Visual Impact Provision (VIP), Snowdonia Project
Appendix 4: Outline Construction Traffic Management Plan (CTMP)
Visual Impact Provision (VIP) Snowdonia Project
Outline CEMP Appendix 2A: Outline Construction Traffic Management Plan
National Grid Electricity Transmission Plc
Project reference: Snowdonia VIP Project number: 60566917
December 2019
Snowdonia Visual Impact Provision (VIP) Snowdonia Project Project reference: Snowdonia VIP Project number: 60566917
Quality information
Prepared by Checked by Verified by Approved by
L Peaker L Jones Duncan Carter J Reader Consultant Senior Consultant Principal Consultant Regional Director
Revision History
Revision Revision date Details Authorized Name Position V1.0 04/02/2019 1st Issue A Leary Associate Director
V1.1 27/02/2019 Updated Project Description for A Leary Associate Tender Director
V1.2 03/07/2019 Updated to reflect most recent A Leary Associate design information provided Director
V1.3 19/07/2019 Advanced copy: Not for A Leary Associate Planning Director
V1.4 24/07/2019 Following Project Team A Leary Associate Comments Director
V2.0 08/11/2019 For Planning J Reader Regional Director
Prepared for: National Grid Electricity Transmission Plc AECOM
Snowdonia Visual Impact Provision (VIP) Snowdonia Project Project reference: Snowdonia VIP Project number: 60566917
Prepared for: National Grid Electricity Transmission Plc 1 - 3 Strand London WC2N 5EH
Prepared by: Luke Peaker Consultant
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© 2019 AECOM Limited. All Rights Reserved. This document has been prepared by AECOM Limited (“AECOM”) for sole use of our client (the “Client”) in accordance with generally accepted consultancy principles, the budget for fees and the terms of reference agreed between AECOM and the Client. Any information provided by third parties and referred to herein has not been checked or verified by AECOM, unless otherwise expressly stated in the document. No third party may rely upon this document without the prior and express written agreement of AECOM.
Prepared for: National Grid Electricity Transmission Plc AECOM
Snowdonia Visual Impact Provision (VIP) Snowdonia Project Project reference: Snowdonia VIP Project number: 60566917
Table of Contents
1. Introduction ...... 7 Background and Scope ...... 8 CTMP Objectives ...... 9 Scoping and Consultation ...... 10 Study Area ...... 11 Project Timescales ...... 11 2. Construction Vehicle Classification ...... 12 3. Construction Traffic Routes ...... 13 Road Hierarchy ...... 13 Strategic Road Network ...... 13 Local Road Network ...... 13 Temporary Access Tracks ...... 13 Routing Strategy ...... 14 Highways Constraints and Considerations ...... 15 Contingency Routes ...... 17 Workforce Travel & Parking ...... 17 4. Construction Traffic Access ...... 18 Access Locations ...... 18 Project Phasing: Temporary and Permanent Access ...... 18 Access to Tunnel Head Houses ...... 21 Access to Sealing End Compounds (SECs) ...... 21 OHL Removal ...... 21 Conductor Removal ...... 21 Scaffolding ...... 21 Strategic Road Network Crossings ...... 21 Local Road Network Crossings ...... 22 Railway Line Crossings ...... 22 Visibility Splays...... 22 Temporary Access Tracks ...... 22 Operational Traffic Access ...... 22 Access Summary ...... 23 5. Traffic Management ...... 26 Construction Traffic Routes and Access Signage ...... 27 Temporary Access Track Signage ...... 27 Location-Specific Traffic Management ...... 27 Garth Tunnel Head House And SEC ...... 28 A487/ Pont Briwet/ Cambrian View ...... 28 Temporary Road Closures and Diversions ...... 29 Working Hours...... 29 6. Non-Motorised Users ...... 31 Public Rights of Way ...... 31 Wales Coast Path & Other Recreational Routes ...... 32 Cycle Routes ...... 32 NCR8 ...... 32 NCR82 ...... 33 Mitigation for Non-Motorised Users ...... 33 7. Mitigation Measures ...... 34 Proposed Mitigation Measures ...... 34 Location Specific Mitigation Measures ...... 37
Prepared for: National Grid Electricity Transmission Plc AECOM
Snowdonia Visual Impact Provision (VIP) Snowdonia Project Project reference: Snowdonia VIP Project number: 60566917
8. Monitoring and Review ...... 38 Communication ...... 38 Compliance, Enforcement, and Corrective Measures ...... 38 Annex A: AIL Report ...... 39
Prepared for: National Grid Electricity Transmission Plc AECOM
Snowdonia Visual Impact Provision (VIP) Snowdonia Project Project reference: Snowdonia VIP Project number: 60566917
Tables
Table 1-1: Figures ...... 7 Table 1-2: Location of Project Components ...... 8 Table 1-3: Objectives of the Outline CTMP ...... 9 Table 2-1: Project Vehicle Classification ...... 12 Table 3-1: Road Hierarchy ...... 13 Table 3-2: Project Link References ...... 14 Table 3-3: Road Network Constraints and Considerations ...... 16 Table 4-1: Construction Access Schedule ...... 19 Table 4-2: Operation: Typical Maintenance and Inspection Activities ...... 22 Table 4-3: Project Elements: Construction and Operation Access ...... 24 Table 6-1: PRoW Interaction with Proposed Project ...... 31 Table 6-2: ATC Cyclist Data - NCR8 (Link Ref 3) ...... 32 Table 7-1: Mitigation Measures ...... 34 Table 7-2: Proposed Mitigation During Construction ...... 37
Insets
Inset 1: Potential HGV Routing via Cambrian View ...... 29
Prepared for: National Grid Electricity Transmission Plc AECOM
Snowdonia Visual Impact Provision (VIP) Snowdonia Project Project reference: Snowdonia VIP Project number: 60566917
1. Introduction
1.1 This Outline Construction Traffic Management Plan (Outline CTMP) has been prepared on behalf of National Grid Electricity Transmission (plc) (National Grid) for the Visual Impact Provision (VIP) Snowdonia Project (here on referred to as the ‘Proposed Project’).
1.2 A full description of the Proposed Project is provided in Chapter 2 of the Environmental Appraisal. This Outline CTMP should be read alongside Traffic and Transport Chapter 12 of the Environmental Appraisal and the Figures listed in Table 1-1.
1.3 This Outline CTMP describes and explains the approach undertaken to manage and mitigate the impacts of construction traffic arising from the Proposed Project, with specific reference to the construction and access strategy; the ‘embedded mitigation’ incorporated into the design of the Proposed Project and described in the Environmental Appraisal (Traffic and Transport Chapter 12).
1.4 Furthermore, the full list of measures presented in this report – the proposed mitigation during construction – has been informed by the findings of the assessment of construction traffic impacts carried out in the Environmental Appraisal Traffic and Transport Chapter 12. Subsequently, this Outline CTMP sets out the location-specific mitigation measures proposed alongside more generic mitigation measures to be adopted across the Proposed Project.
1.5 The recommendations within this Outline CTMP would be implemented by National Grid and the appointed contractor irrespective of an identified need from the Environmental Appraisal; rather, they are proposed to ensure that the impacts of construction traffic on the local community and other road users are minimised as far as reasonably practicable.
1.6 Table 1.1 lists the Figures referred to within this document, associated with the Environmental Appraisal.
Table 1-1: Figures Figure Environmental Appraisal Chapter Title Reference
2.1 Project Description Construction
2.2 Project Description Operation
12.1 Traffic and Transport Highway Link References
12.2 Traffic and Transport Construction Traffic Routes
12.3 Traffic and Transport Access Locations
12.4 Traffic and Transport Traffic Survey Locations
12.5 Traffic and Transport Public Rights of Way
12.6 Traffic and Transport Cycle Routes
12.7 Traffic and Transport Garth Visibility Splays
12.8 Traffic and Transport Cilfor Visibility Splays
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Background and Scope 1.7 The location and extent of the Proposed Project is presented in Figure 2.1 in Chapter 2 Project Description. The Proposed Project is to underground a 3.5km section of existing OHL (here on referred to as the VIP subsection) using a tunnel from a location close to National Grid’s existing Garth Sealing End Compound (SEC) on the western side of the Dwyryd Estuary to Cilfor on the eastern side of the Dwyryd Estuary and remove the existing VIP subsection (pylons and conductors). Construction compounds, laydown areas, and temporary access tracks will be required to facilitate construction activities.
1.8 The Proposed Project extent is presented in the Traffic and Transport Figures (12.1 to 12.8) and is comprised of key elements set out under the subheadings below. Existing and proposed pylon references are presented in Figure 2.1 and Figure 2.2 in Chapter 2 Project Description respectively. Full detail of the project components described below is provided in the Project Description Chapter 2.
Table 1-2: Location of Project Components Location Proposed Project Components
• Diversion of third-party assets, including the undergrounding of an OHL away from the construction area in accordance with operator requirements
• Reconfiguration of equipment at the existing Garth SEC (including removal of the gantry, there will therefore be no equipment greater than 10m high)
• A tunnel head house (containing a tunnel shaft), with a permanent Western Side of the access road close to National Grid’s existing Garth SEC. The ground Dwyryd Estuary will need to be raised out of the flood zone level. A permanent power supply will be required. (Planning Jurisdiction of • Underground buried cable to connect into the SEC from the tunnel Gwynedd Council) head house
• Removal of six pylons and associated foundation to 1.5m below ground level
• Temporary access routes (with potential highways improvements or passing places) and laydown areas to facilitate construction activities
• A section of cable tunnel (total length 3.3km long, with an internal diameter of up to 4.4m, at varying depths below the ground) Location Proposed Project Components
• Diversion of third-party assets including the diversion of a water pipeline away from the construction area in accordance with operator Eastern Side of the requirements Dwyryd Estuary • (Planning A new SEC near Cilfor (required to connect the new underground cable to the remaining existing OHL) Jurisdiction Snowdonia • A tunnel head house (containing a tunnel shaft), with a permanent National Park) access road. The ground will be raised to create a working platform and will be regarded/ contoured. A permanent power supply will be required.
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Snowdonia Visual Impact Provision (VIP) Snowdonia Project Project reference: Snowdonia VIP Project number: 60566917
Location Proposed Project Components
• A section of cable tunnel
• Removal and reinstallation of one pylon (Pylon 4ZC027) adjacent to the new Cilfor SEC
• Removal of two pylons and associated foundation to 1.5m below ground level
• Temporary access routes and laydown areas to facilitate construction activities Location Proposed Project Components
• A section of cable tunnel
• Removal of Pylon 4ZC030R, National Grid will also aim to remove all pylon structures including the foundation piles and cofferdam sheet piles; alternatively, foundations will be removed to the maximum depth Dwyryd Estuary possible by an excavator located on the working area (Planning Jurisdiction of • Partial removal of the foundations of the previously dismantled pylon Natural Resources 4ZC030 Wales) • Removal of Pylon 4ZC031 and partial removal of its foundations
• Temporary accesses associated with the removals noted above, as well as temporary access to enable the dismantling of Pylon 4ZC032 (although the pylon itself is within the terrestrial environment)
CTMP Objectives 1.9 This section outlines the objectives of this Outline CTMP and the purpose of the full CTMP to be developed by the contractor and maintained and updated throughout the construction phase of the Proposed Project. At the time of writing a contractor is yet to be appointed for the Proposed Project. Consequently, the Outline CTMP is intended to provide a framework for the appointed contactor to achieve the objectives contained within this document.
1.10 Once a contractor is appointed, it is intended that this document would form the basis of a comprehensive construction traffic management package which would be further developed and adhered to by the appointed contractor throughout the life of the Proposed Project.
1.11 This Outline CTMP establishes good practice principles to be implemented to mitigate, so far as reasonably practicable, the potential environmental effects of traffic during the construction phase of the Proposed Project. As a consequence, it is intended to consider the construction phase of the Proposed Project onl y; although reference is made to operation and maintenance activity and the decommissioning phase where relevant.
1.12 The key objectives for the Outline CTMP are shown in Table 1-3.
Table 1-3: Objectives of the Outline CTMP Objective Description
A Ensure that movements of people, plant and materials are achieved in a safe, efficient, timely and sustainable manner. B Ensure that any impact to the local communities and local tourism industry is reduced so far as reasonably practicable.
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Objective Description
C Ensure construction traffic levels are acceptable D Reduce and control construction vehicle trips where practical. E Ensure strategies and mitigation measures are implemented and adhered to through continued monitoring, review and improvement of the CTMP. F Limit the effects of construction traffic on the Local Road Network (LRN) and Strategic Road Network (SRN).
1.13 The measures included within this Outline CTMP are not intended to be exhaustive and the appointed contractor will be required to actively engage with National Grid and the relevant Highway Authority to ensure appropriate measures are implemented during the construction phase.
1.14 On this basis, and prior to the construction phase, the Contractor shall produce a detailed CTMP based on the outline plan which is to be implemented and monitored throughout the construction programme. The detailed CTMP shall ensure that all traffic associated with the project’s construction works operates in a safe and compliant manner at all times and shall be signed by the appointed Contractor and the relevant Highway Authority.
1.15 Building upon the objectives and information contained within this outline CTMP, the detailed CTMP development by the appointed contractor shall include working procedures and measures to:
─ Ensure the effects on residents, properties, businesses and schools caused by construction traffic, where practicable, are kept to an absolute minimum; ─ Maximise safety in all aspects of the project associated with the movement of traffic; ─ Ensure all third-party traffic interfacing with the project are kept safe from the on-going works; ─ Include clear liaison with the Local Authority regarding traffic caused by construction works; ─ Identify suitable signage and traffic controls to be used for all access points; and ─ Include a Driver Information Pack covering a variety of topics and providing information on the requirements of working on the project. Scoping and Consultation 1.16 The terrestrial element of the Proposed Project is located in the administrative boundaries of Gwynedd Council and Snowdonia National Park Authority. Activities within the Dwyryd estuary are within the planning jurisdiction of Natural Resource Wales.
1.17 In late 2017, consultation was undertaken with the Stakeholder Reference Group (SRG). At that time concerns were raised in relation to the potential volumes of additional traffic arising from an east-west direction of tunnel drive, and the potential impact upon Pont Briwet. As a consequence the west-east tunnel drive from Garth was explored, in the interest of minimising the impact of Proposed Project traffic along Pont Briwet.
1.18 Subsequently, consultation was undertaken with Gwynedd Council highways officers on the 8th August 2018 to discuss the construction traffic routing and access arrangements, the likely traffic effects arising from the Proposed Project and the requirement for traffic management and/or highways improvements across the LRN. Furthermore, public consultation events took place during late 2018. Members of the Traffic and Transport team attended an event in Penrhyndeudraeth in November 2018.
1.19 The scope and methodology of the Environmental Appraisal – including the provision of a CTMP to set out proposed mitigation measures – was submitted within the Screening and Scoping Report. A response to the Screening and Scoping Report was received in March 2019. Gwynedd Council Advised that:
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“The LPA understands that the Traffic Unit is satisfied with the proposal and welcomes the mitigation measures proposed. You are advised to discuss traffic management further with the Development Control Senior Engineer (sic)”
1.20 Matters scoped out of assessment for the Proposed Project are listed in the Environmental Appraisal (Environmental Appraisal Process Chapter 3).
1.21 It will be necessary to ensure that consultation and stakeholder engagement would continue to be conducted beyond this by National Grid and the contractor in order to inform the detailed CTMP and associated traffic management measures.
1.22 The mitigation measures outlined in Section 7 of this Outline CTMP include the appointment of a Traffic Safety and Control Officer (TSCO). A key aspect of their role would be to act as a point of contact for the Proposed Project throughout the construction phase and to liaise with local people, the local planning authorities, and any other relevant stakeholders.
1.23 Further information of scoping and consultation is provided within the Environmental Appraisal Traffic and Transport Chapter 12. Study Area 1.24 The ‘Study Area’ referred to henceforth in this Outline CTMP has been defined by identifying the links that construction traffic would be required to use in order to access the Proposed Project.
1.25 The most appropriate and likely routes for vehicles to access and egress the Proposed Project were identified considering their likely origins and destination points, the type of vehicles concerned, and the elements of the Proposed Project concerned. The Study Area assessed within this chapter is defined by a total of 15 highway links, comprising the Local and Strategic Highway Network. Section 3 of this Outline CTMP describes the routing strategy used to identify the prescribed highway links and associated Study Area.
1.26 In terms of highway links the Study Area commences from Porthmadog High Street and the A487 Porthmadog Bypass to the West and terminates on the eastern side of the Dwyryd Estuary, approximately 500m north and south of Cilfor, on the A496.
1.27 In addition to this, the Study Area was extended to encompass relevant BEIs and to consider non-motorised infrastructure relevant to the assessment - including the National Cycle Network and Public Rights of Way.
1.28 The Study Area for the assessment of Traffic and Transport impacts is presented on Figure 12.1 and Figure 12.2. Project Timescales 1.29 At the time of writing the Proposed Project is anticipated to commence construction in 2021 and is scheduled for completion approximately five years later, in 2026. These dates are subject to change and will be periodically updated within the contractors CTMP during the construction phase.
1.30 Peak construction activity is anticipated to occur during the tunnelling phase, associated with the transportation of aggregate and is expected to last 17 months.
1.31 Removal of the VIP subsection (‘OHL Removal) would take place following the completion of all tunnelling and associated works in mid-2026, lasting for approximately six months.
1.32 All construction work, including site dis-establishment is expected to be complete before the end of 2026.
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2. Construction Vehicle Classification
2.1 A wide variety of vehicle types would be used for the construction of the Proposed Project. Vehicles would be required to transport people, equipment and materials including aggregate that will arise from tunnel excavation. Volumes of Light Goods Vehicles (LGVs) and Heavy Goods Vehicle (HGVs) associated with the construction phase of the Proposed Project are detailed and assessed in the Environmental Appraisal Chapter 12.
2.2 For the purposes of the assessment, construction vehicles have been classified as follows, in accordance with the Driver and Vehicle Standards Agency Lorry types and weights guide 1:
─ LGV = Vehicles 3.5 tonnes (t) or below in gross weight; and ─ HGV = Vehicles above 3.5 t in gross weight. 2.3 Table 2-1 outlines the vehicle classification and typical vehicle types that would be required for the construction of the Proposed Project. These have been identified based on experience of those used for similar National Grid projects.
Table 2-1: Project Vehicle Classification
Vehicle Classification Example
LGV (i.e. 3.5 t or below) Car, van, 4x4 pick up, welfare van
HGV (i.e. over 3.5 t) Excavator, HIAB/winch tractor, tractor and trailer, 10 m and 12 m rigid vehicles, 20 t tippers, concrete mixers, 14 m and 16.5 m articulated vehicles, low loaders, small and large cranes (250 t and 300 t)
2.4 Further information on the volume of traffic of each type forecast to be generated by the Proposed Project is contained within the Environmental Appraisal (Traffic and Transport Chapter 12). However, peak traffic volumes are described below in order to provide an indication of traffic volumes of HGVs and LGVs during construction.
2.5 The peak construction activity in terms of traffic generation is expected to relate to the excavation of rock and soil during tunnelling. Tunnelling works are expected to take place for approximately 17 months. Current forecasts indicate that tunnelling will generate in the order of 30 loads per day, (60 two-way HGV movements) undertaken by vehicles with a load carrying capacity of 15m3. During this period, worst-case forecasts indicate that tunnelling activities could generate 160 two- way Light Goods Vehicles movements spread across three shifts.
2.6 In addition to LGVs and HGVs The Proposed Project would require the movement of Abnormal Indivisible Loads (AILs) which are defined as vehicles which fall outside the provisions contained within The Road Vehicles (Construction and Use) Regulations 1986 2 and The Road Vehicles (Authorised Weight) Regulations 1998 3.
2.7 AIL movements are considered and detailed in the AIL report included in Annex A of this document. As part of the detailed CTMP, the appointed contractor will be required to ensure that all AIL movements can be accommodated with the most up to date Proposed Project design following the planning stage.
1 https://www.gov.uk/government/publications/guide-to-lorry-types-and-weights 2 The Road Vehicles (Construction and Use) Regulations 1986. SI 1986:1078 (as amended) 3 The Road Vehicles (Authorised Weight) Regulations 1998. Si 1998:3111 (as amended)
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3. Construction Traffic Routes
3.1 The highway network within the Study Area is comprised of the Strategic Road Network (SRN) and the Local Road Network (LRN). Away from the public highway, the Proposed Project will also be served by temporary access tracks, which would provide access to working areas. Road Hierarchy 3.2 Welsh Government are responsible for managing the SRN within the Study Area and Gwynedd Council are responsible for managing the LRN.
3.3 In order to provide vehicular access and facilitate construction of the various elements of the Proposed Project there are three types of road network to be utilised (road hierarchy):
Table 3-1: Road Hierarchy Type Description
Type 1 – Strategic Road Network (SRN) Within the Study Area, this comprises the A487 running east-west from the commencement of the Porthmadog Bypass to the north east of Penrhyndeudraeth.
Type 2 – Local Road Network (LRN) Within the Study Area, this comprises the Gwynedd Council maintained LRN.
Type 3 – Temporary Access Tracks Within the Study Area, this comprises a network of temporary and existing access tracks which link the Proposed Project to the LRN.
Strategic Road Network 3.4 Construction traffic would be required to enter and leave the Study Area network via the SRN. The LRN will provide access between the SRN and construction traffic access points. HGV and LGV construction traffic routes are presented in Figure 12.2, Traffic and Transport Chapter 12. Local Road Network 3.5 Use of the LRN will be restricted for HGV traffic to a limited number of routes. Construction traffic routes have been identified in order to provide the most safe and suitable access for HGVs and LGVs along the LRN as far as reasonably practicable, with the intention of avoiding, for example, residential areas and sections of road sensitive to increases in traffic flows. Temporary Access Tracks 3.6 Temporary access tracks will provide access to work sites from the LRN. The construction of temporary access tracks would be informed by ground conditions in each location and therefore would be tailored accordingly.
3.7 For example, at the western tunnel head house it is expected that the presence of peat will necessitate the use of a ‘floating’ temporary access track design although this would be confirmed and designed in detail by the appointed contractor. In general, preference will be given to using plastic or aluminium road panels to construct temporary roads as opposed to stone aggregate.
3.8 In the case of the access to the eastern tunnel head house, the temporary access track would be upgraded to a permanent construction for the operational phase following the construction phase. This is discussed further in Section 4 of this Outline CTMP.
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3.9 Further information regarding the construction of temporary access tracks is provided in the Project Description Chapter 2. Routing Strategy 3.10 The routeing strategy is based on the following key principles:
─ Provide safe and efficient construction access for the Proposed Project; ─ Reduce, so far as reasonably practicable and mitigate to acceptable levels disruption to the public; ─ Avoid use of the A497 through Porthmadog by HGVs; ─ Prevent use of the northern section of the A496 by HGVs; ─ Where practical use the shortest route between the access point and the SRN; ─ So far as reasonably practicable avoid sensitive receptors ; and ─ HGV traffic will be required to enter the road network from the SRN (i.e. the A487). HGVs will then be required to follow prescribed routes to and from working areas. It should be noted that HGV routes would also be used by LGV construction traffic. 3.11 HGV and LGV construction traffic routes are shown in Figure 12.2 in Traffic and Transport Chapter 12 of the Environmental Appraisal. Table 3-2 sets out the links that form part of construction traffic routes and their associated ‘Link Reference’. These are presented in Figure 12.1, Traffic and Transport Chapter 12.
Table 3-2: Project Link References
Link Road Name Description LRN/ HGV/ LGV Ref. SRN
1 A487 Porthmadog Bypass SRN HGV 2 A497 Minffordd Roundabout to NCR8 LRN HGV 3 NCR8 Between A497 and Existing Garth SEC LRN HGV Compound 4 A497 Britannia Terrace LRN LGV 5 A487 Between Minffordd Roundabout and Pont SRN HGV Briwet
6 A487 Between Pont Briwet and Cambrian View SRN HGV 7 Pont Briwet Between Bron Meirion Surgery and A496 LRN HGV 8 A4085 North of A487/ School Street Junction LRN LGV 9 A487 East of Cambrian View SRN HGV 10 Cambrian View Between A487 and Pont Briwet LRN HGV 11a A496N North of Pont Briwet Junction to Access LRN HGV B9 11b A496N North of Access B9 LRN LGV 12 A496S South of Pont Briwet Junction LRN HGV* 13 A497 Porthmadog High Street LRN LGV 14 Unclassified Serving Maes Hendre, Adwyddu, and LRN LGV Road Maes Teg *Contingency Route: This link would only be used if all other possible construction traffic routes are unavailable for example due to an emergency event on the highway network.
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3.12 The contractor will ensure that HGV traffic will only use designated construction traffic routes during construction and provide details of how this will be enforced in the detailed CTMP. Notwithstanding that, the routes selected are generally the most direct, and therefore most likely to be used by HGV drivers which, it is anticipated, would minimise breaches of the prescribed routing and therefore the need for monitoring and enforcement. Highways Constraints and Considerations 3.13 Site visits and audits have taken place along the proposed construction traffic routes and at construction access points. Matters which have been considered to inform the construction traffic routing are as follows:
─ Height and weight restrictions; ─ Highway classification; ─ Highway st ructures; ─ Highway layout (width and horizontal/vertical alignments); ─ Traffic calming measures; ─ Built environment indicators (BEIs) adjacent to the highway; ─ Visibility constraints; ─ Speed limits and surveyed traffic speeds; ─ PRoW; and ─ Other road users (pedestrians, cyclists and equestrians). 3.14 In order to minimise the potential environmental effects of the Proposed Project, and in accordance with the objectives set out in Table 1-3, mitigation measures were embedded into the design of the Proposed Project (‘Embedded Mitigation’). A full list of Embedded Mitigation relating to traffic and transport is provided within the Environmental Appraisal, Traffic and Transport Chapter 12.
3.15 Table 3-3 details the existing highway constraints and considerations, how they have been mitigated at the construction traffic routing and access planning stage (‘Embedded Mitigation’) and further opportunities for mitigation during the construction stage.
3.16 Additional mitigation is proposed as a minimum, where the Environmental Appraisal has identified the need for intervention to mitigate environmental effects to an acceptable level. Notwithstanding that, the proposed potential mitigation during the construction phase of the Proposed Project highlighted in Table 3-3 and detailed in Section 7 of this report, includes additional best-practice measures to ensure effects across the Study Area arising from construction traffic are minimised so far as reasonably practicable.
3.17 All mitigation measures are discussed in more detail in Section 7 of this report.
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Table 3-3: Road Network Constraints and Considerations
Stage of Mitigation Constraint/Consideration Potential Mitigation Proposed construction traffic routes Construction Traffic Urban areas (villages, towns, avoid sensitive areas so far as Routing and Access schools) Planning Stage reasonably practicable.
Narrow local roads and Avoid unsuitable LRN where practical. junction constraints Suitable traffic management to be implemented at locations.
Construction Traffic Existing highway conditions Appropriate inspections and condition Routing and Access surveys to be agreed with Local Planning & Highways Authorities (Highway Construction Stage Authority).
Existing highway structures Structure locations identified and avoided where practical. Appropriate surveys to be undertaken (to be agreed with Highway Authority)
Visibility at access points Visibility based on Technical Advice Note (TAN) 18. Appropriate vegetation clearance, traffic management and speed reduction measures to be implemented to achieve safe access.
Impact on pedestrians and Construction traffic routeing strategy. cyclists Appropriate traffic management, signage and communications.
Road safety Construction traffic routes and temporary access design. Suitable traffic management, signage and communications. Road safety awareness amongst contractors and continued liaison with Highway Authority and emergency services.
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Contingency Routes 3.18 In order to ensure that construction activities are not unduly disrupted by unforeseen events on the road network (e.g. closures and diversions) it is considered necessary to consider alternative routes for HGV construction traffic. Consequently, the southern section of the A496 (Link Ref 12) has been identified as a ‘Contingency Route’.
3.19 Contingency routes would only be used if one of the preferred construction traffic routes became unavailable. A route is considered to be ‘unavailable’ if it is either closed (by the Highway Authority or the police) or becomes subject to a restriction making it unsuitable for construction traffic (for example a weight or height restriction). The HGV contingency route on the southern section of the A496 is shown alongside preferred construction traffic routes in Figure 12.2. Workforce Travel & Parking 3.20 It is anticipated that a peak workforce of up to 100 personnel could be present on site across the Proposed Project during the busiest periods, including all contractors and sub-contractors.
3.21 The tunnelling phase is forecast to result in peak workforce numbers. It is currently anticipated that these activities at the Garth construction compound would take place over three shifts during a 24-hour period.
3.22 A dedicated staff compound and car park will be provided at each tunnel head house during the construction phase which would accommodate approximately 40 spaces at Garth (West) and 20 spaces at Cilfor (East). As these sites would be required to accommodate shift handovers, there would not be sufficient space for each member of staff to travel to these working locations by car alone.
3.23 Nonetheless it is expected that much of the workforce would be residing locally and would therefore share car journeys to site. Whilst it is not expected to occur, obstructive and inconsiderate parking by contractors and staff on adjacent highways would impede construction activities and cause inconvenience to local communities; it would therefore be enforced against as part of the management of each working location.
3.24 In order to manage staff, travel patterns, minimise the impact upon the LRN, limit the demand for on-site parking, and to avoid on-street parking near work sites, the contractor will be required to implement measures to minimise single-occupancy car trips to worksites. This might include, for example, a permit scheme, lift-sharing register, and offering minibus pick-ups for staff staying locally.
3.25 National Grid are currently exploring the potential of using a mini bus to transport construction workers to the site at shift changes; this vehicle is likely to be over 3.5 tonne and therefore considered to be an HGV. Should this mode of transport for construction workers prove viable, National Grid would request that this vehicle is excluded from any restriction on HGV movement so that traffic movements to/ from the site can be reduced.
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4. Construction Traffic Access Access Locations 4.1 Vehicular access associated with the Proposed Project is comprised of up to 13 temporary and permanent access locations, including those which will be used to facilitate OHL removal. All access locations are presented on Figure 12.3 Traffic and Transport Chapter 12 and listed in Table 4-1.
4.2 Temporary Access Locations and Permanent Access Locations associated with the Proposed Project are defined as follows:
─ Temporary Access Locations - those to be used exclusively during the construction phase by Proposed Project construction traffic. ─ Permanent Access Locations - those to be retained and used for the operation and maintenance phase of the Proposed Project 4.3 Accesses have been located and designed in order to reflect the type, and frequency, of vehicular access required during the construction and operation and maintenance phases of the Proposed Project.
4.4 Some access locations make use of existing access points ; however, as part of the embedded mitigation, access to some work sites has been selected in some instances to avoid sensitive parts of the network and built environment indicators (e.g. settlements, schools) and to ensure that access is safe and fit for purpose.
4.5 Swept path analysis has been undertaken at each location for the largest anticipated vehicle type. The Proposed Project boundary therefore reflects the maximum extent it is expected that will be required in order to accommodate these vehicles. The contractor will be required to ensure that the design of each access is suitable to accommodate the type and frequency of vehicles associated with the construction element served by that access in consultation with National Grid and the Local Highways Authority.
4.6 Notwithstanding that, it is expected that traffic management measures could be implemented in many of the temporary access locations to minimise the need for the time and disruption associated with physical highway works. The approach to traffic management during the construction phase of the Proposed Project is discussed in detail in Section 5 of this Outline CTMP. Project Phasing: Temporary and Permanent Access 4.7 All project access locations are presented in Figure 12.3 and in Table 4-1. Access points referred to as ‘A’ relate to tunnel construction and operation whilst those referred to as ‘B’ relate to OHL removal. In addition to stating whether the access location is temporary or permanent, Table 4-1 indicates where an access location is new or would involve the use of an existing access location.
4.8 Each of these access locations would serve one or more elements of the Proposed Project listed in Section 1 of this Outline CTMP. The following sub-section lists the key project elements and the proposed accesses expected to serve each element. For the purposes of this section, the key elements of the Proposed Project are:
─ Tunnel head houses (Garth and Cilfor) ; ─ Sealing End Compounds (Existing and proposed permanent access, at Garth and Cilfor respectively); and ─ OHL removal (Removal of the existing VIP subsection).
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Snowdonia Visual Impact Provision (VIP) Snowdonia Project Project reference: Snowdonia VIP Project number: 60566917
Table 4-1: Construction Access Schedule
Ref Element Served Existing Description Status Start Date* A1a Garth construction compound No New Access as per Environmental Assessment Figure 12.7 Temporary (New) May 2021
A1b Garth tunnel head house No During construction this access is subject to requirement; as presented Permanent (New) May 2021 on Figure 12.7, land has been allocated for up to two accesses during the construction phase. In the event that this access is created for the construction phase, the access will be upgraded / repositioned to provide access and egress to the tunnel head house during the operational phase. In any case, A1b would be constructed to provide access during the operational phase as per Figure 12.7. A1c Garth SEC/ OHL Removal Yes Existing access to Garth SEC Permanent June 2025 (Existing)
A2 Cilfor tunnel head house/ SEC/ No New Access as per Figure 12.8. Upgraded access to be retained for Permanent (New) August 2021 OHL Removal/ Pylon Dismantling operational phase.
B1 OHL Removal/ Pylon Dismantling Yes Field Gate Temporary April 2026 (Existing)
B2 OHL Removal/ Pylon Dismantling Yes Via Minffordd Station Car Park Temporary April 2026 (Existing)
B3 OHL Removal/ Pylon Dismantling Yes Bellmouth on A487 approx. 50m east of Minffordd Roundabout Temporary April 2026 (Existing)
B4 OHL Removal/ Pylon Dismantling Yes Field Gate Temporary April 2026 (Existing)
B5 OHL Removal/ Pylon Dismantling Yes Field Gate from Pont Briwet (Opp. Cambrian View) Temporary April 2026 (Existing)
B6 OHL Removal/ Pylon Dismantling Yes Bellmouth access on Pont Briwet Temporary April 2026 (Existing)
B7 OHL Removal/ Pylon Dismantling Yes Existing Bellmouth Temporary April 2026 (Existing)
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Snowdonia Visual Impact Provision (VIP) Snowdonia Project Project reference: Snowdonia VIP Project number: 60566917
Ref Element Served Existing Description Status Start Date* B8 OHL Removal/ Pylon Dismantling Yes Existing access opposite Welsh Water compound Temporary April 2026 (Existing)
B9 OHL Removal/ Pylon Yes Field gate to A496N Temporary April 2026 Dismantling/ (Existing)
*Estimated start dates for use of the proposed access locations by construction traffic are approximates based on the most up to date construction programme and may be subject to change.
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Snowdonia Visual Impact Provision (VIP) Snowdonia Project Project reference: Snowdonia VIP Project number: 60566917
Access to Tunnel Head Houses 4.9 Tables 4-1 and Table 4-3 describe the temporary (construction phase) and permanent (operational) access arrangements for the tunnel head houses.
4.10 Subject to approval from the local Highway Authority, construction and operation access to the tunnel head houses is shown on Figures 12.7 and Figure 12.8 respectively. Access to Sealing End Compounds (SECs) 4.11 Table 4-1 and Table 4-3 describe the access arrangements for the SECs during construction and operation.
4.12 Subject to approval from the local Highway Authority, temporary and permanent access to the SECs is shown on the Figures 2.1 and Figure 2.2 respectively. OHL Removal 4.13 This section provides an overview of likely considerations relating to construction traffic with those works, access locations and working practices.
4.14 Accesses B1 to B9 (‘OHL access locations’) will be used for removal of the existing VIP subsection. It is anticipated that this would take place in 2026, following completion of the other elements of the Proposed Project.
4.15 These access points would provide direct construction traffic access to and from the LRN and SRN. As per Table 4-1, It is expected that all OHL access locations will make use of existing accesses. Notwithstanding that, physical improvements and/or traffic management will be implemented where necessary in order to help ensure their safe use by construction traffic.
4.16 As per Table 4-1, it is intended that these access locations would either be removed, permanently retained/ restored to their existing condition or retained with any physical improvements subject to agreement with the relevant Highway Authority and landowners. The locations of all access points are presented in Figure 12.3, Traffic and Transport Chapter 12.
4.17 It is anticipated that vehicles involved in pylon removal would typically include cars, vans, low loaders, cranes, 20t tippers and articulated HGVs. Conductor Removal 4.18 Removal of the existing infrastructure (the VIP subsection i.e. removal of the OHL from Pylon 4ZC027 to 4ZC037) will take place following the installation and commission of the new underground cables.
4.19 The process of conductor removal requires crossing over existing roads, railway lines, and PRoW. Various levels of protection would be required at all crossing locations.
4.20 It is understood at the time of writing that there could be a requirement for temporary road closures/ diversions on the LRN associated with the removal of conductors. Scaffolding 4.21 Where scaffolding adjacent to the carriageway is required for OHL works then a site-specific risk assessment and method statement would be undertaken to determine appropriate traffic management, signage, safety clearance and level of protection. Strategic Road Network Crossings 4.22 Discussions with Welsh Government will need to be undertaken to determine the most suitable traffic management to be implemented in order to facilitate this element of the Proposed Development. The responsibility for this lies with the contractor appointed to undertake OHL removal works.
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Local Road Network Crossings 4.23 Traffic management requirements on the LRN for scaffolding and netting will be determined by a site-specific risk assessment to be arranged by the contractor and agreed with the relevant Highway Authority prior to commencement of works. Traffic management such as temporary traffic signals, stop/go boards or traffic marshals could be used where appropriate to minimise disruption and delay on the LRN. Railway Line Crossings 4.24 The Proposed Development would require crossings of the Ffestiniog Railway Line and the Cambrian Line via access B2, B5, and B6. Appropriate applications, risk assessments and method statements would be undertaken in accordance with Network Rail’s requirements prior to commencement of works. Visibility Splays 4.25 Details of visibility splays at the Garth and Cilfor tunnel head houses for construction and operational access are presented in Figure 12.7 and Figure 12,8. In the interest of highway safety, the contractor will be required to ensure that visibility splays are managed and maintained in accordance with the approved plans.
4.26 In the event that there are locations where visibility standards cannot be met or where other environmental consideration are required to be taken into account (e.g. loss of habitat/ vegetation clearance), the contractor will be required to provide mitigation in agreement with the relevant Highway Authority.
4.27 OHL removal activities are not forecast to take place until 2026 and they are expected to be used for construction activities for a short, temporary period. Furthermore, many of these locations are currently used for inspection and maintenance activities associated with the existing VIP subsection. As a consequence, it is considered that it would be proportionate and appropriate to implement temporary traffic management measures to safely control construction traffic movements during this phase of the Proposed Project.
4.28 Notwithstanding that, as part of the ongoing liaison and consultation between National Grid, the appointed contractor and the Highways Authority it is considered that the opportunities to provide or maximise existing visibility could be agreed and, where deemed necessary, be implemented to the satisfaction of the Highways Authority. Temporary Access Tracks 4.29 Temporary access tracks will be provided as required between access points and working areas ; namely each tunnel head house, the new SEC at Cilfor, and to provide access during pylon and OHL removal. The appointed contractor will be responsible for ensuring the management and safe operation of vehicular movements along these access tracks.
4.30 Traffic management along temporary access tracks is discussed in more detail in Section 5. Operational Traffic Access 4.31 As mentioned earlier, activities during the operational and decommissioning phases are outside the scope of the CTMP. However, in order to demonstrate the significantly reduced volumes of traffic during operation and decommissioning and to demonstrate the suitability of permanent access points, typical maintenance activities associated with the Proposed Project elements have been extracted from the Environmental Appraisal Project Description Chapter 2 and presented in Table 4-2.
Table 4-2: Operation: Typical Maintenance and Inspection Activities
Project Element Typical Maintenance/ Inspection Activities Frequency • Head House Routine - above ground only; Headhouse/above Monthly includes site care, security and environmental ground structures routines. Inspection and basic maintenance
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Project Element Typical Maintenance/ Inspection Activities Frequency tasks (e.g. check operation, clean/replace filters, report defects). Walk of fenceline. Weekly(remotely) • Weekly remote check of system/alarms (action as necessary). • Civil inspection of shaft and tunnel lining, Below ground 3 Yearly base slab, cover slabs etc (outside lower infrastructure doors), crane or davit arm required. • ME and structure of, pressurised stairwell, 6 Monthly including sump pump (not outside lower (reviewed if doors) strategy amended) • Visual inspection of HV system and cleats, Underground high 6 Yearly SVL tests and replacement as necessary. voltage system Oversheath tests only where cable has semi- conductive oversheath. • Prep for monthly & Routine; check training Pre-inspection 6 Monthly and safety inspections up-to-date and all checks equipment available and within inspection dates. • Infrequent visits for replacement of pylon Terminal Pylons As required fittings/ anti climbing devices (ACDs), pylon steelwork / bracing. Vans would be used to carry workers in and
out of site and trucks would be used to bring new materials and equipment to site and remove old equipment (using permanent SEC Every 10-17 access road). years • Painting pylon steelwork.
4.32 As Table 4-2 demonstrates, maintenance and inspection activities associated with the Proposed Project are typically very infrequent and are associated with considerably less vehicular traffic than the construction phase.
4.33 Notwithstanding that, these activities do require the use of large vehicles and plant such as mobile cranes. Hence these accesses have been assessed for their ability to accommodate these vehicles. Furthermore, and as discussed earlier in this section, visibility splays would be provided at the permanent access locations at the tunnel head houses as per Figure 12.7 and Figure 12.8 (subject to agreement with the Highway Authority).
4.34 Furthermore, it is expected that the use of some of the mitigation measures set out in Section 7 of this Outline CTMP would be relevant the maintenance and inspection activities during the operational phase. Access Summary 4.35 Table 4-3 provides a summary of proposed access arrangement for each element of the Proposed project during construction and operation.
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Snowdonia Visual Impact Provision (VIP) Snowdonia Project Project reference: Snowdonia VIP Project number: 60566917
Table 4-3: Project Elements: Construction and Operation Access
Project Phase Location / Access Description Element Pylon Reference Tunnel Construction Garth A1a Temporary access at the Garth tunnel head house and construction compound would be provided by new head accesses onto Link Ref.3. house
Tunnel Construction Garth A1b As per Figure 2.1 and 12.7, up to two access may be required in order to serve the Garth compound. head Consequently, A1b represents a potential second access during construction. If implemented during house construction this access would be repositioned to act as permanent access to the tunnel head house during operation.
Tunnel Construction Cilfor A2 At Cilfor, access to the tunnel head house would be provided via a newly formed access (Access A2) to the head A496N (Link Ref 11). The access would operate as right-in/ left-out only for HGVs in accordance with the house designated construction traffic routes. Appropriate signage would be installed, along with Traffic Marshalls (as required) to ensure compliance and the safe movement of vehicles.
Tunnel Operation Garth A1b At Garth, the temporary construction access A1a would not be retained for the operation and maintenance head phases and would be removed and restored to the requirement of the local Highway Authority. Permanent house access to the tunnel head house would be provided via access A1b, located to the east.
Tunnel Operation Cilfor A2 Access to the east tunnel head house at Cilfor would be provided via upgrading of the temporary construction Head access and access track used during construction. House
SEC Construction Garth A1a/A1b Access to the SEC for reconfiguration works would be taken via the Garth compound access during the construction phase.
SEC Construction Cilfor A2 Access to the new SEC at Cilfor would be provided via access A2 as presented in Figure 12.8
SEC Operation Garth A1c During the operational phase, access to the reconfigured Garth SEC would revert back to the existing arrangement.
SEC Operation Cilfor A2 Access A2 would be retained permanently to provide access to the new Cilfor SEC along with the tunnel head house.
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Project Phase Location / Access Description Element Pylon Reference OHL Construction 4ZC037 A1c Access for OHL removal/ pylon dismantling via existing access to Garth SEC. Removal
OHL Construction 4ZC036 B1 Pylon access via existing field gate east of existing Garth SEC. Traffic management implemented as required Removal to facilitate HGV movements.
OHL Construction 4ZC035 B2 Pylon access via Minffordd Station Car Park. This would require crossing of the Ffestiniog and Welsh Highland Removal Railway. Traffic management implemented as required to facilitate vehicle movements.
OHL Construction 4ZC035 B3 Requires use of the bellmouth on A487 approx. 50m east of Minffordd Roundabout. Traffic management Removal implemented as required to facilitate HGV movements.
OHL Construction 4ZC034 & B4 Each pylon access via an existing access track adjoining Link Ref 14. Traffic management implemented as Removal 4ZC033 required to facilitate HGV movements at the junction with unclassified road and A487.
OHL Construction 4ZC032 & B5 Access from Pont Briwet. Traffic management implemented as required to facilitate HGV movements ; however, Removal 4ZC031 swept path analysis indicates that left turn in/ right turn out only would be feasible. Appropriate signage and traffic management measures required to minimise interaction with PRoW users. This access also requires crossing of the Cambrian Railway Line.
OHL Construction 4ZC030R B6 Bellmouth access on Pont Briwet. Traffic management implemented as required to facilitate HGV movements Removal (Dwyryd to ensure the safe crossing of the adjacent Cambrian Railway Line and minimise interaction with PRoW users. Estuary)
OHL Construction 4ZC029 B7 Pylon access via Existing bellmouth south east of Llandecwyn station. Traffic management implemented as Removal required to facilitate HGV movements.
OHL Construction 4ZC027R B8 Pylon accessed via the existing access opposite Welsh Water compound. Where possible, access A2 would Removal be used for access to avoid interaction with Talsarnau FP52. Notwithstanding that, if required, Traffic management implemented as to facilitate HGV movements at the access and minimise interaction with PRoW users.
OHL Construction 4ZC028 B9 Existing field gate north of Welsh Water site on A496N. Traffic management implemented as required to Removal facilitate HGV movements.
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Snowdonia Visual Impact Provision (VIP) Snowdonia Project Project reference: Snowdonia VIP Project number: 60566917
5. Traffic Management
5.1 There will be a requirement for traffic management and control methods in order to help meet the objectives of the CTMP. Traffic Signs Manual Chapter 8 states:
‘The complexity of traffic management arrangements varies from scheme to scheme but the primary objec tive is;
- to maximise the safety of the workforce and the travelling public.
The secondary objective is;
- to keep traffic flowing as freely as possible’ 4.
5.2 Where constraints on the highway network have been identified, and to reflect scoping discussions with the Local Highway Authority, traffic management has been identified as the preferred solution across the project rather than, for example, physical highway works or the removal of trees and hedges.
5.3 Traffic management on all routes would comply with the UK Government’s Code of Practice ‘Safety at Streetworks and Roadworks’ (DfT, 2013) 5 or other relevant legislation and guidance as appropriate at the time of implementation. The appointed contractor would agree traffic management and control methods with the relevant Highway authority prior to the commencement of any works.
5.4 Traffic management signage would be in accordance with the Traffic Signs Regulations and General Directions (TSRGD) 2016 and Traffic Signs Manual Chapter 8.
5.5 Traffic management associated with the Proposed project would comply with all requirements of the relevant Local Authority and the Police. The works would be organised so that the interference with vehicles and pedestrians using the highway and footpaths is kept to a minimum. Traffic management measures would provide, maintain and remove adequate protection in the form of barriers, hoardings, lights, etc. in accordance with the requirements of the local authority. Lighting and warning notices for vehicles and pedestrians would be provided as reasonably required by the local authority.
5.6 Contractor's vehicles and other vehicles would not be permitted to obstruct the highway by parking or waiting outside the site. Vehicles crossing footways to enter or leave the site would only be permitted to do so under supervision of a suitably trained Traffic Marshal. All vehicles over 3 tonnes (gross vehicle weight) on site which are required to reverse would be fitted with reversing cameras, visual and audible alarms. This would also be a requirement of all subcontractors' and suppliers' vehicles.
5.7 On-site speed limits would be implemented to minimise the risk associated with interaction between workers and site traffic.
5.8 All temporary traffic signs and road markings required would be installed prior to work taking place on site and non-illuminated signs would be reflective and maintained in a clean state throughout the period of works. Care would be taken to reposition, alter, or remove any signs and markings which become obsolete due to the appointed contractor's operations, and appropriate new signs and markings would be provided on reinstatement of working areas.
5.9 All vehicles would be required to be reverse parked. The site gates would be set back such that encroachment of traffic onto the public highway would not occur at any time.
4 Traffic Signs Manual Chapter 8 5 Department for Transport (2013) ‘Safety at Street Works and Road Works; Code of Practice’. Available from: https://www.gov.uk/government/publications/safety-at-street-works-and-road-works
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Snowdonia Visual Impact Provision (VIP) Snowdonia Project Project reference: Snowdonia VIP Project number: 60566917
5.10 The contractor would be required to keep private driveways free of contractor's equipment, vehicles and traffic and to ensure that any gates would not open outwards onto the highway and kept locked when not in use. Construction Traffic Routes and Access Signage 5.11 As part of the requirements of the detailed CTMP set out in Section 1 of this report, the Driver Information Pack would include a copy of the access route plans (Figure 12.2, Traffic and Transport Chapter 12) which would be provided to all suppliers and haulage operators by the contractor when orders are placed to ensure that drivers are fully briefed on the required routes to take. The supplier would be made aware that these routes are required to be followed at all times unless agreed or alternate diversions are in place, for example the use of the contingency route along the A496 S (Link Ref. 12).
5.12 Temporary signs providing route information for contractors would, with permission of the Highway Authority, be erected at key locations along the proposed construction traffic routes on the LRN and the SRN. Project information boards could be erected and, if required, would include important project information for the public and relevant contact details.
5.13 The design and location of route information signs and project information boards would be agreed with the relevant Highway Authority prior to installation. Signs would be bi-lingual, with messages written in Welsh above English on the sign face.
5.14 Consistent signage at access locations would be installed during use in order to provide relevant warnings and information to other road users of the presence of construction traffic. If required by the Highways Authority, these signs can be removed or covered when the temporary access is not in use. Temporary Access Track Signage 5.15 The contractor would be required to provide signage along off-road temporary access tracks to assist the appointed contractor to operate safely and efficiently. Signage on the temporary access tracks would include information such as: safety messages; advisory speed limits; typical and site-specific hazards; distance to the LRN; area of potential vehicle conflicts; a nd the presence of nearby Public Rights of Way (PRoWs).
5.16 Details of any signage required along these routes to alert site traffic and users of any nearby PRoWs would be agreed in consultation with relevant authority in advance of works at a given location. Location-Specific Traffic Management 5.17 Access locations have been identified where it may be necessary to introduce specific traffic management as additional mitigation. The locations have been identified based on the Environmental Appraisal (Traffic and Transport Chapter 12), on-site and desktop observations, and early discussions with the Highways Authority.
5.18 The locations, along with potential requirements for traffic management, are discussed further in this section.
5.19 The type of traffic management required at each location is dependent on a number of factors including traffic type, speeds and volume, road widths, visibility and site characteristics ; t raffic management could, for example, take the form of traffic control by marshal, priority signs, stop/go boards or portable traffic signals along with additional approach signage to reduce speeds where required.
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Garth Tunnel Head House And SEC 5.20 NCR8 (Link Ref 3) will operate as the route for the transportation of aggregate arising from tunnelling activities. Link Ref 3 adjoins the A497 east of Porthmadog and would provide access to the Garth construction compound (Via accesses A1a and A1b) during the construction phase and the tunnel head house during the operational phase (access A1c).
5.21 Consequently, the route is anticipated to see regular movements of HGVs, particularly during the tunnelling phase of construction work, which represents the peak traffic-generating period of the construction phase. It is expected that movements would predominantly be 20t tipper vehicles for transporting aggregate to and from site.
5.22 Desktop and on-site assessments, along with the Highway Safety assessment contained within the Environmental Appraisal have:
A) Indicated that the swept path of vehicles turning out of NCR8 (Link Ref. 3) onto the A497 (Link Ref. 2) crosses the centre line of the A497 ;
B) Indicated sections where the carriageway falls below 6.0m ; and
C) Highlighted the presence of a cluster of reported collisions on the A497 on approach to its junction with NCR8 Link Ref. 3).
5.23 It is therefore considered that mitigation will be required to minimise the impacts of the forecasts increases in volumes of HGV and LGV traffic associated with the tunnelling phase in particular.
5.24 The additional traffic may increase the risks associated with turning HGV traffic and mainline traffic on the A497 and, separately, between HGVs travelling in opposing directions along NCR Link Ref 3. It is therefore expected that mitigation measures will be required to minimise the risk of conflict between HGVs from the junction with the A497 and on sections along this route (NCR8, Link Ref 3).
5.25 As discussed earlier within this Outline CTMP, traffic management is the preferred project solution wherever reasonably practicable and it is considered that the use of traffic management would appropriately mitigate the identified risks.
5.26 Whilst the contractor would be responsible for developing, agreeing with the Highways Authority, and implementing the specific traffic management measures to mitigate this risk, measures might include the use of traffic marshals to communicate with site to ensure that vehicles are held on sections wide enough for two HGVs to pass safely (or on site) using temporary traffic signals for example, to allow priority working.
5.27 The appointed contractor would be responsible for identifying and implementing a method of mitigating any identified hazard in consultation with the relevant Highway Authority. In addition to traffic management arrangements, other mitigations measures, including physical highway improvements and HGV safety features would be implemented. Further detail of proposed mitigation measures along this route, and across the Proposed Project, is provided in Section 7. A487/ Pont Briwet/ Cambrian View 5.28 On-site observations have identified that the route from Pont Briwet (Link Ref 7) has a reduced carriageway width approximately 50m east of the Bron Meirion Surgery.
5.29 Whilst it is noted that HGVs currently use this route, a proposed alternative route could be considered using Cambrian View (Link Ref 10) to minimise the potential risk of conflict between HGVs along this section. It is proposed that this routing would apply for all HGVs travelling to work sites east of the Cambrian View/ Pont Briwet Junction. The proposed routing is presented in Inset 1.
5.30 In this arrangement it is proposed that all HGVs travelling eastbound on the A487 would turn right into Cambrian View, rather than Pont Briwet (Link Ref 7). These vehicles would then turn left from Cambrian View along Pont Briwet. Vehicles travelling westbound would then be required to join the SRN via Pont Briwet, at its junction with the A487 adjacent to Bron Meirion Surgery.
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5.31 The proposed routeing has been fully assessed within the Environmental Appraisal Traffic and Transport Chapter 12. On this basis the peak year increases in LGV and HGV traffic along this route are not forecast to result in any significant environmental effects.
Cambrian View
B5
Inset 1: Potential HGV Routing via Cambrian View 5.32 This proposed routing would not apply to traffic associated with OHL removal accessing Pylon 4ZC032 and 4ZC031.
5.33 Access to these pylons would require HGVs using access B5 to turn right out of the site ; swept path analysis indicates that a left turn out of the access would not be possible by some HGVs.
5.34 OHL removal activities associated with B5 would involve a modest volume of HGVs and would take place following tunnelling activities, which generates the peak volume of HGV during construction of the Proposed Project.
5.35 It is intended that traffic movements would be subject to monitoring by the contractor over the construction period and route amendments implemented as necessary by the contractor in consultation with the relevant Highway Authorities and/or through feedback from local stakeholders. Temporary Road Closures and Diversions 5.36 It is understood at the time of writing that there could be a requirement for temporary road closures or diversions associated with the Proposed Project during OHL removal, although this is subject to confirmation by the appointed contractor.
5.37 Should a temporary road closure and/or diversion be considered to be required, then the contractor must engage with the relevant Highway Authority to discuss their requirements and associated mitigation. Working Hours 5.38 Tunnelling activities will be a continuous operation seven days a week (24 hours a day). Tunnelling activities will involve above ground plant and equipment, tunnelling means testing of machinery, excavation and operation and maintenance of the TBM and excavation systems and plant.
5.39 National Grid request that work may take place between 0700 and 1900 Monday to Saturday and between 0900 and 1700 on Sunday (the core working hours), unless otherwise approved by the
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relevant planning authority. No excavated material shall be disposed off-site outside of these core hours.
5.40 National Grid also request that the following operations may take place outside the core working hours referred to above (exempt activities):
─ completion of operations commenced during the core working hours which cannot safely be stopped; ─ any highway works requested by the Highway Authority or requested by third parties such as network rail ; ─ security monitoring; ─ the completion of works delayed or held up by severe weather conditions which disrupted or interrupted normal construction activities ; and, ─ cable jointing and installation and associated works inside the completed shaft and tunnel. 5.41 The core working hours referred to above include start up and close down activities up to one hour either side of the core working hours. In all instances there will be no movement of excavated material offsite during weekends and no deliveries outside of the core working hours unless deliveries are specifically required to carry out those exempt activities listed above, which may take place outside of the proposed core working hours.
5.42 For appraisal purposes it has been estimated that three shift changeovers will be required during tunnelling activities with less people working on-site over the evening / night-time shift patterns.
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Snowdonia Visual Impact Provision (VIP) Snowdonia Project Project reference: Snowdonia VIP Project number: 60566917
6. Non-Motorised Users Public Rights of Way 6.1 Figure 12.5 presents the Public Rights of Way (PRoW) within the Study Area. PRoW expected to directly interact with construction activities are summarised in Table 6-1.
Table 6-1: PRoW Interaction with Proposed Project
PRoW Project Element Description Penrhyndeudraeth OHL Removal, Access to pylons for dismantling and OHL Restricted Byway 26 Trackway removal on the Dwyryd Estuary (Pylon Installation, Access 4ZC032, 4ZC031 and 4ZC030) requires the Track Upgrade use of Penrhyndeudraeth Restricted Byway Penrhyndeudraeth OHL Removal, 26 and Penrhyndeudraeth Footpath 26, Footpath 26 Trackway including the installation of trackways and Installation, Access upgrading of Access Tracks. Track Upgrade Penrhyndeudraeth OHL Removal, Penrhyndeudraeth Footpath 24 crosses the Footpath 24 Pylon Foundation proposed working area for OHL removal Removal, Access between Pylon 4ZC032 and 4ZC033. Track Upgrade Talsarnau Footpath 52 OHL Removal, Talsarnau Footpath 52 is located adjacent Pylon Foundation to Pylon 4ZC027. The proposed working Removal, Access areas for dismantling of 4ZC027 and Track Upgrade, installation of the replacement terminal Puller/ Tensioner pylon 4ZC027R are expected to interact Platform with this PRoW
6.2 It is anticipated that a temporary closure of each PRoW may be required in order to facilitate resurfacing and widening of the access tracks, installation of temporary trackway to provide access to these Pylons, and during OHL and foundation removal (Figure 2.1). Notwithstanding that, it is expected that there may be opportunities to adopt alternative approaches to minimise the duration of closures.
6.3 Where possible and safe to do so, to minimise disruption to PRoW users, effort will be made to limit the duration of temporary closures. In these instances, alternative approaches such as diversion routes and management of the PRoW will be discussed and agreed in consultation with Gwynedd Council PRoW officers.
6.4 Where activities affecting PRoWs are of a sufficiently short duration or where temporary access tracks follow an existing PRoW, management might include the use of contractor staff to hold PRoW users for short periods (a few minutes) while construction vehicles pass or while construction activities are undertaken.
6.5 All locations where a PRoW would be impacted by the Proposed Development would have appropriate signage, which would advise of dates and hours affected together with signs warning drivers of construction vehicles using the temporary access track of the likely presence of PRoW users crossing the temporary access track. The location of signs providing information on tempo rary diversions and closures would be discussed with the PRoW Officer. Where applicable; maps showing temporary diversions and alternative PRoW would be provided at the site. Signage erected would be bilingual in Welsh and English.
6.6 Aside from these locations the Proposed Project, and associated construction traffic is not expected to interact with any other PRoW. No permanent closures or diversions are proposed as a consequence of the Proposed Project.
Prepared for: National Grid Electricity Transmission Plc AECOM 31
Snowdonia Visual Impact Provision (VIP) Snowdonia Project Project reference: Snowdonia VIP Project number: 60566917
Wales Coast Path & Other Recreational Routes 6.7 Sections of the Wales Coast Path (WCP) are located within the Study Area, namely along Pont Briwet (Link Ref 7) and the A487 (Link Refs 5,6, and 9)
6.8 Despite the proximity to the Proposed Project, it is not expected that construction traffic will directly interact with users of the WCP during construction. Where access points are located along links shared with the WCP, route information signs, project information boards and any Chapter 8 signage associated with traffic management would be in place to alert pedestrians to the presence of HGVs. Additionally, traffic marshals could be used in such location to hold site traffic as required.
6.9 It is also noted that a number of other recreational long-distance walking routes are located within the Study Area, including Snowdonia Way, Taith Ardudwy Way, O Fon I Fynwy, Mawddach- Ardudwy Trail, and Meirionydd Coast Walk.
6.10 Where these routes are located along existing PRoW closures would be required as described above or, where possible, managed to minimise disruption and inconvenience to tourists and the local community. Local walking groups and other relevant stakeholders would be informed of any planned closures or diversion and signage would be located along the routes in advance of any nearby works, closures, or diversions to ensure that any changes are communicated well in advance. Cycle Routes 6.11 National Cycle Route 8 (NCR8) and NCR82 are located within the Study Area. In parts, they are located along designated construction traffic routes.
6.12 The extent of NCR8 and NCR82 within the Study Area are presented in Figure 12.6 Traffic and Transport Chapter 12. NCR8 6.13 NCR8 is located along a number of the links within the Study Area. The route is comprised of sections of shared routes and sections where cyclists and vehicular traffic are segregated.
6.14 NCR8 is located along a number of links within the Study Area. The route is comprised of sections of shared routes and section where cyclists and vehicular traffic are segregated. Figure 12.6 distinguishes between segregated and unsegregated section of each of the cycle routes within the Study Area.
6.15 Link Ref. 3 - the route to the Garth tunnel head house - is used by both cyclists and walkers. Cyclists and walkers are not segregated on this route and share the carriageway with vehicular traffic. This link is proposed to be used as an HGV route, particularly during the peak year tunnelling phase of the construction programme where it would be trafficked by HGVs transporting spoil away from the drive site. Baseline levels of HGVs are currently very low, and the Proposed Project would therefore result in a notable increase in HGVs during the tunnelling phase of the Proposed Project.
6.16 Classified Automatic Traffic Counts were undertaken over two-week periods in August 2016, in order to capture the peak local tourist period. These provided data on the number of cyclists using this route. A summary is presented in Table 6-2.
Table 6-2: ATC Cyclist Data - NCR8 (Link Ref 3)
Date Weekday 7-Day Average Daily Maximum Hourly Maximum Average (Cycles) (Cycles) (Cycles) (Cycles) August 31 30 41 5 2016
Prepared for: National Grid Electricity Transmission Plc AECOM 32
Snowdonia Visual Impact Provision (VIP) Snowdonia Project Project reference: Snowdonia VIP Project number: 60566917
6.17 It is considered that Proposed Development traffic, particularly HGVs, can be managed alongside the existing volumes of cyclists.
6.18 NCR82 is located along the northern section of the A4085 (Link Ref. 8), adjoining NCR8 via an unclassified road to the west of the A4085. The A4085 (Link Ref. 8) is designated as an LGV route. Cyclists are not segregated from vehicular traffic on this route.
6.19 The presence of cycle routes, and quality of cycle infrastructure on them, has been used to inform the identified link values in Traffic and Transport Chapter 12.
6.20 HGVs used for the construction of the Proposed Project would be to the required Euro Class and could have additional cycle friendly measures such as cameras, sideguards, full length door windows, blind spot warning systems and additional mirrors (Class V and Vi). NCR82 6.21 This route is located along the northern section of the A4085 (Link Ref 8) within the Study Area. This route is designated as an LGV route and is expected to cater for minimal increases in traffic as a consequence of the Proposed Project. No specific measures are therefore proposed on this route. Mitigation for Non-Motorised Users 6.22 The appointed contractor will be required to implement appropriate mitigation measures along NCR8 (Link Ref. 3) to help ensure safety of cyclists is not compromised. Section 7 outlines measures that may be implemented to minimise the potential effects of Proposed Project construction traffic on cyclists on these routes.
6.23 Mitigation relating specifically to cycling would (in agreement with Gwynedd Council) include but not be limited to:
─ Signage alerting cyclists/walkers to the present of HGVs along the route to the tunnel head house; ─ Widening of the carriageway along NCR8 to provide passing places ; ─ Use of traffic marshals and radio-communication between the NCR8/ A497 junction and tunnel head house access to hold on site traffic where cyclists are using the route; and ─ If required, the introduction of a temporary speed limit reduction along the route. 6.24 Further information on the assessment of this route is provided within the Environmental Appraisal (Traffic and Transport Chapter 12). A full list of potential and proposed measures is provided within Tables 7-1 and 7-2 respectively.
Prepared for: National Grid Electricity Transmission Plc AECOM 33
Snowdonia Visual Impact Provision (VIP) Snowdonia Project Project reference: Snowdonia VIP Project number: 60566917
7. Mitigation Measures Proposed Mitigation Measures 7.1 This section sets out the mitigation measures identified for the Proposed Project that the contractor will be required to implement in agreement with the Highway Authorities and relevant stakeholders. Table 7-1 sets out the mitigation measures which would be required as part of the contractor’s responsibility under the CTMP. These are aligned to the objectives of the CTMP as set out in Table 1-3.
7.2 As described earlier in this Outline CTMP, mitigation is either defined as ‘Embedded’ (i.e. incorporated into the design of the Proposed Project) or ‘Proposed’ (i.e. measures that will be implemented and measures that could be implemented to mitigate the impact of additional construction traffic).
Table 7-1: Mitigation Measures
Mitigation Measure Ref. Outline CTMP Objective Prescribed HGV Construction Traffic Routes 1 A/B Only prescribed construction traffic routes are to be used for the construction of the Proposed Project. Appropriate self-enforcement and monitoring measures to reduce the need for the Highway Authority and NWP to enforce and monitor would be included within the conditions of contract and penalties would apply for non-compliance. Physical Highway Improvements 2 F Physical highway improvements to be implemented where considered necessary at access locations including, for example, amendments to existing accesses to accommodate the swept path of construction vehicles and road widening to facilitate two-way HGV flows. Road Safety Information 3 A/B National Grid, in consultation with the Highway Authority, would promote and publicise appropriate road safety information during the construction of the Proposed Project Community Engagement and Public Information 4 B/D Information regarding construction traffic activities and movements would be provided to the public. The means of communication could include online updates, letter drops, information boards and details of key contacts.
Traffic Management and Diversion Routes 5 A/B/F Where required, suitable traffic management would be implemented to ensure safe operation and to reduce as far as reasonably practicable the impact of construction vehicles on the highway network. If and where road closures are required, diversions would be put in place with suitable signage and monitoring. Temporary Traffic Regulation Orders 6 A/B/F Temporary Traffic Regulation Orders may be proposed to allow enforcement of reduced speed limits, road closures and parking restrictions.
Vegetation Management 7 A/B/F
Prepared for: National Grid Electricity Transmission Plc AECOM 34
Snowdonia Visual Impact Provision (VIP) Snowdonia Project Project reference: Snowdonia VIP Project number: 60566917
Mitigation Measure Ref. Outline CTMP Objective Where deemed hazardous, overgrown vegetation and grass verge encroachment onto the edge of carriageway along key construction traffic routes would be managed during construction traffic route use in consultation with the Project Ecological Clerk of Works. Wheel Cleaning Facilities 8 F Appropriate facilities would be installed at access locations to allow removal of debris from construction vehicles before they are allowed to egress. Street Cleaning Schedule 9 F The use of road sweepers throughout the construction of the Proposed Project would be agreed with the relevant Highway Authority. Delivery Management System 10 ALL Delivery records would be kept at the construction compounds at Garth and Cilfor. Delivery records would allow vehicular activities to be recorded, monitored and managed throughout the construction of the Proposed Project to ensure compliance with the Outline CTMP. HGV Traffic Movement and Timing Restrictions 11 C/D/F These may be necessary following the completion of the Environmental Appraisal in order to mitigate potential traffic effects and could include: • Timing restrictions, for example on routes close to schools during school drop off and pick up times; • Restrictions on the number of HGV movements in addition to those required at weekends (Paragraph 5.41), for example the AM or PM peak hour • Restriction of certain movements at certain locations to accommodate local special events. Details in terms of when and where restrictions may be required would be determined as necessary and monitored during the construction of the Proposed Project. HGV Emissions and Safety Features 12 A/B Typical HGVs used for the construction of the Proposed Project would be to the required Euro Class and could have additional cycle friendly measures such as cameras, sideguards, full length door windows, blind spot warning systems and additional mirrors (Class V and Vi). Abnormal Indivisible Loads (AILs) 13 A/B/E/F Temporary traffic management would be provided during AIL delivery where required, along with appropriate communications with the local community. Department for Transport ESDAL system would be used for notifications. Night deliveries would be undertaken where required, to reduce disruption and maintain safety on the LRN. Traffic Marshals 14 A If necessary, suitably qualified personnel would be present at key locations and times during construction to guide traffic and to enhance safety. Highway Condition Surveys, Maintenance and Repair 15 F
Prepared for: National Grid Electricity Transmission Plc AECOM 35
Snowdonia Visual Impact Provision (VIP) Snowdonia Project Project reference: Snowdonia VIP Project number: 60566917
Mitigation Measure Ref. Outline CTMP Objective A highway inspection, monitoring and repair strategy, to be deployed during the construction of the Proposed Project, would be agreed in advance with the relevant Highway Authority.
Traffic Safety and Control Officer (TSCO) 16 A/B/F The contractor(s) would appoint a TSCO for the duration of the construction of the Proposed Project. This might be carried out, for example, by the Environmental Manager or the Safety Officer for the Proposed Project. Their details would be provided to the Highway Authority prior to the commencement of the project. They would be responsible for updating the CTMP and would act as the main point of contact with the Highway Authority and emergency services and undertake the following duties: • Check and approve all traffic management drawings prior to issue. • Ensure sufficient resource available to maintain traffic management on site. • Monitor traffic management to ensure effectiveness and safety to workers and public. • Communicate with Highway Authority officers and emergency services, potentially via the TLG. • Provide a visible presence at site. Staff Travel Planning 17 C/D/F
National Grid would require the appointed contractor to introduce measures to reduce the volume of traffic travelling to work site. These measures might include the use of minibuses to collect workers from local accommodation, a lift sharing scheme, and reduced/ controlled parking at work sites.
7.3 Table 7-1 contains both embedded mitigation (i.e. mitigation by design) and all other mitigation measures that are proposed or would be proposed during construction in consultation with the highways authorities and other stakeholders. In some locations, the environmental appraisal has identified a need for location specific measures. These are detailed in the subsequent sub- section.
Prepared for: National Grid Electricity Transmission Plc AECOM 36
Snowdonia Visual Impact Provision (VIP) Snowdonia Project Project reference: Snowdonia VIP Project number: 60566917
Location Specific Mitigation Measures 7.4 The assessment contained within the Environmental Appraisal (Traffic and Transport Chapter 12) identified a need for mitigation measures at a number of locations within the Study Area.
7.5 Table 7-2 presents the location-specific mitigation proposed during the construction phase of the Proposed Project, to reduce impacts and potential environmental effects arising as a result of the forecast increases in traffic volumes.
Table 7-2: Proposed Mitigation During Construction Link Location Location Specific Mitigation Proposed Reference Ref
2 A497 Traffic management to be agreed with Highways Authority 5,2,6 on the approach to the A497/NCR8 junction. This would include, if required, a temporary speed limit reduction, introduction of high-friction surfacing, and advanced warning signage.
3 NCR8 Carriageway widening along route to tunnel head house 2,5,6,7,12,14 access to provide passing places/ total carriageway width of 6.0m minimum (Figure 2.1).
Traffic management along route to include a temporary speed limit reduction, and advanced warning signage.
The use of traffic marshals located at tunnel head house access and A497/ NCR8 to communicate presence of walkers and cyclists or to hold release of HGVs from site compound.
Typical HGVs used for the construction of the Proposed Project would be to the required Euro Class and could have additional cycle friendly measures such as cameras, sideguards, full length door windows, blind spot warning systems and additional mirrors (Class V and Vi).
11a A496N Traffic management along route to include advanced 5,6 warning signage and temporary speed reduction to 30mph from Pont Briwet /A496 junction to site access.
Where long distance walking routes (LDWRs) and cyclists cross the link, additional signage would be located to alert drivers to the presence of crossing pedestrians and cyclists.
7.6 It should be noted that in addition to those measures listed above the contractor(s), in agreement with the Highway Authority and National Grid, may identify a need to implement additional measures. Section 8 sets out how the CTMP is expected to be implemented during the construction phase.
Prepared for: National Grid Electricity Transmission Plc AECOM 37
Snowdonia Visual Impact Provision (VIP) Snowdonia Project Project reference: Snowdonia VIP Project number: 60566917
8. Monitoring and Review Communication 8.1 As a ‘live’ document, the management and mitigation measures included in the Outline CTMP would be developed during the construction programme within the detailed CTMP.
8.2 The Traffic Safety and Control Officer (TSCO), would be expected to continually engage with key stakeholders and the community as necessary and relevant. This could include a regular dial-in between stakeholders including the emergency services, North Wales Police and Highway Authority, for example.
8.3 It would be the role of the TCSO to act as an intermediary between National Grid, the contractor and key stakeholders to maintain open and regular channels of communication so that any effects on the transportation network associated with the Proposed Project may be addressed as soon as reasonably practicable.
8.4 Through effective and regular communication between National Grid, the appointed contractor(s), and stakeholders, the TCSO will:
─ Communicate and monitor the CTMP and its mitigation measures; ─ Ensure records of HGV movements are maintained and reported; ─ Act as the first point of contact for the public, st akeholders and contractors; ─ Hold regular update meetings with Highway Authority and relevant stakeholders; ─ Record near misses, incidents and hazards and resolve issues as informed by contractors, stakeholders and the public; and ─ Monitor, review and improve, where necessary, the CTMP and associated mitigation measures. Compliance, Enforcement, and Corrective Measures 8.5 The detailed CTMP, developed on appointment of the principal contractor and following the planning process, would include specific measures describing how the contractor will ensure adherence to the mitigation measures proposed.
8.6 This would include details around the following:
─ The Traffic Safety and Control Officer’s role and responsibilities ; ─ The Delivery Management Sy stem; ─ HGV identification and tracking technology ; and ─ A highway inspection, monitoring and repair strategy, to be deployed during the construction of the Proposed Project. 8.7 Continued stakeholder engagement by National Grid and the appointed contractor(s) would help to ensure that any issues are recorded, addressed and that appropriate corrective measures are implemented in accordance with the CTMP objectives.
Prepared for: National Grid Electricity Transmission Plc AECOM 38
Snowdonia Visual Impact Provision (VIP) Snowdonia Project Project reference: Snowdonia VIP Project number: 60566917
Annex A: AIL Report
Prepared for: National Grid Electricity Transmission Plc AECOM 39
Nunn, Clive
Subject: FW: A487 Bontnewydd Bridge
From: Daisy Gosling [mailto:[email protected]] Sent: 02 April 2019 10:34 To: Nunn, Clive
Good morning Clive,
Hope you are well.
Following Andy’s email of 31.08.18, please see below email from North Mid Wales Trunk Road Agency ref Glaslyn and Snowdonia loads (highlighted in yellow).
This latest update we have been chasing for some time, regarding the problem structure on the A487, and now means that your loads can access your sites in North Wales.
If you require any further clarification, please do not hesitate to contact us.
Best regards, Daisy
From: Jackson Martin (CEFNFFYRDD)
Daisy
The loadings from the vehicles given with your e-mail below have been checked and the results are as given below:
Assessments of the four proposed vehicles have been undertaken as requested and all can pass, although some need to have additional control measures to movement.:
Snowdonia Cutting Head - Dwg No 18-954.TC01 Vehicle can pass over bridge Glaslyn Cable Drum – Dwg No 18-953.TC01 Vehicle can pass over bridge 115te Transformer 3.0m Width – Dwg No FH-Ffest18-TC01 Vehicle can only pass at speeds less than 10mph and should follow East kerbline (Southbound Carriageway). 115te Transformer 2.7m Width – Dwg No FH-Ffest18-TC02 Vehicle can only pass at speeds less than 10mph and should follow East kerbline (Southbound Carriageway).
1 At present Bont Newydd has had intrusive investigations which have confirmed the presence of grouted backing to the bridge arch which can be accepted to extend up to 1.5m above the arch springing. The analysis and results above have been carried out based on this level of backing.
Due to high water levels in the river the current investigations had to be limited. However there is an intention to undertake further investigations to determine if the backing actually extends higher than the known location of 1.5m above the arch springing. It there is backing higher than current investigations this will provide further improvements to the structure capacity.
It should be noted that should additional depth of structural backing be found, the two 115te Transformer vehicles will be able to pass over the bridge without additional control measurers; it would therefore be worth checking vehicles again in the future if this influences your study.
If any further information or clarification is required do let me know. I trust this information meets your needs.
Regards
Martin Jackson Prif Reolwr Strwythurau / Principal Structures Manager Asiant Cefnffyrdd Gogledd a Chanolbarth Cymru North & Mid Wales Trunk Road Agent Automobile Palace, Temple Street, Llandrindod Wells, Powys, LD1 5HU ' 01597 829581 ' 07789 654014 * [email protected] Yn gweithio ar ran Llywodraeth Cymru Working on behalf of the Welsh Government
Bydd y ddwy iaith yn cael eu trin yn gyfartal o dan bob amgylchiadau / Both languages will be treated equally in all circumstances.
From: Daisy Gosling
Hi Martin,
Thanks for getting back to me so quickly.
Apologies for that – our mistake!
Please see attached 42te tractor unit that matches the axle loads in the load table of our drawing. Please note that tractor and draw bars are interchangeable, and these are indicative dimensions only. 2 Hope that clarifies.
Best regards, Daisy
From: Jackson Martin (CEFNFFYRDD)
Daisy
I thank you for your e-mail below dated 19th February. I can confirm that Gwynedd should have time to look at the loadings of the various AILs potentially crossing A487 Bontnewydd Bridge in the next week.
However they have looked through the load information provided and they think it may be missing the appropriate axle spacing for the 115te transformer loads. I hope you can assist with resolving a couple of queries. In the attached they have circled the axles and loads of the tractor unit, there appears to be three indicated in the elevation and four in the table. Can you confirm this information please? Can the number of wheels and spacings on the tractor unit axles also be confirmed please?
Regards
Martin Jackson Prif Reolwr Strwythurau / Principal Structures Manager Asiant Cefnffyrdd Gogledd a Chanolbarth Cymru North & Mid Wales Trunk Road Agent Automobile Palace, Temple Street, Llandrindod Wells, Powys, LD1 5HU ' 01597 829581 ' 07789 654014 * [email protected] Yn gweithio ar ran Llywodraeth Cymru Working on behalf of the Welsh Government
Bydd y ddwy iaith yn cael eu trin yn gyfartal o dan bob amgylchiadau / Both languages will be treated equally in all circumstances.
From: Daisy Gosling
Hi Nic,
3 Thanks for getting back to me.
Oh, some good news!
Please see the attached loads that I provided to Steven on the original email of this thread.
Let me know if you require any additional information.
Best regards, Daisy
From: Wright Nic (CEFNFFYRDD)
Daisy,
The recent concerns over the bridge due to the initial assessment for AIL loading have been alleviated following further examination and re-assessment.
If you can provide details of exceptional loads now would be a good time to check them.
Regards,
Nic Nic Wright Prif Reolwr Strwythurau ( Gogledd ) ~ Principal Structures Manager ( North ) Asiant Cefnffyrdd Gogledd a Chanolbarth Cymru ~ North & Mid Wales Trunk Road Agent NMWTRA, Fullbrooke Buildings, Halkyn, Holywell, Flintshire, CH8 8BY ( Halkyn 01352 782120 / Mob 07971 674126 * [email protected]
Yn gweithio ar ran Llywodraeth Cymru Working on behalf of the Welsh Government
From: Daisy Gosling
Good afternoon Nic,
Hope you are well.
I’ve just tried to chase an update from Steven regarding the below, however I have been told he is on leave for a week from today.
4 Is this something you could provide an update on in his absence?
Best regards, Daisy
From: King Steven Gruffudd (CEFNFFYRDD)
Hi Daisy,
Thank you for your email. This is just a holding response whilst I consult with structures. I will be back in touch with a response.
Kind regards Steve
Steven Gruffudd King LLB PGDip Swyddog Meddiannaeth y Rhwydwaith a Llwythau Annormal / Network Occupancy and Abnormal Loads Officer Asiant Cefnffyrdd Gogledd a Chanolbarth Cymru North & Mid Wales Trunk Road Agent Neuadd y Sir, Aberaeron SA46 0AT ( 01545 571960 * [email protected]
From: Daisy Gosling
Good afternoon Steven,
Hope you are well.
Following the ongoing discussions regarding Bontnewydd Bridge, south of Caernarfon, we are still seeking confirmation of the structure’s suitability for various loads required in North Wales.
Please find attached proposed loadings for your consideration, detailing the following;
Glaslyn & Snowdonia Projects · Drawing Number 18-953.TC01 (43.35te Cable Drum) - 4 axle goose neck low bed trailer at 81.35te gross weight
5 · Drawing Number 18-954.TC01 (50te Tunnel Boring Machine Cutterhead) - 4 axle steerable step frame trailer at 79te gross weight (5m wide)
Ffestiniog Power Station (115te Transformer) • 10 axle flat top trailer at 147.5te gross at 3m width • 10 axle flat top trailer at 146te gross at 2.7m width
If you could please get back to me with an update regarding Bontnewydd Bridge only in this instance, we would be most grateful.
Trust this makes sense.
Please let me know if you require any further information or clarification.
Best regards, Daisy
(Email Signature yet to be updated)
6
Abnormal Indivisible Load Access Study - Transportation of Tunnel Boring Machines to proposed locations for Snowdonia Visual Impact Provision
Prepared for WSP
WSP I 18-954 Snowdonia VIP I TBM I AIL Access Report I 10.09.18
Daisy Wynn 06.09.18
Peter Wynn 07.09.18
Andy Pearce 10.09.18
10.09.18 Final Report
WSP I 18-954 Snowdonia VIP I TBM I AIL Access Report I 10.09.18 Issue 0 I Contents & Executive Summary I Page i of xxx
Contents
Executive Summary iii
1. Introduction 4 2. Historical Information 4 2.1. Movement Along Welsh Routes (MAWR) 4 2.2. Porthmadog and Trawsfynydd Power Station & Substation 5 2.3. Ffestiniog Power Station 5 2.4. Pentir Substation 6 2.5. Maentwrog Power Station 6 3. Highways England Agreement in Principle and Legislative Requirements 7 3.1. Definition of Abnormal Indivisible Load (AIL) 7 3.2. Legislation 7 4. Abnormal Indivisible Load Movements - Highways Act 1980 8 4.1. Recovery of Excessive Maintenance Costs - Section 59 Agreements 8 4.2. The Removal and Replacement of Street Furniture 8 5. Plant Dimensions Included within Study Work 9 6. Transport Configurations 9 6.1. Tunnel Boring Machines 9 7. Structural Route Information 10 7.1. Tunnel Boring Machine Access 10 8. Route Negotiability 13 8.1. Route to TBM West Site 13 8.2. Route to TBM East Site 21 9. Summary and Conclusions 25
Appendix 1 27 Maps 27 Appendix 2 28 Drawings & Transport Configurations 28 Appendix 3 29 Highways England Aid Memoir 29 Appendix 4 30 Selected Correspondence 30
WSP I 18-954 Snowdonia VIP I TBM I AIL Access Report I 10.09.18 Issue 0 I Contents & Executive Summary I Page ii of xxx
Executive Summary
The contents of this report include land transport feasibility investigations into achieving access to two sites in North Wales where National Grid are planning to deliver Tunnel Boring Machines (TMBs) as part of a future development scheme known as the Snowdonia Visual Impact Provision (AIP) works to reduce the amount of overhead electricity wires by installation of underground cables. These sites are located on the east and west banks of the Afon Dwyryd estuary east of Porthmadog, Gwynedd, North Wales.
North Mid Wales Trunk Road Agency (NMWTRA), working as managing agents on behalf of Welsh Government, have advised that at present, there is no route for the proposed AILs from the A55 to the Porthmadog area due to the river bridge on the A487 at Bontnewydd being recently assessed and down rated for no vehicles above Construction and Use traffic (44 tonnes). As the Secretary to the MAWR companies (Movement Along Welsh Roads), Wynns have written to NMWTRA and Welsh Government to highlight this issue. As the A487 is part of the strategic trunk road network, the capacity reduction will be a significant issue for ongoing access to the Porthmadog area. It is not clear if there are any suitable alternative routes which could be used to avoid the Bontnewydd issues and work to identify if such exists will be on going.
Wynns have also requested if the Bontnewydd structure can be temporarily bridged over and await a response from NMWTRA on this matter. It is most likely that an operation to lift in bridge rafting equipment would require a road closure and as such, Wynns will report under separate cover once these investigations have been able to clarify if this may be possible in principle.
The above is the main issue to report which of significant concern for AIL access to the locations being considered for the delivery of TBMs.
The two sites were inspected for route negotiability in August of this year, and for the purposes of this investigation have been labelled as VIP Site East and West. These locations can be found in Map 1 attached to Appendix 1 of this report.
Structural clearance has been provided for the local access from the A487 to both sites, notwithstanding the failure at Bontnewydd Bridge on the A487 which is common to both locations.
Road access to the Western site will require the use of the internal haul road which has been identified by National Grid as the preferred site access to the site compound at approx. OS Grid Reference SH 5939 3862.
Site access for the Eastern site is recommended to be from the A487 at Penrhyndeudraeth via the Pont Briwet Bridge which has been upgraded in recent years to provide access to the A496. Although a potential alternative that approaches from the north east from the A487 at Maentwrog could be utilised this is not considered as suitable for access for TBMs due to the narrow section of the A496 south to the delivery site when alternatives exist.
The routes are considered negotiable to both sites. However, as the loads are 5m in width there will be sections throughout the route where full occupation of the highway will be required and careful consideration of escort requirements including movement times and traffic management will be required. This will require more detailed discussions with North Wales Police, NMWTRA and Gwynedd County Council prior to delivery by the appointed haulage contractors.
WSP I 18-954 Snowdonia VIP I TBM I AIL Access Report I 10.09.18 Issue 0 I Contents & Executive Summary I Page iii of xxx
No specific consideration of the internal haul road providing access between various laydown areas in the development area has been included and it is assumed that the developer will design this to be able to accommodate the AILs required. A detailed appraisal of the technical requirements for handling components on-site will be required as the scheme progresses in the future.
There has been no specific consideration of onsite access within the sites themselves with all route investigations ceasing at the point at which the public road access to the site is proposed to be constructed.
The report is intended to be a summary of the Abnormal Indivisible Load (AIL) route access at the current time and is not a guarantee that the route will be cleared in the future. Specific movements will need to be assessed at the time on an individual basis. If any further information is required, it is available on request. WSP I 18-954 Snowdonia VIP I TBM I AIL Access Report I 10.09.18 I Issue 0 I Page 4 of 30
1. Introduction
1.1. The contents of this report include land transport feasibility investigations into achieving access to two sites in North Wales where National Grid (NG) are planning to deliver Tunnel Boring Machines (TMBs) as part of a future development scheme known as the Snowdonia Visual Impact Provision (AIP) works to reduce the amount of overhead electricity wires by installation of underground cables. These sites are located on the east and west banks of the Glaslyn estuary east of Porthmadog, Gwynedd. The TBMs will be Abnormal Indivisible Loads (AIL) in terms of the transportation requirements on the public road network.
1.2. This will see TBM deliveries to the east and west sites that are being proposed as construction site access areas. The TBMs could be delivered via any UK port and transported to North Wales by road.
1.3. This report is a summary of the status of the current AIL access investigations and seeks to present the situation as it currently stands. The issues highlighted in this report as risks to achieving AIL access in the future, will need to be revisited and progressed as the scheme develops.
1.4. This investigation considers the potential land transport routes from the England/Wales Border via the A55 trunk road based on the assumption that movements will take place under Special Types General Order (STGO) Regulations.
1.5. No consideration of site access or the internal haul roads in the development site is included and the route surveys end at the point at which site access is proposed to exit the public highway. A detailed appraisal of the technical requirements for handling components on-site will be required as the scheme progresses in the future.
1.6. The report is intended to be a summary of the AIL route access at the current time and is not a guarantee that the route will be cleared in the future. Specific movements will need to be assessed at the time on an individual basis. If any further information is required, it is available on request.
1.7. The report considers access in terms of AIL transportation only. No allowance is made for Construction and Use and general traffic requirements including traffic management plans that may be associated with the wider development plan.
2. Historical Information
2.1. Movement Along Welsh Routes (MAWR)
2.1.1. The Movement Along Welsh Routes (MAWR) Group is a group consisting of companies with a requirement to move AILs in the North Wales area. Member companies include First Hydro Company, National Grid and Magnox. Each of these companies has a requirement for heavy load access to their associated power stations and substations in North Wales. MAWR meets every year, with representatives of the Welsh Government and local authority highway departments also in attendance, with a remit to discuss issues impacting on heavy load access to power stations and substations. This applies to routes that require AIL access and as such are regarded as being strategically important by MAWR. AIL movement requirements are infrequent but access needs to be maintained at all times to WSP I 18-954 Snowdonia VIP I TBM I AIL Access Report I 10.09.18 I Issue 0 I Page 5 of 30
enable expedient movement in the event of a system failure at a power station or substation resulting in the need for an emergency AIL movement.
2.1.2. It is recommended that as the VIP Project proceeds that representatives from National Grid continue to attend MAWR meetings to update relevant interested parties of future AIL requirements.
2.2. Porthmadog and Trawsfynydd Power Station & Substation
2.2.1. Porthmadog was originally used as the marine access port when Trawsfynydd Nuclear Power Station was constructed in the 1950/60’s. This involved the construction of a dockside crane by the Central Electricity Generating Board (CEGB). This was located to the south of the harbour and is no longer in place, having been removed post construction of the power station. The crane was designed to lift loads from coastal vessels onto awaiting road transport. Once the power station had been commissioned, the crane was taken down and the harbour redeveloped and for any future heavy load movements, a barge berth was created at Pen-y-Cei (also known as The Green), with an associated license agreement for future use.
2.2.2. Since the early 1980s there has been an understanding from CEGB and its successor companies (National Grid and First Hydro) that any heavy AILs to be delivered via Porthmadog would take place via the area identified as “The Green” within the harbour itself.
2.2.3. National Grid retains the former CEGB access agreement with Gwynedd County Council to maintain access for heavy loads at Porthmadog. In principle it is understood that the area at The Green is to be protected to enable future AIL access. This is however an event that has taken place only two times since the agreement was put in place in the early 1980’s and is not a regular operation. There remain logistical issues to resolve to enable access. However, as is discussed in Section 3, Special Order AILs are not required for this project and therefore the focus is on the delivery of items to North Wales by road from the wider UK motorway and trunk road network.
2.2.4. The access to Trawsfynydd from Porthmadog has traditionally been maintained by National Grid in order to enable future delivery of transformers with nett transport weights of up to circa 210te.
2.2.5. Available records indicate that the last movement to Trawsfynydd Substation of Special Order category) took place in 1987. This was for the delivery of a transformer of circa 210te nett weight which was transported on a 14 axle girder frame trailer from Porthmadog at a gross weight of 295te with axle weights of 21.07te.
2.3. Ffestiniog Power Station
2.3.1. In addition to the Trawsfynydd substation delivery detailed previously, Porthmadog has also been used to deliver Special Order loads to Ffestiniog Power Station, and the first part of the route is common to that used for Trawsfynydd. Available records indicate that the last movement to Ffestiniog Power Station of Special Order category took place in 1993. This was for the delivery of a transformer of circa 115te nett which was transported on a 12 axle flattop trailer from a flattop barge at Porthmadog. This vehicle had a gross weight of 158.2te. WSP I 18-954 Snowdonia VIP I TBM I AIL Access Report I 10.09.18 I Issue 0 I Page 6 of 30
2.3.2. Since the 1993 movement deliveries have been undertaken to Ffestiniog by road from Liverpool for transformers of 114te nett weight and below. This has been possible due to road improvements in the last 20 years to the A55 and A487 which have enabled road routing for STGO loads below 150te gross with the most recent delivery of a transformer being in 2009 at a gross weight of 147te gross transported on a 10 axle flattop trailer. This therefore avoids the need for expensive coastal shipping by enabling a road route to be utilised where available.
Library Photograph 1 1993 movement of a 115te transformer to Ffestiniog Power Station about to cross over The Cob at Porthmadog.
2.4. Pentir Substation
2.4.1. Recent deliveries (March 2014) have been undertaken to Pentir Substation by road from Liverpool for reactors of 112te nett weight and below and have not required Special Order permissions. These have been delivered into the region via the A55, A5, and A4244. Pentir Substation does however have SGTs that would be expected to be moved at Special Order category and as such requires that access is maintained from Port Penrhyn.
2.5. Maentwrog Power Station
2.5.1. The most recent delivery (2016) undertaken to Maentwrog Power Station by road for a transformer of 75te nett weight at 109te gross weight which have not required Special Order permissions. This was delivered into the region via the A55, A5, and A4244 to avoid Caernarfon and involved crossing Bontnewydd Bridge which is discussed in Section 7.1 as a structural limitation at present. Maentwrog Power Station is located to the north of the VIP East site on the A496.
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3. Highways England Agreement in Principle and Legislative Requirements
3.1. Definition of Abnormal Indivisible Load (AIL)
3.1.1. The Department for Transport, of which Highways England (HE), formally the Highways Agency (HA), is a government-owned company with responsibility for managing the core road network in England, state that the strict definition of an AIL refers to a load which cannot, without undue expense or risk of damage, be divided into two or more loads for the purpose of carriage on roads and which, owing to its dimensions or weight, cannot be carried on a vehicle which complies in all respects with the ‘standard vehicle regulations’ these are:
The Road Vehicles (Construction and Use) Regulations 1986 (as amended) The Road Vehicles (Authorised Weight) Regulations 1998 (as amended) The Road Vehicles Lighting Regulations 1989 (as amended).
3.1.2. All equipment should be stripped of their ancillaries before they are transported. HE will only accept that further dismantling is not required where it cannot be economically achieved due to the requirement for its construction within specific factory environments or where extremely high tolerances have to be maintained.
3.2. Legislation
3.2.1. Conventional heavy goods vehicles have an operating weight limit of 44 tonnes. The category known as abnormal indivisible loads (AIL) covers those vehicles where the gross weight exceeds 44 tonnes. An Abnormal Load is defined as that which cannot be carried under Construction and Use (C&U) Regulations. Items which, when loaded on the load carrying vehicle exceed the weights encompassed by the C&U Regulations, but do not exceed Special Order Permission Limits, are governed by Special Types General Order (STGO) categories 1 to 3 depending on size. Where dimensions exceed 6.1m in width, 30m in rigid length or 150 tonnes gross weight, Special Order from HE is required. Highways England have issued an aide memoir that explains notification requirements in more detail. This document has been attached as Appendix 3.
3.2.2. Special Order category AIL movements are authorised by the HE Abnormal Loads team, based in Birmingham.
3.2.3. STGO loads orders grant consent for loads that satisfy the following criteria:
Category 1 weight 44 – 50 tonnes and 11.5te axle weights Category 2 weight 50 – 80 tonnes and 12.5te axle weights Category 3 weight 80 – 150 tonnes and 16.5te axle weights Width Restriction 3.0m (C&U) –5m (VR1 Required) – 6.1m (SO Required) Length Restriction 18.65m (C&U) – 30.0m (SO Required)
3.2.4. The TBMs considered within these investigations are expected to be transported at STGO Category 3. Such loads are required to provide two clear working weekdays notice to be given to the Police forces on the proposed route and are required to provide 5 clear working weekdays notice together with an indemnity to the highway and bridge authorities on the route. WSP I 18-954 Snowdonia VIP I TBM I AIL Access Report I 10.09.18 I Issue 0 I Page 8 of 30
3.2.5. As the loads considered in these investigations are within STGO and therefore no specific consideration of Special Order requirements, including the Department for Transports (DfT) Water Preferred Policy for AILs is considered necessary and no specific marine access investigations are included.
3.3. As the loads are not restricted to Special Order requirements they will not necessarily be delivered to a North Wales Port and could arrive via any UK port and travel to the motorway and trunk road network to enter Wales on the A55 trunk road subject to route approval at the time of requirement. It was assumed at the commencement of investigations that this will be feasible without difficulty for the proposed loads as has been the case for STGO loads to Pentir Substation and Ffestiniog Power Station in recent years. The final approach to the sites from the A55 England/Wales border is discussed in terms of structural clearance in Section 7.
4. Abnormal Indivisible Load Movements - Highways Act 1980
4.1. Recovery of Excessive Maintenance Costs - Section 59 Agreements
4.1.1. Section 59 of the Highways Act 1980 allows the highways authority to raise a charge against a user of the highway to cover repair works necessitated by excessively heavy or unusual loads being carried on the road by that user. This provision is typically used where the passage of heavy lorries to and from industrial premises or building sites causes excessive damage to the road, requiring expensive remedial works by the Council. Under Section 59, the Council may charge on such costs to the organisation responsible for the damage, the amount payable being calculated as the excess cost of repair compared to normal maintenance costs for the road. Rather than wait to be charged such excessive repair costs, the Council and the third party may enter into an agreement under Section 59 whereby the third party accepts liability and makes payment of an agreed sum to the Council to cover the excessive repair costs.
4.2. The Removal and Replacement of Street Furniture
4.2.1. Where the removal and replacement of street furniture is required for the mobilisation of out of gauge vehicles into existing sites then these are generally managed under Temporary Traffic Regulation Order (TTRO) and Street Works Legislation. These are normally, but not necessarily, organised by the haulage contractor. These requirements are generally to ensure that the supervisors and operatives are competent and that the works will be carried out to a prescribe standard with the appropriate traffic management in place. In some circumstance the Highway Authority or LA will insist that their preferred contractors will carry out such work.
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5. Plant Dimensions Included within Study Work
5.1. The information included within this report is based around a selection of different manufacturing contractor’s potential equipment which has been made available to Wynns. All details of possible transport dimensions should be treated with caution and be understood to be in need of clarification as the scheme progresses.
5.2. Table 1 shows dimensions of the TBMs that has been included within the study for initial feasibility assessment work. These dimensions have been used to derive indicative transport arrangement drawings for presentation to highway and structural authorities as detailed in Section 7. A 200te mobile crane has also been included as it is expected that this will be required on site also.
Table 1. Selected Items to be considered. Item Weight Diameter/ Length/Depth Notes Width Cutterhead 50te 5m 0.3m
1st Shield Section 30te 5m 5m
2nd Shield Section 20te 5m 5m Could potentially be moved within C&U under 44te gross.
200te Mobile Crane 60te 3m 15.282m
Note: It is assumed that the diameters of 5m are maximum and will not be exceeded. If loads exceed 5m then VR1 permissions will be required.
6. Transport Configurations
6.1. Tunnel Boring Machines
6.1.1. The dimensions of the TBM components expected to require delivery to the sites considered in these investigations is detailed in Table 1 previously discussed. Due to the size of the components it is not possible to transport them under the regulations governing Construction and Use (C&U) vehicles (44 tonne gross, 18.65m long and 2.9m wide). It is therefore necessary to transport within the Special Types General Order (STGO) regulations as previously discussed.
6.1.2. There are numerous haulage contractors with equipment able to carry the TBM compnentes within STGO Category 2 or 3 (between 50-80te or 80te–150te gross) and these have been used to inform and produce the conceptual transport drawing considered within this report. As various haulage contractors are available, competitive tendering for the transport of cable drums is viable. For the general purposes of this investigative work we have produced a transport arrangement considerate of a maximum 50te nett cutter head section at 5m width and the 200te mobile crane as worst case anticipated transport dimensions. WSP I 18-954 Snowdonia VIP I TBM I AIL Access Report I 10.09.18 I Issue 0 I Page 10 of 30
6.1.3. It is assumed that road transport configuration would utilise a bed trailer or low bed type configuration. The following transport drawing has been submitted to structural authorities for comment.
Drawing No 18-954, TC01 – 4 axle stepframe trailer at 79te gross Drawing No 18-954, TC02 – 200te mobile crane at 60te gross
6.2. The physical negotiability of these vehicles is discussed in further detail in Section 8.
6.3. The trailer arrangements provided to the structural authorities for consideration in this investigation have been produced to be considerate and representative of those available in the UK heavy haulage market in terms of their suitability on the potential access route from the A55 to site. The responses to these investigations are discussed in Section 7.
7. Structural Route Information
7.1. Tunnel Boring Machine Access
7.1.1. As the loads are not restricted to Special Order requirements, the cable drums could arrive via any UK port and travel to the A55 by way of the motorway and trunk road network. It is assumed that this will be feasible without difficulty for the proposed loads. The final approach to the Porthmadog study area from the English Border at the A55 Chester bypass has been considered which is a recognised heavy load route, and the routes to the two east and west sites from the main A487 are detailed below.
Preferred Route to TBM West Site From English Border continue A55 westbound to A5/A55 junction Turn left onto A5 Turn right A4244 Bear left at Pentir roundabout on A4244 Turn right A4086 Turn left Class 3 at approx. OS Ref. SH 513 632 Straight ahead at roundabout at Caeathro Turn left on to A487 at Bontnewydd Note 1: We are aware from previous experience that the masonry arch section of the bridge at Bontnewydd (OS grid reference SH 482 598) is unsuitable for AIL movements but the reinforced concrete extension at the northern side is expected to be adequate. Loads must travel on the downstream side of the bridge. Continue A487 to Penmorfa Continue A487 at Tremadog Roundabout Continue A487 Porthmadog Roundabout Continue A487 via Porthmadog bypass to Minffordd Roundabout Turn right High Street Turn right unclassified road at OS Grid Ref. SH 5872 3811 Turn left unclassified road at proposed new site access at approx. OS Grid Ref. SH 5939 3862
Preferred Route to TBM East Site Same as route 1 to Minffordd Roundabout Turn left A487 Eryri Terrace Turn right Cambrian View Continue Penrhyndeudraeth Bridge (Pont Briwet) Turn left A496 Turn right at proposed site access at approx. OS Grid Ref. SH 6242 3795
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Maentwrog Diversion to East Site Same as route 1 to A487 Eryri Terrace Continue A487 Turn right A496 to Maentwrog Continue A496 Turn left at proposed site access at approx. OS Grid Ref. SH 6242 3795 Note: At Maentwrog it may be necessary depending on the final size of load to contraflow the one way system enabling access to A496.
7.1.2. The routes have been cleared by the structural authorities detailed below.
Canal & Rivers Trust Highways England Historic Railways Estate Network Rail Gwynedd County Council
7.1.3. North Mid Wales Trunk Road Agency (NMWTRA) have advised (emails 29.8.18) that the A487 Bontnewydd Bridge has recently been down rated to Construction and use (44te) loads only at present, although this remains under review. This causes significant concerns in terms of getting AILs into the area on what has long been regarded as the most suitable heavy load route from the north whether via the A487 in full or via the diversion from the A55 at Banger Services on the A5, A4244 and A4086. Such a significant restriction will be a major concern to many organisations in the region as it will impact on much smaller STGO AILs and is not solely an issue for the heavier end of the electricity supply industry.
7.1.4. Traditionally it has always been understood that it is necessary for heavy AILs to avoid the old masonry arch section and to travel on the reinforced concrete extension at the northern side with the loads on the downstream side of the bridge and this has been the basis of route clearance work and actual notifications over the years.
7.1.5. For the high end STGO loads there would initially appear very little scope for alternative routes to sites that approach from the south and east although this could be investigated further and clarification has been sought from Welsh Government, North Wales Police and NMWTRA as to the suitability of potential diversion routes to avoid the problem for STGO loads.
7.1.6. Wynns have significant interest in the A487 heavy load route in our role as consultants to clients in the electricity supply industry and also as the Secretary of the of Movement Along Welsh Routes (MAWR) Group. We aware from informal discussions over the time since the last meeting of MAWR in November 2017 that there has been an assessment taking place over recent months which is what we presume has led to this significant weight restriction being imposed. We have asked for confirmation that within this assessment potential remedial measures for AILs such as travelling at crawl speed, no stopping, certain alignment requirements, no HA loading, have been considered.
7.1.7. It may be prudent to also discuss potential temporary measures such as bridging units, propping etc. These would be subject to detailed engineering proposals technically and would also have an impact on other road users due to the potential need to carry out such works under a road closure and further information is being sought from NMWTRA and Welsh Government on this option. The possible solutions would depend on the bridge length of span and method of support. Available records indicate that the bridge has a 15m span and we have experience of bridging structures in excess of this. WSP I 18-954 Snowdonia VIP I TBM I AIL Access Report I 10.09.18 I Issue 0 I Page 12 of 30
7.1.8. Of specific concern are the following sites and projects that our clients require AIL access to in addition to this specific cable drum project:
Ffestiniog Power Station (First Hydro Company) – Transformer access at top end STGO for transformers in excess of 100te nett weight. Also other items that would be moved more generally at STGO. Trawsfynydd Substation (National Grid) – Although Special Order transformers in excess of 150te nett may be expected to be delivered via Porthmadog this is not without difficulty. In addition, other STGO loads may need to route via A487. Potential new SMR Power Station at Trawsfynydd (Welsh Government/Snowdonia Enterprise Zone development project) – Although Special Order loads of various components may be expected to be delivered via Porthmadog this is not without difficulty. In addition, other STGO loads may need to route via A487. Proposed Bryncir Substation (National Grid) – Although Special Order transformers may be expected to be delivered via Porthmadog this is not without difficulty and it may be easier and preferable to deliver them from Port Penrhyn, subject to route. In addition, other STGO loads may need to route via A487. Maentwrog Power Station (Magnox) – STGO loads. Most recent was 75te nett transformer in approximately 2016. Glaslyn Cable Feed Project (National Grid via consultants WSP) – Cable drums at STGO. Snowdonia Visual Impact Provision (National Grid via consultants WSP) – Tunnel Boring Machines (TBM)
7.1.9. Wynns and MAWR would hope that this is a serious enough issue to be a priority for NMWTRA and Welsh Government but it may take a period of time for permanent design of and facilitation of remedial works to be agreed and carried out. We have requested that MAWR are consulted on any future permanent strengthening schemes that may be proposed and will continue to monitor the situation but at present there is not access to loads in excess of 44te gross to the Porthmadog area.
7.1.10. The preferred route identified is a recognised diversion via the A5, A4244 and A4086 that avoids the A487 Caernarfon. North Wales Police have historically requested that loads avoid Caernarfon due to the narrow nature of some of the A487 and the need to use the one way system. The proposed diversion route is acceptable for the cable drum loads and therefore the Caernarfon option is not discussed further in this report but it could be utilised for the proposed loads with approval from NMWTRA and North Wales Police if necessary.
7.1.11. The proposed A487 Caernarfon to Bontnewydd Bypass is planned in forthcoming years which may assist in the future for access into the region. However, for current purposes the status of the route as it is now has been considered.
7.1.12. MAWR have previously highlighted required loadings for the existing Ffestiniog Power Station requirements should be included in the new bypass and it is understood the new road will be accommodating of this.
7.1.13. It is noted that both Gwynedd County Council and Network Rail have confirmed the routes are structurally acceptable. However, there is some confusion over who is responsible for the Minffordd Rail Bridge (OS Ref SH 5996 3852) on the A497 which is on the proposed route to the west site. Network Rail have advised that this is not their structure but Wynns are the view based on previous movements in the area that it is a Network Rail structure and clarification of this is being sought. This has been a recurring issue over recent years WSP I 18-954 Snowdonia VIP I TBM I AIL Access Report I 10.09.18 I Issue 0 I Page 13 of 30
and no significant problems are expected structurally in terms of the bridge which has been crossed by heavy loads in the past but ownership does need to be clarified.
7.1.14. In addition Network Rail have cautioned that they regularly inspect and assess bridges and occasionally have to revise the permitted load carrying capacity, as such, it would be advisable to contact Network Rail again closer to the movement date to ensure that their bridges are still adequate. It will therefore be necessary to engage further with Network Rail in respect to access over Minffordd Rail Bridge as the project progresses when routing to the west TBM delivery location.
7.1.15. The potential use of the new by-pass would open up route options from the north and Port Penrhyn that are currently restricted due to physical dimensions which present concerns to North Wales Police.
7.1.16. North Wales Police have been approached for comment on the proposed routes submitted for consultation and have yet to provide a formal response.
8. Route Negotiability
8.1. Route to TBM West Site
8.1.1. The proposed route from the A55/A5 junction to the West Site is detailed in Section 7 and illustrated on the maps provided in appendix 1 of this report. The negotiability of the proposed routes is discussed in the following notes and photographs.
8.1.2. The route via Pentir to Bontnewyedd has been described as the preferred route from the A55 to the general site area. This is also an established heavy load route and has been used for the delivery of much larger abnormal loads to Ffestiniog Power Station and also in part for Pentir substation and Dinorwig Power Station.
8.1.3. The route was inspected from the A55 during August 2018.
Photograph 1 Vehicle moves away from camera. Exiting A55 on to the A5 roundabout. WSP I 18-954 Snowdonia VIP I TBM I AIL Access Report I 10.09.18 I Issue 0 I Page 14 of 30
Photograph 2 Reverse of A5/A4244 roundabout. Vehicle moves towards camera. Negotiable.
Photograph 3 A4244/A4086 Junction. Vehicle moves away from camera and turns right on to the A4086. Negotiable.
Photograph 4 A4086/A4244 Junction. Vehicle enters photo from A4244, turns right on to the A4086 and exits behind camera. WSP I 18-954 Snowdonia VIP I TBM I AIL Access Report I 10.09.18 I Issue 0 I Page 15 of 30
Photograph 5 A4086 and unclassified road junction at Pont-rug. Vehicle moves away from camera, turns left unclassified road. No negotiability issues foreseen.
Photograph 6 Reverse angle of left turns on to unclassified road at Pont-rug. Negotiable.
Photograph 7 A4085 roundabout in Caeathro. Vehicle moves away from camera, and travels straight over roundabout continuing on the unclassified road. Negotiable. WSP I 18-954 Snowdonia VIP I TBM I AIL Access Report I 10.09.18 I Issue 0 I Page 16 of 30
Photograph 8 Unclassified road in to Bontnewydd. Vehicle moves away from camera.
Photograph 9 Unclassified road/Pwllheli Road roundabout in Bontnewydd. Vehicle moves away from camera, turns left at roundabout on to A487. Negotiable.
Photograph 10 A487/A499 Roundabout. Vehicle moves away from camera. Negotiable. WSP I 18-954 Snowdonia VIP I TBM I AIL Access Report I 10.09.18 I Issue 0 I Page 17 of 30
Photograph 11 A487/ Lôn Cefn Glyn Roundabout. Vehicle moves away from camera. Negotiable.
Photograph 12 East on A487. Vehicle moves away from camera. Negotiable although full occupation of the highway will be required and careful consideration of escort requirements including movement times and traffic management will be required.
Photograph 13 East on A487. Vehicle moves away from camera. Negotiable although full occupation of the highway will be required and careful consideration of escort requirements including movement times and traffic management will be required. WSP I 18-954 Snowdonia VIP I TBM I AIL Access Report I 10.09.18 I Issue 0 I Page 18 of 30
Photograph 14 Approaching A487/A498 roundabout. Vehicle moves away from camera, continues A487.
Photograph 15 A487/High Street roundabout. Vehicle moves away from camera continues A487.
Photograph 16 East on A487 Porthmadog Bypass. Vehicle moves away from camera. WSP I 18-954 Snowdonia VIP I TBM I AIL Access Report I 10.09.18 I Issue 0 I Page 19 of 30
Source; Google, licence no. JCPM2Z11CKENWEQ
Photograph 17 Minffordd Roundabout. Vehicle moves away from camera, turns right High Street.
Photograph 18 Reverse of A487/High Street Roundabout. Vehicle moves towards camera upon exiting roundabout.
Photograph 19 A497 West on High Street. Vehicle moves towards camera. Negotiable although full occupation of the highway will be required and careful consideration of escort requirements including movement times and traffic management will be required. WSP I 18-954 Snowdonia VIP I TBM I AIL Access Report I 10.09.18 I Issue 0 I Page 20 of 30
Source; Google, licence no. JCPM2Z11CKENWEQ Photograph 20 A497 Right turn at OS Grid Ref. SH 5872 3811. Vehicle moves away from camera and turns right.
8.1.4. The surveyor has recommended a swept path assessment be carried out to confirm negotiability of the right turn from the A497 to the unclassified road that leads to the final aprpach to VIP Site West. If this is not considered feasible then the surveyor recommends driving past the junction and reversing on to the unclassified road to the proposed new site access approximately 700 meters. This would avoid the need to travel via Porthmadog town centre.
Photograph 21 Unclassified road. Vehicle moves away from camera.
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Photograph 22 Vehicle moves away from camera. Full occupation of the highway necessary. Negotiable although full occupation of the highway will be required and careful consideration of escort requirements including movement times and traffic management will be required.
Photograph 23 Potential new site access for TBM West Site at approx. OS Grid Reference SH 5939 3862.
8.1.5. It is understood from consideration of sketch number PDD-33494-TUN-SK01-001 (attached in Appendix 2) that the TBM proposed construction laydown area is to be accessed via a new internal haul road to be constructed from the point shown in photograph 23 above. It is assumed that the developer will design the internal haul road to be able to accommodate the AILs required. The transport arrangement drawings provided in Appendix 2 can be used for indicative ground loadings and turning circles that are required.
8.2. Route to TBM East Site
8.2.1. The proposed route from the A55/A5 junction to the East Site is detailed in Section 7 and illustrated on the maps provided in appendix 1 of this report. The negotiability of the proposed route is discussed in the following notes and photographs. The preferred route is to exit the A487 trunk road at Penrhyndeudraeth and approach the development site from the south west on the A496 at Trem-y-Garth.
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Photograph 24 Minffordd Roundabout. Vehicle moves away from camera, continues left onto A487. Negotiable.
Photograph 25 A487/Cambrian View. Vehicle moves away from camera, turns right Cambrian View.
Photograph 26 A487/Cambrian View. Vehicle moves away from camera, turns right Cambrian View. Negotiable although full occupation of the highway will be required and careful consideration of escort requirements including movement times and traffic management will be required. WSP I 18-954 Snowdonia VIP I TBM I AIL Access Report I 10.09.18 I Issue 0 I Page 23 of 30
Photograph 27 East on Pont Briwet. Vehicle moves away from camera.
Photograph 28 East on Pont Briwet. Vehicle moves away from camera.
8.2.2. The bridge at Pont Briwet has been significantly upgraded in recent years and confirmed as structurally acceptable by Gwynedd County Council who also advised at the commencement of the investigations that they considered this the most suitable access route to the proposed TBM delivery location on the A496.
Photograph 29 Reverse angle of Pont Briwet/A496 Junction. Vehicle enters junction middle right, turns left, exits behind camera. No negotiability issues foreseen. WSP I 18-954 Snowdonia VIP I TBM I AIL Access Report I 10.09.18 I Issue 0 I Page 24 of 30
Photograph 30 North East on the A496. Vehicle moves away from camera. Negotiable although full occupation of the highway will be required and careful consideration of escort requirements including movement times and traffic management will be required.
Photograph 31 North East on the A496. Vehicle moves away from camera.
Photograph 32 Proposed TBM East Site Access. Site access to be designed to accommodate proposed AIL delivery vehicles. WSP I 18-954 Snowdonia VIP I TBM I AIL Access Report I 10.09.18 I Issue 0 I Page 25 of 30
8.2.3. An alternative route was looked at via Maentwrog although this is deemed unsuitable due to the turn from the A487 to the A494 at Maentwrog which has a restricted left turn adjacent to a property.
Photograph 33 A487/A496 junction. Left turn will not be negotiable for AIL delivery vehicles.
8.2.4. It may be feasible to avoid the left turn highlighted by contraflowing the old bridge at the junction. Although Maentwrog has been accessed via this route in the past the section south on the A496 to the proposed TBM delivery location is narrow with multiple bends. Although the route could be considered if absolutely necessary it is not as suitable as that described in 8.1 that approaches from the south and therefore it is recommended that it is not considered further at this stage.
9. Summary and Conclusions
9.1. As the loads will be moved under STGO Category 3 legislation it is assumed that the road route to the A55/A5 junction will be accessible from a suitable UK port of delivery.
9.2. At present there is no access to the development area due to a significant downgrading of Bontnewydd Bridge on the A487 to C&U traffic only (44te gross). This has been advised by NMWTRA and Wynns are in discussions with them to find a way forward as this is a strategic route affecting many sites in North Wales. The restriction is on an established heavy load route and the importance of this has been highlighted to NMWTRA and Welsh Government.
9.3. Notwithstanding the Bontnewydd Bridge restriction, the proposed routes have been structurally cleared for all loads from the A487 to the two development sites where TBMs are required to be delivered in terms of both East and West sites in terms of local access requirements.
9.4. The route surveys carried out have found that access is possible to both the East and West sites in terms of physical negotiability, although the West site will require the delivery vehicles to use new site access points and use of the proposed internal haul road.
9.5. There are no major problems with access to the East site although the new site access points will need to be carefully considered. WSP I 18-954 Snowdonia VIP I TBM I AIL Access Report I 10.09.18 I Issue 0 I Page 26 of 30
9.6. As the loads are 5m in width there will be sections throughout the route where full occupation of the highway will be required and careful consideration of escort requirements including movement times and traffic management will be required. This will require more detailed discussions with North Wales Police, NMWTRA and Gwynedd County Council prior to delivery by the appointed haulage contractors.
9.7. The route investigations detailed are a view of the current status of the proposed heavy load route options only and do not consider any other components or traffic to the site.
9.8. The report is intended to be a summary of the AIL route access at the current time and is not a guarantee that the route will be cleared in the future. Specific movements will need to be assessed at the time on an individual basis. If any further information is required, it is available on request.
WSP I 18-954 Snowdonia VIP I TBM I AIL Access Report I 10.09.18 I Issue 0 I Page 27 of 30
Appendix 1
Maps
Key
Route to TBM West Site A
Route to TBM East Site B
Maentwrog Diversion
Point of Interest
Proposed Laydown Areas
B
A
0 06.09.18 First Issue
Rev Date Amendments: Revisions
Wynns Ltd. Independent
Transportation
Engineers
Shaftesbury House, 2 High Street, Eccleshall, Stafford, ST21 6BZ. Tel: (01785) 850411
Client: Manchester Technology Centre, Oxford Road, Manchester, M1 7ED Project:
Snowdonia Visual Impact Provision
Title: Map 1 – Routes to Proposed Site Locations
Drawing Status: Final Report Scale (A4): Drawn by: Checked by: NTS DMW ARP
Ref No.: Sheet: Rev.: A487 to Porthmadog WSP-VS-Map1 1 of 3 0
© Wynns Ltd. This drawing is not to be reproduced in whole or in part, in any form or by any means, without prior written consent.
© Crown Copyright. All rights reserved. Licence No AL100035894
Key
Route to TBM West Site A
Route to TBM East Site B
Maentwrog Diversion
Point of Interest
Proposed Laydown Areas
A487 from Bontnewydd
B
A
0 06.09.18 First Issue
Rev Date Amendments: Revisions
Wynns Ltd. Independent
Transportation
Engineers
Shaftesbury House, 2 High Street, Eccleshall, Stafford, ST21 6BZ. Tel: (01785) 850411
Client: Manchester Technology Centre, Oxford Road, Manchester, M1 7ED Project:
Snowdonia Visual Impact Provision
Title: Map 1 – Routes to Proposed Site Locations
Drawing Status: Final Report Scale (A4): Drawn by: Checked by: NTS DMW ARP
Ref No.: Sheet: Rev.: WSP-VP-Map1 2 of 3 0
© Wynns Ltd. This drawing is not to be reproduced in whole or in part, in any form or by any means, without prior written consent.
© Crown Copyright. All rights reserved. Licence No AL100035894
Key
Route to TBM West Site A
Route to TBM East Site B
Maentwrog Diversion
Point of Interest
Proposed Laydown Areas
B
A
0 06.09.18 First Issue
Rev Date Amendments: Revisions
Wynns Ltd. Independent
Transportation
Engineers
Shaftesbury House, 2 High Street, Eccleshall, Stafford, ST21 6BZ. Tel: (01785) 850411
Client: Manchester Technology Centre, Oxford Road, Manchester, M1 7ED Project:
Snowdonia Visual Impact Provision
Title: Map 1 – Routes to Proposed Site Locations
Drawing Status: Final Report Scale (A4): Drawn by: Checked by: NTS DMW ARP
Ref No.: Sheet: Rev.: WSP-VP-Map1 3 of 3 0
© Wynns Ltd. This drawing is not to be reproduced in whole or in part, in any form or by any means, without prior written consent.
© Crown Copyright. All rights reserved. Licence No AL100035894
WSP I 18-954 Snowdonia VIP I TBM I AIL Access Report I 10.09.18 I Issue 0 I Page 28 of 30
Appendix 2
Drawings & Transport Configurations
Site access road, to be constructed
Boundary of field
Construction compound (Indicative size for reception shaft)
Shaft (12.5m diameter) Headhouse Construction compound (Indicative size for drive shaft)
Boundary of field
Access road to Snowdonia Visual Impact Provision be constructed Provisional Shaft Locations & Construction Compounds Shaft (15m diameter) Sketch for information only Headhouse PDD-33494-TUN-SK01-001 AJW – 06/03/2018
WSP I 18-954 Snowdonia VIP I TBM I AIL Access Report I 10.09.18 I Issue 0 I Page 29 of 30
Appendix 3
Highways England Aid Memoir
Aide Memoire for notification requirements for the movement of Abnormal Indivisible Loads or vehicles by road when not complying with The Road Vehicles (Construction and Use) Regulations 1986 (commonly known as C & U)
Weight Gross weight of vehicle carrying the load 2 clear days notice with indemnity to Road exceeding C & U limits up to 80,000kgs and Bridge Authorities. (78.74 tons) Gross weight of vehicle carrying the load 2 clear days notice to Police and 5 clear days exceeding 80,000kgs up to 150,000kgs with indemnity to Road and Bridge (147.63 tons) Authorities. Gross weight of vehicle carrying the load Highways England Special Order* plus 5 exceeding 150,000kgs (147.63 tons) clear days notice to Police and 5 clear days notice with indemnity to Road and Bridge Authorities
Width C & U loads:- width exceeding 2.9m 2 clear days notice to Police (9ft 6ins) up to 4.3m (14ft 1 ins)
STGO loads:- width exceeding 3.0m (9ft 10ins) up to 5.0m (16ft 5ins) Width exceeding 5.0m (16ft 5ins) up to 6.1m Highways England form VR1** plus 2 clear (20ft) days notice to Police Width exceeding 6.1m (20ft) Highways England Special Order* plus 5 clear days notice to Police and 5 clear days notice with indemnity to Road and Bridge Authorities
Length C&U loads:- length exceeding 18.65m 2 clear days notice to Police (61ft 2in) up to 27.4m (90ft) - See C&U Regulations 1986 for definition of length
STGO loads:- length exceeding 18.75m (61ft 6 ins) - See part 2, article 12 of the Road Vehicles (Authorisation of Special Types) (General) Order 2003 (Commonly known as STGO) for definition of length Overall length of a part 2 vehicle-combination 2 clear days notice to Police exceeding 25.9m (85ft) Maximum length exceeding 30.0m Highways England Special Order* plus 5 (98ft 5ins) clear days notice to Police and 5 clear days – see STGO Schedule 1, part 4, paragraph notice with indemnity to Road and Bridge 25 for definition of maximum length Authorities.
NB For some very light loads, such as yacht masts, that are moved on conventional motor vehicles not exceeding 12 tonnes gross weight or trailers not exceeding 10 tonnes gross weight, a Highways England Special Order* will be required if the rigid length exceeds 27.4m (89ft 11ins)
NOTE 1 “Clear days Notice” excludes Saturdays, Sundays or a public holiday in any part of Great Britain in relation to movements authorised by the Special Types General Order only, there being no such exclusion in Special Orders unless specifically stated.
NOTE 2 There is no statutory limit governing the overall height of a load, however, when applying for a Special Order or VR1 it should, wherever possible, not exceed 4.95m (16ft 3ins) in order that the maximum use can be made of the motorway and trunk road network.
NOTE 3 The notification requirements for mobile cranes can be found in the Road Vehicles (Authorisation of Special Types) (General) Order 2003, statutory instrument number 1998 (Part 2 Articles 10 to 18), which is available on the OPSI website: http://www.legislation.gov.uk/uksi/2003/1998/contents/made
NOTE 4 Application to move Special Types or Special Purpose vehicles, such as very large agricultural vehicles, that may not be fully permitted by the Construction & Use (C&U) Regulations or fall outside the scope of the Special Types General Order should be made to the Vehicle Certification Agency (VCA). Their website is at http://www.dft.gov.uk/vca/
*A Special Order application can be completed and submitted online at www.highways.gov.uk/esdal. The Special Order application form BE16 can also be downloaded and e-mailed to the address below. Approval is not automatic and is at the discretion of the Highways England abnormal loads team acting on behalf of the Secretary of State for Transport. To ensure that the necessary clearances can be obtained in good time from the Police, Highway and Bridge Authorities, you should request permission for the move by returning the completed form 10 weeks prior to the scheduled date of the move. In fact you cannot apply too early and we invite manufacturers or hauliers to contact us at pre tender stage, before making a financial commitment to supply the load, to check whether permission would be granted.
** A VR1 application can be completed and submitted online at www.highways.gov.uk/esdal. The form can also be downloaded but must not be e-mailed or faxed because the VR1 form is a legal document and so we must receive the original signed form. Approval is not automatic and is at the discretion of the Highways England abnormal loads team acting on behalf of The Secretary of State for Transport. To ensure that the necessary formalities can be completed in good time, you should request permission for the move by posting the completed form 2 weeks prior to the date of the scheduled move. Again, you cannot apply too early and we invite manufacturers or hauliers to contact us at pre tender stage, before making a financial commitment to supply the load, to check whether permission would be granted.
Forms and enquiries to: Highways England Abnormal loads team 9th Floor, The Cube 199 Wharfside Street Birmingham B1 1RN
E-mail: [email protected] Tel: 0300 470 3004
WSP I 18-954 Snowdonia VIP I TBM I AIL Access Report I 10.09.18 I Issue 0 I Page 30 of 30
Appendix 4
Selected Correspondence
Daisy Wynn
From: King Steven Gruffudd (CEFNFFYRDD)
Follow Up Flag: Follow up Flag Status: Flagged
Hi Daisy,
Sorry for any delay.
At this point in time I have the following comments:
The A487T north of Caernarfon is a North Wales Police prohibited route so you will need to contact them regarding this. Even if the A487T north of Caernarfon is avoided, then A487T Bontnewydd bridge is currently a prohibited structure and I have no information on any works in the pipeline to rectify this. The Bontnewydd / Caernarfon bypass could be underway or completed. As the loads are up to 5m wide then cars will need to be moved at Penmorfa village and at the eastern end of Penrhyndeudraeth. We will need to apply for an order 12 weeks beforehand. Traffic will need to be stopped at the pinch point just to the west of the Oakley Arms, Maentwrog. The presumption is that a police escort will be used.
Thanks
Steve
Steven Gruffudd King LLB PGDip Swyddog Meddiannaeth y Rhwydwaith a Llwythau Annormal / Network Occupancy and Abnormal Loads Officer Asiant Cefnffyrdd Gogledd a Chanolbarth Cymru North & Mid Wales Trunk Road Agent Neuadd y Sir, Aberaeron SA46 0AT 01545 571960 [email protected]
From: Daisy Wynn
Hi Steve,
I’ve just tried to get hold of you regarding the below enquiry I sent at the end of last month.
Have you managed to give this anymore consideration?
We are hoping to complete our reporting next week so would appreciate if you could get something over to me as soon as possible.
Hope you have a great weekend.
Best wishes, Daisy
From: King Steven Gruffudd (CEFNFFYRDD)
Hi Daisy,
Just a little note to say that we are considering this. At a first glance the two main issues you have are the A487T north of Caernarfon and the A487T at Bontnewydd Bridge. I am not sure what state Caernarfon bypass will be at the time of your movements – hopefully completed but will get back to you when I have more info.
Thanks
Steve
Steven Gruffudd King LLB PGDip Swyddog Meddiannaeth y Rhwydwaith a Llwythau Annormal / Network Occupancy and Abnormal Loads Officer Asiant Cefnffyrdd Gogledd a Chanolbarth Cymru North & Mid Wales Trunk Road Agent Neuadd y Sir, Aberaeron SA46 0AT 01545 571960 [email protected]
From: Daisy Wynn
2 Daisy Wynn
From: King Steven Gruffudd (CEFNFFYRDD)
Hi Andy,
As requested:
The A487T Bontnewydd bridge is ‘Pen y Bont Bridge’ located at SH 48279 59866.
It was assessed recently as only suitable for C&U only, but this is being reviewed.
Thanks
Steve
Steven Gruffudd King LLB PGDip Swyddog Meddiannaeth y Rhwydwaith a Llwythau Annormal / Network Occupancy and Abnormal Loads Officer Asiant Cefnffyrdd Gogledd a Chanolbarth Cymru North & Mid Wales Trunk Road Agent Neuadd y Sir, Aberaeron SA46 0AT 01545 571960 [email protected]
1 Daisy Wynn
From: Chapman Jonathan (YGC)
Follow Up Flag: Follow up Flag Status: Completed
Morning Andrew,
I have marked up the attached indicating the extent of the public rights of way around the Cable Drum B location. On the alternative route past the football ground, just after turning of the Porthmadog Bypass, the road passes over a twin box culvert. This structure was built as part of the bypass around 2011 and so will able to carry the proposed loads.
With regards to all other routes off the trunk road network there is only one structure on Drum Route D. This structure is adequate to carry the proposed vehicles.
Cofion/Regards,
Jonathan Chapman, MEng CEng MICE Prif Beiriannydd / Principal Engineer
Swyddfa'r Cyngor, Stryd y Jêl, Caernarfon, Gwynedd, LL55 1SH t: 34481 | 01341 424 481 (Dolgellau) / 32311 | 01286 679 243 (Caernarfon) e: [email protected]
From: Andrew Pearce
Jon,
Thank you for your time during our telephone conversation on this today. You will no doubt get the cable drum and tunnel boring machine loads that my colleague Daisy has sent to authorities for consideration only last week via the formal channels but for info please see a copy of that sent to Rhys on this current project.
In the meantime can you clarify the extent of the public highway on the route labelled Cable Drum B Route as attached as we discussed? I also attached an extract of mapping data from my client detailing the potential site access points we are looking at. My understanding is that the public highway ends to the west of the level crossing at approximate OS Ref SH 5739 3963. Therefore for the loads to use the remainder of the road/bridleway and the level crossing the each private land owner would need to be contacted. We are already in discussions with the Welsh Highland railway/Ffestiniog Railway Company on the issue of using the level crossing.
1 Daisy Wynn
From: Nicholson Katie
Follow Up Flag: Follow up Flag Status: Completed
Hi Daisy,
Your proposed routes do not affect any Network Rail owned road over rail bridges or tunnels therefore we have no objection to them.
Please note we only check the load carrying capacity of Network Rail owned road over rail bridges affected we do not check anything else including: • Load carrying capacity of level crossings • Clearance to bridge parapets • Clearance under a rail bridge • Clearance to overhead wires at level crossings
Just so you are aware, one of your sites is very near the structure below, so if the route changes to cross this, we will need to be notified.
Structure: DJP/B/117-73.25 Road Name: Road From Osmond Terrace Passing Syenite Terrace And Erw Wen To Bwlch Bryn Road, Penrhyndeudraeth (View Map)
Indicative capacities: STGO 1: 50 STGO 2: 80 STGO 3: 120 Crane Cat A: 36 Crane Cat B: 63 Crane Cat C: 67
If you have any further questions please let us know.
Many Thanks
Katie Nicholson Abnormal Loads Assistant Abnormal Loads Help Desk: 01908 783 140
Abnormal Loads | National Records Group | Route Services The Quadrant | Elder Gate | Milton Keynes | MK9 1EN W http://www.networkrail.co.uk/abnormal-indivisible-road-loads/
1 Daisy Wynn
From: Howell, Tania
Follow Up Flag: Follow up Flag Status: Completed
Hi Daisy,
Wow – you’ve certainly made me earn my keep with this one!!
I’ve looked at all the options……
There’s a twin-bore tunnel passing beneath the A487 (at an oblique angle) about 2/3 of the way between the A55 and the A4087/B4547/A487 roundabout. The portals for this are a long way off the road, and there appears to be plenty of fill above them, so they should be OK for the specified vehicles.
I have nothing else on any of the other roads specified.
Cheers for now Tania
Tania Howell Abnormal Loads Officer Jacobs DDI: 0118 946 8911
If your mail concerns abnormal load movements, please reply to [email protected]
From: Daisy Wynn [mailto:[email protected]] Sent: 25 July 2018 15:21 To: [email protected]; Lisa Wheelwright-Brown ([email protected])
Dear All,
I’m writing with regard to a new route enquiry for several locations in North Wales requiring the delivery of cable drums, tunnel boring machine components and a mobile crane.
These deliveries are related to two separate projects; Glaslyn Cable Feed and Snowdonia Visual Impact Provision.
1 Daisy Wynn
From: Lisa Wheelwright-Brown
Hi Daisy
Hope you are well?
The proposed routes attached do not affect the Canal & River Trust’s infrastructure.
Kind Regards
Lisa Wheelwright-Brown Technical Administrator
T 0113 2005759 (6259) E [email protected]
Canal & River Trust Fearns Wharf, Neptune Street, Leeds, LS9 8PB
canalrivertrust.org.uk
@canalrivertrust
/canalrivertrust
/canalrivertrust
From: Lisa Wheelwright-Brown Sent: 30 July 2018 11:58 To: Abnormal Loads
1