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Transport Scotland submission of 23 December 2021

PE1916/A - Request a public inquiry into the management of the rest and be thankful project

The Rest and Be Thankful is the highest point on the A83, separating Glen Kinglas from Glen Croe. It is also one of the places in Scotland with the highest risk of landslides and debris flow hazards. These have increased in recent years due to the frequency of heavy, intense and prolonged periods of rainfall.

Following a number of landslides across Scotland in 2004, Transport Scotland carried out a nationwide Scottish Road Network Landslides Study. As part of this study a hazard assessment and ranking exercise was carried out for debris flow. From this assessment the A83 Ardgartan to Rest and Be Thankful is one of the most highly ranked debris flow hazard sites in Scotland.

As part of the £87 million invested in the maintenance of the full length of the A83 since 2007, over £15 million has been invested in landslide mitigation works at the Rest and Be Thankful. This is helping keep Argyll and Bute open for business by reducing the impact of landslides on the A83.

The Scottish Government is aware of the A83's importance as the primary route into Argyll and Bute and in 2012 an A83 study was commissioned by Transport Scotland to identify and appraise potential options for the A83 trunk road to minimise the effects of road closure from landslides. The study included separate work to investigate the feasibility of removing pinch points and improve pedestrian safety in villages along the route.

The A83 Route Study was undertaken to identify and appraise potential options to minimise the effects of road closures with the objectives of:

• Reducing the impact on journey times by reducing the frequency and duration of road closures caused by landslides; and
• Reducing the economic impact to the A83 Study area by reducing the frequency and duration of road closures caused by landslides.

The final A83 Route Study and associated consultation feedback paper were published in February 2013, with the decision to progress with the Red Option which maintained the existing alignment of the A83 and included a range of landslide mitigation measures such as: additional debris flow barriers at locations where the landslide hazard is considered highest; improved hillside drainage adjacent to and under the road, and; introduction of vegetation and planting on the slope.

The Red Option was taken forward as it offered the best performance against the assessment criteria, providing a cost effective way of meeting the Study’s objectives (i.e. reducing the impact on journey times and the subsequent economic impact of a road closure due to landslide). Since the installation of the Red Option suite of mitigation measures over 2013 and 2014, it is estimated that these measures have helped keep the A83 open for at least 48 days when it would otherwise have closed.

This decision to proceed with the Red Option was discussed and agreed with the A83 Taskforce on 25 February 2013. The Taskforce was set up in 2012 with its purpose being to provide leadership and direction and ensure the delivery of the A83 Rest and Be Thankful emergency diversion route and subsequently a wider study into the permanent solution to landslides at this area. The Taskforce is chaired by the Minister for Transport and is made up of a large number of stakeholders including Transport Scotland, Argyll and Bute Council members and officials, Local freight haulage industry representative, Loch Lomond & the Trossachs National Park, chamber of commerce and the Timber Transport Group to name but a few.

The original study and associated documents can be found on Transport Scotland's website.

The decision to proceed with the Red Option, as detailed in the A83 Route Study, was based on the data and evidence available at the time. The following tables provide data with regards to the magnitude of landslides over the years as well as the data regarding the number of road closures of both the A83 Rest and Be Thankful (RaBT) and the Old Military Road (OMR) as a result of landslides. When both the A83 and the OMR are closed or in exceptional circumstances, where hillside conditions are deemed to pose significant risk the Strategic Incident Diversion Route (SIDR) via the A82 / A85 is used.

Annexes A & B (75KB, pdf) posted 14 January 2022

As noted in the information provided in the above tables the scale of the events which occurred in 2020 to 2021 were significantly larger than any of the previous events.

Following the landslide events which occurred between August 2020 and February 2021, a centre line barrier was installed along the A83 and then extended in spring 2021 to cover the areas most at risk. This barrier makes current single lane operation of A83 more resilient.

Additionally, a 175 metre long 6 metre high debris (HESCO) bund (earth-filled multi-cellular system manufactured from steel mesh and lined with geotextile) was installed in January 2021 improving the resilience of the Old Military Road.

A new catchpit was constructed and completed in 2021 and works on a further catchpit commenced in September 2021. These ongoing mitigation works are important as they improve the resilience of the road and make it quicker, easier and safer to open the road, should it be closed by a landslide.

It is worth noting that since the last landslides in February 2021 access to Argyll and Bute has remained open via the A83 or Old Military Road on all but 8 days.

Following the landslide events in August 2020, one of which was the largest recorded in the area, the then Cabinet Secretary for Transport, Infrastructure and Connectivity announced on 23 September 2020 that Transport Scotland would be taking forward the development and assessment work required to deliver a long term resilient infrastructure solution to the existing A83 in tandem with progressing substantial shorter term investment in the existing A83.

Eleven route corridor options were considered to address issues at the Rest and Be Thankful and develop long-term resilient access to Argyll and Bute. On 23 September 2020 the eleven route corridor options were published and we invited feedback on these options from stakeholders and the public via an online consultation launched on 23 September and running until 30 October 2020. Over 650 people provided feedback to the consultation. Please see announcement and plan of the eleven route corridor options.

Following completion of a preliminary assessment of all 11 route corridor options for improving access to Argyll and Bute and identifying a long term solution to the ongoing problems at the Rest and Be Thankful a preferred route corridor was announced on 18 March 2021.

The preferred route corridor was announced as the Glen Croe corridor. The preferred route corridor is more cost effective and quicker to deliver, having relatively less environmental constraints, although in absolute terms it remains technically challenging. On the same day a Preliminary Assessment Report was published providing a robust understanding of the existing conditions within each of the 11 route corridors options previously identified, and considerations on how feasible, affordable and publicly acceptable they would be to develop.

The announcement for the preferred route corridor in March 2021 also provided details of five possible route options within the preferred route corridor. These options range from traditional roads and localised structural protection, to full tunnel options. The range of engineering structures reflects the challenge of building resilience into the route.

Transport Scotland invited the public to provide feedback on five possible alternative route options within the preferred route corridor, including tunnel options, viaduct options and debris shelter options.

The purpose of this consultation was threefold:

• to provide feedback on the selection of the preferred route corridor;
• to seek feedback on the five possible route options presented, to fully understand the views of those who feel they may be impacted, how they are impacted and whether there are any environmental/cultural/heritage features which should be considered in future decision making with respect to the selection of a preferred route option within Glen Croe; and
• to understand if there were any other route options which members of the public felt should be considered within Glen Croe.

The information would help inform further assessment and design work. It is worth noting that this consultation exercise ran in parallel with the ongoing data gathering and design work on the project and in no way caused any delay to the ongoing work.

We received over 120 responses to this consultation, a report summarising the feedback can be found here.

In April 2021 a Strategic Environmental Assessment Environmental Report was published alongside the Preliminary Engineering Services Design Manual for Roads and Bridges (DMRB) Stage 1 Assessment. These reports follow on from the Preliminary Assessment and describes the more detailed assessment of the preferred route corridor as well as the five possible options which were published. These reports can be found using the links below:

As noted in the above Preliminary Assessment Report timescales for completion of a long term solution to the issues at the Rest and Be Thankful range from 7 – 10 years depending on the option.

These timescales allow for surveys and data gathering, design and assessment work, and as with other projects to improve the trunk road network, there will be a need to complete the necessary environmental assessments and statutory process to allow land to be acquired and the project constructed.

The assessment and design work is being undertaken in accordance with the Design Manual for Roads and Bridges which sets a UK-wide standard of good practice that has been developed principally for trunk roads and is accepted within the industry. The DMRB supports the implementation of the statutory process for all new roads as set out in the Roads (Scotland) Act 1984.

In recognition of the urgency to find a solution the announcement in March also confirmed Transport Scotland is progressing work to look at a medium term resilient route through Glen Croe to include consideration of the Forestry Track, improvements to the Old Military Road and other options on land already owned by Scottish Ministers. Depending on the statutory consents required, that work will seek to develop a finalised proposal by Autumn 2022.

Options being considered include providing a new diversion route on the south-western side of Glen Croe, examining whether the existing forestry track could be upgraded and making improvements to the Old Military Road to deliver a safer and more resilient diversion route for use if the A83 is closed.

Environmental, geotechnical, and topographic survey work has been underway since May 2021 to build our knowledge and understanding of the possible route options on the south-western sides of the valley and this work is ongoing.

We recognise that the timescales for developing an alternative to the current route and finding a long-term solution to the challenges created by the Rest and Be Thankful section of the A83 are frustrating for the local community. However, this scheme is technically challenging and the landscape is dynamic so it is vital we understand the terrain we are working in, in order to develop a suitable solution of the correct standard in the correct place. This is a data driven process.

At the same time, we remain committed to progressing substantial shorter term investment in the existing A83 in tandem with the work to identify a permanent solution. This work reduces the risk of road closures and improves the resilience of the route. While the catchpits and mitigation works cannot guarantee the road will not be closed due to a landslide, these important works make it safer, easier and quicker to clear the road and reopen to traffic.

Since the A83 Taskforce was set up in 2012, meetings have been held every 6 months and when that has not been possible written updates have been issued to the Taskforce. These meetings allow updates and discussion regarding the A83 Rest and Be Thankful and the ongoing works.

Since work began looking at a long term resilient solution, as well as a proportionate and resilient medium term solution, these items have been added to the Taskforce agenda for discussion. The most recent Taskforce meeting was held in September 2021. At that meeting the project team informed Taskforce members of the current position of the project, including all the information and assessments which are required. In addition, Transport Scotland committed to providing a substantial project update at the next Taskforce meeting in early 2022, as well as an open and transparent approach by sharing data, including results of surveys, ground investigation works etc.

In September 2020 Transport Scotland launched an Access to Argyll and Bute (A83) project specific webpage on the Transport Scotland website. A project specific Storymap website was also launched in March 2021 which provides information on the project as well as updates and ‘latest news’.

I hope this is of assistance.