Introduction and background 1.1 Context 1.2 Original Scheme 1.3 Road Accident Reduction Plan 1.4 Scottish Transport Appraisal Guidance Report 1.5 Ministers Announcement 1.6 Re-start Workshop 1.7 Revised Scheme Objectives 1.8 Appraisal Process 1.9 Layout of Report
Introduction and background
Guidance on the reporting of studies for trunk road improvement schemes is provided within the Design Manual for Roads and Bridges (DMRB). Advice note TA37/93 "Scheme Assessment Reporting" included in Volume 5 of the DMRB sets out a three stage process for reporting such studies:
- Stage 1 – Preliminary Assessment
- Stage 2 – Route Options
- Stage 3 – Preferred Route
In 1995 a Stage 2 report was produced for the dualling of the A90 between Balmedie and Tipperty that followed the DMRB guidance. This document now provides an addendum to the Stage 2 report by updating the original baseline information for the study area and describes the appraisal of new sub-options which have been considered during 2005 and 2006. The factors taken into account are identified, in particular the environmental, engineering, economic and traffic advantages and disadvantages of each sub-option. The report concludes by setting out the consultants’ recommendation for preferred route.
Upgrading the existing road to dual carriageway standard was the subject of an original commission undertaken by JMP Consultants in the 1980s.
In June 1994 Carl Bro was commissioned to undertake a Stage 2 Route Options Assessment. The study options included an evaluation of the original JMP route together with off-line alternatives that were examined for their engineering and environmental merits. This work was recorded in the Stage 2 Report 19951. Carl Bro went on to prepare draft Orders for a preferred route that was published in 1996 together with a Stage 3 environmental assessment that was produced by their sub-consultants, Turnbull Jeffrey Partnership. Further to the publication of the draft Orders objections were received from affected landowners and tenants. These related to intrusion, noise, visual impact, loss of and severance to land and increased journey times for those requiring local access.
Following the moratorium on preparation of major trunk road schemes in 1997, the scheme was considered in the Scottish Strategic Roads Review. In November 1999 the Scottish Executive published the results of the review which contained the decision that the A90 Balmedie to Tipperty scheme was to be held in abeyance and considered alongside other emerging priorities for a future trunk road programme which would be appraised using a multi-modal approach.
Since 1996 the Scottish Executive has implemented a number of measures that have improved road safety along the route as part of a route accident reduction plan. Works undertaken include:
- Improved and increased signage throughout the length of single carriageway;
- Speed restrictions through Foveran village;
- Verge markers and white minor access markers;
- Improved road markings e.g. ghost islanding, increased edge of carriageway markings, double white lining;
- Street lighting from Balmedie to the Menie/Delfrigs area; and
- Anti-skid surfacing at Balmedie.
In addition to the above measures it is also planned for further speed restrictions through Foveran village. A 20mph speed restriction will be enforced throughout school hours in the near future.
In 2004 Carl Bro produced a Scottish Transport Appraisal Guidance (STAG) Report that assessed transport problems associated with the users of the A90 corridor between Balmedie and Tipperty and appraised options for transport improvements to address current and emerging transport problems. Environmental input to the STAG appraisal was produced by Natural Capital. The appraisal was objective led and a key problem being that platoons of traffic regularly form along the section behind slow moving vehicles. The options for improvement were evaluated against overcoming the identified problems.
In June 2005, following consideration of the STAG report, the Minister of Transport announced that the offline dual carriageway option with grade separated junctions should be progressed to design stage. This decision was broadly welcomed, in particular by the regional transport agency NESTRANS. The estimated scheme cost for this option was reported to be in the range of £35m to £40m.
Following the Minister’s decision a re-start workshop2 was organised between representatives of the Scottish Executive and the Carl Bro design team that included Natural Capital. The workshop was facilitated by Capital Value and Risk Management Group. The purpose of the workshop was to bring together the key parties and to jointly review the previous scheme objectives and preferred scheme (including junction arrangements) in line with current design standards, environmental constraints and legislation, together with comments received following the publication of the previous draft Orders. The workshop attendees identified that several "route sub-options" should be developed and further investigated.
As part of the re-start workshop a review of the original scheme objectives was undertaken. The updated objectives reflect both current Government transport objectives and also those generated by the STAG evaluation process. The revised scheme objectives are as follows:
- To improve strategic and local accessibility on the A90 corridor between Balmedie and Tipperty for all types of road users.
- To improve the movement of traffic on the A90 between Balmedie and Tipperty in order to aid economic prosperity and development in the north east of Scotland.
- To improve road safety on the A90 between Balmedie and Tipperty.
- To minimise intrusion of the new works on the natural environment, cultural heritage and to enhance the local environment where opportunities arise.
- To facilitate integration along the A90 corridor by providing opportunities for more reliable public transport.
The route sub-options identified at the re-start workshop have been subject to an extensive evaluation process as shown in the flowchart below.
The process has involved stakeholder consultation throughout, including a Route Options Public Exhibition held in Balmedie over a two day period in June 2006. The exhibition allowed interested parties (including MPs, MSPs, councillors, landowners and users of the route) to view the sub-options and give comment on the layouts displayed. Further details are contained in the Exhibition Report, August 2006 and in Section 3.3. The process also involved reporting back to the workshop group on initial appraisals of the route sub-options. Workshop No. 2 also explored junction strategy options using framework comparisons to determine the main factors to be considered in developing the proposed junction layouts.
The remainder of this report is set out as follows:
- Existing conditions are described in Chapter 2;
- The route sub-options and junction strategy are introduced in Chapter 3;
- Engineering, Environmental and Traffic & Economic assessments are presented in Chapters 4, 5, and 6 respectively;
- Chapter 7 draws together the findings of the appraisal and sets out the consultants’ recommendation for the preferred route.
The report is supported by the following appendices: