Stromeferry Appraisal DMRB Stage 2 Report Volume 1- Engineering Assessment
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Stromeferry Appraisal DMRB Stage 2 Report Volume 1- Engineering Assessment October 2014 47065084/Doc/B/001 Final Draft Prepared for: The Highland Council UNITED KINGDOM & IRELAND The Highland Council Stromeferry Appraisal DMRB Stage 2 Report REVISION SCHEDULE Rev Date Details Prepared by Reviewed by Approved by June 2014 Draft Report Anke Menzinger David Taylor Project Commission Project Engineer Manager 01 July 2014 2nd Draft Report Jill Irving David Taylor Senior Engineer Commission Project Manager 02 July 2014 Final Draft Jill Irving David Taylor David Taylor Senior Engineer Commission Commission Project Project Manager Manager 03 Oct 2014 Final Draft Jill Irving David Taylor David Taylor Senior Engineer Commission Commission Project Project Manager Manager URS 6 Ardross Street Inverness IV3 5NN United Kingdom Telephone: +44(0)141 354 6050 Fax: +44(0)141 354 6059 STROMEFERRY APPRAISAL VOLUME 1 - DMRB STAGE 2 REPORT October 2014 - Rev 03 (Final Draft) 1 The Highland Council Stromeferry Appraisal DMRB Stage 2 Report Limitations URS Infrastructure & Environment UK Limited (“URS”) has prepared this Report for the sole use of The Highland Council (“Client”) in accordance with the Agreement under which our services were performed (refer to Client brief and Contract dated 10 th October 2012). No other warranty, expressed or implied, is made as to the professional advice included in this Report or any other services provided by URS. This Report is confidential and may not be disclosed by the Client nor relied upon by any other party without the prior and express written agreement of URS. The conclusions and recommendations contained in this Report are based upon information provided by others and upon the assumption that all relevant information has been provided by those parties from whom it has been requested and that such information is accurate. Information obtained by URS has not been independently verified by URS, unless otherwise stated in the Report. The methodology adopted and the sources of information used by URS in providing its services are outlined in this Report. The work described in this Report was undertaken between November 2012 and September 2014 and is based on the conditions encountered and the information available during the said period of time. The scope of this Report and the services are accordingly factually limited by these circumstances. Where assessments of works or costs identified in this Report are made, such assessments are based upon the information available at the time and where appropriate are subject to further investigations or information which may become available. URS disclaim any undertaking or obligation to advise any person of any change in any matter affecting the Report, which may come or be brought to URS’ attention after the date of the Report. Certain statements made in the Report that are not historical facts may constitute estimates, projections or other forward-looking statements and even though they are based on reasonable assumptions as of the date of the Report, such forward-looking statements by their nature involve risks and uncertainties that could cause actual results to differ materially from the results predicted. URS specifically does not guarantee or warrant any estimate or projections contained in this Report. Copyright © This Report is the copyright of URS Infrastructure & Environment UK Limited. Any unauthorised reproduction or usage by any person other than the addressee is strictly prohibited. STROMEFERRY APPRAISAL VOLUME 1 - DMRB STAGE 2 REPORT October 2014 - Rev 03 (Final Draft) 2 The Highland Council Stromeferry Appraisal DMRB Stage 2 Report REPORT SUMMARY S.1. INTRODUCTION In reaction to a rock fall event in December in December 2011, which closed the A890 over a period of several months, The Highland Council approved the proposal to carry out a further options appraisal in connection with Stromeferry Bypass. URS were appointed by The Highland Council to undertake an appraisal of route options for Stromeferry Bypass to satisfy the requirements of the Design Manual for Roads and Bridges (DMRB) Stage 2 Scheme Assessment. This is the non-technical executive summary of the report findings outlined in the ‘Stromeferry Appraisal, DMRB Stage 2 Report, Volume 1 – Engineering Assessment’. Reference drawings abstracted from Appendix A to the report are included at the end of this summary. S.2. STUDY AREA Stromeferry Bypass is an approximately 12km long section of public road along side the southern shore of Lochcarron, located in Wester Ross in Western Highlands in Scotland. The road forms part of the A890 between the Strathcarron Junction and the tie in with the A87, Invergarry to Kyle of Lochalsh Trunk Road. The road is mainly a single carriageway but reduces frequently to single track with passing places along this section of road. The existing Stromeferry bypass shares a narrow corridor with the single track Dingwall to Kyle of Lochalsh railway line along the southern shores of Loch Carron. This is particularly restricted over an approximately 4.5km long section from Ardnarff to Attadale, where the road / rail corridor is restricted by the Lochcarron shore to the west and the existing steep rock face to the east. The topography in the study area varies between sea level at Loch Carron up to levels of 490m above Ordinance Survey Datum along the range of hill south of Loch Carron. The existing A890 from the Kyle of Lochalsh to Loch Carron passes through undeveloped hill land and areas of forestry, experiencing steep road gradients of up to 14%. The land use within the area is agricultural, comprising mainline rough grazing in large of undeveloped heath and moorland, as well as areas of forestry and crofting. Other than the existing road network which includes the A890 Stromeferry Bypass, A896 and other local roads, other engineering constraints within the immediate study include: • Dingwall to Kyle of Lochalsh railway line, and the existing level crossing at Strathcarron; • Watercourses including Loch Carron and Strome Narrows, river Attadale, river Carron; • Settlements of Stromeferry, Slumbay, Lochcarron, Strathcarron, Achintee, Kirkton and other properties; and • Local steep topography, including the unstable rock face. Since the existing road was opened, the approximately 4.5km long section of mainly single track road from Ardnarff to Attadale has been subject to landslides and rock fall events, causing the Highland Council to temporarily close the road on several occasions, in order to enable remedial works to the rock slopes to take place. The closure of the A890 alongside Loch Carron results in diversions via the wider public road network of 130 miles length, through Achnasheen, Muir of Ord, Loch Ness side and Kintail. S.3. STAGE 1 SCHEME OBJECTIVES & CONSULTATIONS Stakeholder Workshops were held during the DMRB Stage 1 and 2 Scheme Assessment in accordance with the requirements of Scottish Transport Appraisal Guidelines (STAG). Stakeholders were initially divided into ‘Regulatory Stakeholders’ and ‘Economic Stakeholders’ for the initial workshops, with joint workshops held in the later stages. The STAG Pre-Appraisal, STROMEFERRY APPRAISAL VOLUME 1 - DMRB STAGE 2 REPORT October 2014 - Rev 03 (Final Draft) 3 The Highland Council Stromeferry Appraisal DMRB Stage 2 Report Part 1 & Part 2 process carried out for Stromeferry Bypass successfully delivered a set of Transport Planning Objectives to aid the appraisal of route options. A total of eleven scheme objectives were developed and are detailed below. • Deliver a safe and reliable, 2 lane carriageway by applying appropriate / proportionate design standards. • Minimise all risk during design, construction, operation and maintenance (with reference to risk register). • Ensure deliverability of scheme within programme and to agreed capital cost and maintenance budgets, thus providing ‘Value for Money’. • Solution reduces, or does not increase, the risk to and liability of the railway and maintains suitable access over the life of the scheme. • Deliver a scheme that assists both the local businesses to maximize opportunities for sustainable development and economic growth over the life of the scheme. • Safeguard and, where possible and appropriate, enhance and provide access to the natural and built environment and areas of national, regional and local importance and heritage, during construction, maintenance and operation of the scheme (with reference to environmental appraisal). • Scheme to take account of relevant local, regional and national planning policies (during the design stage). • Keep the A890 and peripheral road network open during construction. • Maintain and improve choice of transport mode and integration of public transport links over the lifetime of the scheme. • Maintain and improve local social cohesion by improving accessibility for emergency services responding to call-outs, as well as for the local and regional leisure, health and educational facilities. • Maximise / improve network efficiency, sustainable connectivity and social cohesion in terms of journey times and journey reliability in the Wester Ross area. In addition to Stakeholder workshops, Public Exhibitions were held during Stage 2 of the appraisal in order to provide information on the process and considerations in relation to the Stromeferry appraisal to the wider public. Stage 2 public exhibitions were held on 27 th March 2014 in Lochcarron Village Hall, and on 28 th March 2014 in Achmore Village Hall. Feedback from the