DOCUMENT 7.19

Design Guide Proposed Tunnel Head Houses & Permanent Site Landscaping National Grid (North Wales Connection Project)

Regulation 5(2)(q) of the Infrastructure Planning (Applications: Prescribed Forms and Procedure) Regulations 2009

Application Reference EN020015 September 2018

Environmental Statement Chapter # iii Ecology and Nature Conservation Document #.#

Document Control

Document Properties

Organisation Jacobs

Author Nivedita Vijayan

Approved by Stewart Samson

Title Tunnel Head House Design Guide

Document Reference 7.19

Version History

Date Version Status Description/Changes

Sep 2018 A Final First Issue

North Wales Connection Project 1.0 Introduction 4 1.1 Background to the Project 4 CONTENTS 1.2 Purpose and Structure of the Report 5 1.3 Proposed Infrastructure 6 1.4 Design Context 8 1.5 Initial Stakeholder Engagement 10 2.0 Braint Tunnel Headhouse and CSEC 12-36 2.1 Introduction 12 2.2 Regional Context 13 2.3 Strategic Landscape Context 14 2.4 Landscape Designations 16 2.5 Sensitive Visual and Cultural Heritage Receptors 18 2.6 Site and Wider Context Analysis 19 2.7 Vision, Design Options & Principles - Braint 24 2.7.1 Vision and Design Approach 24 2.7.2 Braint Site Building Form Preferred Option and Key Design Principles 26 2.7.3-2.7.5 Braint Site Building Form Initial Options 28-30 2.8 Landscape Design Approach 31 2.9 Photomontages 32 2.10 Materials Pallet 34-36 3.0 Tŷ Fodol Tunnel Headhouse and CSEC 37-63 3.1 Introduction 37 3.2 Regional Context 38 3.3 Strategic Landscape Context 39 3.4 Landscape Designations 41 3.5 Sensitive Visual and Cultural Heritage Receptors 43 3.6 Site and Wider Context Analysis 44 3.7 Vision, Design Options & Principles - Tŷ Fodol 50 3.7.1 Vision and Design Approach 50 3.7.2 Tŷ Fodol Site Building Form Preferred Option and Key Design Principles 52 3.7.3-3.7.6 Tŷ Fodol Building Form Initial Options 54-57 3.8 Landscape Design Approach 58 3.9 Photomontages 59 3.10 Materials Pallet 61-63 4.0 Pentir, Gwynedd 64-69 4.1 Site analysis 64 4.2 Pentir 400kV Substation Technical Design 65 4.3 Landscape Design Approach 69 5.0 Conclusion 70 Tunnel Head House Design Guide Document 7.19 4 1.0 Introduction 1.1 BACKGROUND TO THE PROJECT National Grid operates the electricity transmission system in Great Britain and owns the system in local context. It should be read in conjunction with other documents being submitted as part of the DCO England and Wales. The system operates at 400 kV and 275 kV, connecting electricity generators to application. substations where the higher voltages are transformed to lower voltages, enabling the power to be distributed to homes and businesses by the Distribution Network Operators. This Design Guide has helped to inform the proposed parameters within which the final design for the Tunnel Head Houses at Braint and Tŷ Fodol would need to comply, as defined in the draft Development National Grid has a statutory duty to promote competition in the supply of electricity and is obliged Consent Order for the North Wales Connection Project. This Guide will also inform the final detailed to offer a connection to the system to anyone who applies for a connection. Horizon Nuclear Power architectural form and treatment for the Head Houses, together with the landscape treatment at the two (HNP) has applied to National Grid to connect their proposed new nuclear power station to the tunnel compound sites and in the vicinity of Pentir Substation. The design guide sets out the design national system at Wylfa, Anglesey (Wylfa Newydd). The proposed power station would be within a concepts for each of the sites exploring ideas, approaches and materials that reflect the individual nature site already identified for this type of development in the UK government’s National Policy Statement of each of the sites. Contents will be developed further at detailed design stage based on the design (NPS) EN-6 ‘Nuclear Power Generation’. principles established in this document. The detailed design will be developed with full compliance of the current health and safety regulations and in accordance with CDM regulations. National Grid owns and operates an existing substation at Wylfa, which the proposed Wylfa Newydd power station would connect to. This substation is connected to the main transmission system The sites included within this Design Guide are: on the mainland in North Wales by a 400 kV overhead electricity line, connecting at the existing • Braint Tunnel Headhouse and CSEC; National Grid substation at Pentir, in Gwynedd. To provide reliable electricity supplies, National Grid • Tŷ Fodol Tunnel Headhouse and CSEC; and cannot allow more than 1,800 mega-watts (MW) of power generation to be connected by any single overhead line. As the HNP proposal would have a total output of 2,940 MW, a second connection is • Pentir Substation. required between Wylfa and the transmission system on the mainland.

The Preferred Route Corridor Selection Report (Document 9.2) stated: The large number and concentration of sensitive sites on both shores of the Menai Strait was acknowledged. Given the nature of the landscape and the importance of these sites an overhead line crossing of Anglesey AONB and the Menai Strait would result in significant adverse landscape and visual effects. The Report went on to conclude that: The significant economic cost of using cables instead of overhead lines to cross the Menai Strait would be considered appropriate when set against the significant environmental effects of an overhead line option. Further work would be required at the detailed design stage to confirm the BRAINT TUNNEL TŶ FODOL TUNNEL preferred SEC locations, crossing location and construction methodology for the Menai Strait HEADHOUSE AND HEADHOUSE AND crossing and link to Pentir Substation. CSEC CSEC

Following a detailed appraisal of the options available for crossing the Anglesey AONB and the Limit of deviation Menai Strait National Grid concluded that the most appropriate means of achieving the crossing was Tunnel Head House Locations and tunnel alignment Contains Ordnance Survey data © Crown through the installation of cables in a new deep tunnel. This conclusion is explained in more detail in copyright and database right 100024241(2018) National Grid’s published ‘Menai Strait Crossing Report’ (Document 9.6).

Two sites on either side of the Menai Strait have been identified as locations for Tunnel Head Houses (THH): Braint on the Anglesey side and Tŷ Fodol on the Gwynedd side. This Design Guide describes the context analysis carried out around both these sites. This document explains the various design approaches that have been considered for the Tunnel Head Houses and the surrounding landscaping and presents a preferred design approach that takes account of the site’s

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1.2 PURPOSE AND STRUCTURE OF THE REPORT In May 2017, a series of stakeholder engagement meetings were held with the Isle of Anglesey County Council and Gwynedd Council to discuss the potential design approaches for the proposed tunnel head houses at the Anglesey and Gwynedd tunnel shaft sites. Subsequently National Grid has agreed that a Design Guide presenting overall site and context analysis followed by potential design approaches, colour and materials palettes should be presented as part of the DCO application to provide a clearer understanding of the likely final form for these elements of the proposed development.This Design Guide considers the immediate site contexts as well as wider landscape character. It presents site specific design approaches to the tunnel head house buildings and describes the associated landscape treatments. Objectives set out in the National Policy Statement (NPS) EN-1 and EN-5 have been addressed. Relevant Landscape Character Areas and LANDMAP visual and sensory aspect areas, as well as the strategic contextual landscape issues have been considered.

Braint Site, Anglesey This Design Guide supplements the North Wales Connection Project Design and Access Statement (DAS) (Document 7.16). It relates to the following sites identified as part of the North Wales Connection Project: • Braint Tunnel Headhouse and CSEC; • Tŷ Fodol Tunnel Headhouse and CSEC; and • Pentir Substation.

This Design Guide focuses on the proposed tunnel head houses on the Braint and Tŷ Fodol sites and technical design and landscape treatments for the Pentir Substation site. While this document focuses on the site-specific infrastructure listed above, this does not change National Grid’s commitment to good design, as set out in Design and Access Statement (Document 7.16) in relation to all aspects of the North Wales Connection (NWC) Project.

The primary purpose of this document is to provide a framework of design principles within Tŷ Fodol Site, Gwynedd which National Grid will develop detailed design proposals for the tunnel head houses associated with the NWC Project.

The Design Guide includes: • design Context including National Policy Statement (NPS) EN-1 and EN-5; • a summary of the initial stakeholder engagement on the general design approach that was favoured; • landscape context analysis, design vision, built form design approaches, landscape design approaches, materials palettes and design examples for the Braint and Tŷ Fodol sites; and • technical design and landscape design approach for the Pentir Site.

Existing Pentir Substation

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1.3 PROPOSED INFRASTRUCTURE

Overhead line terminates at The new 400 kV connection would comprise the following: • Tunnel Head Houses: Tunnel head houses would be required pylon and ‘down-droppers’ • Overhead Line approaches to the tunnel compounds: The key on top of the shaft cover slabs to provide direct access into the connect to steel gantry components of an overhead line are as follows: shafts and tunnel for inspection and maintenance. The head -- Pylons: Steel lattice structures, which typically would be house also contains all necessary ventilation equipment and utilities. Typically equipment inside the head house, shaft and We will use landscape 52.5 m in height, and spaced approximately 360 m apart. and planting to help On Anglesey National Grid proposes that the three pylons tunnel would comprise: limit visual impact closest to the site would be low height pylons to reduce -- lighting systems; effects upon more distant views. These are typically around -- heating and air conditioning units; 35 m in height, but wider than more conventional pylons. -- radio systems (for personnel to communicate with each Within Gwynedd the first pylon from the site is proposed to other when in the tunnel during construction and over be low height; operational life of the asset); -- Earth Wire: The highest most line connecting the pylons -- stairwell ventilation (required to maintain safe and clean air and connected to the ground at every pylons in order for personnel to enter the tunnel via the shaft); to protect the overhead line and towers during lightning -- person and goods lift (capable of taking personnel and strikes; equipment into the tunnel); -- system ventilation (needed primarily to maintain a correct -- Conductor: Wire strung between pylons, used for Security fence transmitting electricity; temperature in the shaft and tunnel to ensure that the approx 2.8m high cables do not overheat. It can be natural air flow backed up -- Crossarm: Arms of the pylon that carry the wires and keep Steel gantry supports them separated; and with mechanical fans if required); ‘down-droppers’ -- gas monitors (to ensure tunnel is free from gas ingress and connection to -- Insulator: Holds the conductors to the pylon arms and underground cable sealing Surge diverters provide electrical before workers persons enter); ends provides electrical clearance from the ground and tower protection for underground cables -- Distributed Temperature System (DTS) (to measure the structure. National Grid temperature of a core/cable. This is part of the overall Schematic of Typical Sealing End Compound • Cable Sealing End Compounds: A Cable Sealing End Compound system design and works in conjunction with the system (CSEC) is required when an overhead line changes to an ventilation); underground cable or vice versa. CSECs are secure sites -- pumped drainage (to collect and pump out ground water in surrounded by a palisade fence where the overhead conductors the tunnel and shaft); are connected to the ends of buried cables which are brought -- generators (maybe permanent or temporary) (a tunnel vertically upwards out of the ground; requires a power supply, and a backup system should this • Underground Cables: There are several methods for installing supply fail. Generators can either be brought to site in the underground cables. The preferred technique, due to significantly event of a failure or left in situ); and lower installation costs, is laying underground cables in open cut -- tunnel inspection vehicle (a vehicle used travel along a trenches (or directly on the seabed for marine crossings); tunnel for the purpose of inspection of the cables and • Anglesey AONB and Menai Crossing: A number of techniques carrying equipment to point of any cable or joint failure). have been considered for crossing the Menai Strait by the use • This Design Guide is mainly focused on the design approaches, of new National Grid infrastructure. The proposal to cross the design principles, material pallets, colours and design treatments Menai, is a tunnel; of the Tunnel Head Houses and their interface elements. The technical details of all of the infrastructure are described in other associated documents. National Grid Example of a Tunnel Head House under construction

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The development of the design approaches outlined in this cost effective designs are available. Design Guide was based on several considerations regarding the National Grid appreciates that stakeholders and communities need functional requirements for the tunnel head houses in terms of both to be reassured about the final scale and form of the building, engineering as well as design and contextual issues. Some key especially given the rural, sensitive settings that these tunnel head considerations in the design development discussions included: houses would be located in. Hence there is a hierarchy of control • the industrial fans for cooling and ventilation are key features in measures that are being proposed which include: the THHs. They do tend to determine the highest point of the built • the Parameter Plans impose absolute restrictions on the building form. Generally air is expelled at the highest point of any tunnel, location and scale. They determine zones within which the tunnel working with rather than against the natural direction of airflow. head houses would need to be sited and suggest maximum In this case the highest point of the tunnel would be at Tŷ Fodol, heights and maximum volume for the buildings, which are specific and therefore it is proposed that air is extracted using larger fan to the functional requirements at each of the two sites. Maximum units located at this end of the tunnel. In Braint, the height is kept footprint dimensions in terms of length and width have not been at a minimum as high ventilation fans are not required at this stipulated as it is believed that a modest increase in building end of the tunnel. The Tŷ Fodol built form needs to be higher to footprint (albeit within the location parameters imposed) might accommodate bigger fan units; allow some elements of the building to be reduced in height, and • the THHs also need to accommodate associated welfare facilities potentially afford opportunities to further break up the overall and some of the control rooms which could be lower in height; and massing; and • vehicle access points for maintenance and plant replacement, • Requirement 4 of the draft DCO states: Unless otherwise agreed shaft access gantry cranes etc. are other key design with the relevant planning authority, the above ground elements considerations. The design approaches include placing such of the authorised development comprised in Works No 8 (Braint features along less sensitive interfaces. Tunnel Head House and Cable Sealing End Compound to Tŷ Fodol Tunnel Head House and Cable Sealing End Compound) The functional requirements have influenced the overall design must be carried out in general accordance with the Key Design approaches that are outlined in later sections of this document Principles set out in the “Tunnel Head House Design Guide”. in terms of determining internal heights, placement of single and double storey areas, minimum likely footprint dimensions, minimum Hence the Tunnel Head House Design Guide as well as the height requirements etc. There is often limited design flexibility due Parameters Plans combine to establish and impose the key design to the fact that functional requirements of the complex infrastructure principles for the proposed tunnel head houses. that these tunnel head houses enclose are often determined by mechanical and safety specifications. However, the Design Guide presents design approaches that take into account these restrictive functional design requirements but balances them with the contextual setting and local sensitivities. The key aim is to balance the functional requirements against the need to limit apparent scale of the buildings in rural, generally undeveloped, locations.

National Grid is not able to submit a detailed fixed design for the tunnel head houses at this stage. This is because a final contractor has not been appointed at this early design stage. Hence, there is a need to retain flexibility to accommodate design innovation and allow a range of design solutions to be put forward, ensuring high quality,

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1.4 DESIGN CONTEXT

EN-1 EN-5

Section 4.5 of Overarching National Policy Statement for Energy (EN-1) sets out the Section 2.5 of National Policy Statement for Electricity Networks Infrastructure (EN-5) states criteria for “good design” for energy infrastructure, whilst recognising the importance of the that proposals for electricity networks infrastructure should demonstrate good design in their functional requirements and physical constraints which apply to infrastructure projects of this approach to mitigating the potential adverse impacts which can be associated with overhead nature. lines, particularly those relating to: • landscape and visual; EN-1 states that applying “good design” to energy projects should produce sustainable • biodiversity and geological conservation; infrastructure that is sensitive to place, efficient in the use of natural resources and energy • noise and vibration; and used in it’s construction and operation, matched by an appearance that demonstrates good aesthetic as far as possible. EN-1 acknowledges, however that the nature of much • electric magnetic fields (EMFs). energy infrastructure development will often limit the extent to which it can contribute to the enhancement of the quality of the area. EN-5 paragraph 2.8.2 states that new substations, sealing end compounds and other above ground installations that form connection, switching and voltage transformation points on the electricity networks can also give rise to landscape and visual impacts. In considering applications, EN-1 states that the Secretary of State should take into account In accordance with EN-5 paragraph 2.8.10 this Design Guide sets out the opportunities for the ultimate purpose of the infrastructure and bear in mind the operational, safety and mitigating potential adverse landscape and visual impacts. security requirements that the design has to satisfy.

EN-5 paragraph 2.8.11 identifies specific measures that might be used. This Design Guide explains how the Proposed Development has taken into account functionality (including fitness for purpose and sustainability) and aesthetics (including This Design Guide identifies site-specific mitigation comprising peripheral planting and contribution to the local context and quality of the area) in the design approach to the tunnel sensitive re-profiling of landforms in views into the THHs and Pentir substation in order to help head houses. screen or soften the visual effects of the sites. It also provides built form massing and design options that show design responses to limit potential effects on views.

This Design Guide explains the studies, principles and design approaches that have influenced the siting, building design (including form, colour and materials), and landscape design approach for the tunnel head houses to ensure they respond to the site context and are attractive, durable and adaptable. This has included consideration of existing landscape character, landform and vegetation in order to help mitigate adverse impacts and other effects.

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DOCUMENT 7.16

Design and Access Statement

National Grid (North Wales Connection Project)

Regulation 5(2)(q) of the Infrastructure Planning (Applications: Prescribed Forms and Procedure) Regulations 2009

Application Reference EN020015 September 2018

National Grid’s Substation Siting Guidelines The North Wales Connection Project Design and Access Statement

The Substation Siting Guidelines set out National Grid’s approach to substation siting and Section 3 of the Design and Access Statement (DAS, Document 7.16) considers the policy context design in the context of National Grid’s duties under Schedule 9 of the Electricity Act to have for the consideration of design issues, focusing on EN-1 and EN-5. regard to amenity considerations. Substation Siting Guidelines were applied in determining the location of proposed site-specific infrastructure comprising substation and CSE Local Planning Policy compounds and aim to: The Joint Local Development Plan (JLDP) for Anglesey and Gwynedd was adopted in July 2017 • limit environmental effects; (Ref 19) and is the planning policy document for Anglesey and Gwynedd (excluding that area • seek to avoid internationally and nationally designated areas of the highest value; within the Snowdonia National Park Planning Authority). It contains the key policies and land use • protect areas of local amenity value, important existing habitats and landscape features; allocations that will facilitate the Plan area’s development up to 2026. • take advantage of screening provided by landform and existing features and utilise site layout and levels to minimise intrusion into surrounding areas; As set out in NPS EN-1 (para 4.1.5), Local Development Plans are one of the matters which the • consider land-use effects of the proposal when planning siting; decision-maker may consider to be important and relevant. • consider options available for terminal pylons, equipment, buildings and ancillary development appropriate to individual locations, seeking to keep effects to a reasonably The Proposed Development has therefore also been considered against JLDP for Anglesey and practical minimum; Gwynedd (2017) (Ref 19). The compliance of the Proposed Development as a whole with relevant • use space effectively to limit the development area and provide appropriate mitigation to planning policy is considered in the Planning Statement (Document 7.14). minimise adverse effects on land use and rights of way; • ensure the design of an access road, perimeter fencing, earthworks, planting and The development plan policies do not provide criteria for determining the acceptability of ancillary development forms an integral part of the site layout and design to fit in with the NSIPs, and in their detail they are not always directly applicable to linear infrastructure projects. surroundings; Notwithstanding this the overarching principles of responding to place, minimising adverse impacts • keep high voltage line entries visually separate from low voltage lines and other overhead and enhancing the local environment have been objectives for the Proposed Development. lines to avoid a confusing appearance; and • ensure the inter-relationship between pylons and substation structures and background and foreground features are studied to reduce the prominence of structures from main viewpoints.

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1.5 INITIAL STAKEHOLDER ENGAGEMENT At the initial stakeholder engagement meeting National Grid The examples in the adjoining photos are drawn from existing National Grid substation and tunnel sites in the case of the ‘Standard presented three suggested design approaches for the tunnel Industrial’ and ‘Architectural Statement’ examples. These photos seek to illustrate how the first two design approaches are significantly head house structures: different from the ‘Rural Architecture’ approach that aims to reflect the local rural vernacular in the vicinity of the two sites in North Wales to • Standard Industrial approach; draw design inspiration for the tunnel head houses designs in either site based on their distinct local characteristics. • Architectural Statement; and • Rural Architecture Approach.

The general consensus from discussions with officers working for both local authorities was that the Rural Architecture style would be more appropriate in the given contexts of both the Braint and Tŷ Fodol sites. However, it was suggested that they have distinctly different landscape and characteristics, which need to be considered in the design development. Some key differences include: • the Braint landscape character is considered as being more planned and is heavily influenced by the estate architecture found in the surrounding context; and • the Tŷ Fodol context is characterised by individual farmsteads, with a more diverse range of agricultural built form, that have extended gradually over time. Further characteristics of these two sites have been explored in ensuing sections of this report. National Grid Standard Industrial approach National Grid Architectural Statement

North Wales Connection Project Tunnel Head House Design Guide Document 7.19 11

Examples of local agricultural buildings that has influenced the RuralArchitecture Approach

North Wales Connection Project Tunnel Head House Design Guide Document 7.19 12

THE NATIONAL GRID (NORTH WALES CONNECTION PROJECT) ORDER GORCHYMYN NATIONAL GRID (PROSIECT CYSYLLTIAD GOGLEDD CYMRU) DESIGN PLAN: PARAMETER PLAN FOR BRAINT TUNNEL HEAD HOUSE AND CYNLLUN DYLUNIO: CYNLLUN O'R PARAMEDR AR GYFER PRIF DŶ TWNNEL AFON BRAINT 2.0 Braint Tunnel Headhouse and CSEC CABLE SEALING END COMPOUND A'R COMPOWND SY'N SELIO PENNAU CEBLAU REGULATION 5(2)(o) RHEOLIAD 5(2)(o) SHEET 1 OF 8 DALEN 1 O 8 2.1 INTRODUCTION ISLE OF ANGLESEY COUNTY COUNCIL CYNGOR SIR YNYS MÔN ANGLESEY

The Braint site is located within pasture land in order to understand the local vernacular GWYNEDD between properties known as Rhosbothan (500 m), architecture and landscape further; Llwyn-ogan (200 m) and Tyddyn Fadog (340 m). • it was agreed that although the area is Legend / Allwedd

TEMPORARY CONSTRUCTION The general local character of the area is rural influenced by estate style architecture, COMPOUND AREA INDICATIVE AREA WITHIN WHICH POSSIBLE LANDSCAPING / MITIGATION pasture land with agricultural plots bordered by this shouldn’t be slavishly replicated for WILL TAKE PLACE

ZONE WITHIN WHICH FULL small blocks of woodland, spinneys and coverts the operational compound, but it is a good LINE TENSION GANTRIES AND CABLE SEALING END WILL BE LOCATED

associated with the local estates. design cue that needs to be developed in a ZONE WITHIN WHICH TUNNEL HEAD HOUSE WILL BE contemporary manner; LOCATED ZONE WITHIN WHICH PERMANENT ACCESS ROAD Initial Stakeholder Engagement • the Braint site is visible from a number of WILL BE LOCATED AREA WITHIN WHICH TUNNEL HEAD HOUSE AND CABLE viewpoints, hence careful consideration should SEALING END COMPOUND Some of the key themes that emerged from the WILL BE LOCATED

ILLUSTRATIVE SIZE OF THE be given to views to and from Bryn Celli Ddu TUNNEL HEAD HOUSE AND initial stakeholder engagement with the officers CABLE SEALING END Schedule Monument, the community of Star and COMPOUND from Isle of Anglesey County Council were as ILLUSTRATIVE LOCATION OF THE TUNNEL HEAD HOUSE (MAXIMUM DIMENSIONS A4080; MEASURED EXTERNALLY follows: (H) 8m VOLUME 4,350m³)

ILLUSTRATIVE ROUTE OF • the site is visible from the community of Star, PERMANENT ACCESS ROAD • there was a general preference within the three THE NATIONAL GRID (NORTH WALES CONNECTION PROJECT) ORDER GORCHYMYN NATIONAL GRID (PROSIECT CYSYLLTIAD GOGLEDD CYMRU) 1. This drawing is scaled at paper size A1, therefore any prints taken at DESIGN PLAN: PARAMETER PLAN FOR BRAINT TUNNEL HEAD HOUSE AND CYNLLUN DYLUNIO: CYNLLUN O'R PARAMEDR AR GYFER PRIF DŶ TWNNEL AFON BRAINT smaller sizes will affect accuracy of the measurement units and should not against a background of existing land form; be scaled against. THE NATIONAL GRIDCABLE (NORTH SEALING WALES END CONNECTION COMPOUND PROJECT) ORDER GORCHYMYN NATIONALA'R COMPOWND GRID (PROSIECT SY'N SELIO CYSYLLTIAD PENNAU CEBLAU GOGLEDD CYMRU) suggested design approaches for the building DESIGN PLAN: PARAMETERREGULATION PLAN FOR BRAINT 5(2)(o) TUNNEL HEAD HOUSE AND CYNLLUN DYLUNIO: CYNLLUN O'R PARAMEDRRHEOLIAD AR5(2)(o) GYFER PRIF DŶ TWNNEL AFON BRAINT CABLE SEALINGSHEET END 1 OF COMPOUND 8 A'R COMPOWND DALENSY'N SELIO 1 O 8 PENNAU CEBLAU • a stark,ISLE OF ANGLESEYREGULATION modern COUNTY 5(2)(o) COUNCIL design approach would be CYNGORRHEOLIAD SIR YNYS 5(2)(o) MÔN 0 30 60 Metres design to be reflective of rural architectural SHEET 1 OF 8 DALEN 1 O 8 unlikelyISLE OF ANGLESEY to COUNTY be COUNCIL appropriate in this area. A low- CYNGOR SIR YNYS MÔN ANGLESEY character, but with due regard to the estate style ANGLESEY architecture and character found in this part key built form with natural materials that might

more comfortably be accommodated within the A FOR DCO SUBMISSION KJ SR RP of Anglesey. The preference was for a design GWYNEDD

GWYNEDD landscape might be more appropriate; THE NATIONAL GRID approach that doesn’t stand out, but pays due (NORTH WALES CONNECTION PROJECT) ORDER DESIGN PLAN: PARAMETER PLAN FOR BRAINT TUNNEL HEAD HOUSE AND CABLE SEALING END COMPOUND REGULATION 5(2)(o) regard to the existing, and often different styles • in terms of building materials, it was suggested SHEET 1 OF 8 Legend / Allwedd ISLE OF ANGLESEY COUNTY COUNCIL

THE NATIONAL GRID (NORTH WALES CONNECTION PROJECT) ORDER GORCHYMYN NATIONAL GRID (PROSIECT CYSYLLTIAD GOGLEDD CYMRU) GORCHYMYN NATIONAL GRID Legend / AllweddTEMPORARY CONSTRUCTION (PROSIECT CYSYLLTIAD GOGLEDD CYMRU) evident in the localDESIGNTHE NATIONAL PLAN:vernacular PARAMETER GRID (NORTH PLAN WALES FOR BRAINT CONNECTIONwhich TUNNEL PROJECT) HEAD are HOUSE ORDER ANDheavily thatCYNLLUN stoneGORCHYMYN DYLUNIO: shouldCYNLLUN NATIONAL O'R GRID PARAMEDR (PROSIECT be AR CYSYLLTIADconsideredGYFER PRIF GOGLEDDDŶ TWNNEL CYMRU) AFON BRAINTbut rendered CYNLLUN DYLUNIO: CYNLLUN O'R PARAMEDR AR GYFER PRIF COMPOUND AREA CABLE SEALING END COMPOUND A'R COMPOWND SY'N SELIO PENNAU CEBLAU DŶ TWNNEL AFON BRAINT A'R COMPOWND SY'N SELIO DESIGNTHE NATIONAL PLAN: PARAMETER GRID (NORTH PLAN WALES FOR BRAINT CONNECTION TUNNEL PROJECT) HEAD HOUSE ORDER AND CYNLLUNGORCHYMYN DYLUNIO: CYNLLUN NATIONAL O'R GRID PARAMEDR (PROSIECT AR CYSYLLTIADGYFER PRIF GOGLEDDDŶ TWNNEL CYMRU) AFON BRAINT PENNAU CEBLAU CABLE REGULATIONSEALING END 5(2)(o) COMPOUND A'R COMPOWNDRHEOLIAD SY'N SELIO 5(2)(o) PENNAU CEBLAU TEMPORARY CONSTRUCTION RHEOLIAD 5(2)(o) DESIGN PLAN: PARAMETER PLAN FOR BRAINT TUNNEL HEAD HOUSE AND CYNLLUN DYLUNIO: CYNLLUN O'R PARAMEDR AR GYFER PRIF DŶ TWNNEL AFON BRAINT INDICATIVECOMPOUND AREA AREA WITHIN DALEN 1 O 8 REGULATIONSHEET 1 OF 5(2)(o) 8 DALEN 1 O 8 WHICH POSSIBLE CYNGOR SIR YNYS MÔN influenced by the estateCABLE architectureSEALING END COMPOUND found at finishes wereA'R COMPOWND unlikelyRHEOLIAD SY'N SELIO 5(2)(o) PENNAU to CEBLAU be appropriate. ISLE OF ANGLESEYSHEET 1COUNTY OF 8 COUNCIL LANDSCAPING / MITIGATION REGULATION 5(2)(o) CYNGORRHEOLIADDALEN SIR 1YNYS 5(2)(o)O 8 MÔN INDICATIVEWILL TAKE PLACE AREA WITHIN ISLE OF ANGLESEYSHEET 1COUNTY OF 8 COUNCIL CYNGOR SIR YNYS MÔN WHICH POSSIBLE DALEN 1 O 8 ANGLESEY LANDSCAPING / MITIGATION the Plas Newydd and PlasISLE OF ANGLESEY Coch COUNTY COUNCILestates; Similarly, CortenCYNGOR steel SIR YNYS MÔN was not considered ZONEWILL TAKE WITHIN PLACE WHICH FULL Application Number / Rhif y Cais ANGLESEY LINE TENSION GANTRIES EN020015 AND CABLE SEALING END N National Grid Drawing Reference / Cyfeirnod Lluniad National Grid ANGLESEY ZONE WITHIN WHICH FULL WILL BE LOCATED DCO_DE/PS/09_01 appropriate; LINE TENSION GANTRIES • whilst it has been suggested that cues might AND CABLE SEALING END ZONEWILL BE WITHIN LOCATED WHICH TUNNEL 1:1000 A1 SHEET 1 OF 8 A HEAD HOUSE WILL BE LOCATED be taken from Horizon Nuclear Power’s • more traditional roof forms would be better Braint Tunnel Headhouse and CSEC Outline PlanZONE WITHIN for WHICH DCOTUNNEL application Contains Ordnance Survey data © HEAD HOUSE WILL BE GWYNEDD LOCATED ZONE WITHIN WHICH GWYNEDD PERMANENT ACCESS ROAD Crown copyright and database right design approach to the buildings on the Wylfa suited in this locality rather than wavy or organic WILL BE LOCATED GWYNEDD ZONE WITHIN WHICH PERMANENT ACCESS ROAD 100024241(2018) WILL BE LOCATED Newydd site, it is considered that the lack of roof forms; AREA WITHIN WHICH TUNNEL HEAD HOUSE AND CABLE LEGEND SEALING END COMPOUND Legend / Allwedd WILLAREA BE WITHIN LOCATED WHICH TUNNEL HEAD HOUSE AND CABLE any visual relationship between the two sites Legend / Allwedd SEALING END COMPOUND • extensive mounding would be alien to ILLUSTRATIVEWILL BE LOCATED SIZE OF THE Legend / AllweddTEMPORARY CONSTRUCTION TUNNEL HEAD HOUSE AND COMPOUNDTemporary AREA construction compound area CABLE SEALING END TEMPORARY CONSTRUCTION Illustrative size of the tunnel head house ILLUSTRATIVECOMPOUND SIZE OF THE COMPOUND AREA (given the intervening distance) and their TUNNELand HEAD cable HOUSE AND sealing end compound INDICATIVETEMPORARY AREA CONSTRUCTION WITHIN this landscape and would very likely be CABLE SEALING END COMPOUNDWHICH POSSIBLE AREA Indicative area within which possible COMPOUND INDICATIVELANDSCAPING AREA / MITIGATION WITHIN ILLUSTRATIVE LOCATION OF WHICH POSSIBLE WILL TAKE PLACE THE TUNNEL HEAD HOUSE INDICATIVE AREA WITHIN differing landscape characters would make this LANDSCAPINGLandscaping / MITIGATION / Mitigation would take place (MAXIMUMIllustrative DIMENSIONS location of the tunnel head WILLWHICH TAKE POSSIBLE PLACE inappropriate; ILLUSTRATIVEMEASURED EXTERNALLY LOCATION OF LANDSCAPING / MITIGATION ZONE WITHIN WHICH FULL (H)THE 8m TUNNEL VOLUME HEAD 4,350m³) HOUSE WILL TAKE PLACE house (Maximum dimensions measured LINE TENSION GANTRIES (MAXIMUM DIMENSIONS ZONEAND CABLE WITHIN SEALING WHICH FULLEND inappropriate; LINEZone TENSION GANTRIESwithin which full Line tension MEASUREDexternally EXTERNALLY (H) 8 m volume 4,350 m³) WILL BE LOCATED (H) 8m VOLUME 4,350m³) ZONEAND CABLE WITHIN SEALING WHICH FULLEND ILLUSTRATIVE ROUTE OF • the access design should not overuse tarmac LINEWILLgantries TENSIONBE LOCATED GANTRIES and cable sealing end would PERMANENT ACCESS ROAD AND CABLE SEALING END ZONE WITHIN WHICH TUNNEL WILL BE LOCATED HEADbe HOUSE located WILL BE ILLUSTRATIVE ROUTE OF ZONE WITHIN WHICH TUNNEL PERMANENTIllustrative ACCESS ROAD route of permanent • the landscape in this part of Anglesey differs LOCATED 1. This drawing is scaled at paper size A1, therefore any prints taken at HEAD HOUSE WILL BE or other visually stark materials in this rural smaller sizes will affect accuracy of the measurement units and should not LOCATEDZONE WITHIN WHICH TUNNEL be scaled against. access road HEADZone HOUSE WILL within BE which tunnel Head house LOCATED 1. This drawing is scaled at paper size A1, therefore any prints taken at ZONE WITHIN WHICH smaller sizes will affect accuracy of the measurement units and should not greatly from that in Gwynedd, in that the would be located be scaled against. environment. A mosaic of different materials and PERMANENT ACCESS ROAD WILLZONE BE WITHIN LOCATED WHICH PERMANENT ACCESS ROAD 0 30 60 WILLZONEZone BE WITHIN LOCATED WHICH within which permanent access Metres landscape is significantly more planned and PERMANENT ACCESS ROAD surfaces, reinforced grass or coloured aggregate AREAWILL BE WITHIN LOCATED WHICH TUNNEL 0 30 60 road would be located Metres HEAD HOUSE AND CABLE SEALINGAREA WITHIN END WHICHCOMPOUND TUNNEL HEADWILL BE HOUSE LOCATED AND CABLE is based around and heavily influenced by SEALINGAREA WITHIN END WHICHCOMPOUND TUNNEL with complementary landscape treatments to HEADWILLArea BE HOUSE LOCATED ANDwithin CABLE which tunnel head house ILLUSTRATIVESEALING END COMPOUNDSIZE OF THE TUNNELWILLand BE LOCATEDHEAD cable HOUSE AND sealing end compound would ILLUSTRATIVECABLE SEALING SIZE END OF THE estate architecture and therefore the building TUNNEL HEAD HOUSE AND COMPOUND screen access routes should be considered; and ILLUSTRATIVEbe located SIZE OF THE CABLE SEALING END COMPOUNDTUNNEL HEAD HOUSE AND CABLE SEALING END A FOR DCO SUBMISSION KJ SR RP form, materials and colour palette for the Braint ILLUSTRATIVECOMPOUND LOCATION OF THE TUNNEL HEAD HOUSE • local geology and earth colours to be considered ILLUSTRATIVE(MAXIMUM DIMENSIONS LOCATION OF A FOR DCO SUBMISSION KJ SR RP MEASUREDTHE TUNNEL EXTERNALLY HEAD HOUSE THE NATIONAL GRID ILLUSTRATIVE LOCATION OF (H)(MAXIMUM 8m VOLUME DIMENSIONS 4,350m³) (NORTH WALES CONNECTION PROJECT) ORDER operational compound should be different to the MEASUREDTHE TUNNEL EXTERNALLY HEAD HOUSE DESIGN PLAN: PARAMETER PLAN FOR BRAINT TUNNEL HEAD HOUSE AND (H)(MAXIMUM 8m VOLUME DIMENSIONS 4,350m³) THE NATIONAL GRID CABLE SEALING END COMPOUND but existing built forms, both historic and MEASURED EXTERNALLY (NORTH WALES CONNECTION PROJECT) ORDER REGULATION 5(2)(o) ILLUSTRATIVE ROUTE OF DESIGN PLAN: PARAMETER PLAN (H) 8m VOLUME 4,350m³) SHEET 1 OF 8 FOR BRAINT TUNNEL HEAD HOUSE AND PERMANENT ACCESS ROAD ISLE OF ANGLESEY COUNTY COUNCIL Tŷ Fodol operational compound; ILLUSTRATIVE ROUTE OF CABLE SEALING END COMPOUND PERMANENT ACCESS ROAD REGULATION 5(2)(o) SHEET 1 OF 8 new, were often imported and hence do not ILLUSTRATIVE ROUTE OF GORCHYMYN NATIONAL GRID ISLE OF ANGLESEY COUNTY COUNCIL 1. This drawing is scaled at paperPERMANENT size A1, therefore ACCESSany prints taken ROAD at (PROSIECT CYSYLLTIAD GOGLEDD CYMRU) smaller sizes will affect accuracy of the measurement units and should not CYNLLUN DYLUNIO: CYNLLUN O'R PARAMEDR AR GYFER PRIF be scaled against. 1. This drawing is scaled at paper size A1, therefore any prints taken at DŶ TWNNEL AFON BRAINT A'R COMPOWND SY'N SELIO GORCHYMYN NATIONAL GRID • a Local Characterisation study was suggested smaller sizes will affect accuracy of the measurement units and should not PENNAU CEBLAU be scaled against. (PROSIECT CYSYLLTIAD GOGLEDD CYMRU) necessarily reflect the local geology. 1. This drawing is scaled at paper size A1, therefore any prints taken at RHEOLIAD 5(2)(o) CYNLLUN DYLUNIO: CYNLLUN O'R PARAMEDR AR GYFER PRIF smaller sizes will affect accuracy of the measurement units and should not DALEN 1 O 8 DŶ TWNNEL AFON BRAINT A'R COMPOWND SY'N SELIO be scaled against. CYNGOR SIR YNYS MÔN PENNAU CEBLAU 0 30 60 RHEOLIAD 5(2)(o) Metres DALEN 1 O 8 0 30 60 CYNGOR SIR YNYS MÔN Metres 0 30 60 Application Number / Rhif y Cais Metres EN020015

National Grid Drawing Reference / Cyfeirnod Lluniad National Grid Application Number / Rhif y Cais DCO_DE/PS/09_01 EN020015

National Grid Drawing Reference / Cyfeirnod Lluniad National Grid 1:1000 A1DCO_DE/PS/09_01SHEET 1 OF 8 A

1:1000 A1 SHEET 1 OF 8 A

A FOR DCO SUBMISSION KJ SR RP

A FOR DCO SUBMISSION KJ SR RP

A FOR DCO SUBMISSION KJ SR RP THE NATIONAL GRID (NORTH WALES CONNECTION PROJECT) ORDER North Wales Connection Project DESIGNTHE PLAN: NATIONAL PARAMETER GRID PLAN (NORTHFOR WALES BRAINT CONNECTION TUNNEL HEAD PROJECT) HOUSE AND ORDER CABLEDESIGNTHE SEALING PLAN: NATIONAL PARAMETER END COMPOUNDGRID PLAN (NORTHFOR WALES BRAINTREGULATION CONNECTION TUNNEL HEAD 5(2)(o) PROJECT) HOUSE AND ORDER CABLEDESIGN SEALING PLAN:SHEET PARAMETER END 1 OF COMPOUND 8 PLAN FORISLE BRAINT OF ANGLESEYREGULATION TUNNEL COUNTY HEAD 5(2)(o) HOUSE COUNCIL AND CABLE SEALINGSHEET END 1 OF COMPOUND 8 ISLE OF ANGLESEYREGULATION COUNTY 5(2)(o) COUNCIL GORCHYMYNSHEET NATIONAL 1 OF 8 GRID (PROSIECTISLE OF ANGLESEY CYSYLLTIAD COUNTY GOGLEDD COUNCIL CYMRU) CYNLLUN DYLUNIO:GORCHYMYN CYNLLUN NATIONALO'R PARAMEDR GRID AR GYFER PRIF DŶ TWNNEL(PROSIECT AFON CYSYLLTIAD BRAINT A'R GOGLEDDCOMPOWND CYMRU) SY'N SELIO CYNLLUN DYLUNIO:GORCHYMYN CYNLLUNPENNAU NATIONALO'R CEBLAU PARAMEDR GRID AR GYFER PRIF DŶ TWNNEL(PROSIECT AFON CYSYLLTIAD BRAINTRHEOLIAD A'R 5(2)(o)GOGLEDDCOMPOWND CYMRU) SY'N SELIO CYNLLUN DYLUNIO: CYNLLUNPENNAUDALEN O'R CEBLAU 1 OPARAMEDR 8 AR GYFER PRIF DŶ TWNNEL AFONCYNGOR BRAINTRHEOLIAD SIR A'R YNYS 5(2)(o) COMPOWND MÔN SY'N SELIO PENNAUDALEN CEBLAU 1 O 8 CYNGORRHEOLIAD SIR YNYS 5(2)(o) MÔN DALEN 1 O 8 CYNGOR SIR YNYS MÔN Application Number / Rhif y Cais EN020015 Application Number / Rhif y Cais National Grid Drawing ReferenceEN020015 / Cyfeirnod Lluniad National Grid Application Number / Rhif y CaisDCO_DE/PS/09_01 National Grid Drawing Reference / Cyfeirnod Lluniad National Grid EN020015 DCO_DE/PS/09_01 National1:1000 Grid Drawing ReferenceA1 / CyfeirnodSHEET Lluniad 1 OF 8National GridA DCO_DE/PS/09_01 1:1000 A1 SHEET 1 OF 8 A

1:1000 A1 SHEET 1 OF 8 A Tunnel Head House Design Guide Document 7.19 13

2.2 REGIONAL CONTEXT

Anglesey

Wales

Anglesey is the largest of the Welsh islands, covering some 720 square kilometres and separated from the mainland by the Menai Strait; a narrow stretch of tidal water approximately 25 km long and about 250 metres wide at its narrowest. The main towns on the island are Llangefni, Holyhead, Amlwch, Benllech, Menai Bridge and Llanfairpwll.

The topography of the island is generally subdued with a rolling, undulating pattern interspersed by harder, rocky outcrops such as Holy Island, Mynydd Parys, Mynydd Bodafon and Mynydd Llwydiarth. The landform generally falls east to west, with a number of low lying areas along the west coast including Aberffraw, Malltraeth Marsh and Newborough Warren. This landform pattern is reflected in the north-east – south-west alignment of water courses. This general character belies a complex, underlying geology and effects of geomorphological processes such as glaciation. The island contains some of the oldest rocks in Wales and Britain as a whole, and these are clearly illustrated in the topography of the island.

In broad terms, inland Anglesey can be described as lowland farmland with relatively sparse tree cover in the north, where there is a more open, rolling and windswept character, which becomes increasingly well treed towards the south; in particular towards the Menai Strait. There are a number of fens and extensive areas of drumlins, especially in the north and west and parkland landscapes are found to the south and east. The island’s rural coastline has been designated an Area of Outstanding Natural Beauty and features many sandy beaches, especially along its eastern and western coast. The northern coastline has dramatic cliffs interspersed with small bays and the southern coast is focussed on the Menai Strait. The Jim Linwood, Flickr Anglesey Coastal Path (which forms part of the Wales Coast Path) is a 200 km path, The Menai Bridge which follows nearly the entire coastline.

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2.3 STRATEGIC LANDSCAPE CONTEXT Leend Leend 1 / Head House raint nglese 1 / Head House raint nglese Braint site, Anglesey Ntion Lndce Crcter Are Ntion Lndce Crcter Are 1 rordir nnglese Coast N 1 rordir nnglese Coast 5km 1 Canolarth dnCentral nglese 1 Canolarth dnCentral nglese ron ron

ln ln

ae TremadogTremadoc aae TremadogTremadoc a

rrinodonia rrinodonia 1 1 7 Drn ConCona7 alle Drn ConCona alle rordir Coln ar GogleddColn and Northern rordir Coln ar GogleddColn and Northern 2 Coastline 2 Coastline 1 8 9 rniau hoshos Hills 1 8 9 rniau hoshos Hills 1 ndd HiraethogDenigh oors 1 ndd HiraethogDenigh oors 1 Drn Drd a langollenlangollen and the Anglesey ale o Dee 1 Drn Drd a langollenlangollen and the ale o Dee 1 ernern 1 ernern 9 National Landscape Character Area: Anglesey Coast 7 9 3 7 The area encompasses all of the coastal areas of the Isle of Anglesey, including the 3 adjacent Holy Island. The north-east to south-west trending geological faults and varying rock types influence the shape and geometry of the coast. Although much of Anglesey is low lying, the higher hills lie in the northern half of the coastal area. The prevailing winds also create a distinctly more exposed south-westerly coast, where well developed dune systems and lagoons run inland. Much of the former estuary of Gwynedd the Afon Cefni has been reclaimed but the resulting coastal levels remain within this character area. Though mainly farmed, the area contains numerous coastal heaths, dunes, and areas of gorse scrub. Together with the island’s two largest woodland

10 plantations, these areas help to distinguish the character from that further inland. A meandering inter-tidal strait separates mainland Anglesey from Holy Island. Arrival on Anglesey10 from mainland Wales is across either of two spectacular bridges at Menai 6 Bridge, which cross the estuary-like Menai Strait around the narrowest point west of the community of Menai Bridge. 6 Views to the distant mountains of Snowdonia create a dramatic south eastern backdrop to 5 much ofAnglesey. Closer to, these mountains become more impressive and engaging, and 6 when viewed across a foreground setting of the Menai Strait around Beaumaris, they 15 4 5 engender a sense of scale and drama. At the other end of the Strait, the extent of the 6 dunes, beaches and Caernarfon Bay provide a spectacular setting for views of the 16Llŷn peninsula. 4 15

11 1 eters Contains ulic sector inormation licensed under the en Goernment icence . The area coincides with Anglesey Coast AONB, along with a number of stretches of 16 Heritage Coast. The island is designated as a Geopark. Beaumaris Castle in the east forms part of a World Heritage Site. 1 eters Contains ulic sector inormation licensed under the en Goernment icence . National Landscape Character Areas

North Wales Connection Project Tunnel Head House Design Guide Document 7.19 15

/ Leend Leend BraintHead House site, Anglesey raint nglese / N Head House raint nglese Gwynedd Lndce Crcter Are Gwynedd Lndce Crcter Are C 1 angor Coastal Plan C 1 angor Coastal Plan LCA 17 LCA 17 C 1 enai Coast C 1 enai Coast C Penisaraun Plateau C Penisaraun Plateau C laneries ethesda C laneries ethesda C Caernaron Coast and Plateau C Caernaron Coast and Plateau Aneey Lndce Crcter Are Aneey Lndce Crcter Are C 11 astern enai trait C 11 astern enai trait LCA C 1 ast Central nglese 1 C 1 ast Central nglese LCA 11 C 1 Western enai trait LCA 1 C 1 Western enai trait C 1 Nirch LCA 11

C 1 on Ceni C 1 Nirch

Anglesey C 17 West Central nglese C 1 on Ceni LCA 15 C 17 West Central nglese LCA 12 LCA 15 A55 LCA 12

Bangor

Gwynedd LCA 16 LCA 1

LCA 1 LCA 16 A55

Landscape Character Area (LCA)12 : East Central AngleseyLCA 2 LCA 13

LCA 2 In 2011 The Isle of Anglesey County Council published a landscape assessment LCA 13 study of the local landscape character areas. The Braint site area falls within the LCA 12 East Central Anglesey, which reflects much of the typical undulating A487 landscape of Anglesey. The majority of the area consists of improved grassland interspersed with scattered areas of semi-natural habitat. In places, hedgerows A4244 and hedgebanksLCA 4 (and cloddiau) form field boundaries, and where rock outcrops exist, stone walls are more typically field boundaries. LCA 4 LCA 2 The underlying geology is varied, with glacial depositsLCA 3in the east and to more mixed intrusive and sedimentary features in the west. Central parts of the LCA LCA 2 LCA 14 are influenced by the A5 trunk road, now superseded by the A55 trunk road, LCA 3 which runs relatively parallel. Impacts of this9 transport 9corridoreters on the landscape Contains ulic sector inormation licensed under the en Goernment icence . are local and varied. Likewise cultural and historic influences vary, which is typical of the island. Settlements vary from nucleated to dispersed patterns. LCA 14 9 9 eters Contains ulic sector inormation licensed under the en Goernment icence . Local Landscape Character Areas Contains Ordnance Survey data © Crown copyright and database right 100024241(2018)

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2.4 LANDSCAPE DESIGNATIONS

The following designated areas have been identified within 5 km of the site

Site boundary - Braint, Anglesey

Site of Special Scientific interest- The most important sites for Wales natural heritage. These are highly protected to safeguard the range,quality and variety of habitats, species and geological features in all parts of Wales. The identified sites are Sgistau Glas Ynys Mon; Cadnant Dingle; Glannau Porthaethwy.

Local Nature Reserve - Coed Cyrnol Nature Reserve is an area of mixed deciduous, broadleaved and coniferous woodland. Both sets of arborial species encourage rich bird and animal life. A55 Bangor AONB - The coastal zone of Anglesey was designated as an AONB in 1966 and was confirmed in 1967. It is the largest AONB in Wales, covering one third of the island.

Special Landscape Area - Southern Anglesey Estatelands located in southern Anglesey, west of the town of Llanfairpwll. It covers part of the Marquis of Anglesey’s estate, which lies immediately to the north of the AONB-designated shoreline of the Menai Strait. It is considered to provide A55 a valued setting to Anglesey AONB and the Grade I listed parkland of Plas Newydd. Vaynol Estate and Surrounds Special Landscape Area is located on the south shore of the Menai Strait in Gwynedd.

- Grade 1 Registered Parks and Gardens A487 Registered Parks and Gardens A4244 at Vaynol and Plas Newydd. In total 17 Registered Gardens and 17 Country House Gardens located within 5 km of the site.

Ancient Woodland - There are a total of 172 ancient woodland sites across the 5 km study area.

Special Areas of Conservation - SACs represent some of the most important sites for wildlife and the environment. The identified site which falls N within the 5km area is: Menai Strait and Conwy Bay / Y Fenai a Bae Conwy. Local Landscape Designation Map Contains Ordnance Survey data © Crown copyright and database right 100024241(2018)

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Map showing Historic Landscape Aspect Areas Map showing Cultural Landscape Aspect Areas

Prehistoric Historic Landscape Aspect Areas as defined by Natural Customs Cultural Landscape Aspect Areas as defined by Natural Resources Resources Wales in the LANDMAP database Wales in the LANDMAP database Roman There are 15 Historic Landscape Aspect Areas falling Institutions There are 23 Cultural Landscape Aspect Areas falling within the 5 km study within the 5 km study area as described below. area as described below. Medieval up to 1536 Infrastructure • within Gwynedd: Roads; Llanfair Isgaer; Northern Arfon • within Gwynedd: Bangor (Central); Bangor (University); Railway - Chester Post-medieval after 1536 plateau; Bangor mountain; Vaynol; and Y Felinheli (Port Urban to Holyhead; Principal roads; Bryn Cegin and Parc Menai industrial estate; Dinorwic). Bangor Mountain/Arfon plateau; Arfon Plain; Treborth; Sustrans cycle Rural Industrial • on Anglesey: South Anglesey parkland; Fieldscape route; y Faenol; y Felinheli; Plas Menai-watersports centre; and A55. Recent south of Malltraeth; A5 corridor and associated villages; Places • on Anglesey: A5 Road; A5 Road Villages; A55 road; Railway - Chester Coastline around Llandegfan; Fieldscape, Plas Gwyn; to Holyhead; Transport corridor area; Menai Bridge; Southern Anglesey Fieldscape, central eastern Mon; Malltraeth Marsh; Coast – Llandegfan; Sustrans Cycle Route; Central Anglesey; and Plas Brynsiencyn; and Menai Bridge. Newydd, Plas Llanidan. * Customs - leisure/recreation; * Institutions - land division, religion, educational movements; * Infrastructure - tourism, services, communication & transport, education & welfare; * Places - sense of place, name of places.

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2.5 SENSITIVE VISUAL AND CULTURAL HERITAGE RECEPTORS

Legend Braint site, Anglesey

1 Residential properties in Star 2 Bryn Celli Ddu Tumulus Scheduled Monument 3 Filtered views from A4080

Large blocks of mature woodland that screen and filter views from the A4080

Nearest residential receptors

Views from Star: The small settlement of Star sits on higher ground to the north of the proposed Braint site. The mountains of Snowdonia, and more distant Llŷn Peninsula, form an impressive and distinctive back drop in panoramic views over the undulating, well treed, lowland landscape, immediately to the south. The Braint site is visible as a small part of this expansive view from Star. The existing 400 kV OHL is visible to the east crossing over the Menai Strait and a lower voltage lattice line is also visible to the south.

Views from Bryn Celli Ddu: Views to the north-east from Bryn Celli Ddu comprise small scale pastures bounded by a combination of field boundaries, with the existing 400 kV OHL visible on the horizon. A lower voltage lattice OHL is also visible in the mid ground. Views towards the Braint site are screened by the farm at Bryn Celli Ddu, including landforms associated with new dairy units, and intervening woodland blocks.

Views from the A4080: Views north-west towards the Braint Site from the A4080 are often heavily filtered by existing roadside vegetation, undulating landform and intervening woodland blocks.

3

N

Contains public sector information licensed under the Open Government Source: Esri, DigitalGlobe, GeoEye, Earthstar Geographics, CNES/Airbus License v3.0 DS, USDA, USGS, AeroGRID, IGN, and the GIS User Community

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2.6 SITE AND WIDER CONTEXT ANALYSIS

2.6.1 Site Analysis

The Braint site is located within pasture land Star between properties known as Rhosbothan (500 3 m), Llwyn-ogan (200 m) and Tyddyn Fadog (340 m). The strong historic character of this North Wales Expressway landscape,and its sparsely settled character, A55 results in a strong sense of place enhanced by its A5 scenic setting. The site analysis explored the local landscape textures and character in addition to the following key features in the surrounding context:

•1 Homestead: This is the closest residential homestead near the site. Views from this site have been considered in the study

•2 Bryn Celli Ddu Burial Chamber: This scheduled monument is a prominent local attraction

•3 Star: This community is located to the north- west of the site, on rising ground, and would have views into the site which have been considered in the design approaches •4 Plas Newydd House and Gardens: This Grade 1 listed country house set in gardens, 1 parkland and surrounding woodland on the 5 A4080 northern bank of the Menai Strait belongs to the National Trust and is a key landmark and tourist attraction. The grounds form part of a Grade 1 listed Registered Park and Garden. Although the Braint tunnel head house and site would not be directly visible from this area, the character 6 of this complex has been considered in the local MENAI character assessment and design approach. STRAIT 2 Plas Newydd The Essential Setting of the Registered Park House & Gardens and Garden lies to the east of the site Bryn Celli Ddu

5 4 • Views from the A4080: Views north-west N towards the Braint Site from the A4080 are often heavily filtered by existing roadside vegetation, Site Context Analysis Plan undulating landform and intervening woodland Legend Braint site, Anglesey Secondary roads Registered parks blocks Existing settlements Railway Registered gardens Woodland cover Hedgerow network Ancient woodland •6 Llwyn-onn Farm: Listed Building in the area Main roads Watercourse Overhead lines currently undergoing conversion to residential Listed buildings units.

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2.6.2 Site and Context Images

View towards the site from the unnamed local road off A4080. The site is View of site from access road looking west Existing site condition partially screened by existing vegetation.

View of closest homestead to the site. The roof profile has inspired some of View of the site from Star. Views into the site have been considered in the design View of site with Star in the distance the design approaches approaches.

All photographs are taken by Jacobs

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2.6.3 Local Landscape Colours, Materials and Details

During site visits, it was identified that the key influences on the site were both the rural landscape and local estate architecture; these helped inform the design process.

Rural Landscape Some of the key features in this character tapestry include:

• grassland fields with trees and planting;

• formal blocks of planted estate woodland;

• stone walls and Cloddiau.;

• slate roofs;

• barn architecture;

• metal and rusted sheets with a rustic feel;

• stepped roofs;

• vaulted roofs; and

• compacted stone access routes.

All photographs are taken by Jacobs

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2.6.3 Local Landscape Colours, Materials and Details

Estate Architecture The landscape surrounding the Braint site is significantly more planned than that around the Tŷ Fodol site in Gywnedd, and is based around and heavily influenced by estate architecture, particularly the Plas Newydd and Plas Coch estates.

Some of the key features in this

National Trust character tapestry include: AMEC Plas Newydd Plas Coch • bold and iconic architecture surrounded by planting and woodlands that filters views of buildings;

• stone walls;

• stepped gable ends;

• statement architecture surrounded by plantation; AMEC Jim Linwood, Flickr The Menai Bridge Victoria Cottages • slate roofs;

• stone lintels; and

• tower features and chimneys. Stephen E. Roddick, geography Plas Newydd Home Farm Plas Newydd Home Farm drawings showing dressed stone Plas Coch walls and stone lintels

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2.6.4 Sensitive Sites and Heritage The Braint Tunnel Head House site area has a very different character to the Tŷ Fodol Site in Gwynedd, being lowland and gently rolling. The Bryn Celli Ddu complex of chambered tomb and standing stones are Scheduled Monuments (SAM AN02,AN084 and AN085) and are a prominent local tourist attraction. Bryn Celli Ddu marks the summer solstice and popular summer solstice events are held annually at the site.

The greatest influence from the historic environment comes from the Plas Newydd Estate. The Grade I Registered Park and Garden dominates the local area, with numerous estate owned buildings scattered through the adjacent farmland. The listed building descriptions for these structures reference a certain style that was incorporated into each building, such as the distinctive octagonal chimney stacks incorporated into Victoria Cottages.

On Anglesey and in Gwynedd, the traditional method of field boundary construction is a method common to many ‘Celtic’ field systems, the Cloddiau. AMEC These are earthen banks, embedded and faced with stone on the windward Bryn Celli Ddu Burial Chamber side, but more commonly on Anglesey, on both sides. A hedge of gorse was sometimes added along the top of the bank to further deter livestock.

The stones used are small and irregular and would have originally been gathered by field clearance, but later from quarried material. Originally the Cloddiau would have been about 1m high and 1m wide and, when topped by gorse or hedgerow, produced a substantial stock-proof barrier to enclose fields and lanes. AMEC Llwyn-onn Farm AMEC National Trust AMEC Standing stone with Bryn Celli Ddu tomb in the Plas Newydd Plas Coch background

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2.7 VISION, DESIGN OPTIONS & PRINCIPLES - BRAINT

2.7.1 Vision and Design Approach

At the initial stakeholder engagement meeting in May 2017, it was Design Vision suggested that as a general design approach, a farmstead or estate The aspiration for the Tunnel Head House at the Braint site is to create a built form which style building surrounded by trees which give glimpses of the site reflects influences of the local vernacular architecture but does not stand out in the context and Tunnel Head House would be preferred. of this rural area. The built form will be largely surrounded by proposed vegetation which mitigates the direct views into the site but provides glimpses into the built form, reflecting the Officers from the Isle of Anglesey County Council also suggested visual imagery of the estate style architecture. that a built form that doesn’t stand out, but pays due regard to the existing, and often different styles evident in the local vernacular would be preferred. The local vernacular style is heavily influenced AMEC by the localised estate architecture offered by the Plas Newydd N and Plas Coch estates. However it is essential that this style isn’t View from Star slavishly replicated for the Tunnel Head House and operational compound.

The design approaches shown in this section reflect the two key influences observed during site visits and also explore forms from the surrounding region and the local visual tapestry as key inspirations for potential materials, treatments and finishes.

Tunnel Shaft View from access road & A4080

AMEC View from Homestead National Trust Massing and View Influences • The key design approach to massing has been to take the operational spaces that are required and break it down into four massing blocks that could be articulated and modulated to create a more visually interesting built form; and • The key views that have been considered include the views from the access road and A4080, Bryn Celli Ddu, the homestead and the community of Star. AMEC

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Braint Site Building Functional Design

This page shows the minimum functional engineering 0 design elevations100 for the Braint Head House.200 This 300 would have been the basic design that would usually be used for such head houses. The preferred design attempts to articulate this massing to respond to the sensitive views and character areas around the site.

2 3 4 1 0003 0003 0003 5 0003 1 2 B 0003 A 29860 16900

Indicative Roof Indicative Roof 4500 4500

Elevation 3 Elevation 4 1 : 100 1 : 100

4 3 2 1 2 0003 0003 0003 1 A 0003 5 B 0003 29860 16900

Indicative Roof Indicative Roof 4500 4500 This is a conceptual design only and would have been subject to further structural design Elevation 1 Elevation 2 in the detailed stages. 1 : 100 1 : 100

North Wales Connection Project

Mott MacDonald Ltd, Victory House, Trafalgar Place, Brighton, BN1 4FY

nationalgrid National Grid plc, Warwick Technology Park, Gallows Hill, Warwick, CV34 6DA Title Anglesey Headhouse Elevations Headhouse Building NOTES Anglesey - Braint 1. DO NOT SCALE FROM THIS DRAWING. ISSUE P02 2. DRAWING TO BE READ IN CONJUNCTION WITH RELEVANT SHAFT, TUNNEL, CIVIL AND ELECTRICAL DRAWINGS. 3. HEADHOUSE STRUCTURE IS NOT DESIGNED AND SHOWN INDICATIVELY Site 4. HEADHOUSE CLADDING / BUILDING ENVELOPE IS NOT DESIGNED AND SHOWN INDICATIVELY Anglesey A1 DRAWN ZP Originator Drawing Number 356526 - MMD - 01 - ZZ - DR - A - 0002 CAD CHECKED TD NG Drawing Number Sheet No. No. of Sheets ISSUE 0002 P02 APPROVED/DATE AF 12/05/17

PRELIMINARY ISSUE PRELIMINARY SCALE:- National Grid plc owns the Copyright of this Document. It may not be reproduced or transmitted in any form or for any purpose, without the express written permission of National Grid plc Tunnel Head House Design Guide Document 7.19 26

2.7.2 Braint Site Building Form Preferred Option and Key Design Principles

In August 2017, three design options (as outlined on pages 28-30) were presented to the key stakeholder group at the Isle of Anglesey County Council. Based Key view from Star on the feedback from that group, a revised version of Option 3 has emerged as National Grid’s preferred View from Homestead design approach with the following key design 3 principles:

Key Design Principles 2 1• The building volume would not exceed 4350 m³ with a maximum building height of 8 m • Front massing to be designed as a high element with 5 2 4 a low pitch gable roof, with slate-effect panel roofing 6 and short overhang, reminiscent of Plas Newydd Home Farm architecture 7 3• Vaulted roofs with corrugated metal for rear Star sections to reduce the visual impact that pitched roof reflections could have for views from Star. The View point mass closest to Star may be lowered further to provide visual articulation depending on functional

constraints Access Route 4• Louvres could be architecturally enhanced through Homestead a suitable colour palette, detailing etc. The physical dimension of the louvres would largely be dictated by View from Access Road Bryn Celli Ddu operational considerations such as air flow rates and Location Plan noise attenuation. Potential for stone or dark brick This architectural sketch provides an illustrative means of interpreting the Key Design Principles. The finalTunnel lintels to reflect local architecture depending on cost Head House is likely to differ somewhat in form and scale within the parameters of the DCO. and functional viability External safety and maintenance equipment including Fall Arrest system at roof height are likely to be provided. 5• The use of smaller recesses would add visual interest to the façade 6• Building facade to be broken with visually heavy stone walls or cladding along the bottom half and linear metal or wood-effect, striated cladding for the top half

7• Potential to transition stone base to metal cladding on side elevations reminiscent of old farms and as a cost efficient design. AMEC Llwyn-onn Farm Sketch of Plas Newydd Home Farm Example of vaulted rural architecture

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The below architectural sketches provide an illustrative means of interpreting the Key Design Principles. The final Tunnel Head House is likely to differ somewhat in form and scale within the parameters of the DCO. External safety and maintenance equipment including Fall Arrest system at roof height are likely to be provided. steadmans ©

Oblique view from the south west showing façades towards the access road and the adjacent homestead

Oblique view from the north-east showing façades towards Star

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2.7.3 Braint Site Building Form Initial Option 1

The first option focused on breaking up the massing of the building into four parts with distinct roof forms while breaking up the walls with a mix of materials.

Design features View from Homestead Key view from Star 4 1• Higher built form to the front of the site, stepping down to the back to present a lower 3 built form profile when viewed from Star 7 2• Double gable-ended roof with a barn or stock- shed style roof profile to create visual interest 1 along the front elevation

3• Lower pitched roofs to the back 5 2

4• The mass closest to Star lowered further for 6 visual articulation Star 5• Louvres could be architecturally enhanced

through suitable colour palette, detailing View point etc. The physical dimension of the louvres will largely be dictated by operational

considerations such as air flow rates and noise Access Route

attenuation. Potential for stone or brick lintels to Homestead reflect local architecture 6• Wall faces broken up into two sections. The Bryn Celli Ddu lower half to have a visually heavier material Location Plan such as stone cladding or gabion wall with waste slate. The upper section could be brick or View from Access Road lighter patterns of stone

7• The front elevation, along the access road, would have a more enhanced material palette while the rear sections could be metal cladding with colours that blend into the landscape. AMEC

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2.7.4 Braint Site Building Form Initial Option 2

The second option explored an estate style massing, roof profile and materials, not necessarily imitating the style but reflecting the local vernacular architecture. View from Homestead Key view from Star Design features

1• Stepped roof feature for facade wall reminiscent of Plas Coch but designed in a contemporary style 7 creating an engaging front facade 4 2• Pitched roof behind facade stepped profile in slate- effect panels or muted coloured metal panels to 3 create a low profile 2 3• Higher massing along front facade over the shaft stepping to minimum required heights in the mass 6 that may be potentially visible from Star 1

4• Vaulted roofs for rear sections to reduce visual 5 impact that pitched roof reflections could have for

the mass potentially visible from Star Star 5• Front wall face broken into two sections with stone in lower section and potentially brick or muted View point colour metal work to the top. Alternatively, the front facade could have stone cladding for the full extent. The side walls could have muted colour Access Route metalwork Homestead View from Access Road 6• Louvres could be architecturally enhanced through Bryn Celli Ddu suitable colour palette, detailing etc. The physical Location Plan dimension of the louvres will largely be dictated by operational considerations such as air flow rates and noise attenuation. Potential for stone or brick lintels to reflect local architecture

7• Slate-effect panels or muted grey metal sheets could be considered for roofs. Stephen E. Roddick, geography

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2.7.5 Braint Site Building Form Initial Option 3

The third option explored a style and design language inspired by Plas Newydd Home Farm. However, the intention was to reflect on the design elements and form rather than mimic them.

Design features View from Homestead Key view from Star 4 • Front massing to be designed as a higher 1 2 element with a low hipped roof with slate-effect panels or muted coloured metal roofing and short 3 overhang reminiscent of Plas Newydd Home Farm architecture

•2 Mid rise tower feature over the stairs and lift shaft as a design feature to enhance the front elevation. 6 This feature could have louvres to enhance visual articulation and a rounded top, but would have 5 increased maximum building height 1 Star •3 Vaulted roofs for rear sections to reduce visual impact that pitched roof reflections could have for View point mass potentially visible from Star 7 •4 The mass closest to the Star is lowered further for visual articulation Access Route Homestead •5 Louvres could be architecturally enhanced through suitable colour palette, detailing etc. The physical Bryn Celli Ddu dimension of the louvres will largely be dictated by Location Plan operational considerations such as air flow rates and noise attenuation. Potential for arched stone or dark brick lintels to reflect local architecture View from Access Road depending on cost and functional viability •6 The use of smaller fenestration and openings could add visual interest to the façades

•7 Stone walls or cladding with feature elements would provide an interesting front elevation while the side walls could have wood-effect panels or similar vertical, striated cladding.

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2.8 Landscape Design Approach

The proposed landscape setting and design approach for the Braint Tunnel Headhouse and CSEC is as follows:

• existing trees retained along the south-eastern boundary to filter views from the east from properties at Llwyn Ogan (500 m);

• proposed planting and mounding around the northern and southern boundaries to help filter views from Star and Tyddyn Fadog;

• the shape of proposed woodland blocks mimic the surrounding woodlands to integrate the site with the characteristics of the Southern Anglesey Estatelands Special Landscape Area within which the site lies;

• the attenuation pond would be designed as a part of the landscape setting of the site and to offer bio-diversity benefits; Existing trees retained to filter views from the east from properties at • land to the south and west of the site to be Llwyn Edwen raised and returned to agricultural use;

• planting mixes to comprise largely indigenous species with both deciduous and evergreen components to provide year round screening and bio-diversity benefits;

• locally appropriate wild flower seeding mixes to be used to provide interest and bio-diversity benefits for invertebrates; and

• potential opportunities for other wildlife enhancements to be incorporated including bird nesting boxes and establishing wider movement corridors. N

Landscape Masterplan Imagery ©2018 Getmapping plc, Map data ©2018 Google

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2.9 Photomontages

The adjoining photomontages show the existing and proposed view of the Braint Tunnel Headhouse and CSEC within the surrounding site context.

As shown in these images, the built form is set back from the boundaries and surrounded by landscape treatments which mitigate any visual impacts on sensitive views from the surrounding context.

The articulation of the built form and the use of materials and colours as discussed in the Design Guide would present a visually appropriate built form within a landscape setting in this context. Aerial Imagery provided by National Grid View of existing Site Aerial Imagery provided by National Grid View of proposed built form and landscape treatments

North Wales Connection Project Tunnel Head House Design Guide Document 7.19 33

1 2 Photomontages 1• View from the east of the site showing the building in the landscape setting 2• View from the south showing the pitched and vaulted roofs and the stepped stone feature 3• View from the east 4• View from the north east showing the step down of the built form to reduce the mass as seen from views from the Star community 5• View from south 6• Front facade showing variation in materials and the louvres treatment 3 4 7• View from the east showing the slate-effect roof and step down of the massing The landscaping is shown at year 15. Electrical plant and equipment omitted for clarity.

5

6 7

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2.10 MATERIALS PALLET

2.10.1 Built Form

H

A B C D

H F

E G I

A fibreglass slate tile roofing © shapes grp B example of stone base and striated metal cladding wall C formed concrete panelling D flint and brick facade © flintwall co E vaulted roof example F metal roof © eric hands, flickr G slate effect, meta-slate roofing system © steadmans H fine grain louvres © colt int. ltd Indicative colour palette I dark coloured brick

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2.10.2 Access and Surface Treatments

A H

B C D E

I

G

F K J

A grasscrete G coloured asphalt © aggregate.com B bodpave 85 © terram.com H coloured asphalt with green chippings © pavingexpert.com C tar-macadam surface I gravel and tar spray and chip D blue-grey slate chippings © suttles.co.uk J gabion wall with waste slate © smallwood-gabion.co.uk E pebbles stones K buff-grey self-binding gravel F gravel

North Wales Connection Project Tunnel Head House Design Guide Document 7.19 36

2.10.3 Traditional Fencing & Secure Fencing

A C

B D A / B cloddiau style boundary feature C galvanised palisade fence for secure compounds D stock fencing © jonrichardscontracting.co.uk

North Wales Connection Project Tunnel Head House Design Guide Document 7.19 37

THE NATIONAL GRID (NORTH WALES CONNECTION PROJECT) ORDER GORCHYMYN NATIONAL GRID (PROSIECT CYSYLLTIAD GOGLEDD CYMRU) DESIGN PLAN: PARAMETER PLAN FOR TŶ FODOL TUNNEL HEAD HOUSE AND CYNLLUN DYLUNIO: CYNLLUN O’R PARAMEDR AR GYFER PRIF DŶ TWNNEL TŶ FODOL 3.0 Tŷ Fodol Tunnel Headhouse and CSEC CABLE SEALING END COMPOUND A’R COMPOWND SY’N SELIO PENNAU CEBLAU REGULATION 5(2)(o) RHEOLIAD 5(2)(o) SHEET 5 OF 8 DALEN 5 O 8 3.1 INTRODUCTION GWYNEDD COUNCIL CYNGOR GWYNEDD ANGLESEY

Within two existing agricultural fields, the not be the main feature. The use of slate proposed Tŷ Fodol Tunnel Headhouse and is very prevalent in this location; GWYNEDD CSEC would be located to the north-west of • large agricultural silos (between 15 Pentir Substation, south of Fodolydd Lane. and 20m high) are not uncommon in Legend / Allwedd

TEMPORARY CONSTRUCTION this area and these design principles COMPOUND AREA INDICATIVE AREA WITHIN WHICH POSSIBLE could be replicated, especially for the LANDSCAPING / MITIGATION Initial Stakeholder Engagement WILL TAKE PLACE taller ventilation-related elements where ZONE WITHIN WHICH FULL Some of the key themes that emerged from LINE TENSION GANTRIES AND CABLE SEALING END the initial stakeholder engagement in May louvres could be considered; WILL BE LOCATED ZONE WITHIN WHICH TUNNEL HEAD HOUSE WILL BE 2017 with officers from Gwynedd Council • use of hedgerows and Crawiau (a typical LOCATED AREA WITHIN WHICH TUNNEL HEAD HOUSE AND CABLE were as follows: landscape feature of the immediate area) SEALING END COMPOUND WILL BE LOCATED

ILLUSTRATIVE SIZE OF THE is important to ensure the site can be TUNNEL HEAD HOUSE AND CABLE SEALING END • it was considered that a design approach COMPOUND integrated as successfully as possible into reflecting the local vernacular and rural ILLUSTRATIVE LOCATION OF THE TUNNEL HEAD HOUSE (MAXIMUM DIMENSIONS the wider landscape, including screening MEASURED EXTERNALLY architecture, which is predominantly (H) 11m VOLUME 9,300m³) access tracks. It was suggested that a ILLUSTRATIVE ROUTE OF agricultural in style, would be more in PERMANENT ACCESS ROAD mix/mosaic of different materials and keeping with this site. The predominant THE NATIONAL GRID (NORTH WALES CONNECTION PROJECT) ORDER GORCHYMYN NATIONAL GRID (PROSIECT CYSYLLTIAD GOGLEDD CYMRU) ZONE WITHIN WHICH DESIGN PLAN: PARAMETER PLAN FOR TŶ FODOL TUNNEL HEAD HOUSE AND CYNLLUN DYLUNIO: CYNLLUN O’R PARAMEDR AR GYFER PRIF DŶ TWNNEL TŶ FODOL PERMANENT ACCESS ROAD THE NATIONAL GRIDCABLElandscape (NORTH SEALING WALES END CONNECTION COMPOUND PROJECT)treatments ORDER be used on bothGORCHYMYN NATIONALA’R COMPOWND GRID (PROSIECT SY’N SELIO CYSYLLTIAD PENNAU CEBLAU GOGLEDD CYMRU) WILL BE LOCATED materials in the area are stone, timber DESIGN PLAN: PARAMETER PLANREGULATION FOR TŶ FODOL5(2)(o) TUNNEL HEAD HOUSE AND CYNLLUN DYLUNIO: CYNLLUN O’R RHEOLIADPARAMEDR 5(2)(o) AR GYFER PRIF DŶ TWNNEL TŶ FODOL CABLE SEALINGSHEET END 5 OF COMPOUND 8 A’R COMPOWND DALENSY’N SELIO 5 O 8 PENNAU CEBLAU CYNGOR GWYNEDD 1. This drawing is scaled at paper size A1, therefore any prints taken at theGWYNEDDREGULATION built COUNCIL 5(2)(o) form and the ground plane, RHEOLIAD 5(2)(o) smaller sizes will affect accuracy of the measurement units and should not be scaled against. SHEET 5 OF 8 DALEN 5 O 8 and metal. A design which is relatively low ANGLESEY inGWYNEDD order COUNCIL to reduce the dominance of a CYNGOR GWYNEDD ANGLESEY key and able to blend into the landscape 0 30 60 Metres is preferred; large-scale built form in the landscape,

and to minimise the prominence of direct GWYNEDD • the Welsh Water treatment works at changes to the landscape itself, such as GWYNEDD Garndolbenmaen was stated as a good access tracks; A FOR DCO SUBMISSION KJ SR RP Legend / Allwedd local example of where good design has THE NATIONAL GRID THE NATIONAL GRID (NORTH WALES CONNECTION PROJECT) ORDER GORCHYMYN NATIONAL GRID (PROSIECT CYSYLLTIAD GOGLEDD CYMRU) (NORTH WALES CONNECTION PROJECT) ORDER Legend / AllweddTEMPORARY CONSTRUCTION DESIGN PLAN: PARAMETER PLAN FOR TŶ FODOL DESIGN PLAN: PARAMETER PLAN FOR TŶ FODOL TUNNEL HEAD HOUSE AND • generallyCYNLLUN DYLUNIO: CYNLLUN in O’R the PARAMEDR local AR GYFER PRIFenvironment, DŶ TWNNEL TŶ FODOL COMPOUND AREA TUNNEL HEAD HOUSE AND CABLE SEALING THE NATIONAL GRID (NORTH WALES CONNECTION PROJECT) ORDER GORCHYMYN NATIONAL GRID (PROSIECT CYSYLLTIAD GOGLEDD CYMRU) END COMPOUND been implementedCABLE SEALING in END COMPOUNDa rural landscape A’R COMPOWND SY’N SELIO PENNAU CEBLAU REGULATION 5(2)(o) TEMPORARY CONSTRUCTION DESIGN PLAN: PARAMETER PLAN FOR TŶ FODOL TUNNEL HEAD HOUSE AND CYNLLUN DYLUNIO: CYNLLUN O’R PARAMEDR AR GYFER PRIF DŶ TWNNEL TŶ FODOL SHEET 5 OF 8 THE NATIONAL GRID (NORTHREGULATION WALES CONNECTION 5(2)(o) PROJECT) ORDER GORCHYMYN NATIONAL GRIDRHEOLIAD (PROSIECT 5(2)(o) CYSYLLTIAD GOGLEDD CYMRU) INDICATIVECOMPOUND AREA AREA WITHIN THE NATIONAL GRIDCABLE (NORTH SEALING WALES END CONNECTION COMPOUND PROJECT) ORDER GORCHYMYN NATIONALA’R COMPOWND GRID (PROSIECT SY’N SELIO CYSYLLTIAD PENNAU CEBLAU GOGLEDD CYMRU) WHICH POSSIBLE GWYNEDD COUNCIL DESIGN PLAN: PARAMETER PLANSHEET FOR TŶ5 OF FODOL 8 TUNNEL HEAD HOUSE AND agricultural buildingsDALEN 5 O 8 have extended DESIGN PLAN: PARAMETER PLANREGULATION FOR TŶ FODOL5(2)(o) TUNNEL HEAD HOUSE AND CYNLLUN DYLUNIO: CYNLLUN O’R RHEOLIADPARAMEDR 5(2)(o) AR GYFER PRIF DŶ TWNNEL TŶ FODOL LANDSCAPING / MITIGATION for a utilities infrastructureCABLEGWYNEDD SEALING END COUNCIL COMPOUND scheme. The A’R COMPOWNDCYNGOR SY’N SELIOGWYNEDD PENNAU CEBLAU INDICATIVEWILL TAKE PLACE AREA WITHIN GORCHYMYN NATIONAL GRID CABLE SEALINGSHEET END 5 OF COMPOUND 8 A’R COMPOWND DALENSY’N SELIO 5 O 8 PENNAU CEBLAU WHICH POSSIBLE (PROSIECT CYSYLLTIAD GOGLEDD CYMRU) REGULATION 5(2)(o) RHEOLIAD 5(2)(o) CYNLLUN DYLUNIO: CYNLLUN O’R PARAMEDR AR GWYNEDDREGULATION COUNCIL 5(2)(o) CYNGORRHEOLIAD GWYNEDD 5(2)(o) ANGLESEY LANDSCAPING / MITIGATION SHEET 5 OF 8 gradually overDALEN time. 5 O 8 The result is that ZONEWILL TAKE WITHIN PLACE WHICH FULL GYFER PRIF DŶ TWNNEL TŶ FODOL A’R SHEET 5 OF 8 DALEN 5 O 8 COMPOWND SY’N SELIO PENNAU CEBLAU CYNGOR GWYNEDD LINE TENSION GANTRIES different use of materialsGWYNEDD COUNCIL and colours to CYNGOR GWYNEDD ANGLESEY AND CABLE SEALING END RHEOLIAD 5(2)(o) ZONEWILL BE WITHIN LOCATED WHICH FULL DALEN 5 O 8 CYNGOR GWYNEDD ANGLESEY LINE TENSION GANTRIES buildings have a variety of forms, styles ANGLESEY AND CABLE SEALING END N break up mass, a good site positioning ZONEWILL BE WITHIN LOCATED WHICH TUNNEL HEAD HOUSE WILL BE LOCATED ZONE WITHIN WHICH TUNNEL and a wide variety of materials. It would Application Number / Rhif y Cais HEAD HOUSE WILL BE EN020015 and use of landscaping were considered GWYNEDD LOCATEDAREA WITHIN WHICH TUNNEL Tŷ Fodol Tunnel Headhouse and CSEC OutlineHEAD HOUSE Plan AND CABLE for DCO application Contains Ordnance Survey data © Crown National Grid Drawing Reference / Cyfeirnod Lluniad National Grid be a good idea to use a mix of forms as GWYNEDD SEALING END COMPOUND DCO_DE/PS/09_05 WILLAREA BE WITHIN LOCATED WHICH TUNNEL good design approaches; GWYNEDD HEAD HOUSE AND CABLE GWYNEDD SEALING END COMPOUND copyright and database right 100024241(2018) 1:1000 A1 SHEET 5 OF 8 A ILLUSTRATIVE SIZE OF THE WILL BE LOCATED a design approach to reflect this type of TUNNEL HEAD HOUSE AND CABLE SEALING END ILLUSTRATIVECOMPOUND SIZE OF THE • reflections from roofs is considered an LEGEND TUNNEL HEAD HOUSE AND Legend / Allwedd CABLE SEALING END design narrative. For instance, the taller COMPOUND Legend / Allwedd ILLUSTRATIVE LOCATION OF TEMPORARY CONSTRUCTION THE TUNNEL HEAD HOUSE issue in the area. However, designing COMPOUNDTemporary AREA construction compound area (MAXIMUM DIMENSIONS Legend / Allwedd ILLUSTRATIVEIllustrative LOCATION OF location of the tunnel head Legend / AllweddTEMPORARY CONSTRUCTION MEASURED EXTERNALLY ventilation unit could be designed as a (H)THE 11m TUNNEL VOLUME HEAD 9,300m³) HOUSE COMPOUND AREA INDICATIVE AREA WITHIN (MAXIMUMhouse DIMENSIONS (Maximum dimensions measured TEMPORARYWHICH POSSIBLE CONSTRUCTION TEMPORARYIndicative CONSTRUCTION area within which possible MEASURED EXTERNALLY the roofs to align with the background LANDSCAPINGCOMPOUND AREA / MITIGATION INDICATIVE AREA WITHIN (H) 11mexternally VOLUME 9,300m³) (H) 11 m volume 9,300 m³) COMPOUND AREA ILLUSTRATIVE ROUTE OF WHICHWILL TAKE POSSIBLE PLACE barn whereas the welfare rooms could landscaping / Mitigation would take PERMANENT ACCESS ROAD INDICATIVELANDSCAPING AREA / MITIGATION WITHIN INDICATIVE AREA WITHIN WHICHWILL TAKE POSSIBLE PLACE ZONEWHICHplace WITHIN POSSIBLE WHICH FULL ILLUSTRATIVE ROUTE OF mountain slopes should be considered; LANDSCAPING / MITIGATION Illustrative route of permanent LANDSCAPINGLINE TENSION GANTRIES/ MITIGATION PERMANENT ACCESS ROAD WILL TAKE PLACE look like a smaller agricultural unit; and ZONEWILLAND CABLETAKE WITHIN PLACE SEALING WHICH FULLEND ZONE WITHIN WHICH LINEWILL TENSIONBE LOCATED GANTRIES access road Zone within which full line tension PERMANENT ACCESS ROAD ZONEAND CABLE WITHIN SEALING WHICH FULLEND ZONE WITHIN WHICH FULL WILL BE LOCATED LINEWILL TENSIONBE LOCATED GANTRIES • there are several farmsteads in the LINEZONEgantries TENSION WITHIN WHICH GANTRIES TUNNEL and cable sealing end would ZONE WITHIN WHICH AND CABLE SEALING END HEADAND CABLE HOUSE SEALING WILL BE END PERMANENT ACCESS ROAD WILL BE LOCATED Zone within which permanent • the operational compound is going in a LOCATEDbe located WILL BE LOCATED ZONEWILL BE WITHIN LOCATED WHICH TUNNEL 1. This drawing is scaled at paper size A1, therefore any prints taken at smaller sizes will affect accuracy of the measurement units and should not HEAD HOUSE WILL BE be scaled against. access road would be located locality which typically use juniper (and LOCATEDZONE WITHIN WHICH TUNNEL ZONE WITHIN WHICH TUNNEL 1. This drawing is scaled at paper size A1, therefore any prints taken at HEADAREAZone HOUSEWITHIN WILLWHICH within BE TUNNEL which tunnel head house HEAD HOUSE WILL BE smaller sizes will affect accuracy of the measurement units and should not location which could affect the view of HEAD HOUSE AND CABLE be scaled against. LOCATED LOCATED SEALINGAREAwould WITHIN END WHICHCOMPOUND be TUNNEL located similar) green and grey or slate colours. HEADWILL BE HOUSE LOCATED AND CABLE 0 30 60 Metres SEALINGAREA WITHIN END WHICHCOMPOUND TUNNEL AREA WITHIN WHICH TUNNEL the mountains from the Standing Stone ILLUSTRATIVEHEADWILLArea BE HOUSE LOCATED AND SIZE within CABLE OF THE which tunnel head house HEAD HOUSE AND CABLE 0 30 60 SEALINGTUNNEL HEAD END COMPOUND HOUSE AND SEALING END COMPOUND Metres CABLEWILLand BE SEALING LOCATED cable END sealing end compound A mass use of localised stone material ILLUSTRATIVEWILL BE LOCATED SIZE OF THE COMPOUNDTUNNEL HEAD HOUSE AND Schedule Monument, hence the built form ILLUSTRATIVECABLEwould SEALING SIZE END be OF THE located ILLUSTRATIVE SIZE OF THE COMPOUNDTUNNEL HEAD HOUSE AND TUNNEL HEAD HOUSE AND ILLUSTRATIVECABLE SEALING LOCATION END OF would probably not be practical and would CABLE SEALING END COMPOUNDTHE TUNNEL HEAD HOUSE COMPOUNDIllustrative size of the tunnel head and landscape treatment impact on the ILLUSTRATIVE(MAXIMUM DIMENSIONS LOCATION OF MEASUREDTHEhouse TUNNEL EXTERNALLY HEAD HOUSEand cable sealing end (H) 11m VOLUME 9,300m³) ILLUSTRATIVE(MAXIMUM DIMENSIONS LOCATION OF not be preferred. However gabion walls ILLUSTRATIVE LOCATION OF A FOR DCO SUBMISSION KJ SR RP MEASUREDTHEcompound TUNNEL EXTERNALLY HEAD HOUSE THE TUNNEL HEAD HOUSE setting of the Scheduled Monument would (MAXIMUM(H) 11m VOLUME DIMENSIONS 9,300m³) (MAXIMUM DIMENSIONS ILLUSTRATIVEMEASURED EXTERNALLY ROUTE OF MEASURED EXTERNALLY A FOR DCO SUBMISSION KJ SR RP PERMANENT(H) 11m VOLUME ACCESS 9,300m³) ROAD (H) 11m VOLUME 9,300m³) THE NATIONAL GRID with waste slate may be considered. (NORTH WALES CONNECTION PROJECT) ORDER ILLUSTRATIVE ROUTE OF PERMANENT ACCESS ROAD DESIGN PLAN: PARAMETER PLAN FOR TŶ FODOL be a critical consideration. TUNNEL HEAD HOUSE AND CABLE SEALING THE NATIONAL GRID ILLUSTRATIVE ROUTE OF END COMPOUND (NORTH WALES CONNECTION PROJECT) ORDER ILLUSTRATIVE ROUTE OF REGULATION 5(2)(o) PERMANENTZONE WITHIN ACCESS WHICH ROAD DESIGN PLAN: PARAMETER PLAN FOR TŶ FODOL PERMANENT ACCESS ROAD SHEET 5 OF 8 Corrugated iron/corten steel could be TUNNEL HEAD HOUSE AND CABLE SEALING PERMANENT ACCESS ROAD GWYNEDD COUNCIL WILL BE LOCATED END COMPOUND ZONE WITHIN WHICH REGULATION 5(2)(o) PERMANENT ACCESS ROAD GORCHYMYNSHEET NATIONAL 5 OF 8 GRID ZONEWILL BE WITHIN LOCATED WHICH (PROSIECT GWYNEDDCYSYLLTIAD COUNCIL GOGLEDD CYMRU) used for parts of the built form but should 1. This drawing is scaled at paperZONE size A1, WITHIN therefore any WHICH prints taken at CYNLLUN DYLUNIO: CYNLLUN O’R PARAMEDR AR PERMANENT ACCESS ROAD GYFER PRIF DŶ TWNNEL TŶ FODOL A’R smaller sizes will affect accuracyPERMANENT of the measurement ACCESS units and should ROAD not GORCHYMYN NATIONAL GRID be scaled against. WILL BE LOCATED COMPOWND SY’N SELIO PENNAU CEBLAU WILL BE LOCATED (PROSIECT CYSYLLTIAD GOGLEDD CYMRU) 1. This drawing is scaled at paper size A1, therefore any prints taken at RHEOLIAD 5(2)(o) CYNLLUN DYLUNIO: CYNLLUN O’R PARAMEDR AR smaller sizes will affect accuracy of the measurement units and should not DALEN 5 O 8 GYFER PRIF DŶ TWNNEL TŶ FODOL A’R be scaled against. CYNGOR GWYNEDD 1. This drawing is scaled at paper size A1, therefore any prints taken at COMPOWND SY’N SELIO PENNAU CEBLAU 1.smaller This drawing sizes iswill scaled affect at accuracy paper size of the A1, measurement therefore any unitsprints and taken should at not RHEOLIAD 5(2)(o) besmaller scaled sizes against. will affect accuracy of the measurement units and should not DALEN 5 O 8 0 be scaled against. 30 60 Metres CYNGOR GWYNEDD 0 30 60 Metres Application Number / Rhif y Cais 0 30 60 EN020015 0 30 60 Metres National Grid Drawing Reference / Cyfeirnod Lluniad National Grid Metres Application Number / Rhif y Cais DCO_DE/PS/09_05 EN020015

National Grid Drawing Reference / Cyfeirnod Lluniad National Grid 1:1000 A1DCO_DE/PS/09_05SHEET 5 OF 8 A

1:1000 A1 SHEET 5 OF 8 A

A FOR DCO SUBMISSION KJ SR RP

A FOR DCO SUBMISSION KJ SR RP THE NATIONAL GRID A (NORTH WALESFOR DCO CONNECTION SUBMISSION PROJECT)KJ SR ORDERRP A DESIGN PLAN:FOR PARAMETER DCO SUBMISSION PLAN KJFOR TŶSR FODOLRP North Wales Connection Project TUNNEL HEADTHE HOUSE NATIONAL AND GRID CABLE SEALING (NORTH WALESEND CONNECTION COMPOUND PROJECT) ORDER DESIGN PLAN: REGULATIONPARAMETER PLAN5(2)(o) FOR TŶ FODOL TUNNEL HEADTHE HOUSE NATIONAL AND GRID CABLE SEALING (NORTH WALESTHE CONNECTIONSHEET NATIONAL 5 OF GRID8 PROJECT) ORDER (NORTH WALESGWYNEDDEND CONNECTION COMPOUND COUNCIL PROJECT) ORDER DESIGN PLAN: REGULATIONPARAMETER PLAN5(2)(o) FOR TŶ FODOL DESIGNTUNNEL PLAN: HEAD PARAMETER HOUSE AND PLAN CABLE FOR SEALING TŶ FODOL TUNNEL HEAD HOUSESHEET 5AND OF 8CABLE SEALING GORCHYMYNGWYNEDDEND COMPOUND NATIONAL COUNCIL GRID (PROSIECT REGULATIONCYSYLLTIADEND COMPOUND GOGLEDD 5(2)(o) CYMRU) CYNLLUN DYLUNIO:REGULATIONSHEET CYNLLUN 5 OF 5(2)(o) O’R8 PARAMEDR AR GYFERGORCHYMYN PRIFGWYNEDD DŶSHEET TWNNEL NATIONAL 5COUNCIL OF TŶ8 FODOL GRID A’R (PROSIECTCOMPOWND GWYNEDDCYSYLLTIAD SY’N SELIO COUNCIL GOGLEDD PENNAU CEBLAU CYMRU) CYNLLUN DYLUNIO:RHEOLIAD CYNLLUN 5(2)(o) O’R PARAMEDR AR GYFERGORCHYMYN PRIF DŶ TWNNEL NATIONAL TŶ FODOL GRID A’R (PROSIECTGORCHYMYN CYSYLLTIADDALEN NATIONAL 5 OGOGLEDD 8 GRID CYMRU) (PROSIECTCOMPOWND CYNGORCYSYLLTIAD SY’N SELIO GWYNEDD GOGLEDD PENNAU CEBLAU CYMRU) CYNLLUN DYLUNIO:RHEOLIAD CYNLLUN 5(2)(o) O’R PARAMEDR AR CYNLLUNGYFER DYLUNIO: PRIF DŶ CYNLLUN TWNNEL TŶO’R FODOL PARAMEDR A’R AR GYFER PRIF DŶDALEN TWNNEL 5 O 8 TŶ FODOL A’R COMPOWNDCYNGOR SY’N SELIO GWYNEDD PENNAU CEBLAU COMPOWNDRHEOLIAD SY’N SELIO 5(2)(o) PENNAU CEBLAU RHEOLIADDALEN 5 5(2)(o)O 8 CYNGORDALEN GWYNEDD 5 O 8 Application Number / Rhif CYNGORy Cais GWYNEDD EN020015

ApplicationNational Grid Number Drawing / Rhif Reference y Cais / Cyfeirnod Lluniad National Grid DCO_DE/PS/09_05EN020015 Application Number / Rhif y Cais ApplicationNational Grid Number Drawing / Rhif Reference y Cais / Cyfeirnod Lluniad National Grid DCO_DE/PS/09_05EN020015 1:1000 A1 EN020015SHEET 5 OF 8 A National Grid Drawing Reference / Cyfeirnod Lluniad National Grid National Grid Drawing Reference / Cyfeirnod Lluniad National Grid DCO_DE/PS/09_05 1:1000 A1DCO_DE/PS/09_05SHEET 5 OF 8 A

1:1000 A1 SHEET 5 OF 8 A 1:1000 A1 SHEET 5 OF 8 A Tunnel Head House Design Guide Document 7.19 38

3.2 REGIONAL CONTEXT

Gwynedd

Wales

Gwynedd is located on the most westerly part of mainland North Wales. Main towns in the county are Bangor, Caernarfon; Ffestiniog; Llanddeiniolen and Bethesda.

The landscape and habitats, together with the species dependent upon them, are recognised as being of local, national and international value. A substantial part of the County, 174,200 ha (63%) has been designated as the Snowdonia National Park. The north west of Gwynedd incorporates the Llŷn Area of Outstanding Natural Beauty, which also has large sections of Heritage Coast.

Geographically, the area consists mainly of mountains and coasts. Mountainous areas are the most distinct landscapes found in Gwynedd. At 1085m height Snowdon is the highest mountain in Wales and England. The area encompasses many spectacular uplands including all 15 mountain peaks in Wales over 3000 feet. There are numerous glacial features including sharp ridges, cirques, cliffs, lakes, bogs, rivers and waterfalls. The landscape pattern and cover is varied comprising planned, formal parkland, estate farms and settlements including hill sheep grazing, forestry, heather dominated moorland and upland grassland. Rock outcrops and slate/shale ridges and screes are frequently apparent.

Agriculture is the main land use with villages and small towns found inland and most of the larger towns focussed along the coast. Hefin Owen,Flickr Britannia Bridge

North Wales Connection Project Tunnel Head House Design Guide Document 7.19 39

3.3 STRATEGIC LANDSCAPE CONTEXT

Leend Leend 1 / Head House T odol Gnedd Tŷ Fodol site, Gwynedd 1 N / Head House T odol Gnedd Ntion Lndce Crcter Are Ntion Lndce Crcter Are 1 rordir nnglese Coast

1 Canolarth1 rordirdnCentral nnglese nglese Coast

1 ron Canolarth dnCentral nglese 5km ln ron ae TremadogTremadoc a ln rrinodonia 1 ae TremadogTremadoc a 7 Drn ConCona alle rrinodonia Anglesey2 rordir Coln ar GogleddColn and Northern 1 Coastline 7 Drn ConCona alle 1 8 9 rniau hoshos Hills rordir Coln ar GogleddColn and Northern 2 1 nddCoastline HiraethogDenigh oors

1 8 1 Drn9 Drd rniau a langollenlangollen hoshos Hills and the ale o Dee

1 ernern1 ndd HiraethogDenigh oors

1 Drn Drd a langollenlangollen and the 9 ale o Dee 7 3 1 ernern

9 7 3

National Landscape Character Area: Arfon Gwynedd Arfon is literally the land which is ar-fon, ‘against Anglesey’, being the lowland area bounded on the one side by the Menai Strait and on the other by the Snowdonia

10 foothills and the adjacent glaciated valleys that open into it. Extending from Penmaen- bach Point in the north east to Bryncir in the south, it includes the Anglo-Norman boroughs of Caernarfon (with its World Heritage Site castle and town walls) and the 6 cathedral and university city of Bangor.

10 This coastal plateau area also includes the 19th century neo Norman Penrhyn Castle, 5 which dominates the view and whose estate extends for many miles around, as 6 6 well as the less apparent, gentry houses and parklands at Faenol (or Vaynol) and 4 15 Glynllifon.

16 As well as the dwellings of the once-wealthy and powerful, this is also pre-eminently 5 the landscape of the Welsh gwerin, the industrious, progressive and cultured 6 11 1 eters Contains ulic sector inormation licensed under the en Goernment icence . population of the farm, the small-holding, the cottage and the quarry. Their way of 4 15life, brought into being by the tremendous industrial slate quarrying workings of the late 18th and the 19th centuries, has far from vanished, and the Welsh language remains16 particularly strong. The landscape of the gwerin is everywhere, in the form of settlements, chapels, field-boundaries and in the unique environments of the great

1 etersslate quarries, whose working faces and tips dominate the Ogwen and Nantlle valleys Contains ulic sector inormation licensed under the en Goernment icence . and the Llanberis-Llanddeiniolen area. National Landscape Character Areas

North Wales Connection Project Tunnel Head House Design Guide Document 7.19 40

3.3 STRATEGIC LANDSCAPE CONTEXT

Leend Leend LCA 17 / LCA 17 Head House T odol Gnedd / Tŷ Fodol site, Gwynedd Head House T odol Gnedd N Anglesey Gwynedd Lndce Crcter Are Gwynedd Lndce Crcter Are C 1 angor Coastal Plan C 1 angor Coastal Plan

C 1 enai Coast C 1 enai Coast LCA 15 LCA 15 C Penisaraun Plateau C Penisaraun Plateau LCA 11 C laneries ethesda LCA 11 C laneries ethesda C Caernaron Coast and Plateau C Caernaron Coast and Plateau Aneey Lndce Crcter Are Gwynedd Aneey Lndce Crcter Are LCA 12 C 11 astern enai trait A55 LCA 12 C 11 astern enai trait C 1 ast Central nglese C 1 ast Central nglese C 1 Western enai trait Bangor C 1 Western enai trait C 1 Nirch C 1 Nirch C 1 on Ceni C 1 on Ceni LCA 1 C 17 West Central nglese A4087 LCA 1 C 17 West Central nglese A55

A55 A5 LCA 16 LCA 13 LCA 16 LCA 13 Landscape Character Area (LCA) 4: Caernarfon-coast and plateau A4080 Landscape Character is assessed at a county level through the Gwynedd Council Supplementary Planning Guidance (SPG) for Landscape Character (2009). A4244 The site area falls within LCA 4, Caernarfon Coast and Plateau a long broad fringe adjacent to the Menai Coast LCA 16, extending to the upland fringes of Moel Tryfan and Mynydd y Cillgwyn influenced by glacial actions and resultant deposits and landforms. There is a mixture of settlement types – small villages to large towns with Caernarfon being an important historicLCA 3 core, with modern settlement edges of varying A487 LCA 3 LCA 14 quality.LCA 2A range of coastal habitats and landscapes, contribute to the character of the LCA 2 LCA 4 area. LCA 14 Some of the eastern and northern parts of the area have been included in the LCA 4 Register of Landscapes of Outstanding Historic Interest in Wales (Dinorwig and the Nantle Valley). In addition, the castle and town walls of Caernarfon are internationally recognised as a World Heritage Site. The area displays a complex mix of historic landscapes of different characters and periods, dominated by 19th century estate farmland with valued areas of parkland remaining (e.g. at Glynllifon). Interspersed 9 9 eters Contains ulic sector inormation licensed under the en Goernment icence . amongst the estate lands are prehistoric remains including ancient hut circles and hillforts. 9 9 eters Contains ulic sector inormation licensed under the en Goernment icence . Local Landscape Character Areas Contains Ordnance Survey data © Crown copyright and database right 100024241(2018)

North Wales Connection Project Tunnel Head House Design Guide Document 7.19 41

3.4 LANDSCAPE DESIGNATIONS The following designated areas have been identified within 5 km of the site

Tŷ Fodol site, Gwynedd

Site of Special Scientific interest- Safeguard the range,quality and variety of habitats, species and geological features in all parts of Wales. The identified sites are: Eithinog; Coedydd Afon Menai; Eryri.

Local Nature Reserve - Coed Cyrnol Nature Reserve is an area of mixed Bangor deciduous, broadleaved and coniferous woodland. Both sets of arborial species encourage rich bird and animal life.

AONB - The coastal zone of Anglesey was designated as an AONB in 1966 and was confirmed in 1967. It is the largest AONB in Wales, covering one third of the island.

Special Landscape Area (SLA) - The site lies in proximity to four SLA. The Vaynol Estate and Surrounds Special Landscape Area, is located on the southern bank of the Menai Strait, covering the Faynol Estate and the wooded grounds surrounding part of the Bangor University campus. Bangor Mountain and Minfford SLA encompasses the undulating farmland around Minffordd to the south and is bounded to the west and north by the city of Bangor, the south by the A55 and the east by an industrial estate and the A5. The North Western Fringes of Snowdonia SLA forms a ‘collar’ around the north and western edges of Snowdonia National Park and stretches from Nasareth in the south-west to Llanllechid in the north-east. On Anglesey the Southern Estatelands SLA adjoins the boundary of the AONB.

Registered Parks and Gardens - 2 Registered Parks - Vaynol Park, Bangor and Plas Newydd; 5 Registered Gardens and 11 Country House Gardens located within the 5 km study area (see page 44)

Ancient Woodland - There are a total of 237 ancient woodland sites spread across the 5 km study area.

Special Areas of Conservation - SACs are internationally important and Local landscape designation map Contains Ordnance Survey data © Crown protected and represent some of the most important sites for wildlife and the copyright and database right 100024241(2018) environment. The identified sites which fall within the 5 km area are: Eryri/ Snowdonia and the Menai Strait and Conwy Bay / Y Fenai a Bae Conwy.

North Wales Connection Project Tunnel Head House Design Guide Document 7.19 42

Map showing Historic Landscape Aspect Areas Map showing Cultural Landscape Aspect Areas Prehistoric Historic Landscape Aspect Areas as defined by Natural Industrial Cultural Landscape Aspect Areas as defined by Natural Resources Resources Wales in the LANDMAP database Wales in the LANDMAP database Roman There are 23 Historic Landscape Aspect Areas falling within Institutions There are 25 Cultural Landscape Aspect Areas falling within the 5 km study the 5 km study area as described below. area as described below. Medieval up to 1536 Infrastructure • Within Gwynedd: Nantile slate quarries; Llanfair Isgaer; • Within Gwynedd: Bangor (Central); Bangor (University); Railway - Chester Post-medieval after 1536 Gwaen Gynfi enclosed area; Bethel & Saron; Northern Urban to Holyhead; Principal roads; Bryn Cegin and Parc Menai industrial Arfon plateau; Afon Rhythallt; Roads; Rhiwlas; Bangor estate; Bangor Mountain/Arfon plateau; Arfon plain; Treborth; Sustrans Rural Industrial mountain; Moel y Ci/Gwaen Gynfi unenclosed uplands; cycle route; y Faenol; y Felinheli; Plas Menai-watersports centre; Quarry Vaynol; Y Felinheli (Port Dinorwic); Llanrug; Hillslopes settlement areas; Unenclosed mountain; and A55. Recent Places below Moel y Ci/Rhiwen; Llanddeiniolen/ Dinorwic; • On Anglesey: A5 Road; A5 Road Villages; A55 road; Railway - Chester Gwaun; and Cegin valley. to Holyhead; Transport corridor area; Menai Bridge; Southern Anglesey • On Anglesey: South Anglesey parkland; Fieldscape Coast – Llandegfan; Sustrans cycle route; Central Anglesey; Plas south of Malltraeth; A5 corridor and associated villages; Newydd, Plas Llanidan. Coastline around Llandegfan; Fieldscape, central eastern * Industrial - minerals & mining, power generation & distribution, heavy industry; Mon; and Menai Bridge. * Institutions - land division, religion, educational movements; * Infrastructure - tourism, services, communication & transport, education & welfare; * Places - sense of place, name of places.

North Wales Connection Project Tunnel Head House Design Guide Document 7.19 43

3.5 SENSITIVE VISUAL AND CULTURAL HERITAGE RECEPTORS Legend Tŷ Fodol Site, Gwynedd

1 Standing Stone Scheduled Monument 2 Holiday Lets 3 Road users along Fodolydd Lane 4 Fodol Ganol Hut Circle Scheduled Monument Nearest residential receptors

Approximate location of standing stone

Views from Standing Stone: Whilst not publicly accessible, views from and effects upon the setting of the Standing Stone have been considered. Views to the east towards the Tŷ Fodol site are generally open, with the field within 4 which the site is located being visible over the top of woodland that is located 3 at the base of a small incised valley. The tops of pylons of the existing 400 kV OHL are visible on the horizon beyond and the mountains of Snowdonia form a backdrop in the view. 2 Views from holiday homes: Long distance views are afforded towards lower lying areas, including Anglesey, to the north. The foreground comprises pastures with hedgerows and individual trees. Landform falls away to the west with views towards the Tŷ Fodol site filtered by existing vegetation. 1 Views from Fodolydd Lane: Views to the Tŷ Fodol site are filtered by vegetation along field boundaries along the narrow lane.

2

N

Contains public sector information licensed under the Open Government Source: Esri, DigitalGlobe, GeoEye, Earthstar Geographics, CNES/Airbus License v3.0 DS, USDA, USGS, AeroGRID, IGN, and the GIS User Community

North Wales Connection Project Tunnel Head House Design Guide Document 7.19 44

3.6 SITE & WIDER CONTEXT ANALYSIS

3.6.1 Site Analysis

The Tŷ Fodol site is located within pastoral fields between properties known as Fodol (200 m), Vodol-isaf/Vodol Cottage (200 m) and Garth Fawr (380 m). To the south of the site is Nant-y-garth, a wooded ravine which contains a landfill site. Views of the proposals from Vodol-isaf/Vodol Cottage would be screened A487 by land form. Views from properties at Fodol A4087 and Garth Fawr of the proposal benefit from some screening from landform. A tributary of the Nant Cefn flows in a westerly direction, approximately 170 m south of the site. The site is located at approximately 80m AOD, on ground which rises to the south-east to approximately 90 m AOD. Vaynol Park 4

1 Scheduled Monument - Standing Stone 5 B4547 (SAMCN375): is located west of the site. Views from this stone have been an important 2 consideration in the design approach A487

2 Access road: The site is bordered by a rural 3 access road called Fodolydd Lane to the north 1 of the site. Views from this road have been considered in the built form articulation and 5 landscape treatments

3 Homestead: Views from this area have been considered in the built form and landscape treatment

4 Vaynol Historic Park and Gardens: is a country estate originating from the Tudor period. There are no direct views into the site from this estate N

5 Slopes: The site is elevated, but even so, due Site Context Analysis Plan Legend to the topography and woodlands, the head Tŷ Fodol site, Gwynedd Main roads Scheduled monuments Overhead lines house would not be directly visible from much Hedgerow network Secondary roads Woodland cover Register gardens Listed Buildings of the surrounding context. Stream / lake Existing settlements Ancient woodland Register parks

North Wales Connection Project Tunnel Head House Design Guide Document 7.19 45

3.6.2 Site and Context Images

Existing site condition View of access road with site to the right View towards Standing Stone from access road AMEC View of fields to the south of the site The standing stone Scheduled Monument to the west of the site Homestead east of the site

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3.6.3 Local Landscape Colours, Materials and Details

During site visits, it was identified that the key influences on the site were both the rural landscape and local estate architecture; these helped inform the design process.

Some of the key features in this character tapestry include:

• green fields with border trees and planting;

• narrow access roads;

• stone fencing;

• slate roofs;

• barn architecture;

• rural pathways;

• pitched roofs;

• timber fencing;

• metal sheet clad walls; and

• compacted mud access routes.

All photographs are taken by Jacobs

North Wales Connection Project Tunnel Head House Design Guide Document 7.19 47

3.6.3 Local Landscape Colours, Materials and Details

Some of the key features in this character tapestry that have been reflected in the design approaches include:

• the standing stone Scheduled Monument denotes the historic significance of this area;

• the rustic complex of Vaynol Vaynol Home Farm Complex Home Farm;

• the grand gateway statement and iconic stone wall of Vaynol Park;

• stone walls;

• rural and agricultural character; and

• woodlands adjoining the Menai Strait.

Vaynol Home Farm Complex

Vaynol Home Farm Complex Vaynol Park Wall All photographs are taken by Jacobs

North Wales Connection Project Tunnel Head House Design Guide Document 7.19 48

3.6.4 Sensitive Sites and Heritage

There has been little archaeological field investigation and is marked on the southern edge by the Snowdon in the vicinity, however a geophysical survey has summit before opening to the gently undulating been undertaken of the Tunnel Head House site Arfon plateau to the north-west. The massive 19th and adjacent land, but little significant evidence for and 20th century slate quarries and their associated settlement was revealed. settlement and transport infrastructure are a defining characteristic of this historic landscape, but there is 400m to the west of the proposed Head House also surviving evidence for late-prehistoric as well as compound there is a scheduled standing stone (SAM medieval land use and settlement. CN375). This is a relatively squat stone, probably erected during the Bronze Age. The adjoining On Anglesey and in Gwynedd, the traditional method photograph shows the monument with the proposed of field boundary construction is common to many site beyond. ‘Celtic’ field systems, the Cloddiau. These are the earth banks, embedded with and faced with stone on There is also at least one prehistoric/Roman enclosed the windward side. The stones used are small and hut circle sentiments. Fodol Ganol Enclosed Hut irregular and would have originally been gathered Group is a scheduled monument (CN175) which by field clearance, but later from quarried material. is located approximately 400m to the east of the Originally the Cloddiau would have been about 1m proposed Tunnel Head House, with a further potential high and 1m wide, and when topped by gorse or AMEC example 130 m to the west. These were sub-circular hedgerow, produced a substantial stock-proof barrier The standing stone Scheduled Monument to the west of the site enclosures, built of stone rubble, each of which to enclose fields and lanes. Crawiau fencing is also would have enclosed a small settlement of 3 to 4 used in this part of Gwynedd, which is characterised roundhouses, and connected into a local landscape of by vertical slate slabs which are usually bound small enclosed fields. together with twisted wire, and may also have a base with irregular stones at the bottom. These typically stand 1 - 1.25 m in height. To the north and west of the Tŷ Fodol site lies the Historic Landscape Aspect Area (HLAA) of Vaynol (GWNDDHL750), comprising the Vaynol estate, which As for the built historic environment, the traditional originated in the medieval period and was the second buildings around Fodol typically incorporate the use largest estate in Caernarvonshire by the middle of the of locally available materials such as slate roofing and 19th century. Enclosing this area to the south is the stone rubble. Many of the buildings were connected to higher ground of the Northern Arfon Plateau HLAA the Vaynol Estate. (GWNDDHL024), much of which is former Vaynol land and includes a series of substantial 19th century farmhouses. The area also contains a number of prehistoric settlement sites including hut groups and small forts.

The area also includes land within the Dinorwig Landscape of Outstanding Historical Interest. This is focused around the Dinorwig valley, or Nant Peris which is located on the north-west side of Snowdonia Vaynol Home Farm

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3.6.5 The Welsh Water Treatment Plant, Garndolbenmaen Case Study

During the stakeholder engagement, officers at Gwynedd Council identified the Water Treatment Plant recently constructed at Garndolbenmaen as an example of how large utility facilities can be designed in a sympathetic way, so as to better accommodate them within the local landscape of Gwynedd. Although the water treatment plant is a significant infrastructure site, the built form articulation and material treatments create a visually appealing campus that does not stand out in a rural, agricultural context.

The stepped pitched roof profiles create visual interest and articulation while also being simple forms that would lend themselves to efficient internal operational areas. The shades

of green in the wall and roofing Water © Welsh materials helps blend the massing into the surrounding agricultural landscape. The wall face is broken up with a visually heavier stone base with a panelled wood finish on the top which creates further visual articulation and helps break up the massing. The surrounding landscape and earth mounding help blend the built form further into the landscape. The massing broken up into parts creates a less monolithic building, creating an agricultural campus style master plan.

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3.7 VISION, DESIGN OPTIONS & PRINCIPLES - TŶ FODOL

3.7.1 Vision and Design Approach

At the initial stakeholder engagement meeting in May 2017, Design Vision the main design theme that emerged is that a design approach The aspiration for the Tunnel Head House at the Tŷ Fodol site is to create a built form reflecting the local vernacular and rural architecture, which is which reflects influences of the local agricultural architecture and blends into the landscape predominantly agricultural in style, would be more in keeping with through appropriate massing, materials, colours and treatments. The building must reflect a this site area. narrative of having grown over time through a series of massing, a mosaic of treatments and articulation. The design narrative of an agricultural farmstead that has extended gradually over time, formed through various extensions, hence varied massing, materials and roof profiles, was considered an interesting narrative to take forward. N The use of a mix of forms, materials and roof profiles to create a more broken up massing, while being mindful of the internal View from ac- operational requirements, was considered a key design cess road approach. View from Homestead

View from the Stand- ing Stone Tunnel Shaft © Welsh Water © Welsh

Massing and View Influences • The key massing design approach was to move ancillary and welfare units to the front of the site to achieve lower built form to the front elevation, and step the higher ventilation unit to the back; and • Views from the Standing Stone, nearby residences and holiday lets have been a key consideration. The massing and roof profiles step down towards these views to achieve further articulation and to break up the massing.

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Tŷ Fodol Site Building Functional Design

This page shows the minimum functional engineering design elevations for the Tŷ Fodol Head House. This would have been the basic design that would usually

0 be used for such100 head houses. The preferred200 design 300 attempts to articulate this massing to respond to the sensitive views and character areas around the site.

2 4 1 5 3 0003 0003 0003 0003 0003 1 2 3 C B A

36550 23000

Indicative Roof Indicative Roof

NVD 1 3535 7070 7070

NVD 2 NVD 3 3535

Elevation 3 Elevation 4 1 : 100 1 : 100

4 2 3 1 0003 0003 3 0003 2 0003 1 A B C

36550 23000

Indicative Roof Indicative Roof

Louvre Louvre 7070

7070 Roller Shutter Roller Shutter

This is a conceptual design only and would have been subject to Elevation 1 Elevation 2 1 : 100 1 : 100 further structural design in the detailed stages.

Mott MacDonald Ltd, Victory House, Trafalgar Place, Brighton, BN1 4FY

nationalgrid National Grid plc, Warwick Technology Park, Gallows Hill, Warwick, CV34 6DA Title Gwynedd Headhouse Elevations Headhouse Building NOTES Gwynedd - Ty Fodol 1. DO NOT SCALE FROM THIS DRAWING. ISSUENorth WalesP02 Connection2. DRAWING ProjectTO BE READ IN CONJUNCTION WITH RELEVANT SHAFT, TUNNEL, CIVIL AND ELECTRICAL DRAWINGS. 3. HEADHOUSE STRUCTURE IS NOT DESIGNED AND SHOWN INDICATIVELY Site 4. HEADHOUSE CLADDING / BUILDING ENVELOPE IS NOT DESIGNED AND SHOWN INDICATIVELY Wyfla - Pentir A1 DRAWN ZP Originator Drawing Number 356526 - MMD - 03 - ZZ - DR - A - 0002 CAD CHECKED TD NG Drawing Number Sheet No. No. of Sheets ISSUE 0002 P02 APPROVED/DATE AF 12/05/17

PRELIMINARY ISSUE PRELIMINARY SCALE:- National Grid plc owns the Copyright of this Document. It may not be reproduced or transmitted in any form or for any purpose, without the express written permission of National Grid plc Tunnel Head House Design Guide Document 7.19 52

3.7.2 Tŷ Fodol Site Building Form Preferred Option and Key Design Principles

In August 2017, four design options (as outlined on pages 54-57) were presented to officers from Gwynedd Council. Based on the feedback, a revised version of Options 1 & 3 has emerged as National Grid’s preferred design approach with the following key design principles: 5 6

Key Design Principles 4 1• The building volume would not exceed 9,300 m³ with a maximum building height of 11 m 2 2• Ancillary and welfare rooms placed to the front of 3 View from standing stone the site to create a lower built form towards the front facade 3• Access rooms and smaller ventilation units may be placed on a mezzanine level to create a higher 7

built form. There are potential opportunities to View point further reduce massing by removing or reducing the mezzanine level and increasing the footprint within the constraints imposed by the DCO parameters Standing Homestead 4• The fan room placed at the back of the site as the Stone taller mass View from Access Road Location Plan 5• The higher elements have pitched roofs that step down towards the Standing Stone 6• Metal standing seam roof with muted grey or green colour suggested View from Homestead This architectural sketch provides an illustrative means of interpreting the Key Design Principles. The final Tunnel 7• Wall massing broken into sections where the lower Head House is likely to differ somewhat in form and scale within the parameters of the DCO. section could be in visually heavy stone finishes or concrete, while the upper section could be External safety and maintenance equipment including Fall Arrest system at roof height are likely to be provided. corrugated metal, concrete panels, wood-effect panels or striated cladding in muted green or grey tones. Additional recesses could be provided to enhance visual articulation. © Welsh Water © Welsh © RHEINZINK

North Wales Connection Project Tunnel Head House Design Guide Document 7.19 53

The below architectural sketches provide an illustrative means of interpreting the Key Design Principles. The final Tunnel Head House is likely to differ somewhat in form and scale within the parameters of the DCO. View from Homestead External safety and maintenance equipment including Fall Arrest system at roof height are likely to be provided.

View from standing stone Oblique view from the south west showing façades towards the standing stone and Coed Nant Y Garth.

View from standing stone

Oblique view from the north west showing façades towards the standing stone and Fodolydd Lane operational access

North Wales Connection Project Tunnel Head House Design Guide Document 7.19 54

3.7.3 Tŷ Fodol Site Building Form Initial Option 1

The first option focused on breaking up the massing of the building into four parts with distinct roof forms while breaking up the walls with a mix of materials.

Design features

1• Ancillary and welfare rooms placed to the front of the site to create a lower built 3 View from standing stone form 2• Access rooms and smaller ventilation 7 units placed in a higher built form, creating a step up 4 3• The fan room placed at the back of the 1

site as the biggest mass, but steps down View point towards the Standing Stone 2 4• Stepped, pitched roofs reflect the slope of mountains to use backgrounding and 6 Standing Homestead to reduce light reflection Stone

5• Wall massing broken into sections with 5 Location Plan lower section with visually heavy stone finishes while the upper section could View from Access Road be wood panelling (subject to fire safety design) or metal cladding in muted green or grey tones

6• Additional fenestration, over what is View from Homestead required for operational purposes to enhance visual articulation 7• The front roofs could be of slate-effect panels while higher roofs could be metal sheets with muted grey or green colour. © Welsh Water © Welsh © RHEINZINK

North Wales Connection Project Tunnel Head House Design Guide Document 7.19 55

3.7.4 Tŷ Fodol Site Building Form Initial Option 2

This option explored varying the roof forms with pitched and vaulted roofs with stepped articulation towards sensitive sites.

Design features

•1 Ancillary and welfare rooms placed to the front of the site to create a lower built form

•2 Vaulted roofs for the back elements 2 3 View from standing stone containing the ventilation units to create further massing distinction and suggest a 3 barn like architecture 7 •3 Roofs stepped and lowered towards the 6 Standing Stone and homestead with 4 1 holiday homes to create visual articulation •4 Pitched roofs with a channel feature in the middle and panelling along the gable end 5 with wood-effect panels or metal sheets

•5 Wall massing broken with fenestration and View from Homestead View from Access Road panelling in wood-effect panels, formed concrete, metal, brick or slate waste View point •6 Louvres and panels along facade visible from homestead to suggest a barn style façade Standing Homestead Stone •7 Panelling with wood-effect panels, formed concrete or metal with muted tones to Location Plan break up massing and suggest barn style architecture.

North Wales Connection Project Tunnel Head House Design Guide Document 7.19 56

3.7.5 Tŷ Fodol Site Building Form Initial Option 3

This option explored further articulation of varied roof forms and massing.

Design features

1• Ancillary and welfare rooms placed to the front of the site to create a lower built form. Potential for a more domestic homestead style facade treatment with View from standing stone wood-effect panels and slate-effect roofs 3 2• Smaller fan unit room stepped higher with clerestory windows along the roof to 4 give a distinct identity and more natural 1 light internally. Panelling with wood-effect 6 panels or metal along roof line 5 2 3• The fan room as the highest mass with roofs stepping down towards the Standing Stone and homestead 4

View point 4• Low rise pitched roofs along the back elements, stepped for additional articulation View from Homestead • Additional fenestration and architecturally Standing Homestead 5 Stone enhanced louvres to break up the façades View from Access Road

Location Plan 6• The front roofs could be of slate-effect panels while higher roofs could be metal sheets with muted grey or green colour.

North Wales Connection Project Tunnel Head House Design Guide Document 7.19 57

3.7.6 Tŷ Fodol Site Building Form Initial Option 4

At the initial stakeholder engagement meeting it was suggested that curved roofs are not common in the agricultural context of this area. View from standing stone However, there was an interest in a curved roof example that was tabled as it seemed to be an interesting profile and blended into the mountainous background. Hence this has been included as a sketch option. View from Homestead This is a not a preferred option for National Grid due to cost and maintenance concerns. View from Access Road It is likely to also appear incongruous in the View point local context, presenting a very modern form of roof design.

Standing Homestead Stone

Location Plan

Sketch showing potential to use curved roofs

Sketch of example shown at the initial stakeholder engagement meeting

North Wales Connection Project Tunnel Head House Design Guide Document 7.19 58

3.8 Landscape Design Approach

The landscape setting and design approach to the Tŷ Fodol Tunnel Head House and Cable Sealing End Compound is as follows:

• the site is located within pastoral fields between properties known as Fodol (200 m), Vodol-isaf/ Vodol Cottage (200 m) and Garth Fawr (380 m); • to the south of the site is Nant-y-garth, a wooded ravine which contains a landfill site; • views of the proposals from Vodol-isaf/Vodol Cottage screened by land form; • views from properties at Fodol and Garth Fawr of the proposal benefit from some screening from landform; • proposed planting and mounding will provide additional screening from properties at Fodol and Garth Fawr of the site; • proposed new hedgerow, crawiau and slate pillar fencing to reinstate northern boundary edge; • the attenuation pond would be designed as a part of the landscape setting of the site; • land boundary fronting Fodolydd Lane could be reinstated with Crawiau to reinforce local landscape character; • planting mixes to comprise largely indigenous species with both deciduous and evergreen components to provide year round screening and bio-diversity benefits; and • locally appropriate wild flower seeding mixes to be used to provide interest and bio-diversity benefits for invertebrates.

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Landscape Masterplan Imagery ©2018, Map data ©2018 Google

North Wales Connection Project Tunnel Head House Design Guide Document 7.19 59

3.9 Photomontages

The adjoining photomontages show the existing and proposed view of the Tŷ Fodol Tunnel Headhouse and CSEC within the surrounding site context.

As shown in these images, the built form is set back from the boundaries and surrounded by landscape treatments which mitigate any visual impacts on sensitive views from the surrounding context.

The articulation of the built form and the use of materials and colours as discussed in the Design Guide would present a visually appropriate built form within a landscape setting in this context. Aerial Imagery provided by National Grid View of existing Site Aerial Imagery provided by National Grid View of proposed built form and landscape treatments

North Wales Connection Project Tunnel Head House Design Guide Document 7.19 60

1 2 Photomontages 1• View from the north of the site showing the building in the landscape setting. 2• View from the north showing the head house and the attenuation pond.

3• View from the north east showing the variation in massing and materials as well as the landscape setting. 4• View from the west showing how the built form steps down towards the standing stone. 5• View from the north showing the variation in massing and materials.

6• View of the front facade showing the lower form 3 4 of the ancillary and welfare rooms.

7• View showing head house from the north with a variation in roof colour. The Juniper Green roof colour may help blend the built form into the landscape from distant views. The landscaping is shown at year 15. Electrical plant and equipment omitted for clarity.

5

6 7

North Wales Connection Project Tunnel Head House Design Guide Document 7.19 61

3.10 MATERIALS PALLET

3.10.1 Built Form

H

A B C D H

F Welsh Water Welsh

© E G I A wood-effect cladding and stone facade B steel facade C stone base with metal panelling above © duch mill supply D formed concrete panelling E example of how stepped roofs, mix of materials, panelling and green tones help improve visual impact of buildings F metal roof © eric hands, flickr G metal standing seam roof © rheinzink H fine grain louvres © colt int. ltd Indicative colour palette I example of dark coloured brick base and metal panels above © colt int.ltd

North Wales Connection Project Tunnel Head House Design Guide Document 7.19 62

3.10.2 Access and Surface Treatments

G

A B C D

H

F

E J I

A pebble stones F bodpave85 porous pavers © terram.com B buff-grey self-binding gravel G coloured asphalt with green chippings © pavingexpert.com C slate chippings H blue grey slate chippings D grass crete I gabion wall with waste slate © smallwood-gabion.co.uk E tar-macadam surface J coloured asphalt © aggregate.com

North Wales Connection Project Tunnel Head House Design Guide Document 7.19 63

3.10.3 Traditional Fencing & Secure Fencing

A C

B D A crawiau style boundary B cloddiau style boundary fence C galvanised palisade fence for secure compounds D stock fencing © jonrichardscontracting.co.uk

North Wales Connection Project Tunnel Head House Design Guide Document 7.19 64 4.0 Pentir, Gwynedd 4.1 SITE ANALYSIS

Pentir 400kV substation is an existing high voltage transmission network substation owned and operated by National Grid. The site analysis explored the following key features in the surrounding context:

1• Pentir Site Office: is located west of Tŷ Fodol 3 the site and is a current site office for Site National Grid

2• Key access road: An access road off the B4547 is the key access into the site

3• Tŷ Fodol Site: is located north west of the site 4

4• Woodland cover: The site is currently enclosed by woodland cover which 1 Pentir Site provides visual screening. Office B4547 2

A4244 N

Site Context Analysis Plan Legend Pentir site area, Gwynedd Main roads Existing settlements Secondary roads Proposed extension Woodland cover Overhead lines

North Wales Connection Project Tunnel Head House Design Guide Document 7.19 65

4.2 PENTIR 400 KV SUBSTATION TECHNICAL DESIGN

7 9 Pentir 400kV substation is an existing high voltage transmission network substation owned and 3 operated by National Grid. Substations are a method of controlling power flows and voltages 10 across the transmission system and between the transmission and distribution systems. 9 As part of the Works, the existing substation is to be extended to the north west and south east 11 to facilitate the transmission of additional generation over the high voltage transmission network. The design of the extension is largely driven by functional requirements. The proposed electrical equipment is largely installed outdoors, on a levelled development site. Opportunities to vary the siting and spacing of equipment across the site are extremely limited. The live equipment needs to 10 be enclosed by effective security fencing, which also encloses internal access roads. The following is a list of additional equipment types being installed as part of the extension:

1• Circuit Breaker: interrupts power flow. the Transmission Network. Material: mixture Materials: mixture of metal body and silicone/ of metal body and silicone or porcelain 12 porcelain insulators insulators

2• Post Insulators: Support HV conductors to 7• Full Line Tension Gantry and Line Landing keep them away from the earth. Typically Gantry (400kV): The overhead line conductors 8 porcelain insulators above a steel structure terminate on this structure. Materials: Steel 11 9 3• Cable Sealing Ends (400kV): interface 8• Shunt Reactor (400kV): Shunt Reactors 10 between air insulated conductor (busbar / are used to control the voltage on the 11 OHL conductor) and underground cables, Transmission Network within licence limits. one required per cable. Typically a silicone Materials: Steel insulator above a steel structure 3 9• Security Fencing: The security fencing is 12 6 • Disconnector (400kV): Capable of a 2.4 metre high galvanised steel palisade 7 4 2 5 4 disconnecting the line from the substation fence with a 4m high (from ground level) 1 (safety precautions). Materials: mixture of electric fence backing 4 metal body and silicone or porcelain insulators 10• Substation roads: Tarmac / asphalt surface. • Earth Switch/Post Insulator (400kV): To apply Required to move plant and persons around 5 N

safety precautions for work on this equipment the site and to access equipment Imagery ©2018, Map data ©2018 Google and supports HV conductor to keep it away from earth. Typically porcelain insulator above 11• Substation surfacing: The substation surfacing a steel structure is stone chippings

• Current and Voltage Transformers (400kV): 6 12• Ancillary plant rooms / relay rooms: These Provide measurements of voltage and house the protection and control, low voltage current for use in the protection and control of power and signalling equipment required to operate the substation. Material: prefabricated steel or brick. Palisade fence Existing relay room

North Wales Connection Project Tunnel Head House Design Guide Legend / Allwedd Document 7.19 66

TYPICAL TYPICAL TYPICAL SINGLE POLE POST INSULATOR EARTH SWITCH SINGLE VOLTAGE TRANSFORMER

Notes / Nodiadau

1. THIS DRAWING IS SCALED AT PAPER SIZE A1, THEREFORE ANY PRINTS TAKEN AT SMALLER SIZES WILL AFFECT ACCURACY OF THE MEASUREMENT UNITS AND SHOULD NOT BE SCALED AGAINST. 2. WHERE A SINGLE ITEM OF EQUIPMENT IS SHOWN, THIS WOULD NORMALLY BE INSTALLED IN A GROUP OF THREE.

THE NATIONAL GRID (NORTH WALES CONNECTION PROJECT) ORDER DESIGN PLAN: ILLUSTRATIVE SUBSTATION EQUIPMENT REGULATION 5(2)(o) SHEET 6 OF 9 GORCHYMYN NATIONAL GRID (PROSIECT CYSYLLTIAD GOGLEDD CYMRU) CYNLLUN DYLUNIO: DARLUN O OFFER YR TYPICAL TYPICAL TYPICAL ISORSAF DISCONNECTOR WITH EARTH SWITCH SINGLE CURRENT TRANSFORMER SINGLE CIRCUIT BREAKER RHEOLIAD 5(2)(o) DALEN 6 O 9 Examples of typical equipment

Application Number / Rhif y Cais EN020015

National Grid Drawing Reference / Cyfeirnod Lluniad National Grid DCO_DE/PS/01

THIS PLAN IS ILLUSTRATIVE. ANY DIMENSIONS ARE TYPICAL OR ILLUSTRATIVE DIMENSIONS. ACTUAL APPARATUS MAY DIFFER IN STYLE, MODEL AND SIZE. CYNLLUN DARLUNIADOL YN UNIG YW HWN. DIMENSIYNAU ARFEROL NEU DDARLUNIADOL A NODIR YMA. MAE’N BOSIB Y BYDD Y CYFARPAR GO IAWN YN WAHANOL O RAN ARDDULL, MODEL A MAINT. N/A A1 SHEET 6 OF 9 A North Wales Connection Project Legend / Allwedd

Tunnel Head House Design Guide Document 7.19 67

TYPICAL TYPICAL Notes / Nodiadau 1. THIS DRAWING IS SCALED AT PAPER SIZE A1, THEREFORE ANY PRINTS TAKEN AT SMALLER SIZES WILL AFFECT ACCURACY OF THE MEASUREMENT UNITS AND GANTRY FULL TENSION GANTRY SHOULD NOT BE SCALED AGAINST.

THE NATIONAL GRID (NORTH WALES CONNECTION PROJECT) ORDER DESIGN PLAN: ILLUSTRATIVE SUBSTATION EQUIPMENT REGULATION 5(2)(o) SHEET 7 OF 9 GORCHYMYN NATIONAL GRID (PROSIECT CYSYLLTIAD GOGLEDD CYMRU) CYNLLUN DYLUNIO: DARLUN O OFFER YR ISORSAF RHEOLIAD 5(2)(o) DALEN 7 O 9 TYPICAL

PORTABLE RELAY ROOM Application Number / Rhif y Cais EN020015

National Grid Drawing Reference / Cyfeirnod Lluniad National Grid DCO_DE/PS/01 Examples of typical equipment THIS PLAN IS ILLUSTRATIVE. ANY DIMENSIONS ARE TYPICAL OR ILLUSTRATIVE DIMENSIONS. ACTUAL APPARATUS MAY DIFFER IN STYLE, MODEL AND SIZE. CYNLLUN DARLUNIADOL YN UNIG YW HWN. DIMENSIYNAU ARFEROL NEU DDARLUNIADOL A NODIR YMA. MAE’N BOSIB Y BYDD Y CYFARPAR GO IAWN YN WAHANOL O RAN ARDDULL, MODEL A MAINT. N/A A1 SHEET 7 OF 9 A

North Wales Connection Project Legend / Allwedd THE NATIONAL GRID (NORTH WALES CONNECTION PROJECT) ORDER DESIGN PLAN: ILLUSTRATIVE SUBSTATION EQUIPMENT REGULATION 5(2)(o) SHEET 8 OF 9 Tunnel Head House Design Guide Document 7.19 68

TYPICAL SHUNT REACTOR Notes / Nodiadau 1. THIS DRAWING IS SCALED AT PAPER SIZE A1, THEREFORE ANY PRINTS TAKEN AT SMALLER SIZES WILL AFFECT ACCURACY OF THE MEASUREMENT UNITS AND SHOULD NOT BE SCALED AGAINST. 2. WHERE A SINGLE ITEM OF EQUIPMENT IS SHOWN, THIS WOULD NORMALLY BE INSTALLED IN A GROUP OF THREE.

THE NATIONAL GRID (NORTH WALES CONNECTION PROJECT) ORDER DESIGN PLAN: ILLUSTRATIVE SUBSTATION EQUIPMENT REGULATION 5(2)(o) SHEET 8 OF 9 GORCHYMYN NATIONAL GRID (PROSIECT CYSYLLTIAD GOGLEDD CYMRU) CYNLLUN DYLUNIO: DARLUN O OFFER YR ISORSAF RHEOLIAD 5(2)(o) DALEN 8 O 9

TYPICAL TYPICAL TYPICAL THREE PHASE POST INSULATOR Application Number / Rhif y Cais SINGLE SURGE ARRESTOR SINGLE CABLE SEALING END SINGLE PANTOGRAPH DISCONNECTOR EN020015 National Grid Drawing Reference / Cyfeirnod Lluniad National Grid DCO_DE/PS/01 Examples of typical equipment THIS PLAN IS ILLUSTRATIVE. ANY DIMENSIONS ARE TYPICAL OR ILLUSTRATIVE DIMENSIONS. ACTUAL APPARATUS MAY DIFFER IN STYLE, MODEL AND SIZE. CYNLLUN DARLUNIADOL YN UNIG YW HWN. DIMENSIYNAU ARFEROL NEU DDARLUNIADOL A NODIR YMA. MAE’N BOSIB Y BYDD Y CYFARPAR GO IAWN YN WAHANOL O RAN ARDDULL, MODEL A MAINT. N/A A1 SHEET 8 OF 9 A

North Wales Connection Project Tunnel Head House Design Guide Document 7.19 69

4.3 LANDSCAPE DESIGN APPROACH

As part of the proposed development, an extension is required at Pentir Substation. The extension is predominantly to the south where there is currently an area of woodland which screens the existing substation. After completion of the works at the substation, a landscape mitigation scheme would be implemented which includes the following: • land to the east of the southern extension would be raised to provide partial screening of the site when viewed from the minor public road and property to the south east; • areas of woodland retained around the substation would be brought into National Grid ownership to secure the existing screening these afford; • woodland areas removed to facilitate construction (e.g. construction accesses) would be reinstated; • new woodland planting to the southeast to replace the vegetation lost and restore the screening of the substation, particularly important for those more elevated residential areas to the south which have views towards the substation; • new woodland planting to the north to reinforce the existing screening belt and provide replacement of vegetation removed during construction of the proposed 400 kV overhead line; and • new boundary treatments along the minor road to the north including the introduction of hedgerow planting and fencing treatments such as slate pillar fencing.

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Landscape Masterplan Imagery ©2018, Map data ©2018 Google

North Wales Connection Project Tunnel Head House Design Guide Document 7.19 70 5.0 Conclusion 5.1 DCO REQUIREMENTS AND APPROVAL PROCESS

The development of the Braint and Tŷ Fodol Tunnel Head Houses, and the extension of the Pentir Mitigation planting scheme Substation would be authorised through the confirmation of a Development Consent Order for the DCO Requirement 9 confirms arrangements for necessary planting, including preparation of a North Wales Connection, which includes these elements of work. The final design of the buildings planting scheme for each stage of the authorised development unless otherwise agreed with the and landscaping works would therefore be controlled through mechanisms and Requirements relevant planning authority. contained within any final Order. Implementation of mitigation planting scheme Schedule 3 of the draft Development Consent Order (Document 2.1) sets out 19 draft DCO Requirement 10 is concerned with the implementation of the mitigation planting scheme and Requirements corresponding to conditions which could have been imposed on the grant of defines timescales. planning permission for the works had they fallen within the ambit of normal local development control. The requirements have a similar purpose to planning conditions. There are six draft Maintenance of implemented mitigation planting scheme Requirements that are relevant to the Design approach to be taken. DCO Requirement 11 concerns the period over which planting associated with the mitigation planting scheme is maintained. Planting of damaged or diseased trees are to be replaced by trees Design and Parameters of the same size and species, unless otherwise agreed with the relevant planning authority. DCO Requirement 3 provides that the authorised development shall be carried out in general accordance with the design drawings, so as to allow a necessary but proportionate degree of Retention and protection of existing trees and hedgerows flexibility in the construction of the important and nationally significant infrastructure project.The DCO Requirement 12 ensures the preparation of a Tree and Hedgerow Protection Strategy for exception to this is where any departure from the design drawings gives rise to any materially new each stage, with relevant works not to commence until the approved protection measures are in or different environmental effects from those assessed in the environmental statement. place.

The design drawings are a mixture of parameters, indicative detail, and illustrative detail, as In summary, the following pages presents the key design principles for the Braint and Tŷ Fodol appropriate, therefore, the construction can only be in general accordance with the information Tunnel Head Houses, as referenced in draft DCO Requirement 4. shown on them.

Tunnel Head House Design DCO Requirement 4 provides that the above ground elements of the authorised development within Work No. 8 (Braint and Tŷ Fodol Tunnel Head Houses) shall be carried out in general accordance with the key design principles of the Tunnel Head House Design Guide, unless otherwise agreed with the relevant planning authority. Such an approach accommodates necessary but proportionate flexibility in the construction of these elements.The flexibility to have the relevant planning authority approve a variation to the key design principles is necessary to allow for any departure from the key design principles subject to such approval.

North Wales Connection Project Tunnel Head House Design Guide Document 7.19 71

5.2 BRAINT SITE BUILDING FORM PREFERRED OPTION AND KEY DESIGN PRINCIPLES

In August 2017, three design options (as outlined on pages 28-30) were presented to the key stakeholder group at the Isle of Anglesey County Council. Based Key view from Star on the feedback from that group, a revised version of Option 3 has emerged as National Grid’s preferred View from Homestead design approach with the following key design 3 principles:

Key Design Principles 2 1• The building volume would not exceed 4350 m³ with a maximum building height of 8 m • Front massing to be designed as a high element with 5 2 4 a low pitch gable roof, with slate-effect panel roofing 6 and short overhang, reminiscent of Plas Newydd Home Farm architecture 7 3• Vaulted roofs with corrugated metal for rear Star sections to reduce the visual impact that pitched roof reflections could have for views from Star. The View point mass closest to Star may be lowered further to provide visual articulation depending on functional

constraints Access Route 4• Louvres could be architecturally enhanced through Homestead a suitable colour palette, detailing etc. The physical dimension of the louvres would largely be dictated by View from Access Road Bryn Celli Ddu operational considerations such as air flow rates and Location Plan noise attenuation. Potential for stone or dark brick This architectural sketch provides an illustrative means of interpreting the Key Design Principles. The finalTunnel lintels to reflect local architecture depending on cost Head House is likely to differ somewhat in form and scale within the parameters of the DCO. and functional viability External safety and maintenance equipment including Fall Arrest system at roof height are likely to be provided. 5• The use of smaller recesses would add visual interest to the façade 6• Building facade to be broken with visually heavy stone walls or cladding along the bottom half and linear metal or wood-effect, striated cladding for the top half

7• Potential to transition stone base to metal cladding on side elevations reminiscent of old farms and as a cost efficient design. AMEC Llwyn-onn Farm Sketch of Plas Newydd Home Farm Example of vaulted rural architecture

North Wales Connection Project Tunnel Head House Design Guide Document 7.19 72

5.3 TŶ FODOL SITE BUILDING FORM PREFERRED OPTION AND KEY DESIGN PRINCIPLES

In August 2017, four design options (as outlined on pages 54-57) were presented to officers from Gwynedd Council. Based on the feedback, a revised version of Options 1 & 3 has emerged as National Grid’s preferred design approach with the following key design principles: 5 6

Key Design Principles 4 1• The building volume would not exceed 9,300 m³ with a maximum building height of 11 m 2 2• Ancillary and welfare rooms placed to the front of 3 View from standing stone the site to create a lower built form towards the front facade 3• Access rooms and smaller ventilation units may be placed on a mezzanine level to create a higher 7

built form. There are potential opportunities to View point further reduce massing by removing or reducing the mezzanine level and increasing the footprint within the constraints imposed by the DCO parameters Standing Homestead 4• The fan room placed at the back of the site as the Stone taller mass View from Access Road Location Plan 5• The higher elements have pitched roofs that step down towards the Standing Stone 6• Metal standing seam roof with muted grey or green colour suggested View from Homestead This architectural sketch provides an illustrative means of interpreting the Key Design Principles. The final Tunnel 7• Wall massing broken into sections where the lower Head House is likely to differ somewhat in form and scale within the parameters of the DCO. section could be in visually heavy stone finishes or concrete, while the upper section could be External safety and maintenance equipment including Fall Arrest system at roof height are likely to be provided. corrugated metal, concrete panels, wood-effect panels or striated cladding in muted green or grey tones. Additional recesses could be provided to enhance visual articulation. © Welsh Water © Welsh © RHEINZINK

North Wales Connection Project Tunnel Head House Design Guide Document 7.19 73

North Wales Connection Project

MENT U C O D 7.6

Design Approaches to Proposed Tunnel Head Houses

National Grid (North Wales Connection Project)

Regulation 5(2)(q) of the Infrastructure Planning (Applications: Prescribed Forms and Procedure) Regulations 2009

August 2017