ESB National Grid Kingscourt – Woodland 400kV Feasibility Study ESBI Report No. PE687-R142-002-001-001 Engineering, Design, Systems and Resources, ESBI Engineering and Facility Management Ltd Stephen Court 18/21 St Stephen’s Green Dublin 2 Ireland Telephone+353-1-703 8000 Fax+353-1-661 6600 www.esbi.ie DATE 02/12/09 File Reference: Falcon/DMS Client: ESB National Grid Project Title: Kingscourt – Woodland 400kV Report Title: Feasibility Study Report No.: PE687-R142-002-001-001 Rev. No.: 2 Volume 1 of 1 APPROVED: J.Doyle DATE: 02/12/09 TITLE: COPYRIGHT © ESB INTERNATIONAL LIMITED (1998) ALL RIGHTS RESERVED, NO PART OF THIS WORK MAY BE MODIFIED OR REPRODUCED OR COPIES IN ANY FORM OR BY ANY MEANS - GRAPHIC, ELECTRONIC OR MECHANICAL, INCLUDING PHOTOCOPYING, RECORDING, TAPING OR INFORMATION AND RETRIEVAL SYSTEM, OR USED FOR ANY PURPOSE OTHER THAN ITS DESIGNATED PURPOSE, WITHOUT THE WRITTEN PERMISSION OF ESB INTERNATIONAL LIMITED. Page i Summary ESB National Grid commissioned ESBI to carry out a feasibility study for a potential 400kV line linking the existing Woodland 400kV station in South County Meath to a proposed 400kV station in the vicinity south of Kingscourt in either counties Cavan or Meath. The new 400kV station would also be a termination point for a possible North – South 275/400kV interconnector This report details the options considered for potential overhead line route corridors between the above termination points. Potential route corridors developed during the desktop study were verified with an on-site investigation of driving the route options to check all road and river crossings and to note any potential conflicts with the desktop study. Route modifications and alternative options were investigated and are included in this report as a result of the information found during the site study. The overall route corridors linking Woodland to Kingscourt generally follow the shortest path but are bound by the major designated constraints particularly pertaining to County Meath and the expanding environs adjacent to Navan, Trim, Athboy and Kells. The potential route corridors were selected based on achieving a balance between environmental, technical and economic criteria. Site studies were also undertaken to assess potential sites suitable for a 400kV station in a study area south of Kingscourt. It found that a number of potential sites are available and these sites are evaluated under various headings. BGE gas pipelines were noted in the study area. It is recommended that a detailed study to determine the most effective mitigation measures be performed prior to design stage. The Woodland 400kV station has spare bay capacity to facilitate any proposed transmission line in the future but it may be more efficient to swap a new bay with an existing bay. The report concludes that overhead line route options currently exist and are technically feasible at the time of this study. However, crossing points are limited in some areas and projected population growth will continue to impact on route selection at road crossings. The report recommends that further detailed route investigation be undertaken to fully assess the route options in order to develop a preferred route. Page ii Contents Summary ................................................................................................................................. ii 1.0 Introduction..............................................................................................................- 1 - 2.0 Description of Study...............................................................................................- 1 - 3.0 Desktop Study.........................................................................................................- 2 - 4.0 Site Study ................................................................................................................- 3 - 4.1 Route Selection ..................................................................................................- 3 - 4.2 Constraints ..........................................................................................................- 4 - 4.2.1 Constraints Map .......................................................................................- 4 - 4.2.2 Landscape Character..............................................................................- 5 - 4.2.3 Existing Transmission Network...........................................................- 7 - 4.2.4 Roadways...................................................................................................- 7 - 4.2.5 Ribbon Development...............................................................................- 9 - 4.2.6 Towns and Villages ...............................................................................- 10 - 4.2.7 Ecological Sites and Special Designated Areas of Protection..- 10 - 4.2.8 Rivers ........................................................................................................- 13 - 4.2.9 Peatlands..................................................................................................- 15 - 4.2.10 BGE (Bord Gais) Infrastructure..........................................................- 15 - 4.2.11 Quarries, Mines and airstrips .............................................................- 16 - 4.2.12 Scenic and Tourist Roads ...................................................................- 16 - 4.3 Line Route Options ..........................................................................................- 16 - 4.3.1 Route descriptions ................................................................................- 16 - 4.3.2 General assumptions, caveats and conclusions ..........................- 22 - 4.4 Substations........................................................................................................- 25 - 4.4.1 Woodland 400kV station ......................................................................- 25 - 4.4.2 Proposed Kingscourt 400kV Station ................................................- 26 - 5.0 Consultation ..........................................................................................................- 29 - 6.0 Project Programme ..............................................................................................- 30 - 7.0 Conclusions and Recommendations ................................................................- 31 - Appendices Page iii 1.0 Introduction ESBI study focused on the potential for a 400kV single circuit feasibility study between the existing Woodland 400kV substation in Co. Meath to a proposed substation in the general vicinity south of Kingscourt in the counties of Meath or Cavan. 2.0 Description of Study The objective of the report is to assess the feasibility of obtaining an overhead 400kV line route between Woodland 400kV substation, Co. Meath and a potential 400kV substation in the vicinity south of Kingscourt. The outline scope of this study is based on ESBI Report PE687-R142-001-01-000: Constraints Study. The location of a 275kV inter- connector route from Northern Ireland will be a contributing factor in the final location of the proposed new station. Overhead line route will be selected based on achieving a fine balance between environmental, engineering and economic criteria. The study area covered an area of 67,000 hectares. The affected counties are Co. Meath and a small area of Co. Cavan (Kingscourt area). There are options of terminating in either Co. Meath or Co. Cavan which will be dependent on the site chosen for the proposed substation which is linked to the terminating point of the proposed 275kV inter- connector line from Northern Ireland. The Scope of Work is defined to include:- Constraints map Desktop study Field study Page - 1 - 3.0 Desktop Study Ref.: ESBI Report PE687-R142-001-001-000: Constraints Study The first task associated with the project was to define the study area. The area east of Navan was eliminated as any proposed development would have to cross the environmentally sensitive Boyne Valley. The area also has a high concentration of existing high voltage transmission lines including the Louth - Maynooth 220kV, Louth - Woodland 220kV and Drybridge - Finglas 110kV lines and the recently constructed Gorman 220kV station and the associated Navan-Platin and Navan- Drybridge 110kV lines which will be looped into Gorman station in mid 2005. In addition, it is proposed to link the Gorman station with 110kV developments to the existing stations at both Meath Hill and Navan. The study area chosen is situated in a north / south axis between Woodland 400kV substation in south Co. Meath and a proposed substation south of Kingscourt in the counties of Meath or Cavan. The area is bound to the east by the Hill of Tara and the town of Navan and to the west by the towns of Trim, Athboy. It is bordered to the north by the town of Kingscourt, Co. Cavan and to the south by Woodland Substation Co. Meath. The town of Kells and the villages of Nobber,Moyalty and Mullagh are included in the study area. A number of possible overhead line routes were identified and examined and a desktop study was produced which detailed the major physical and environmental constraints that might hinder a route corridor. Typical constraints included Ecological sites & Special Designated Protected areas, Archaeological & Heritage Sites, Scenic & Tourist Roads, along with all developments & infrastructure. Of particular significance were the Hill of Tara, The River Boyne and River Blackwater, two