held in York on 7th November 2011 where more detailed fishing concerns were discussed. Following this meeting arrangements have been made to engage with Fishing Industry Representatives via the NFFO and SFF to facilitate meaningful consultation with fishermen who operate along the cable route.
4.2.1.9 Landfall Site Visits
4.2.1.10 Site visits to Peterhead, Lackenby and Hawthorn Pit landfalls were undertaken to assess site suitability and to identify any further constraints.
4.2.1.11 A visit to the Peterhead Landfall Option Area site was undertaken on 20th of July 2011 in order to assist in the determination of its suitability, and to identify intertidal and near shore constraints. . An additional site visit was conducted in November 2011 to provide a further review of landfall suitability.
4.2.1.12 A site visit to Teesside was undertaken on 23rd and 24th August 2011 for similar purposes to those described in Section 4.2.1.11.
4.2.1.13 A site visit to Hawthorn Pit was undertaken on 3rd November 2011 for similar purposes to those Section 4.2.1.11.
4.3 Corridor Review
4.3.1.1 In common with other types of linear development, the effect that a cable may have on the environment largely depends on the route chosen. Consequently, careful route selection is of prime importance in either avoiding or minimising adverse environmental effects wherever possible.
4.3.1.2 The first stage in selecting a cable route is to determine the AoS based upon the proposed terrestrial start and finish points of the cable. The AoS covers all practical potential routes between these points; in this case, all practical routes between the combination of potential converter station locations in Scotland and England. Within the area of search a desktop analysis of published information is undertaken in order to identify any major environmental and engineering constraints.
4.3.1.3 Following this analysis the initial constraints information is charted and considered in order to identify 10km wide potential regional route corridors.
4.3.1.4 Based upon this, desk based data correspondence based consultations and a review of the corridor options have been undertaken (Section 6.0)
4.3.1.5 Using the approach and criteria detailed in Section 7.0, 500m wide corridors were identified within the 10km wide route corridors and were subsequently assessed.
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5.0 Regional Review
5.1 Introduction
5.1.1.1 Marine baseline data were collected during the initial stages of project design. Baseline data may be obtained through desktop analysis of publicly available information, through survey work (such as offshore environmental surveys, which tend to take place later in the design process) or through data procurement. These data then provide a baseline against which subsequent data can be compared in order to assess the potential positive or negative impacts of the project.
5.1.1.2 The marine baseline data collected for the Eastern HVDC Link project focused on the offshore areas between the proposed landfalls at Peterhead, and Lackenby (and Hawthorn Pit). The purpose of collating and reviewing the available data was to inform the selection of offshore cable routeing and landfall location.
5.1.1.3 The marine baseline data collection undertaken to date has been through desktop analysis. Using the data currently available the principal environmental and socio-economic constraints to the project have been characterised.
5.2 Data Collation
5.2.1.1 Baseline data on potential environmental constraints were collated for the AoS (Figure 6) from a range of publicly available sources listed in Appendix 1.
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Figure 6: Area of Search
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5.2.1.2 The main preferred cable routeing characteristics included the shortest route, the route with the greatest potential for burial, the route minimising any interference with other users of the sea and the route with the least environmental effect.
5.2.1.3 Using the above as guidance, data for the following features were collated:
Wind farms;
Oil and gas infrastructure;
Cables and pipelines;
Marine conservation;
Marine geology, oceanography and bathymetry;
Protected wrecks;
Fisheries and shipping;
Offshore disposal sites and other seabed obstructions;
Dredging;
Landfalls; and
Planning and legislation.
5.2.1.4 Using this data set as a base, additional data have been collated for the purposes of this study. The additional data have been primarily sourced from the following:
SeaZone data;
Correspondencebased consultations and requests for information;
Brown and May Marine fisheries consultants;
Anatec shipping consultants; and
Site visits to Peterhead, Lackenby and Hawthorn Pit landfalls.
5.2.1.5 A summary of relevant data obtained from correspondence-based consultations and requests for information is given in Appendix 2.
5.2.1.6 An overview map of known marine designated areas and physical constraints is presented as Figure 7.
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Figure 7: HVDC marine designated areas and physical constraints overview map
Data correct as of July 2011, some draft Marine Conservation Zone (MCZ) and MCZ Reference Areas have changed since production of this figure. Figure and data are from MCZ project interactive map (www.mczmapping.org), except for those noted below. Data sources quoted in MCZ project: *MEDIN Data Archive Centre including BGS, Admiralty Charts, OLEX, Seismic, Samples and Multibeam data. **MEDIN Data Archive Centre - UKHO Admiralty chart. Pipeline and cable locations from DECC UKCS offshore infrastructure, Kingfisher and Admiralty charts. Sediment wave field data from: Holmes R, et al. (2004). DTI SEA Area 5: Seabed and superficial geology and processes. British Geological Survey Report CR/04/064N.
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5.3 Near Shore Constraints and Landfalls
5.3.1.1 Regional onshore studies indicated that Peterhead in Scotland and either Hawthorn Pit or Lackenby in England are the preferred converter station locations.
5.3.1.2 Three possible landfall areas in Scotland were identified for further assessment, namely Sandford Bay, Cruden Bay and a third area immediately north of the mouth of the Ugie River, north of Peterhead (Figures 8, 9 and 10).
5.3.1.3 For the Lackenby site three possible landfall areas have been identified, namely Coatham Sands, Redcar Sands and Marske Sands (Figure 11). For the Hawthorn Pit site three landfall areas have been identified, namely Easington Colliery, Blast Beach (Noses Point) and Seaham Hall Beach (Figure 12).
5.3.1.4 It is considered that for the 10km offshore route corridor all of the above landfalls are practicable. The onshore routeing studies for Scotland and England have considered all the landfall areas named above. While these onshore reports describe the onshore constraints and site visits, only the near shore constraints in the vicinity of these landfalls are considered below.
5.3.1.5 Near to Peterhead the main fishing activities in the area are potting/whelking, scallop dredging and demersal stern trawling. For the English landfalls the density of fishing activity is higher. The main fishing activities close to Hawthorn Pit landfalls are potting/whelking and occasional trawling (all types). There is a slight increase in near shore fishing activity for the Lackenby landfalls where the main types of fishing activity are trawling (all types) and potting/whelking.
5.3.2 Peterhead
5.3.2.1 Landfall Option 1: Sandford Bay
5.3.2.2 The Sandford Bay landfall area is located within a relatively small enclosed bay, immediately north of the Peterhead Power Station. The bay is bordered to the south by cliffs, and to the north by a rocky foreshore. The power station outfalls are visible to the south of the bay and an outfall from a wastewater treatment plant is visible to the north. Near shore constraints mapped onto Admiralty charts are shown in Figure 8.
5.3.2.3 The 10m depth contour is located approximately 0.8km from the mean high water (MHW) at the mid-point of the bay. This distance decreases to 0.3km from the shore in the northern part of the bay, but extends to over 1km offshore to the south. In the south of the bay, a small islet known as ‘The Skerry’ is located at the end of the seaward extent of the 10m depth contour. The southern section of the bay appears to have a number of rock outcrops and raised portions of seafloor, which could potentially pose a threat to navigation.
5.3.2.4 The southern half of the bay falls within a designated special protection area (SPA) (Buchan Ness to Collieston Coast) consisting of a 15km stretch of cliff formed mainly of granite and quartzite. The sites’ designation is due to the importance of these cliffs and the area as a breeding ground for various seabird species. The northern sections of the Sandford Bay fall outside of the SPA and therefore routeing the cable through these sections means the SPA could be avoided. However, if the cable route was to avoid crossing the outfalls described below, it may need to cross the designated site.
5.3.2.5 The geology of the area is expected to be similar to that of the surrounding cliffs and onshore areas. Here the drift geology is till, a reddish brown sequence of plastic clays and sands with the inclusion of gravel and cobbles. Below this is found a flint and quartzite till,
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similar to that of the exposed cliffs to the south. The underlying bedrock is Ordovician to Devonian granite. It is considered that construction difficulties could be encountered with the laying of cable in areas where the superficial deposits are thin or absent and excavation of the bedrock is required. The bay is relatively sheltered and thus natural sediment movement may not be a large issue.
5.3.2.6 There are four existing outfall pipes in operation within the bay. On the north-western shore, two long outfall pipes run seaward in a south-easterly direction from a sewage works. The outfall pipes run for approximately 0.7km, and were installed by burial within an excavated rock trench, backfilled and armoured with graded stone. The outfalls terminate at a designated spoil ground, which covers a large area of the central part of the bay. It is understood that these outfalls now discharge tertiary treated sewage, and that this should limit the amount of material which is being added to the spoil ground.
5.3.2.7 On the south-western shore of the bay there are two outfall pipes associated with Peterhead Power Station. These outfall pipes are relatively small in size and appear to encroach only into the intertidal area. One of the outfalls from Peterhead Power Station discharges cooling water, which is of elevated temperature compared to the receiving environment and may require consideration in relation to HVDC cable performance. The discharge outfall may also have an impact on the movement of sediment in the area.
5.3.2.8 Other seabed features in the bay include the wreck of the Constant Star which lies exposed and adjacent to The Skerry islet in the south of the bay (Figure 8). The wreck is visible and therefore poses a low risk to navigation.
5.3.2.9 To the south of Sandford bay lies Boddam Harbour, a small fishing port. Navigational considerations for cable laying associated with this harbour would most likely be related to recreational and/or smaller inshore fishing vessels. Important fishing activity includes creel potters and salmon fishing, with greater activity likely during spring/early summer. No anchorage area or places of refuge exist within the vicinity of Sandford Bay.
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Figure 8: Sandford Bay near shore constraints
5.3.2.10 Landfall Option 2: Cruden Bay
5.3.2.11 Cruden Bay is a small bay situated between Ward Point to the north, and The Skares to the south. The bay is backed by sand dunes and lies above a sediment-filled valley that may once have been the mouth of the River Ythan before the last glaciation (Merrit and Leslie, 20097). The underlying bedrock is Ordovician to Devonian granite. It is considered that construction difficulties could be encountered with the laying of cable in areas where the superficial deposits are thin or absent and excavation of the bedrock is required. Near shore constraints mapped onto an Admiralty chart are shown in Figure 9.
5.3.2.12 The bay is relatively shallow, with the 10m contour extending to approximately 1.5km from MHW at the mid-point of the bay. This depth contour decreases in distance from the shore to the north and south. The Skares is a granitic rocky reef outcrop located approximately 1km to the south-south-east of the southern end of the bay. Due to the nature of these shallow areas and rocky outcrops, this area may pose a hazard to navigation. Other areas of known fouling have been highlighted in Figure 9.
5.3.2.13 Additionally, there are numerous wrecks located within the bay. The wrecks are mainly concentrated around areas of shallow water, and in the vicinity of the Skares. Figure 9 highlights three known wrecks around The Skares. Records do show other wrecks in the area but these may be much smaller, or do not pose a hazard to navigation. None of the wrecks at this site are protected wrecks.
7 Jon Merritt and Graham Leslie. 2009. Northeast Scotland. A landscape fashioned by geology. British Geological Survey.
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Figure 9: Cruden Bay near shore constraints
5.3.2.14 The whole of Cruden Bay, and the surrounding area, is enclosed by the Buchan Ness to Collieston Coast SPA, yherefore routeing the cable through the SPA is unavoidable for this landfall option. Notable observations of sperm whale and harbour porpoise have occurred within the bay.
5.3.2.15 The Buchan Ness to Collieston Coast special area of conservation (SAC) extends to the north and south of Cruden Bay, but does not encompass the bay itself. It is designated due to vegetated sea cliffs.
5.3.2.16 To the south of the bay, a number of pipelines associated with the Forties oilfield, and the Central North Sea cable, make landfall. The pipelines are operated by BP and have been established since the 1970’s.
5.3.2.17 Located within the bay is a recommended anchoring area, with no defined limits. The anchoring area is located in a fairly central position within the bay. Risks associated with anchor strikes could be negated by burying the cable at depth, mechanical protection or avoiding this area.
5.3.2.18 Cruden Bay harbour is located on the northern shore of the bay. Navigational considerations associated with this harbour would most likely be related to recreational and/or smaller inshore fishing vessels.
5.3.2.19 Landfall Option 3: Bay North of Peterhead (between Craig Ewan and Kirkton Head)
5.3.2.20 The landfall site is located on a long stretch of beach north of Peterhead, bordered to the south by Craig Ewan and to the north by Kirkton Head. The bay consists of fine sands along
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its entire length until meeting rocky outcrops at the northern and southern borders of the bay. The beach has a gradual slope, which becomes large sand dunes in land.
5.3.2.21 Kirkton Head is fronted by a drying rocky ridge which extends up to 0.8km seaward. Craig Ewan, a rocky projecting point, is located 1.6km south of Kirkton Head.
5.3.2.22 The bay is relatively shallow, with the 10m contour extending to approximately 1.5km from the shore (HWM) at the mid-point of the bay.
5.3.2.23 In the bay directly to the south of Craig Ewan are two disused submarine cables, extending from shore in a north-easterly direction, for approximately 1.6km (Figure 10). Approximately 4km offshore from the southern end of the bay lies the northern boundary of a spoil ground, approximately 2km by 2km in size.
5.3.2.24 There are no wrecks in the immediate vicinity of the bay, although there are several named and unnamed wrecks located greater than 4km due east of the bay. None of the wrecks are protected wrecks.
5.3.2.25 To the south of the bay, at the mouth of the River Ugie lies Buchanhaven, a small fishing village with a small boat harbour among the rocks. Navigational considerations associated with this harbour are most likely to be related to recreational and/or smaller inshore fishing vessels.
Figure 10: Bay north of Peterhead near shore constraints
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5.3.2.26 Future Projects
5.3.2.27 There are several potential future projects in the Peterhead area that may be impacted upon, or impact on, landfall options for the Eastern HVDC Link and associated infrastructure.
5.3.2.28 NorthConnect Interconnector
5.3.2.29 A consideration (specifically at Sandford Bay) may be the proposed NorthConnect Interconnector. This interconnecter cable, proposed by Vattenfall, E-CO Energi, Agder Energi, Lyse and SSE Interconnector Ltd, may represent the first interconnector between Norway and the UK. The NorthConnect project is currently in its early stages of development with the aim of having the cable in operation by 2020. To date, an outline scope of works for the purposes of landfall section of the cable has been defined, and a grid application made at Peterhead.
5.3.2.30 Peterhead Carbon Capture and Storage (CCS)
5.3.2.31 The Peterhead CCS project relates to the construction of a combined cycle gas turbine power plant with an installed capacity of 550 MW, generating nominally 475 MW of low carbon electricity. The proposed area for the plant lies to the north of the existing Peterhead Power Station. The project will combine separate technologies – hydrogen production, power generation and carbon capture and storage for enhanced oil recovery (EOR).
Carbon dioxide (CO2) produced will be processed and transported, by an existing pipeline, to the St Fergus gas terminal. From here the CO2 will then be transported via another existing pipeline to the Miller platform in the North Sea and injected into the mature Miller oil field reservoir, to facilitate EOR.
5.3.2.32 Statoil Hywind
5.3.2.33 The Statoil Hywind project represents the world’s first full-scale floating wind turbine. The floating structures extend 100 metres beneath the sea’s surface and are attached to the seabed by a three-point mooring spread. The turbine is designed for use in offshore locations deeper than turbines typically operate in, and the technology is currently being tested 10km off the coast of south-west Norway. Statoil are currently assessing locations for future pilot parks at locations off the UK coast. An area off Aberdeenshire is being assessed as a candidate for a pilot park of three to five turbines.
5.3.2.34 Statoil have recently been contacted regarding the Hywind project as part of the HVDC consultation exercise. No response has been received at the time of writing, however should any pertinent information arise it will be considered in subsequent assessment.
5.3.3 Lackenby
5.3.3.1 Near shore constraints mapped onto Admiralty charts are shown in Figure 11. The three potential landfall zones at Coatham Sands, Redcar Sands and Marske Sands are also marked in Figure 11. All landfalls will lie within the 10km corridor, and as such will not affect the determination of offshore corridor options. Potential landfall areas are described below.
5.3.3.2 Landfall Option 1: Coatham Sands
5.3.3.3 Coatham Sands shelves shallowly seaward, as indicated by the broad expanse of the intertidal zone. The 10m depth contour is located just under 1.9km from MHW for much of Coatham Sands. The embayment that is formed at Coatham Sands is bounded by the
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South Gare Breakwater (adjoining the River Tees estuary and port to the west) in the north west, and to the south-east by West Scar rocks and the Salt Scar.
5.3.3.4 The rocks at the southeastern limits of the beach essentially constrain the potential cable corridors’ approach to the landfall. The rocks are marked by sector navigation lights on the shore and a north cardinal buoy for vessels to pass at a safe distance from the Salt Scar.
5.3.3.5 The South Gare breakwater at the southern entrance to the Tees estuary is marked by a lighthouse, and the Tees fairway (dredged channel) is marked by a buoy approximately 4.5km to the north-east of the end of the South Gare breakwater. The channel is maintained by dredging to a minimum depth of 15.4m.
Figure 11: Lackenby near shore constraints
5.3.3.6 There are a number of wrecks marked on the chart lying off Coatham Sands. Two are present at the north-west of the study area in the lower intertidal, while there are a number of wrecks in the shallow subtidal particularly in the waters in the vicinity of the South Gare breakwater and around the West Scar and Salt Scar rocks.
5.3.3.7 There are a number of both inter and subtidal discharge pipelines. The location of one of the intertidal outfalls was recorded during the intertidal site visit. Two outfalls that extend across the West Scar rocks are marked at their seaward extents by markers.
5.3.3.8 Figure 11 shows the CATS (Everest) offshore gas export pipeline coming ashore at the south-eastern end of the beach. In addition the Teesside Offshore Wind Farm, which has been consented, but is yet to be constructed will occupy the majority of the near shore waters between the Tees Fairway and the CATS gas pipeline corridor, out to a distance of
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approximately 3.7km offshore. These two offshore developments provide the largest constraint to a potential cable landfall at Coatham, which will require it to be laid into a very narrow corridor between the two constraints.
5.3.3.9 The Admiralty chart shows a seabed sediment type in around 12m of water as being of sand and shells. It is anticipated that the sediment type is similar in the immediate near shore area.
5.3.3.10 The landfall area and its near shore waters are contained within the limits of the Tees and Hartlepool Port Authority, which extends as far to the south-west as the West Scar rocks. The intertidal areas as far as the Salt Scar rocks are included within the South Gare and Coatham Sands Site of Special Scientific Interest, which is also a constituent part of the Teesmouth Flats and Marshes SPA/Ramsar complex.
5.3.3.11 The near shore waters are a recommended anchorage for commercial shipping awaiting entry into the Tees Estuary. At the time of the field visit a number of vessels were observed at anchor offshore from the beach at Coatham Sands. PD Ports advised that numerous vessels anchor in between the CATS (Everest) gas and NORPIPE (Ekofisk) oil pipelines (Figure 11). Anchoring is prohibited within 6 cables (1.1km) of the Tees Fairway light-buoy, in the Tees Approach Channel and within 2.5 cables (0.5km) of the pipelines.
5.3.3.12 Slightly further offshore there are a number of spoil grounds. It is understood that these areas are used to deposit dredged tailings from the Tees estuary. The main Tees channel is dredged on a continuous basis.
5.3.3.13 Landfall Option 2: Redcar Sands
5.3.3.14 The beach at Redcar Sands has a similar gradient to Coatham Sands. At low water the intertidal area is a wide and flat expanse of sand, and this continues subtidally out to the 10m isobath which occurs approximately 1.9km from MHW. The beach is situated between the towns of Redcar and Marske-by-the-Sea. The shoreline at this landfall option is characterised by a degree of erosion. Despite the wide expanse of intertidal sands, the low earth cliffs at the top of the supratidal zone are being eroded.
5.3.3.15 At the north-west extent of the shore the town of Redcar is protected by concrete sea defences and groynes which maintain the littoral sediment. The seafront flood defences are currently being extended southwards down the coast. This work is being funded and managed by the Environment Agency. It will include a new wall which will stretch for 2.7km from Coatham to the eastern end of the Stray, an open public strip of coastal grassland situated between the beach and the A1085. The works will also include repairs to the existing groynes. There is gap of approximately 500m between the southernmost groyne and the landfall of the existing cables. It is in this gap where the HVDC cable could be brought ashore. As the new works will not extend further than the southernmost groyne, there would be no requirement to cross these, should this landfall be selected. The new sea defence works are due to be completed in Spring 2013.
5.3.3.16 The Admiralty chart shows the seabed sediment in around 4m of water as being dominated by sand. It is anticipated that the sediment type is similar in the immediate near shore area.
5.3.3.17 In the near shore waters lying off the beach a bathymetric feature exists; this is marked on the Admiralty chart as ‘The High’. This isolated, slightly raised area of seabed is approximately 2m shallower than the surrounding seabed.
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5.3.3.18 Immediate navigational constraints include the Salt Scar north cardinal buoy that is located around 3.7km north of the beach, and a continuation of the commercial vessel anchorage for vessels entering the Tees estuary.
5.3.3.19 At Marske-by-the-Sea a small indentation in the coast where a river discharges allows some sheltered beach storage for a number of small fishing vessels. Boat launching from this location would be across the beach, as no tidal channel exists to link this area with the sea. During the site visit, some small craft were observed in the near shore waters, as well as some sea-kayakers, which were believed to have launched from Saltburn.
5.3.3.20 A number of cables are brought ashore at the beach. At least one of these is a telecommunication cable. All three cables traverse the near shore waters at the proposed landfall area at an angle of approximately east-north-east. The cables would present a constraint to the cable approach through the near shore waters, though cable crossings are possible. The cable would be restricted to an approach aligned with the gaps between the existing cables.
5.3.3.21 There are a number of wrecks in the near shore waters at this landfall option. Several are located to the north of the beach, in and around the Salt Scar and West Scar rocks, and a number of others are located slightly further offshore from the rocks in around 10-20m water depth. No wrecks lie on a direct approach perpendicular to the shore, and as such the wrecks described should present no threat to construction.
5.3.3.22 During the field visit an outfall that extended into the intertidal area was observed, as well as a number of smaller discharges at the top of the shore. The Admiralty chart shows a longer sea outfall that extends offshore from the beach for approximately 1.5km. This outfall discharges in approximately 5m of water.
5.3.3.23 Landfall Option 3: Marske Sands
5.3.3.24 Figure 11 indicates many of the constraints in the near shore waters apply to both Redcar Sands and Marske Sands.
5.3.3.25 The near shore waters at Marske shelve with a relatively shallow gradient, which is similar to the two landfall options to the north. The wide expanse of intertidal sands are continued subtidally, with the seabed sediment offshore being recorded on the Admiralty chart as sand in approximately 15m water depth. Rocky areas exist to the south-east of the area at Saltburn Scar. This area is characterised by high hard rock cliffs, which extend offshore. This rocky area is the other side of Saltburn however.
5.3.3.26 The coastal cliffs between Marske (taken to include Marske-by-the-Sea and New Marske) and Saltburn are being eroded, similar to that between Redcar and Marske. The cliffs in the vicinity of landfall Option 3 however are considerably higher, and the seaward faces of the cliffs are vegetated. In some areas along the cliff bases young dune systems are developing, suggesting that the rate of erosion along this stretch of coastline is not as rapid as at landfall Option 2.
5.3.3.27 Due to the proximity of this landfall option to the seaside resort of Saltburn, the area was considerably busier with people in the near shore waters immediately off the beach. Bathers, surfers and sea-kayakers were observed during the field visit.
5.3.3.28 To the north, the telecommunications cables described for Landfall Option 2 extend in a north-east to south-west direction perpendicular to the coast. All of these cables make landfall to the north-west of Marske.
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5.3.3.29 The pier at Saltburn extends into the intertidal zone. Further north along the shore, a large outfall extends below the HW mark, observed during the field visit. This structure was protected with heavy rock armour.
5.3.3.30 Some wrecks can be observed in the near shore waters, more than 3.5km offshore in water deeper than approximately 20m. The wrecks are situated to the south-west of the landfall beach off Hunt Cliff.
5.3.4 Hawthorn Pit
5.3.4.1 Near shore constraints in the area close to Hawthorn Pit have been mapped onto Admiralty Charts (Figure 12). Three possible landfall areas identified during the desktop study have been marked on Figure 12, and near shore constraints for these options are discussed below.
5.3.4.2 Landfall Option 1: Easington Colliery
5.3.4.3 The near shore waters at this landfall are characterised by an exposed stretch of coastline backed by cliffs of approximately 50m in height. The intertidal area is comprised of sand and cobbles with rock scar, and this continues subtidally. As far as the 5m isobath there are numerous rocks and obstructions, possibly remnants from coal workings. The numerous rocks and obstructions in the near shore waters are charted, and present a recognised danger to navigation close to the coast, however the water depths over these have not been charted.
5.3.4.4 The seabed is moderately sloping. Approximately 1.2km from MHW the 10m isobath is reached, while the 50m isobath is approximately 15-16km offshore.
5.3.4.5 The landfall forms a break in the Durham Coast SAC (primarily designated because of vegetated sea cliff communities). The break in the SAC is as a consequence of the colliery workings that previously occupied the site. The colliery has been demolished and the site landscaped over and partly remediated as part of the “Turning the Tide” project. This project also involved the cleaning of the beaches in the vicinity of the colliery. The Admiralty Chart and historic mapping show that a colliery waste conveyor used to dump slag material into the near shore waters, as such some material is likely to still be present.
5.3.4.6 To the south of the landfall at Horden Point an outfall extends as far as the 10m isobath. It is possible that this outfall is associated with the former Horden Colliery.
5.3.4.7 Seabed sediments are described as fine sand, mud and shell at water depths of around 15m.
5.3.4.8 Landfall Option 2: Blast Beach (Noses Point)
5.3.4.9 This landfall is just to the south of the town of Seaham and has a similar seabed topography to that found at Easington Colliery. The 10m isobath is approximately 1km from MHW. The near shore waters are also characterised by rocks or obstructions, which are charted, but the water depths are unknown. An outfall extends out as far as the 15m isobath and the obstruction at the seaward end is marked by a buoy (this is likely to be a treated sewage discharge pipe).
5.3.4.10 Due east of the proposed landfall in around 10-15m water depth a spoil ground is shown on Figure 12.
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5.3.4.11 The seabed sediments in the near shore waters are described as pebbles, gravels, sand / broken shell and rock at around 15-20m water depth.
5.3.4.12 As with Easington Colliery, this landfall is also the site of a former colliery (Dawdon), and has been landscaped and remediated, however waste coal and slag material was previously dumped onto the beach and near shore areas.
5.3.4.13 Landfall Option 3: Seaham Hall Beach
5.3.4.14 The shoreline is relatively steeply shelving, and the 10m isobath is approximately 1km from MHW. The seabed sediments are described as a mixture of rock and shingle, while further to seaward are comprised fine sand, pebbles, gravel, broken shell and rock.
5.3.4.15 In the immediate near shore waters there are numerous rocks, both exposed at low water and those below the surface, where the water depth over them is unknown.
5.3.4.16 To the south and north of the landfall there are rock scar grounds intertidally that extend subtidally (Pincushion and Featherbed Rocks respectively). These are wave-cut bedrock shelves, rather than boulder scar.
5.3.4.17 To the south and south-east is the port of Seaham and its designated commercial vessel anchoring area.
5.3.4.18 Within 2km to the north of the Seaham Hall Beach landfall is the southernmost extent of the Sunderland Port Authority jurisdictional limits.
Figure 12: Hawthorn Pit near shore constraints
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6.0 Route Corridor Options (10km wide corridors)
6.1 Introduction
6.1.1.1 In considering potential offshore cable routes, various constraints apply including existing environmental conditions and potential for related impacts, together with engineering issues.
6.1.1.2 The key constraints related to the construction and operation of the HVDC cable considered to be important at this stage, and to be avoided where possible, include the following:
6.1.1.3 Physical:
Difficult areas for construction such as severe slopes, exposed bedrock, areas of mobile seabed, sand banks, sand waves and mega-ripples, shallow gas in sediments (pockmarks), etc.;
Shallows and subtidal sand banks; and
Rocky and/or steep landfalls.
6.1.1.4 Human:
Safety zones around infrastructure (e.g. offshore wind farms, oil and gas wells and platforms);
Archaeological features, including ship wrecks;
Areas of high fishing intensity;
Areas of high shipping intensity;
Shipping separation, traffic, and anchoring zones;
Pipeline and cable crossings;
Military practice and exercise areas (PEXA);
Active, licensed or proposed dredge areas; and
Dump sites for dredged sediments, munitions and other material.
6.1.1.5 Biological:
Environmentally protected and sensitive areas.
6.1.1.6 In addition, the following were important factors:
Shortest route length to be maintained (to ensure most economic options considered); and
Consideration wherever practicable of the concerns of potentially affected parties.
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6.2 Constraints and Option Summary
6.2.1.1 The major constraints relating to the construction and operation of the offshore section of the HVDC cable are presented as Table 1 below. These constraints can be divided into 1) ‘no go’ areas (areas where the cable cannot go, or areas in which it will be very difficult to install the cable), 2) areas where the cable can be placed but will be subject to negotiation, and 3) areas that need further surveying to determine suitability, or that can be routed around.
Table 1: Major constraints summary
Areas requiring detailed surveying/detailed routeing Marine Conservation Zone Pipeline/cable crossings Wrecks Reference Areas Marine environmental high Disposal areas (spoil grounds) Areas of mobile sediment risk areas (MEHRAs) Designated anchorage Environmentally sensitive and Areas of exposed bedrock and zones protected areas (eg. SPA, SAC) other hard ground Dredged channels Marine Conservation Zones Other geological constraints Protected wrecks Important fishing grounds PEXA Wind farm development blocks and associated cable routes and connections Important areas for navigation
6.2.1.2 Four, 10km wide route corridor options (A to D) were identified (Figure 13) and these were considered against known constraints.
6.3 Corridor Options
6.3.1.1 The shortest distance between any two points is a straight line and this is the starting point for determining route corridor options. However a straight line running between Peterhead and Lackenby/Hawthorn Pit converter stations crosses several major constraints, namely:
The Buchan Ness to Collieston Coast SPA;
Four pipelines (Cruden Bay – Forties x2 (All landfalls), NORPIPE and CATS pipelines (Teesside landfalls only));
One cable (CNS cable);
The proposed Norway interconnector (connecting at Blyth);
The Firth of Forth Offshore Wind Farm;
NG14 recommended Marine Conservation Zone (MCZ) Farnes East;
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RA12 recommended MCZ Reference Area (situated inside MCZ NG14);
Teesside Offshore Wind Farm (Teesside landfalls only);
Marine disposal and dumping/spoil grounds;
Areas of potential rock outcrop / lower burial potential;
Areas of sediment wave fields, and
Fishing activity and spawning grounds.
6.3.1.2 It may be possible to route the cable through some of these constraints, although some will need to be avoided (Table 1).
6.3.1.3 All potential landfalls that have been identified at both Peterhead and Lackenby/Hawthorn Pit (see Section 5.3) are incorporated in the route corridors.
6.3.1.4 The four route corridor options proposed were determined by starting with a straight line route and then adjusting to avoid constraints. All routes avoid the ‘no go areas’, with options being devised by either routeing through or around other, ‘softer’ constraints. Corridors A, B and C have a landfall option for Hawthorn Pit. Corridor D only includes landfalls for Lackenby.
6.3.2 Corridor Descriptions
6.3.2.1 Route corridors are presented in Figure 13. This section provides a brief description of each corridor. The offshore aspects and constraints for each corridor are described in Section 6.3.3 to Section 6.3.5 Where distances are quoted they are taken as the centreline in the corridor.
6.3.2.2 Corridor A
6.3.2.3 This route passes to the seaward side of the Firth of Forth Offshore Wind Farm, and between recommended MCZ NG14 and NG15. It avoids rocky areas near to the northern end of MCZ 14, and in the southern section is routed through seabed sediments consisting of muddy sand. The route is wider than 10km at its southern section. This is to ensure that options are available when more detailed routeing is undertaken, to incorporate the more favourable geology in the area and have options to route in-between or around the outside of the spoil grounds.
6.3.2.4 Corridor B
6.3.2.5 This route is the straightest, and thus shortest, route option. The corridor passes through some of the Phase 3 area of the Firth of Forth Offshore Wind Farm. Additionally it passes through MCZ NG14, but avoids the reference area RA12 in MCZ NG14. This section also passes large areas of potential rock in MCZ NG14 (the presence of which would be confirmed by the geophysical survey, and avoided in routeing if this corridor was selected).
6.3.2.6 Corridor C
6.3.2.7 The corridor passes to the west of the Firth of Forth, Inch Cape and Nearth na Goith Offshore Wind Farms. Part of the cable corridor lies within MCZ NG14. This route, although longer that the other options, has been included in the study in order to make sure that all potential, feasible routes are investigated.
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6.3.2.8 Corridor D
6.3.2.9 This route is essentially the same as Corridor A, but deviates from it in the southern section of the route. There are two options for Corridor D – one avoiding all of the areas of highest intensity fishing in the south (D2) and one avoiding only the highest intensity fishing areas just to the north of the mouth of the Tees (D1) (Figure 13).
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Figure 13: HVDC 10km wide corridors
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6.3.3 ‘No Go’ Areas
6.3.3.1 The following areas are those that the HVDC cable will be required to avoid, due to third party requirements or due to those areas being unfeasible for cable routeing. As the corridors are 10km wide there is some overlap with a number of ‘no go’ areas, which may be resolved when a preferred route is selected.
6.3.3.2 Marine Conservation Zones Reference Areas
6.3.3.3 All the corridors are routed around the reference areas in MCZ14 and MCZ15 (RA12 and RA13) Corridors B and C pass to the western side of reference area RA12, and corridors A and D pass between the two MCZs (Figure 14).
6.3.3.4 MEHRAS
6.3.3.5 Marine environmental high risk areas (MEHRAs) are 32 small areas around the UK coast identified and classified due to their combined high shipping risk and high environmental sensitivity8. The majority are located within sites already designated for environmental reasons. It is logical to conclude that these are areas which should be avoided by the cable route. Due to their small size, and location close to the coastline they are not difficult to avoid.
6.3.3.6 The Tees Holy Island MEHRA is situated just inside Corridors B and C and just outside Corridors A and D (Figure 15). However, as the MEHRA is situated at the edge of the 10km corridors it can be avoided when the preferred route is established. Corridor C passes close to, but is does not cross, several other MEHRAs, the closest of which is the Isle of May.
6.3.3.7 Designated Anchorage Zones
6.3.3.8 There is an anchoring area in Cruden Bay (Section 5.3.2.10), which all corridors pass thorough, if this landfall zone is selected. Although this anchorage has no defined limits it can be avoided when the preferred route is established as is likely to be small and related to recreational and/or smaller inshore fishing vessels. There are also numerous cables and pipelines already in the bay, to the north of the anchorage marked in the Admiralty chart.
6.3.3.9 Corridor C passes approximately 3.5km from the designated anchorage at Aberdeen. Vessels, especially larger ships, often anchor outside of the eastern limit of the anchorage area and thus would be inside the corridor.
6.3.3.10 All corridors which landfall to the south of the Tees pass through the areas designated for anchorage in the Tees estuary (Section 5.3.3). Information on the defined limits of the anchorage (or, if the limits are undefined, typical anchoring positions of vessels) will be required when the route corridor is refined in order to avoid this anchorage.
6.3.3.11 Dredged Channels
6.3.3.12 The Tees channel is continuously dredged to a depth of 15.4m and all corridors which landfall to the south of the Tees, intersect the dredged area. This area could easily be avoided when the preferred route is identified.
6.3.3.13 Protected Wrecks
8 Establishment of Marine Environmental High Risk Areas (MEHRAs), Department for Environment, Food and Rural Affairs, 2006. Available online: http://webarchive.nationalarchives.gov.uk/+/http://www.dft.gov.uk/pgr/shippingports/shipping/elc/ secmehras/
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6.3.3.14 All corridors pass close to the protected wreck at Seaton Carew, Hartlepool (Figure 15). However it does not lie within any of the corridors, nor are there any other protected wrecks within 50km of the corridors.
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Figure 14: Conservation areas in the study area
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Figure 15: Lackenby constraints and corridors
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6.3.4 Areas Subject to Negotiation
6.3.4.1 The following constraints can be crossed by the cable routes, but negotiation with relevant parties will be required.
6.3.4.2 Cable and Pipeline Crossings
6.3.4.3 All corridors will cross the following cables and pipelines:
Forties C to Cruden Bay PL8 pipeline;
Forties C to Cruden Bay PL721 pipeline;
CNS FIBRE OPTIC Cable (BP); and
NORPIPE (Ekofisk) oil pipeline.
6.3.4.4 Depending on the landfall selected in England, the HVDC cable may also cross:
CATS (Everest) gas pipeline;
CANTAT 3 F4 (BT) cable; and
PANGEA NORTH UK/DNK cable.
6.3.4.5 Additionally export cables are proposed connecting Inch Cape, Neart na Gaoithe and the Firth of Forth offshore wind farms to shore. As Corridor C is landward of these wind farms, a route within that corridor it would have to cross these 4 cables (2 proposed from the Firth of Forth). Other cables from the proposed Dogger Bank offshore wind farms may also be routed into the Teesside area. The alignment of the HVDC cable will be considered as more information becomes available on such export cables.
6.3.4.6 The proposed NorthConnect interconnector (Section 5.3.2.28) proposed to landfall at Peterhead, will also have to be considered and may have to be crossed depending on the relative timings of the projects.
6.3.4.7 Crossings of cables and pipelines will require a crossing agreement between parties which own existing facilities on the seabed and National Grid/SHETL.
6.3.4.8 Disposal Areas (Spoil Grounds)
6.3.4.9 The HVDC route would ideally avoid disposal areas, however routeing through these areas may be feasible.
6.3.4.10 Sandford Bay spoil ground is located close to the Sandford Bay landfall (Section 5.3.2.6, Figure 8) at the seaward end of two sewage outfall pipes. Sewage discharged through these pipes has been treated to a tertiary stage, and thus the spoil ground should not pose an issue to pipeline routeing with respect to any discharge material.
6.3.4.11 A small spoil ground located in Aberdeen harbour is inside Corridor C, but it would be possible to avoid it in detailed routeing.
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6.3.4.12 Two spoil grounds are located close to Newcastle Upon Tyne. Corridor B partially intersects both of these, and Corridor C partially intersects the smaller, more southerly of the two (Figure 16).
6.3.4.13 There are two spoil grounds situated in or near to the Tees Bay that all of the corridors with landfalls to the south of the Tees intersect (Figure 15). The most northerly of these is disused and the other is the Inner Tees Bay A ground, which is used for disposal of dredgings from the Tees Estuary. There is a third disposal area that corridors A, B and C intersect. All of the disposal areas are all small enough to be avoided when the preferred route is defined, however careful routeing in this area will be required.
6.3.4.14 Environmentally Sensitive and Protected Areas (e.g. SPA, SAC)
6.3.4.15 For the Cruden Bay landfall, all routes would pass through the Buchan Ness to Colllieston Coast SPA, which forms a coastal strip 3 to 4km wide. The northern extent of this SPA lies approximately half way across Sandford Bay, and therefore (should this landfall be selected) it is also possible that routes would pass through the SPA (Figure 17). The Buchan Ness to Collieston Coast SAC extends to the north and south of Cruden Bay, but does not encompass the bay itself. Vegetated sea cliffs are the reason for its designation.
6.3.4.16 All corridors for landfalls south of the Tees pass through part of the South Gare and Coatham Sands Site of Special Scientific Interest, which is also a constituent part of the Teesmouth Flats and Marshes SPA/Ramsar complex (Section 5.3.3.2). However the actual HVDC cable route would only pass through this site if the Coatham Sands landfall were to be selected.
6.3.4.17 Sections of the Northumbria Coast SPA are intersected by the corridors with landfalls for Hawthorn Pit. This SPA is characterised by mainly discrete sections of rocky shore with associated boulder and cobble beaches and a small section of sandy beach. The site qualifies as an SPA as it supports populations of European importance of little tern in breeding season and over-wintering populations of purple sandpiper and turnstone. The SPA is also coincident with a Ramsar site
6.3.4.18 The Durham Coast SAC extends intermittently along the coast close to Hawthorn Pit, and is designated due to the presence of vegetated sea cliffs. Any 10km corridors making landfall for Hawthorn Pit cross this SAC, but due to its intermittent nature the final cable route may not necessarily have to pass through it.
6.3.4.19 No further SACs (designated, candidate or possible) are crossed by any of the other corridors.
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Figure 16: Spoil grounds in the study area
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Figure 17: Peterhead landfall options and constraints
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6.3.4.20 Marine Conservation Zones
6.3.4.21 Corridors B and C pass through MCZ NG14 for 41km and 34km respectively (Figure 14). The corridors do not pass through any other MCZs.
6.3.4.22 It may be possible for sections of the cable route to be routed through MCZs as guidance from the “Net Gain” Science Advisory Panel states that with respect to new developments - “from a scientific viewpoint, co-location can only be considered on a site by site basis and the conservation objectives and the particular activities are the material issue”. Defra Guidance on the duties of public authorities in relation to Marine Conservation Zones (Note 2) states that the Marine and Coastal Act 2009 requires them to consider the effect of proposed activities on MCZs before authorising them, and imposes restrictions on the authorisation of activities that may have a significant risk of hindering the conservation objectives of an MCZ.
6.3.4.23 The conservation objectives of MCZ NG14 are to maintain (subject to natural change) the following habitats in favourable condition:
Moderate energy circalittoral rock;
Subtidal coarse sediment;
Subtidal sand;
Subtidal mixed sediments; and
Peat and clay.
6.3.4.24 In addition, the conservation objectives of MCZ NG14 are to recover (subject to natural change) subtidal mud to favourable condition by 2020 and maintain thereafter. Of these habitats only peat and clay is classified as a habitat of conservation importance, and this lies almost solely within the reference area RA12. The others are classified as broad scale habitats.
6.3.4.25 Net Gain’s final recommendations, which have recently been submitted to Natural England and the JNCC, state that “human activities which cause pressures [on the habitats] will need to be managed if they prevent the conservation objectives from being achieved”. Therefore, although co-location of the cable and MCZ NG14 may be possible, it will be subject to discussion with the relevant authorities (JNCC and Natural England).
6.3.4.26 However, it should be noted that the MCZ reference areas (RA12 and RA13) (Figure 14) need to be avoided. The JNCC guidance document for regional MCZ projects states that some activities are incompatible with reference areas, and such activities include construction of structures, dredging and deposition of gravel/rock. It also states that there should be no new cables once a reference area is in place.
6.3.4.27 Therefore the cable route should avoid any MCZ reference zones and ideally any MCZs. However some co-location of the route and MCZ NG14 (i.e. Corridors B and C) could potentially shorten the route length by several kilometres.
6.3.4.28 Scottish Marine Protected Areas
6.3.4.29 The Marine (Scotland) Act and the UK Marine and Coastal Access Act contain new powers for Scotland to designate a network of Marine Protected Areas (MPAs) within their offshore
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waters. MPAs can be designated in Scottish territorial waters (inside 12 nautical miles) for the following purposes:
Nature conservation MPAs: for the conservation of nationally important marine wildlife, habitats, geology and undersea landforms;
Demonstration/research MPAs: to demonstrate or research sustainable methods of marine management or exploitation; and
Historic MPAs: for features of historic/cultural importance such as shipwrecks and submerged landscapes.
6.3.4.30 The UK Marine and Coastal Access Act 2009 includes equivalent provisions for Scotland to designate MPAs for the conservation of nationally important marine areas in Scottish offshore waters (outside 12 nautical miles). Although legally MCZs, they will collectively be referred to as Nature Conservation MPAs, and will be established using the same MCZ site selection guidelines as used in England and Wales. Nature Conservation MPAs will contribute toward the UK’s commitments of ecologically coherent networks of well-managed MPAs in the North East Atlantic.
6.3.4.31 In terms of timescales, Marine Scotland intends to finalise the identification of an MPA network by 2012, and to deliver a network of sites by 2016. A series of workshops with marine stakeholders have been held throughout 2011, with the third and final MPA stakeholder workshop being held at the end of the end of October 2011.
6.3.4.32 At the current time Scottish MPAs are not considered a direct constraint to the HVDC corridor routeing, as they are not due to be established until 2016. However the progress of the Scottish MPA process will be monitored.
6.3.4.33 Fisheries
6.3.4.34 Most of the commercial fishing effort and highest landing value areas are located in the near shore areas, with the majority of smaller fishing vessels (<10m in length) recorded in this area. Data considered in Figure 18 include all UK and non-UK vessels landing into UK ports.
6.3.4.35 The highest levels of fishing were recorded along the coast between Berwick-upon-Tweed and Teesside (Figure 18). The type of fishing carried out in this region is mainly potting and trawling. There were a significant number of vessels fishing in the section of Corridor C that runs along the coast of Scotland. These were mainly potters/whelkers and scallop dredgers, but there were also some demersal trawlers in operation in this area.
6.3.4.36 Significant fishing activity in the Peterhead/Boddam area has also been reviewed. Important fishing activity includes creel potters and salmon fishing.
6.3.4.37 Corridor C is therefore the least preferred in terms of fisheries. Corridors A and B are similar in terms of the numbers of vessels recorded, however Corridor A appears to support slightly less fishing activity, being further offshore.
6.3.4.38 Corridor D is optimal from a fisheries perspective as it avoids areas of greatest fishing intensity near to south Tees (Figure 18). However, it could potentially have a disproportionate impact upon creelers / potters whose activities take place on rocky seabed where rock armouring is likely to be required.
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Figure 18: Fishing activity in the study area
.
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6.3.4.39 Spawning Grounds
6.3.4.40 There are several fish species whose spawning areas fall within the cable corridors, some of which spawn throughout the whole length of the corridor and beyond. Because of the wide area over which spawning takes place, and the relatively low impacts generated by installation and operation of the cable (physically low impact from installation, and narrow footprint), spawning areas have not been presented as a constraint. Many fish species spawn in the water column rather than on the seabed, those that need to be considered in detail are herring and sand eels, both of which are benthic spawners. Spawning grounds for both groups occur in a reasonably wide area that covers both Scottish landfall sites and near shore routes. Designing corridors to avoid these constraints is not possible with the landfall areas that are proposed.
6.3.4.41 PEXA and Military
6.3.4.42 Off the Firth of Forth, Corridors A and B pass through PEXA D609 for approximate distances of 60 and 65km respectively (Figure 19). This PEXA is known as ‘St Andrews’ and is used by RAF aircraft deploying missiles and sonobuoys. Corridor C does not pass through this PEXA.
6.3.4.43 Corridor A passes through approximately 80km of the western part of PEXA D513/A ('Druridge Bay’, used by the RAF for air firing), which extends offshore from approximately Berwick to Newcastle. The eastern part of Corridor B passes through the northwestern corner of this PEXA D513/A for around 20km. Corridor C does not significantly extend into this PEXA, with only a possible marginal infringement of less than 5km due east of Holy Island.
6.3.4.44 All Corridors pass through PEXA D323A/F approximately 10 to 15km east of Sunderland. This PEXA is used for air combat and training exercises. The eastern boundaries of Corridors A, C and D have the greatest extent within this PEXA (approximately 20-25km). While the western boundary of Corridor B does not cross PEXA D323A/F, the centreline and eastern section of it pass through it for a distance of a few kilometres.
6.3.4.45 NATO conducts annual subsea exercises in the waters surrounding the UK. The Joint Warrior Exercise is held twice a year and involves NATO warships, aircraft and ground troops, with each exercise lasting approximately 3 weeks. NATO exercises will have to be considered during survey and installation design and planning.
6.3.4.46 A further consideration is unexploded ordnance (UXO). During the two World Wars significant quantities of explosives were either dropped or placed in waters surrounding the British Isles. In addition there is a legacy of military activities such as dumping of unused munitions at sea. Some of this ordnance is unexploded and would present a considerable hazard if encountered and disturbed.
6.3.4.47 The cable route corridors lie clear of the majority of the main areas of known marine ordnance around the British Isles (primarily the Channel and southern coastal areas). However PMSS9 indicate a large area offshore of the east coast of the UK as a minefield, stretching the entire length of the UK. This minefield is a substantial area in which unexploded mines from both World Wars may be found. All cable routes would intersect this area. Additionally PMSS indicate that there are areas of dumped munitions and artillery ranges close to coast that Corridor C would intersect, and artillery ranges located near to Newcastle, that all corridors may intersect. Further information/surveying will be required to ensure that there is no UXO on the HVDC route.
9 PMSS, 2011. Unexploded Ordnance Risk. Considering Unexploded Ordnance Risk on and around the British Isles.
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Figure 19: PEXAs in the study area
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6.3.4.48 Firth of Forth Offshore Wind Farm
6.3.4.49 It may be possible to route the cable route within the Firth of Forth Offshore Wind Farm site, as only part of the site will be used for the turbine structures. However co-location may prove problematic as the locations of these turbine structures have not yet been identified. Again the ideal scenario would be to avoid the site, however this may mean a longer route corridor. At this stage it may be prudent to avoid the Phase 1 area (as this will be first to be developed) and avoid the shallower areas in Phase 2 and 3, as this is where the turbine structures are most likely to be sited.
6.3.4.50 Corridor B passes through the eastern part of the Firth of Forth Offshore Wind Farm (Figure 20). The western boundary of Corridor B has the longest transit through this offshore wind farm (approximately 60km), although the centreline of Corridor B passes through for a shorter distance of 31km. Corridor B passes through Phase 2 and the unnamed south eastern sector.
6.3.4.51 The wind farm developer, Seagreen, is currently undertaking zone appraisal and planning to define development sites in the zone. There are three wind farm sites planned within Phase 3 of their development, though exactly where they will be located is still unknown. The estimated construction period is 2016 to 2018.
6.3.4.52 Other Wind Farms
6.3.4.53 All Corridors south of the Tees extend across the Teesside Offshore Wind Farm, off the mouth of the River Tees near Redcar (Figure 15). It should be noted, however, that the wind farm only extends across approximately one third the width of any corridor.
6.3.4.54 Corridor C passes close to the eastern edge of the Aberdeen Offshore Wind Farm, and corridors B and C pass close to the eastern edge of the Blyth Demonstration Offshore Wind Farm.
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Figure 20: Wind farms in the study area
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6.3.4.55 Navigation
6.3.4.56 The levels of shipping across all four corridor options are moderate to high. All four corridors intersect high levels of shipping at the ports of Peterhead and Teesside (for those corridors which landfall to the south of the Tees), as well as the small area of high-density shipping further east of the coastal traffic, between Berwick-upon-Tweed and Teesside. Corridor C also intersects the high density of coastal traffic between the Firth of Forth and Teesside.
6.3.4.57 There are two Royal Yachting Association (RYA) medium-use cruising routes off the coast of Peterhead and three medium-use cruising routes in Tees Bay. There are a further three medium-use, and one light-use, cruising routes leaving the Tyne area. There are a significant number of medium-use cruising routes along the coast between Peterhead and Teesside that Corridor C is intersected by.
6.3.4.58 In addition all corridor options pass through the north-east Scotland sailing area and a racing area in Tees Bay. Corridor A also intersects a small section of the south-east Scotland sailing area.
6.3.4.59 Corridor C has higher levels of shipping than the other corridors, due to the fact that it runs through most of the coastal traffic. Therefore, from a navigational viewpoint, Corridors A, B or D would be preferred. Comparing these three options, there are only limited differences in the levels of vessel activity.
6.3.5 Constraints for which further information is required
6.3.5.1 The following environmental features will need further, more detailed study and surveying before the proposed route can be determined. The features are relatively small and at the corridor scale they are difficult to avoid.
6.3.5.2 Wrecks
6.3.5.3 Of the four corridors the number of wrecks is the greatest in Corridor C (Figure 21). Corridors A, B and D cover a comparable number of wrecks.
6.3.5.4 Areas of Mobile Sediment
6.3.5.5 Areas of mobile sediment are based on those identified in Holmes et al. (2004)10. Corridors A and D pass through approximately 32km, B through 12km and C 28km.
10 Holmes R, et al. (2004). DTI SEA Area 5: Seabed and superficial geology and processes. British Geological Survey Report CR/04/064N.
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Figure 21: Wrecks in the study area
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6.3.5.6 Areas of Exposed Bedrock and Seabed Conditions
6.3.5.7 Areas of rocky seabed have been collated from BGS 1:250,000 Quaternary Geology sheets (Tyne Tees, Farne, Marr Bank, Tay Forth and Peterhead), and are presented in Figure 22. Depth to bedrock is unknown, and some of the rock is likely to be overlain by surface sediments - Corridor A passes through approximately 12km, Corridor B through 47km, Corridor C through 61km and Corridor D between 42km and 55km.
6.3.5.8 There are a group of dykes oriented in a north-north-east direction from near the coast of Scotland (Dunbar) towards the south-west corner of the Firth of Forth Offshore Wind Farm, which Corridor C would need to cross.
6.3.5.9 The Wee Bankie Formation (Figure 22) is a glacial till comprising firm to stiff clay with a relatively high shear strength, making cable burial more difficult than in the surrounding sands and muds. All cable routes would pass through some of this formation, as it is extensive in the southern areas of all of the route corridors.
6.3.5.10 Compared to the other cable route options Corridor A passes through more of the muddier sediments (which would facilitate easier cable burial than sands and gravels) in the southern section of the HVDC area (Figure 22). Corridor D passes through more of the Wee Bankie Formation and less of the muddy sediments than Corridor A.
6.3.5.11 In terms of favourable seabed geology and avoiding exposed bedrock, Corridor A would therefore be the preferred option.
6.3.5.12 Shallows/Reefs
6.3.5.13 The shore approaches are aligned to limit the length of cable in shallow waters (i.e. the cables reach deeper water (>10m depth) relatively close to shore) (Figure 23). Apart from the landfalls, only Corridor C passes through any areas where water depths of less than 10m are present. Specifically, this relates to the Bell Rock Lighthouse, located east of the Firth of Tay, which is located close to the centre of Corridor C. Water depths for the majority of the corridor routes are between 50m and 100m. A route within Corridor C could easily avoid this shallow water area.
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Figure 22: Geology in the study area
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Figure 23: Bathymetry in the study area
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6.3.6 Corridor Summary
6.3.6.1 A summary of the four corridor options, three landfalls (Peterhead, Hawthorn Pit and Lackenby) and constraints is provided in Table 2. Distances are measured in kilometres and are taken as centrelines through the corridors (therefore whilst text in the above sections may indicate that corridors pass through certain constraints, the centrelines may not, and distances in Table 2 will reflect centreline distances rather than corridor area). Corridor D has not been considered for landfall at Hawthorn Pit, due to the impracticality of this potential route (i.e. few routeing opportunities with regards to length of route, cable burial potential and conflict with other users).
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Table 2: Summary of corridor options and constraints from Peterhead to Lackenby/Hawthorn Pit
Preferred
Corridor
Option(s)
Engineering Length 330 343 346 316 326 309 360 343 B
5 (+ 4 3 (+ 4 proposed proposed Cable & pipeline 5 5 5 3 5 3 from shore from shore A, B, D crossings to wind to wind farms) farms)
Environment Distance through 3.5 3.5 3.5 3.5 3.5 3.5 3.5 3.5 None SPA’s/SAC’s
Distance 0 0 0 0 41 41 34 34 A, D through MCZs
Proximity to protected None None None None None None None None None wrecks
Socio Shipping density Moderate Low/Mod Low/Mod Moderate Moderate Moderate High High D economic Distance 193 191 165 150 62 60 2 0 C through PEXAs
Distance through Firth of 0 0 0 0 31 31 0 0 A,C,D Forth Offshore Wind Farm
Proximal to Proximal to Proximal to Proximal to Proximal to Proximal to Proximal to Proximal to Proximity to & overlap & overlap & overlap & overlap & overlap & overlap & overlap & overlap spoil/disposal None with some with some with some with some with some with some with some with some sites sites sites sites sites sites sites sites sites
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Preferred
Corridor
Option(s)
Corridor overlap with Proximity to Corridor Corridor Corridor Corridor Teesside Proximal to Inch Cape other wind farm overlap with overlap with overlap with None overlap with None A, B, D Proximal to and Neart sites Teesside Teesside Teesside Teesside Inch Cape Na Goithe and Neart Na Goithe
Fishing density High Moderate Low High High High V. High V. High D2 (relative)
Cruden Bay Cruden Bay and Tees Cruden Bay Cruden Bay Cruden Bay Cruden Bay Passes Anchorages Cruden Bay Cruden Bay Passes A, B, D and Tees and Tees and Tees and Tees close to close to Aberdeen Aberdeen
Technical Distance and Safety through potential 28 28 32 28 12 12 28 28 B sediment waves
Distance through rock & 12 43 55 6 47 42 61 56 A potential rock
Distance through Wee 83 90 97 83 82 82 96 96 B, A Bankie Formation.
Distance through muddy 96 61 31 81 65 54 74 63 A sediments
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Preferred
Corridor
Option(s)
1 adjacent to corridor Proximity to 1 adjacent to 1 adjacent to 1 adjacent to 1 adjacent to Proximal to None None A, B, D MEHRAs corridor corridor corridor corridor Proximal to several several others
Density of Moderate Moderate Moderate Moderate Moderate Moderate High High A, B, D wrecks
Bell Rock Bell Rock Shallow/Reefs None None None None None None lighthouse in lighthouse in A, B, D corridor corridor
All distances are approximate and in km.
Where D is listed as a preferred route it refers to both D1 and D2.
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6.4 Preferred Route Corridor Option
6.4.1.1 Corridor C is deemed the least preferred option due to increased route length, increased number of potential cable crossings, increased shipping density, increased density of fishing activities, increased number of wrecks, proximity to anchorage areas near to Aberdeen, presence of shallows (Bell Rock Lighthouse) and the increased distance through potential rocky seabed areas.
6.4.1.2 From the data examined in this study, Corridor A is the most preferable option. While Corridor A is slightly longer than Corridor B, it avoids the Firth of Forth Offshore Wind Farm and MCZ NG14, it runs for a shorter distance through rock and for a greater distance through soft muddy sediments. Corridor A also passes through areas of slightly lower fishing and shipping densities than Corridor B. Corridor D, which is a modified version of Corridor A, passes through areas of lowest fishing and shipping densities, but it is longer than Corridor A and passes through less favourable geology for cable burial.
6.4.1.3 In terms of disruption to fishing activity it is useful to consider timescales of disruption as well as amount of fishing activity. Although Corridor D passes through areas with the least volume of fishing, the ground conditions are less suited for cable burial. Therefore cable lay on this route would probably involve some seabed cable armouring and may take significantly longer than Corridor A where seabed conditions are more suited for cable burial. In the areas of greatest fishing activity in Corridor A the cable would probably be laid in the seabed (trenching or ploughing) which would be a much quicker operation and may overall involve less disturbance to fishing activities.
6.4.1.4 It is therefore recommended that Corridor A and Corridor D be taken forward for further study.
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7.0 Route Refinement (500m wide corridors)
7.1 Approach
7.1.1.1 In Scotland SHETL are consulting on a preferred location for a converter station and associated infrastructure located in the vicinity of the existing Peterhead 275kV Substation. There are three options considered for cable landfall, namely the beach north of Peterhead, Sandford Bay and Cruden Bay (Section 5.3.2).
7.1.1.2 In England there are two possible converter station and associated infrastructure locations, namely Hawthorn Pit and Lackenby. The 3 landfall options considered for the Hawthorn Pit converter station and associated infrastructure are Seaham Hall Beach, Blast Beach (Nose’s Point) and Easington Colliery (Section 5.3.4). The 2 landfall options considered for the Lackenby converter station and associated infrastructure are Redcar Sands (landfall 2) and Marske Sands (landfall 3) (Section 5.3.3). The Coatham Sands landfall option (landfall 1) has not been considered for detailed routeing, as it is the least preferred near shore and onshore option.
7.1.1.3 The multiple landfall options, combined with the two 10km wide preferred corridors that were selected in Section 5.0, dictates that there will be multiple 500m wide route options. The approach to development of these routes is described below.
7.1.1.4 The centre-lines of the two selected 10km wide corridor options were divided into their constituent segments. Each segment is an individual part of the route and continues until there is an option for a route alternative. These segments were then routed inside the 10km corridors to each of the possible landfalls as described below, and shown in Figure 24. In total there are 25 individual segments, which can be used in different combinations to make up various routes. Each segment is briefly described with reference to the original 10km wide corridors in Table 3.
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Figure 24: 500m wide route segments
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Table 3: Route segment description
Brief description 1 North of Peterhead landfall. 2 Sandford Bay landfall. 2a Sandford Bay south of Peterhead Power Station landfall. 3 Cruden Bay landfall. 4 Main offshore route segment. Route bifurcates at the southern end of this section, segment 5 inside Corridor A and segment 10 inside Corridor D2. 5 Route inside Corridor A. Route trifurcates at the southern end of this section; segment 6 inside Corridor A towards Hawthorn Pit landfalls, segment 11 inside Corridor A towards Lackenby landfalls, and segment 12 inside Corridor D1. 6 Route inside Corridor A, towards Hawthorn Pit. 7 Seaham Hall Beach landfall. 8 Blast beach (north of Noses’s Point) landfall. 8a Blast beach (south of Noses’s Point) landfall. 9 Easington colliery landfall. 10 Route inside Corridor D2. 11 Route inside Corridor A. Route bifurcates at the southern end of this section, where Corridor A is greater than 10km wide. Segment 14 is towards the eastern side of Corridor A and segment 13 one towards the western side of Corridor A. 12 Route inside Corridor D1. 13 Route inside Corridor A, towards western side. 14 Route inside Corridor A, towards eastern side. 15 Route inside Corridor D2 for Redcar Sands. 16 Route inside Corridor A, towards eastern side, for Redcar Sands. 17 Segment where Corridors D1 and D2 converge for Redcar Sands. 18 Redcar Sands landfall. 19 Route inside eastern side of Corridor A towards Marske Sands. 20 Route inside Corridor D1 for Marske Sands. 21 Route inside Corridor D2 for Marske Sands. 22 Route where eastern edge of Corridor A and Corridor D converge for Marske Sands. 23 Corridor D route towards Marske Sands. 24 Corridor A route towards Marske Sands. 25 Marske Sands landfall
Segment occurs in routes with a landfall for Hawthorn Pit converter station and associated infrastructure Segment occurs in routes with a landfall at Redcar Sands for Lackenby converter station and associated infrastructure Segment occurs in routes with a landfall at Marske Sands for Lackenby converter station and associated infrastructure
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7.1.1.5 After the centre lines of the original corridors were plotted and divided into constituent segments, each segment was aligned to avoid ‘no go’ constraints, or minimise distance through other constraints (Table 4) whilst staying within the original 10km wide corridor as far as possible. Routeing opportunities that were targeted were the shortest route, the greatest potential for burial, the least conflict with other users of the sea and the least impact to the environment.
7.1.1.6 During this more detailed phase of routeing some constraints, such as wrecks become ‘no go’ areas and were routed around, giving at least 150m clearance. Furthermore, where possible and feasible, known areas of exposed bedrock and other areas with seabed poorly suited for cable burial were avoided, or distances through these areas minimised. The corridors were routed to cross existing cables and pipelines at 90°. Spoil grounds and marine protected areas were avoided except where this was impossible.
7.1.1.7 In some cases it was not feasible to stay fully within the original 10km corridors due to the prevalence of wrecks and poor seabed conditions, and as such, in some places the 500m routes pass outside of the 10km corridor boundaries.
7.1.1.8 In Sandford Bay there are two possible landfall locations identified, namely segments 2 and 2a described in Section 5.3.2.1. At Blast Beach there are two possible landfall locations identified namely segments 8 and 8a described in Section 5.3.4.8.
7.1.1.9 The routeing of each segment is described in detail in Section 7.2.
Table 4: Constraints summary for 500m wide corridor options
Areas subject to negotiation
Marine Conservation Areas of mobile sediment Pipeline/cable crossings (route Zone Reference Areas at 90°). Designated anchorage Areas of exposed bedrock Environmentally sensitive and zones protected areas (e.g. SPA, SAC) Dredged channels Other areas of other seabed poorly Marine Conservation Zones suited for cable burial (e.g. Wee Bankie Fmn, boulder fields, gravelly areas) Protected wrecks Other geological constraints (e.g. Important fishing grounds glacially incised valleys) Wrecks Disposal areas (spoil grounds) PEXA Important areas for navigation Wind farm development blocks and associated cable routes and connections
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7.2 Route Description
7.2.1 Detailed Segment Description
7.2.1.1 Segments mapped onto Admiralty charts, with constraints and opportunities plotted, are presented as Figure 25 to 31, with a legend given as Figure 26
7.2.1.2 Segment 1
7.2.1.3 The route heads on a bearing of 083° from the landfall at the southern end of the beach north of Peterhead. The route is straight until the 10m depth contour, keeping clear of rocky headland to the south, and then turns approximately due east and passes between a spoil ground to the south and a wreck to the north. The route then turns to the south-east, skirting the corner of the spoil ground.
7.2.1.4 The route reaches 5m water depths after 415m and 10m water depths after a further 440m (from Chart Datum).
7.2.1.5 Segment 2
7.2.1.6 The route heads approximately due east out of Sandford Bay and passes into the Buchan Ness to Collieston Coast SPA, the centre-line of the route remaining within the SPA for 1.3km. The centre-line of the route also passes through a spoil ground for 0.7km. The outfalls that flow onto the spoil ground discharge tertiary treated sewage, and this should limit the amount of material which is being added to the spoil ground.
7.2.1.7 There is a power station outfall in Sandford Bay. From examination of satellite imagery the power of the outfall appears to be such that protection methods (e.g. rock dumping) for a laid cable will need to be considered. The water temperature of the power station outfall will need to be ascertained to ensure that it poses no thermal constraints to the cable design.
7.2.1.8 The route kinks around the two sewage outfall pipelines in the spoil ground, and then heads north-east out of the SPA. The route then turns due east crossing the leading light into Peterhead harbour. The route then heads south-east, paralleling the leading light but staying 1.75km offshore of it.
7.2.1.9 The route reaches 5m water depths after 400m and 10m water depths after a further 270m.
7.2.1.10 Segment 2a
7.2.1.11 This offshore segment would be used for a potential horizontal directional drill landfall option, located south of Peterhead Power Station (directly south of Sandford Bay). This route will avoid the outflow from the power station outfall. The route heads north-east from the shore and joins segment 2 after 1.35km. The route avoids the rocks and wrecks around “The Skerry”. The route passes through 1.1km of SPA and 0.4km of spoil ground.
7.2.1.12 The route reaches 5m water depths after 220m and 10m water depths after a further 110m.
7.2.1.13 Segment 3
7.2.1.14 The route heads north-east out of Cruden Bay, with the centre-line approximately 100m from the rocky headland to the north and 100m from the existing cable to the south. The route follows the existing cable and pipelines east-north-east out of Cruden Bay, keeping 100-150m to north of them. The route has a slight kink, turning due east in order to avoid
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two wrecks near the corridor. The route passes through 4km of the Buchan Ness to Collieston Coast SPA.
7.2.1.15 The route reaches 5m water depths after 850m and 10m water depths after a further 600m.
Figure 25: Segments 1, 2, 2a and 3 constraints
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Figure 26: Legend for Figures 25 to 31
7.2.1.16 Segment 4
7.2.1.17 The route crosses the two Cruden Bay – Forties pipelines and the CNS cable at 90°, then heads south-east for 10km, before kinking slightly south for 30km in between wrecks and avoiding deeps to the west (which may be steep sided glacially incised valleys). The route then heads at a bearing of 174° in-between wrecks and avoiding coarser sediments (gravel) before heading on a bearing of 167° to the end of the route segment.
7.2.1.18 Segment 5
7.2.1.19 The route heads south on a bearing of 170°, before turning slightly south onto a bearing of 176°. The route passes between MCZ14 and MCZ15, keeping 3km east of mapped rock outcrops and west of several wrecks. The route also minimises distance through the Wee Bankie till formation. The route then turns onto a bearing of 191°, avoiding the south eastern corner MCZ14 and passing between the Farn Deeps and an area of rock outcrops to the east, and an area of deeps to the west (which may be steep sided glacially incised valleys). At the south-east corner of the MCZ the route passes into an area of high fishing intensity which correlates well with muddy sand seabed sediments.
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Figure 27: Segment 4 constraints
Figure 28: Segments 5 and 10 constraints
7.2.1.20 Segment 6
7.2.1.21 The route heads on a bearing of 183°, in between several wrecks on either side.
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Figure 29: Segments 6, 10 to 15 and 21 constraints
7.2.1.22 Segment 7
7.2.1.23 The route heads on a bearing of 210° between several wrecks, before kinking onto a bearing of 250°, then heading eastwards to make landfall at Seaham Hall Beach. The route is in water depths of between 5 and 10m for 485m and water depths less than 5m for 500m (from Chart Datum).
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7.2.1.24 Segment 8 & 8a
7.2.1.25 The route heads on a bearing of 203° between several wrecks, before kinking northwards twice and making landfall north of Nose’s Point. An option for this segment is to make landfall to the south of Nose’s Point (Segment 8a).
7.2.1.26 Both route options avoid a circular spoil ground the centre of which is located 1.1km east of Nose’s Point and a sewage pipeline that extends seaward for 1.5km from the southern end of Nose’s Point on a bearing of 110°.
7.2.1.27 The route (segment 8) is in water depths of between 5 and 10m for 485m and water depths less than 5m for 270m (from Chart Datum). For segment 8a the route is in water depths of between 5 and 10m for 610m and water depths less than 5m for 150m (from Chart Datum).
7.2.1.28 Segment 9
7.2.1.29 The route heads on a bearing of 193°, in between a couple of wrecks and keeping in muddier sediments for as long as possible. The route then turns to 220° in-between several wrecks, before turning to make a perpendicular approach to the landfall at Easington Colliery. The route is in water depths of between 5 and 10m for 750m and water depths less than 5m for 335m (from Chart Datum).
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Figure 30: Segments 7, 8, 8a and 9 constraints
7.2.1.30 Segment 10
7.2.1.31 The route heads on a bearing of 164°, in-between MCZ14 and MCZ15, avoiding coarser sediments and wrecks. The route then bends around a large area of rock outcrop and also an area marked as ‘wrecks graveyard’, also keeping clear of the areas of high intensity fishing to the west. Once past the wrecks graveyard, the route heads on a bearing of 193°, across bedrock for 5km, and then avoids further rock outcrop and slightly coarser sediments to the west. The route then makes two kinks, the first to cross the CATS pipeline and the second to cross the NORPIPE both crossings being at right angles.
7.2.1.32 Segment 11
7.2.1.33 The route heads south passing between several wrecks. The route is over muddy sand sea bed sediments and avoids any of the Wee Bankie Formation.
7.2.1.34 Segment 12
7.2.1.35 The route heads south-east on a bearing of 153°, keeping at least 2km clear of the large area of rock outcrop to the east. The route kinks at 90° over the two pipelines before heading on a bearing of 191°.
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7.2.1.36 Segment 13
7.2.1.37 The route heads on a bearing of 175°, before a slight kink onto a bearing of 182°, thus passing between some wrecks. The route then kinks over NORPIPE at 90° and passes approximately equidistant from two spoil grounds to the east and west. The route then kinks to cross over the CATS pipeline at 90° and heads on a bearing of 185°, keeping 450m east of a beacon with a north mark.
7.2.1.38 Segment 14
7.2.1.39 The route heads south-east on a bearing of 150°, between several wrecks, avoiding the Wee Bankie Formation to the east while avoiding the areas with the greatest fishing density to the east. The route then passes over the two pipelines at right angles.
7.2.1.40 Segment 15
7.2.1.41 The route heads on a bearing of 202°
7.2.1.42 Segment 16
7.2.1.43 The route heads south-west on a bearing of 214°, in-between a number of wrecks on either side.
7.2.1.44 Segment 17
7.2.1.45 The route heads south-east on a bearing of 229°, before kinking slightly north between 2 wrecks for the last 330m of this segment.
7.2.1.46 Segment 18
7.2.1.47 The route heads straight to the landfall at Redcar Sands on a bearing of 229°, avoiding rocks close to shore. The route is in water depths of between 5 and 10m for 1.3km and water depths less than 5m for 620m (from Chart Datum).
7.2.1.48 Segment 19
7.2.1.49 The route heads on a bearing of 170°.
7.2.1.50 Segment 20
7.2.1.51 The route heads on a bearing of 192°, connecting segments 12 and 15 to segment 22.
7.2.1.52 Segment 21
7.2.1.53 The route heads on a bearing of 192°, before kinking over the CANTAT 3 F4 (BT) cable and the PANGEA NORTH UK/DNK cable, crossing both cables at 90°. The route then heads on a bearing of 234°.
7.2.1.54 Segment 22
7.2.1.55 The route heads on a bearing of 152°, before kinking over the CANTAT 3 F4 (BT) cable in- between two wrecks and then kinking over the PANGEA NORTH UK/DNK cable, crossing both cables at 90°.
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7.2.1.56 Segment 23
7.2.1.57 The route heads on a bearing of 240°, in between two wrecks, towards landfall.
7.2.1.58 Segment 24
7.2.1.59 The route kinks over both the CANTAT 3 F4 (BT) cable and the PANGEA NORTH UK/DNK cable, crossing both cables at 90°. The route also passes over a disused cable marked on the Admiralty chart.
7.2.1.60 Segment 25
7.2.1.61 The route heads into the landfall at Marske Sands perpendicular to the coast. The route is in water depths of between 5 and 10m for 780m and water depths less than 5m for 670m (from Chart Datum).
Figure 31: Segments 13 and 16 to 25 constraints
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7.2.2 Route Options
7.2.2.1 The 25 segments can be combined to form a total of 44 possible routes. If the 4 landfalls near to Peterhead are taken as options for each route then the number of routes can be simplified to 11. Therefore the routes described in the following sections are routes from the beginning of segment 4 only, and do not include the Scottish landfalls segments (1, 2, 2a or 3). These 11 routes will be referred to by landfall and letter:
Hawthorn Pit (HP) A, B and C;
Redcar Sands (RS) A, B, C and D; and
Marske Sands (MS) A, B, C and D;
and can be clarified by options 1, 2, 2a or 3 to differentiate between the Scottish landfall sites.
7.2.2.2 The routes are given in Figures 32, Figure 33 and Figure 34, along with total route lengths for each option.
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Figure 32: 500m wide corridors options. Routes HP A, HP B and HP C.
Route HP A Segments: 4,5,6,7 Options Length (km) 1 318.2 2 313.3 2a 312.9 3 314.1
Route HP B Segments: 4,5,6,8 Options Length (km) 1 319.7 2 314.7 2a 314.3 3 315.5
Route HP B (a) Segments: 4,5,6,8a Options Length (km) 1 321.0 2 316.0 2a 315.6 3 316.9
Route HP C Segments: 4,5,6,9 Options Length (km) 1 323.4 2 318.4 2a 318.0 3 319.2
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Figure 33: 500m wide corridor options. Routes RS A, RS B, RS C and RS D.
Route RS A Segments: 4,5,11,13,18
Options Length (km) 1 341.2 2 336.3 2a 335.9 3 337.1
Route RS B Segments: 4,5,11,14,16,18 Options Length (km) 1 348.9 2 343.9 2a 343.5 3 344.7
Route RS C Segments: 4,5,12,17,18 Options Length (km) 1 353.6 2 348.7 2a 348.3 3 349.5
Route RS D Segments:4,10,15,17,18 Options Length (km) 1 355.8 2 350.8 2a 350.4 3 351.6
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Figure 34: 500m wide corridor options. Routes MS A, MS B, MS C and MS D.
Route MS A Segments: 4,5,11,13,24,25 Options Length (km) 1 342.5 2 337.5 2a 337.1 3 338.3
Route MS B Segments: 4,5,11,14,19,22,23,25 Options Length (km) 1 353.9 2 349.0 2a 348.6 3 349.8
Route MS C Segments: 4,5,12,20,22,23,25 Options Length (km) 1 355.5 2 350.5 2a 350.1 3 351.4
Route MS D Segments: 4,10,21,23,25 Options Length (km) 1 358.5 2 353.6 2a 353.2 3 354.4
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7.2.2.3 Details of each route, and constraints/opportunities in each route, are given in Table 5. Distances are given in kilometres, and any lengths that reach the shore are taken from Chart Datum.
7.2.2.4 Fishing density is relative, and has been estimated by examining plots of vessel sightings in the study area.
7.2.2.5 Distances through seabed sediments, quaternary units and exposed rocks have been calculated by examination of BGS seabed sediment and quaternary data11, along with Seazone data12. Distances through potential rock/gravel are taken from BGS (1986) Tyne Tees Sheet, from the bedform distribution dataset, which is of a significantly lower resolution than the seabed sediment and quaternary data, and as such should only be taken as an approximate guide. Seabed sediment abbreviations are given at the base of Table 5.
7.2.2.6 Geological units referred to in Table 5 are described briefly below:
Forth Formation: Glaciomarine muds, silts and sands, with variable quantities of small pebbles;
St. Abbs Formation: Glaciomarine muds and clays with sporadic small pebbles;
Wee Bankie: Glacial till, comprising firm to stiff clay, typically occurring as a veneer on bedrock; and
Marr Bank: Glaciomarine mud, silts and fine sands commonly with small pebbles.
11 BGS, 1986. Peterhead Sheet 57°N-02°W. British Geological Survey 1:250000 Series. Quaternary Geology. BGS, 1985. Marr Bank Sheet 56°N-02°W. British Geological Survey 1:250000 Series. Quaternary Geology. BGS, 1987. Tay Forth Sheet 56°N-04°W. British Geological Survey 1:250000 Series. Quaternary Geology. BGS, 1988. Farne Sheet 55°N-02°W. British Geological Survey 1:250000 Series. Quaternary Geology. BGS, 1986. Tyne Tees Sheet 57°N-02°W. British Geological Survey 1:250000 Series. Seabed Sediments and Quaternary Geology. 12 SeaZone, 2011. SeaZone Solutions – Marine Geographic Information Solutions from Instrument to Desktop. Available [Online] at http://www.seazone.com/index.php
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Table 5: Offshore route descriptions
Rock (km)
unknown 1.9 (g)sM 0.0 Forth Fmn 88.5 Hawthorn mS 79.5 Low St. Abbs Fmn 2.6 Pit A (g)mS 4.9 Exposed Rock 0 Moderate 1.7 Wee Bankie 61.0 298.3 3 119 gmS 0.0 Potential rock or High 74.6 Marr Bank 124.0 2.4 Segments 213.0 S 111.8 gravel V. High 9.0 Unknown/<1m 4,5,6,7 22.7 (g)S 54.7 thick gS 44.0 sG 1.5 unknown 1.8 (g)sM 0.0 Forth Fmn 88.5 Hawthorn mS 80.0 Low St. Abbs Fmn 2.6 Pit B (g)mS 4.1 Exposed Rock 0 Moderate 1.0 Wee Bankie 61.0 299.7 3 119 gmS 0.0 Potential rock or High 75.6 Marr Bank 124.0 3.9 Segments 214.0 S 111.8 gravel V. High 9.0 Unknown/<1m 4,5,6,8 24.1 (g)S 53.4 thick gS 45.1 sG 3.7 unknown 2.2 (g)sM 7.7 Forth Fmn 88.5 Hawthorn mS 78.4 Low St. Abbs Fmn 2.6 Pit C (g)mS 4.6 Exposed Rock 0 Moderate 2.0 Wee Bankie 61.0 303.4 3 119 gmS 0.0 Potential rock or High 75.6 Marr Bank 124.0 5.9 Segments 216.0 S 111.8 gravel V. High 9.5 Unknown/<1m 4,5,6,9 27.8 (g)S 53.4 thick gS 44.0 sG 1.5
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Rock (km)
unknown 0.9 (g)sM 0.0 Redcar Forth Fmn 78.5 mS 101.1 Sands A Low St. Abbs Fmn 13.5 (g)mS 4.5 Exposed Rock 0 Moderate 0.0 Wee Bankie 61.0 321.3 5 140 gmS 0.0 Potential rock or Segments High 64.6 Marr Bank 124.0 9.4 223.6 S 114.6 gravel 4,5,11,13, V. High 33.0 Unknown/<1m 45.1 18 (g)S 54.9 thick gS 44.0 sG 1.5 unknown 0.9 (g)sM 0.0 Redcar Forth Fmn 78.5 mS 88.2 Sands B Low St. Abbs Fmn 14.5 (g)mS Exposed Rock 0 Moderate 22.9 3.5 Wee Bankie 61.0 328.9 5 156 Potential rock or Segments High 86.1 gmS 0.0 Marr Bank 124.0 13.9 219.9 gravel S 4,5,11,16, V. High 0.0 132.1 Unknown/<1m 51.8 (g)S thick 18 58.9 gS 44.0 sG 1.5 unknown 0.9 (g)sM 0.0 Redcar Forth Fmn 70.5 mS 61.9 Sands C Low St. Abbs Fmn 4.0 (g)mS Exposed Rock 0 Moderate 12.0 10.0 Wee Bankie 82.0 333.7 5 192 Potential rock or Segments High 63.8 gmS 1.6 Marr Bank 124.0 32 257.8 gravel S 4,5,12,17, V. High 0.0 148.6 Unknown/<1m 52.8 (g)S thick 18 59.5 gS 49.5 sG 1.5
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Rock (km)
unknown 0.9 (g)sM 0.0 Redcar Forth Fmn 56.0 mS 4.9 Sands D Low St. Abbs Fmn 0.0 (g)mS 5.5 Exposed Rock 5 Moderate 12.0 Wee Bankie 95.0 335.8 5 165 gmS 1.6 Potential rock or Segments High 0.0 Marr Bank 124.0 35.3 323.8 S 170.4 gravel 4,10,15,17 V. High 0.0 Unknown/<1m 61.3 , 18 (g)S 104.6 thick gS 48.3 sG 0.0 unknown 1.1 (g)sM 0.0 Marske Forth Fmn 78.5 mS 100.4 Sands A Low St. Abbs Fmn 13.5 (g)mS Exposed Rock 0 Moderate 0.0 8.1 Wee Bankie 61.0 322.5 7 140 Potential rock or Segments High 64.6 gmS 0.0 Marr Bank 124.0 9.4 224.9 gravel S 4,5,11,13, V. High 33.0 112.8 Unknown/<1m 46.4 (g)S thick 24,25 54.9 gS 44.0 sG 1.5 unknown 1.1 Marske (g)sM 0.0 Forth Fmn 78.5 Sands B mS 78.1 Low St. Abbs Fmn 14.5 (g)mS Exposed Rock 0 Moderate 30.2 14.2 Wee Bankie 61.0 Segments 334.0 7 163 Potential rock or High 86.1 gmS 0.0 Marr Bank 124.0 16.4 217.7 gravel 4,5,11,14, S V. High 0.0 130.7 Unknown/<1m 19,22,23,2 56.8 (g)S 56.4 thick 5 gS 52.2 sG 1.5
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Rock (km)
unknown 1.1 (g)sM 0.0 Marske Forth Fmn 70.5 mS 57.0 Sands C Low 217.7 St. Abbs Fmn 4.0 (g)mS Exposed Rock 0 Moderate 30.2 18.7 Wee Bankie 82.0 335.5 7 195 Potential rock or High 86.1 gmS 0.0 Marr Bank 124.0 34 Segments gravel S 4,5,12,20, V. High 0.0 146.8 Unknown/<1m 54.7 (g)S thick 22,23,25 58.1 gS 52.3 sG 1.5 unknown 1.1 (g)sM 0.0 Marske Forth Fmn 56.0 mS 0.0 Sands D Low 319.8 St. Abbs Fmn 0.0 (g)mS Exposed Rock 5 Moderate 18.8 13.9 Wee Bankie 95.0 338.6 7 156 Potential rock or High 0.0 gmS 0.0 Marr Bank 124.0 27 Segments gravel S 4,10,21,23 V. High 0.0 169.0 Unknown/<1m 64.1 (g)S thick ,25 102.2 gS 52.8 sG 0.0 Seabed sediment abbreviations (g)sM Slightly gravelly sandy mud
mS Muddy sand (g)mS Slightly gravelly muddy sand gmS Gravelly muddy sand S Sand (g)S Slightly gravelly sand gS Gravelly sand sG Sandy gravel
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7.2.3 Route Appraisal
7.2.3.1 Areas of difficult ground conditions for cable burial should be avoided where possible. These areas will include rocks and glacial till, such as the Wee Bankie Formation. In addition gravels are often associated with subcropping bedrock and till and are generally best avoided. In general cable burial is easier in muds and sands and more difficult in gravelly sands and gravel.
7.2.3.2 Figure 35 graphically compares the amount of rock, potential rock/gravel and Wee Bankie Formation that each of the routes crosses. Note that the distances given for potential rock/gravel are only approximate. Figure 36 graphically compares the amounts of seabed sediments that each of the routes cross. Figure 37 graphically compares the fishing intensity along each of the routes.
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Figure 35: Rock and till exposures along routes
160 Exposed Rock 140 Potential Rock/Gravel Wee Bankie Fmn 120
100
80 km
60
40
20
0 HP A HP B HP C RS A RS B RS C RS D MS A MS B MS C MS D Route
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Figure 36: Seabed sediment compositions along routes
100% sG 90% gS (g)S 80% S
70% gmS (g)mS 60% mS (g)sM 50% unknown
40%
30%
20%
10%
0% HP A HP B HP C RS A RS B RS C RS D MS A MS B MS C MS D Route
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Figure 37: Relative fishing intensity along routes
100%
90%
80%
70%
60% V. High High 50% Moderate 40% Low
30%
20%
10%
0% HP A HP B HP C RS A RS B RS C RS D MS A MS B MS C MS D Route
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7.2.3.3 Table 6 shows the rankings of the routes in terms of length, pipeline and cable crossings, rock and till exposures, seabed sediment composition and fishing intensity. All routes avoid the no go areas given in Table 4 and also avoid MCZs and wind farm development blocks. Only segments 2, 2a and 3 pass through marine environmentally designated areas. As routes have been appraised without the Peterhead landfall segment included (segments 1, 2, 2a or 3) marine environmentally designated areas are not a factor in the route comparison. Similarly only segments 2 and 2a pass through marine disposal areas, and thus these are not considered in the comparison below. Distance through PEXAs carries little weighting comparatively and thus has not been included in route comparison (Table 6).
Table 6: Offshore route comparison
Fishing
intensity
Most HP A = HP A = HP A RS A = RS D Preferred 2 HP B = HP B = HP B MS A = MS D 3 HP C HP C = HP C HP C RS C 4 RS A = = RS A RS A = HP A = MS C 5 MS A = = RS B MS A = HP B = RS B 6 RS B = RS C RS B RS B MS B 7 RS C = = RS D MS B MS B = HP A 8 MS B = MS A = RS C RS C = HP B 9 = MS C MS B = MS C MS C = HP C 10 = RS D MS C = MS D RS D RS A = Least MS D MS D = HP A MS D MS A = Preferred
7.2.3.4 If each criteria are given equal weighting and a simple scoring system used where 10 points are accrued for most preferred to 0 points for least preferred, the routes can be ranked according to all the criteria in Table 6. Routes that are ranked equally score equal points equivalent to the lowest ranked equal score i.e. for pipeline and cable crossings HP A, HP B and HP C all score 8 points. Route lengths within 2km of each other are considered equivalent. If this system is employed then the ranking given in Table 7 is achieved.
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Table 7: Offshore route ranking Score HP A 35 HP B = 34 HP C = 34 RS A 25 RS B 24 RS C = 21 MS A = 21 RS D 16 MS B 16 MS C 12 MS D 10
7.2.3.5 All the Hawthorn Pit routes (HP A, HP B and HP C) rank similarly highly, with HP A the highest ranked due to shortest length and shortest distance through potential rock and gravel.
7.2.3.6 After the Hawthorn Pit routes it can be seen that the next highest ranked routes are RS A and RS B, followed by RS C and MS A. The lowest ranked routes are MS D, MS C, MS B and RS D. These routes rank low due to increased number of cable crossings for the MS routes, and greater overall lengths and greater distances through rock and till and less suitable seabed sediments for RS D and MS D.
7.2.4 Peterhead Landfall Options
7.2.4.1 Peterhead landfall options are the beach north of Peterhead (segment 1), Sandford Bay (segments 2 and 2a) and Cruden Bay (segment 3). These landfall options are described in Section 5.3. A brief overview of the engineering opportunities and constraints for these four landfall options is given below
7.2.4.2 All four proposed landing sites can be constructed using conventional technologies; the landing south of Peterhead Power Station (2a) will require the use of a horizontally directionally drilled (HDD) duct whilst the others can be installed by using open cut trenching (or a combination of the two methods). They have differing levels of anthropogenic constraints with Sandford Bay being the most constrained and the north of Peterhead landing the least (Section 5.3). However from an installation viewpoint the shortest cable float-in will be for 2a, the south of Peterhead Power Station landing, followed by Sandford Bay, north of Peterhead and the longest at Cruden Bay.
7.2.4.3 The three open cut landings (i.e. Sandford Bay, Cruden Bay and north of Peterhead) are likely to encounter boulder fields or bedrock outcrops landward of the cable lay vessel stand-off positions and are likely to require either rock dumping (if bedrock outcrops to the seabed) or possibly the use of a back-hoe dredger (if boulder fields are present).
7.2.4.4 The length and the more exposed nature of the cable pull-ins at Cruden Bay and to a lesser extent north of Peterhead may mean a cable lay barge is required for the inshore installation. It is probable that mobile inshore sandbanks are present at the landings north of
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Peterhead and in Cruden Bay and these will potentially require deeper burial to ensure the cables do not become exposed due to the sandbank migration.
7.2.4.5 The marine and near shore aspects of these landfalls are compared in Table 8.
Table 8: Peterhead landfalls options comparison Possible
boulder
fields Most Preferred 2 / 2a 1 1 = 2 / 2a 2 / 2a 2 3 2 / 2a 3 = = 3 = 3 Least Preferred 1 3 2 / 2a = 1 = 1
7.2.4.6 If a scoring system is used as in Section 7.2.3 then the ranking given in Table 9 is achieved.
Table 9: Peterhead landfall options ranking Score 2 / 2a 12 1 8 3 7
7.3 Preferred options
7.3.1.1 The offshore route preferences determined here are based on the offshore appraisal contained in this report. The identification of a preferred landfall needs to take into account not only the offshore route comparison, but also needs to consider those for the onshore routes.
7.3.1.2 At this stage the preferred onshore routes have been determined for Scotland, however further investigation is required before these are determined for England.
7.3.1.3 The rankings of the landfall options from the Scotland Onshore Works Consultation Document is given in Table 10.
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Table 10: Ranking of landfall options from Scotland Onshore Works Consultation Document
Peterhead
Sandford Bay Most Preferred (2 landfall sites are not differentiated) Beach north of Peterhead
Least Preferred Cruden Bay
7.3.1.4 The Scotland Onshore Works Consultation Document concludes that when combined with onshore routeing criteria, the landfall at Sandford Bay is the most preferred option (no differentiation between the two landfall sites), followed by the beach north of Peterhead. Therefore when the ranking of the offshore routes is combined with this onshore routeing the overall preferred landfall at Peterhead is Sandford Bay (segment 2 or 2a).
7.3.1.5 The three offshore Hawthorn Pit routes all achieve very similar scores, with HP A scoring 1 point more than the two other options partially due to its shorter length and shorter distance through potential rock and gravel. Given that there are only minor differences in the scores for the offshore route options, the preferred onshore route could have a large bearing in determining overall preference.
7.3.1.6 As the onshore routes for the English end of the cable are still awaiting assessment, all three routes for Hawthorn Pit will remain under consideration.
7.3.1.7 For a converter station and associated infrastructure at Lackenby two landfalls were considered for offshore routeing. Out of these Redcar Sands scores consistently higher, and thus is the preferred landfall for Lackenby.
7.3.1.8 The preferred offshore route at Lackenby is landfall RS A.
7.3.1.9 Out of these marine routes the Hawthorn Pit routes are preferred over Redcar Sands (RS A) as they are shorter.
7.3.1.10 Therefore the overall preferred routes at this stage are Hawthorn Pit A, B or C, option 2 or 2a. Bathymetry and depth profile of route HP C, option 2a has been plotted as Figure 38.
7.3.1.11 Due to the fact that onshore routeing preferences in England have not yet been determined, the three Hawthorn Pit marine routes and the Redcar Sands (RS A) marine route will all be subject to survey.
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Figure 38: Route HP C, option 2a bathymetry and depth profile
0
-20
-40
-60 Depth (metres) -80
-100 0 50 100 150 200 250 300 350 Km
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APPENDIX 1 – Data Sources
Web Link
Crown Estate http://www.thecrownestate.co.uk/
4C http://www.4coffshore.com/wind farms/ Wind farms Round 3 Firth of Forth http://www.scotland.gov.uk/Resource/Doc/295194/01145 Phase 1 Scoping Report 66.pdf
Oil and Gas Department of Energy infrastructure https://www.og.decc.gov.uk/ and Climate Change and pipelines Kingfisher Information http://www.kisca.org.uk/charts.htm Service and Charts SSE (Moray Underground http://www.sse.com/uploadedFiles/Z_Microsites/Shetland HVDC Cable and /Controls/Lists/Resources/MoraySummary.pdf Cables converter station) Northconnect
(HVDC interconnector http://www.northconnect.no/ between Norway and the UK) MAGIC interactive map http://magic.defra.gov.uk/ UK Marine Protected http://www.ukmpas.org/ Areas Centre The North Sea Marine Conservation Zones http://www.netgainmcz.org/ Project Development of a Marine Framework for Mapping http://www.searchmesh.net/default.aspx Conservation European Seabed Habitats (MESH) Joint Nature http://www.jncc.gov.uk/ Conservation Committee
http://www.scotland.gov.uk/Topics/marine/science/asses Scotland Marine Atlas sment/atlas
Natural England http://www.naturalengland.org.uk/
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UK Strategic http://www.offshore Environmental sea.org.uk/site/scripts/sea_archive.php Assessment Development of a Framework for Mapping http://www.searchmesh.net/default.aspx Marine European Seabed Geology Habitats (MESH) British Geological http://www.bgs.ac.uk/ Survey Scottish Government http://www.scotland.gov.uk/Resource/Doc/295194/01080 (geology and bathymetry 12.pdf - across UK seabed)
http://www.historic Historic Scotland scotland.gov.uk/index/heritage/wrecksites.htm
http://www.english English Heritage Protected heritage.org.uk/discover/maritime/map/ Wrecks
http://www.dft.gov.uk/mca/mcga07home/emergencyresp Dept. of Transport onse/mcga-receiverofwreck/mcga-protectedwrecks.htm
Marine Management http://www.marinemanagement.org.uk/fisheries/index.ht Organisation (MMO) m fisheries
Dept. of Transport http://webarchive.nationalarchives.gov.uk/+/ Marine Environmental http://www.dft.gov.uk/pgr/shippingports/shipping/elc/secm High Risk Areas ehras/ Fisheries & http://www.scotland.gov.uk/Topics/marine/science/asses Shipping Scotland Marine Atlas sment/atlas -
UK Strategic http://www.offshore Environmental sea.org.uk/site/scripts/sea_archive.php Assessment Centre for Environment, Fisheries & Aquaculture http://www.cefas.co.uk/ Science
Dredging Crown Estate http://www.thecrownestate.co.uk/dredge_areas_statistics
Landfall area information – Good Beach Guide http://www.goodbeachguide.co.uk presence of cliffs, beach type, Google maps (satellite http://maps.google.co.uk gradient, imagery)
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recreational usage Streetmap (OS maps) http://www.streetmap.co.uk/
SHETL (Keeping the http://www.ssepd.co.uk/uploadedFiles/TPCR5_Green_Pa Lights On Green Paper) per.pdf
Electricity Networks http://webarchive.nationalarchives.gov.uk/201009191816 Strategy Group 07/http:/www.ensg.gov.uk/assets/1696-01 (2020 vision) ensg_vision2020.pdf%20/
Scottish government Planning and http://www.scotland.gov.uk/Topics/marine/marine legislation (MPA developments) environment/mpanetwork/mpaguidelines / NPF2
UK government (Marine and Coastal http://www.legislation.gov.uk/ukpga/2009/23/contents Access Act 2009) UK Government http://www.scotland.gov.uk/Resource/Doc/295194/01152 (UK Marine Policy 42.pdf Statement) UKHO Admiralty charts – navigation channels Base and water depths, Mapping anchorage areas, PEXA areas, disposal sites.
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APPENDIX 2 – Data Received From Consultees
Data received Aberdeen Port Coordinates of designated anchoring area near Aberdeen Bay. The number of vessels using the area. Other areas of anchorage outside of the designated area. Coordinates of Aberdeen spoil ground. PD Ports Information on the dredging of the Tees channel and vessel anchorage in the area. Peterhead Power Station Advised of an application for a CCS project in the vicinity of the corridor routes. NorthConnect Advised that the NorthConnect Project is currently in the early stages of development, and that a screening/scoping stage will be undertaken in November 2011. Preliminary project information relating to the capacity, preferred UK landfall and proposed routeing was also provided (see section 5.3.2.28 Aberdeen Wind Farm Project Deployment date is as yet unknown, however, (Vattenfall) deployment will either be phased over two years (2013/14) or in a single year. Potential interactions between the two developments are discussed, along with proposed exclusion and safety zones around the structures and construction works. MoD (Royal Navy) Advised that Corridor Option C would pass through Exercise Area ‘Forth Middle’. Historic Scotland Listed coastal features to be considered during landfall works.
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