Triton Knoll Offshore Wind Farm Limited Electrical System Outline Traffic Management Plan October 2014
RWE Innogy UK Triton Knoll TMP Copyright 2014 RWE Innogy UK Ltd All pre-existing rights reserved. This document is supplied on and subject to the terms and conditions of the Contractual Agreement relating to this work, under which this document has been supplied, in particular: Confidentiality This document is confidential. Liability In preparation of this document RWE Innogy UK has made reasonable efforts to ensure that the content is accurate, up to date and complete for the purpose for which it was contracted. RWE Innogy UK makes no warranty as to the accuracy or completeness of material supplied by the client or their agent. Other than any liability on RWE Innogy UK detailed in the contracts between the parties for this work RWE Innogy UK shall have no liability for any loss, damage, injury, claim, expense, cost or other consequence arising as a result of use or reliance upon any information contained in or omitted from this document. Any persons intending to use this document should satisfy themselves as to its applicability for their intended purpose. The user of this document has the obligation to employ safe working practices for any activities referred to and to adopt specific practices appropriate to local conditions.
RWE Innogy UK Triton Knoll TMP CONTENTS 1. Introduction 2 1.1. Purpose of the outline TMP 2 1.2. Scope of outline TMP 2 1.3. Structure of final TMP 2 1.4. Enforcement of final TMP 3 2. Triton Knoll Electrical System Project Description 3 2.1.1. Cable Route 3 2.1.2. Landfall 3 2.1.3. Intermediate Electrical Compound 3 2.1.4. Substation 3 2.2. Cable route construction and installation 4 2.2.1. Open-cut trenching 4 2.2.2. Horizontal Directional Drilling (HDD) 4 2.2.3. Other Crossings 4 2.3. Construction programme 5 3. General Principles 6 3.1. Pre and post construction surveys 6 3.2. Monitoring 7 4. Construction Traffic 7 4.1. Construction access routes for HGV construction traffic 7 4.2. Construction access route signage 7 4.3. Site Access 7 4.4. Timing and phasing of construction traffic 8 4.5. Abnormal loads 8 4.6. Pedestrian Management 8 4.7. Temporary road closures and diversions 8 4.8. Signage 8 4.9. Contractors travel and parking 8
1. Introduction Triton Knoll Offshore Wind Farm Limited (TKOWFL) was granted development consent for the Triton Knoll array in July 2013. The array will be located approximately 33km off the Lincolnshire coast, shown in Figure 1.1. This outline Traffic Management Plan (TMP) relates to the onshore Triton Knoll Electrical System (TKES) works for the TKOWF, located within the districts of East Lindsey and Boston Borough, in the County of Lincolnshire. 1.1. Purpose of the outline TMP The outline TMP will set out key traffic management measures that will form the basis for discussions with Boston Borough Council, East Lindsey District Council, Lincolnshire County Council and interested members of the community regarding the approach that will be taken by TKOWFL to managing the potential impacts of construction traffic during the construction phase of the Electrical System. The final TMP will: Take into account route surveys, assessment and evaluations undertaken to date; Identify any road improvement works required; Include detailed management measures to control numbers, types and timings of vehicle movements; Identify practical and viable construction access routes; and Give consideration to noise sensitive receptors and the mitigation measures set out in the Noise and Vibration Management Scheme, a document that will form part of the Electrical System Code of Construction Practice. An updated outline TMP will be included in the Electrical System application for development consent. The draft Development Consent Order will include a requirement for a TMP to be agreed with the Local Authorities before works start on site and construction to be undertaken in accordance with the agreed TMP. The final TMP will be written in accordance with the outline TMP. The final TMP will be produced by the contractor appointed to undertake the TKES works and agreed with the relevant local authorities (Boston Borough Council, East Lindsey District Council and Lincolnshire County Council) prior to the start of relevant phases of work. TKOWFL will work with all contractors, sub-contractors and their suppliers to ensure compliance with the relevant provisions of the final TMP. These requirements will be incorporated into the construction work contracts for the onshore elements of the TKES. TKOWFL will work with the relevant Local Authorities to ensure appropriate resourcing is in place during the construction phase to monitor compliance with the provisions of the final TMP. 1.2. Scope of outline TMP This outline TMP relates to the onshore elements of the TKES for the proposed Triton Knoll Offshore Wind Farm (TKOWF), landward of Mean Low Water Spring. This document does not relate to offshore works seaward of Mean Low Water Springs, or any works above Mean Low Water Springs that are principally marine activities. The outline TMP sets out a series of construction vehicle management controls in one cohesive document for the onshore works and formalises commitment made to the Local Authorities and statutory consultees in the Environmental Statement. 1.3. Structure of final TMP The following sections set out the principles for the final TMP. Feedback on the principles set out in this document is welcomed from consultees and members of the public. Regard will be had to any feedback received in finalising the outline TMP that will be submitted as part of the application for the TKES works.
1.4. Enforcement of final TMP 2. Triton Knoll Electrical System Project Description The onshore elements of the TKES works comprise the following: 2.1.1. Cable Route Up to 6 underground HVAC circuits will be laid from the landfall north of Anderby Creek, to the North of Skegness, Lincolnshire, to the National Grid substation at Bicker Fen, near Boston, Lincolnshire (approximately 60km). This route has been subject to a selection and refinement. Temporary Work Areas (TWAs) locations have been identified to allow easy access to and from the cable route. The locations of the TWAs have been chosen to minimise impact on local residents, businesses and the environment. The TWAs will be utilised to store and distribute materials required for each section of the cable route and for welfare facilities. There are a significant number of natural breaks in the cable route caused by major roads, railways, rivers and major drains hence a high number of TWAs are required. TWAs along the cable route are approximately 0.5 ha 1.5 ha. The cable corridor will be up to 60m wide. This includes space for: Fencing of the route; Cable circuit trenches; Temporary construction haul road; Temporary drainage; Separate storage of topsoil and subsoil (to retain integrity) on both outer edges of the corridor. The cables will be installed in plastic ducts laid in cable trenches. Jointing bays will be required approximately every 600m- 1,000m along the route to join lengths of cables. 2.1.2. Landfall TKOWFL has identified an area just north of Anderby Creek, Lincolnshire as the landfall area. The landfall area currently includes sections of two adjacent fields set either side of an existing privately owned raised access track. The exact location of the landfall infrastructure and associated TWA is subject to further detailed assessment, but will ultimately be sited entirely within just one of these fields. The existing access track from Roman Bank to the landfall site will be improved to allow access for construction vehicles. Up to six offshore transmission cables will come ashore at the landfall location at Anderby Creek. The offshore cables will be joined to the onshore transmission cables in underground Transition Joint Bays (TJBs). Horizontal Directional Drilling (HDD) will be utilised to install cable ducts for the cables under the sea defences to minimise disturbance, with the offshore cables pulled through the ducts to the TJBs. 2.1.3. Intermediate Electrical Compound An onshore Intermediate Electrical Compound is required approximately mid-way along the cable route, to provide system stability and improved efficiency of transmission. The location of this has been subject to consultation. The site includes space for the above ground infrastructure, drainage, landscaping, permanent and temporary access roads and a TWA. 2.1.4. Substation
A new onshore substation is required adjacent to the existing Bicker Fen substation. The location of this has been subject to consultation. The site includes space for the above ground infrastructure, drainage, landscaping, permanent and temporary access roads and a TWA. 2.2. Cable route construction and installation A number of methods will be used for construction and installation of the cables. Prior to construction a crossing schedule will be produced which will identify every crossing on the cable route and give the preferred crossing methodology. A detailed ditch survey will be carried out prior to construction. Method Statements will be produced for each crossing method used. A draft crossing schedule can be found in Volume 2, Annex 5.1 of the Triton Knoll Electrical System Preliminary Environmental Information. The following methods will principally be used for cable route construction and installation: 2.2.1. Open-cut trenching Open-cut trenching will be used to install the majority of the cable in relatively unconstrained areas. A trench will be excavated for each cable circuit, with ducts installed prior to the trench being back-filled. Cables will be pulled through the ducts from jointing pits. 2.2.2. Horizontal Directional Drilling (HDD) HDD will be used at the landfall to minimise impacts on sea defences and at crossings of railways, major drainage ditches and rivers as well as all public highways. The detailed methodology for each crossing will be determined following pre-construction surveys and consulted on with the relevant authorities. Table 2.1: Relevant Authorities for HDD sites Crossing Type Sea Defences Railways Watercourses Highways Relevant Authority Environment Agency Lincolnshire County Council Network Rail Environment Agency Internal Drainage Boards Lincolnshire County Council Highways Authority 2.2.3. Other Crossings Where HDD is not used for the crossings of private roads, drains, ditches and other obstacles, a pre-construction survey will be undertaken to determine the methodology to be used. Ditches may be flumed and cable ducts installed underneath the flumed ditch. Private roads may be open cut, with provision made for access where required.
2.3. Construction programme Construction periods for the various elements of the TKES are shown in Table 2-1.
Table 2-1 Triton Knoll Electrical System construction periods Triton Knoll Electrical System Component Landfall Onshore cable circuits Intermediate Electrical Compound Substation Pre-construction and Construction Work Up to 13.5 months of activity over a 36 month period Up to 42 months of activity over a 54 month period Up to 46 months of activity over a 54 month period Up to 65 months of activity over a 71 month period Works Included This covers all associated works including: Site investigation works, pre-construction archaeological and ecological surveys and mitigation; Site mobilisation including erection of fencing, and welfare and plant delivery; Earthworks and drainage works; Transition joint bay construction and HDD bores and duct installation Cable pulling, cable jointing and commissioning; and Demobilisation, including removal of temporary work area. This covers all associated works including: Site investigation works, pre-construction archaeological and ecological surveys and mitigation; Site mobilisation, fencing and welfare and plant delivery; Earthworks and drainage works; HDD, duct installation, cable pulling, joint bay construction, cable jointing and commissioning; and Demobilisation and landscaping. This covers all associated works including: Site investigation works, pre-construction archaeological and ecological surveys and mitigation; Site mobilisation, fencing and welfare and plant delivery; Earthworks and drainage works; Installation of electrical infrastructure, commissioning; and Demobilisation including site restoration. This covers all associated works including: Site investigation works, pre-construction archaeological and ecological surveys and mitigation; Site mobilisation, fencing and welfare and plant delivery; Earthworks and drainage works; Installation of electrical infrastructure, commissioning; and Demobilisation and landscaping. 3. General Principles 3.1. Pre and post construction surveys Prior to the start, and following completion, of the construction works, road condition surveys will be undertaken and agreed with the Highways Authority. These surveys will inform any works that may be required to rectify specific damage to the road network as a direct result of construction work
The pre-construction survey will be used to identify road surface irregularities which will require remediation to mitigate vibration impacts for the Noise and Vibration Management Scheme. 3.2. Monitoring As part of the ongoing process for ensuring that impacts due to the construction traffic are minimised, a monitoring strategy will be established between the TKWF and the relevant local authorities. Each contractor will be required to comply with the final TMP and the TK Environmental Clerk of Works will be required to monitor compliance and report breaches. In addition, a public hotline will be made available to members of the public. The hotline number will be published within the local newspaper for the area, so that the general public can voice their queries or complaints. 4. Construction Traffic 4.1. Construction access routes for HGV construction traffic The routes for HGV construction traffic to construction access points, incorporating any specific routes or locations to avoid and any temporary speed limit orders, will be agreed with the relevant Local Authority and set out in the final TMP. HGV traffic will use A roads wherever possible with B roads and minor roads used primarily to access the TWAs. Certain exclusions will apply in agreement with the highway authority in order to avoid congested or sensitive locations. This will include: Avoiding substation traffic passing through Boston; Using the A16 rather than the A52 around Skegness; and Using the IEC haul road to avoid Orby. All delivery contractors and construction staff will be instructed to use the agreed construction access routes, with compliance with the final TMP being a condition of supply contracts. A log of regular drivers will be maintained, including records of agreements with organisations and the drivers to demonstrate their understanding of the prescribed access route. 4.2. Construction access route signage Construction access routes will have temporary signs posted along the proposed routes, with the nature and placement of signage to be agreed with the relevant Local Authority or the Highways Authority. Signage will also be placed at the exit of construction site access points to instruct construction traffic to follow the designated route. TKOWFL will review the environmental performance of the main construction contractors as part of the tender selection process. 4.3. Site Access The site access points will be agreed with the relevant Local Authority and set out in the final TMP. The contractors appointed to undertake the TKES works will submit the detailed design and specifications for the site access locations to the relevant authorities prior to works commencing on site. All TWA s will have sufficient areas available at all times for all vehicles to enter in a forward gear and to be accepted directly.
4.4. Timing and phasing of construction traffic It is proposed that the permitted delivery hours are the same as the construction working times. Construction working hours are set as: Monday Sunday 0700 1900 Exceptions will be approved in writing by the relevant local authority. Phasing will be used to reduce peak daily vehicle movements by timing activities and deliveries to avoid cumulative effects for different parts of the TKES construction and where possible limit the cumulative effects with other developments. Community events and other factors will also be considered in the planning of major deliveries. 4.5. Abnormal loads The construction of the TKES will require the delivery of a number of abnormal loads. These deliveries will be small in number; each delivery will be planned in advance, escorted and managed such that any impacts are minimised. Such arrangements will be secured through the final Traffic Management Plan. 4.6. Pedestrian Management TKOWFL will maintain access for pedestrians wherever possible. Specific locations where pedestrian management will be required will be identified in the final TMP and where possible location specific management methods will be confirmed. 4.7. Temporary road closures and diversions TKOWFL has identified roads that may need to be temporarily closed and any diversions needed as a result of the TKES works. These will be identified in the development consent order submitted as part of the application following discussion with the relevant authorities. 4.8. Signage Any temporary signage required at access points and other works will be agreed with the relevant authority. 4.9. Contractors travel and parking The TMP will include provisions relating to contractors travel and parking. These provisions will be agreed with the Highways Authority to manage construction workers' traffic. The construction site will be in operation from 07:00 to 19:00. Construction workers will typically arrive before 07:00 and leave after 19:00. Therefore, personnel movements are typically limited to being outside of the traditional peak hours of 08:00-09:00 and 17:00-18:00. Provision for car parking for construction staff and visitors will be provided within the TWA and no car parking will take place on any other area outside of the site. Temporary car parking arrangements will be made at the start of the enabling works and following the creation of the TWAs, car parking will take place within a designated part of the TWA. Car parking will not be allowed on the site access road or any other areas that could cause delays for traffic turning into the site.
Figure 1.1: Site location of Triton Knoll Offshore Wind Farm.