OTHER RECOMMENDATIONS — LONG-TERM ISSUES
OTHER RECOMMENDATIONS — LONG-TERM ISSUES
There were 12 recommendations which related to issues to be addressed in the long-term. Eight of these issues related to temperature, rain, wind and coastal flooding; two related to winter conditions; and two related to severe weather events in general.
Design Issues
Recommendation 17 was identified to address the concern that the increase in temperature suggested by climate change predictions could result in changes to the basic design assumptions underlying particular design elements.
- Recommendation 17: Specify materials with appropriate stiffness to provide greater confidence that pavement deformation at high temperatures should not occur.
Action: It is considered that higher temperatures will generally be observed elsewhere in the UK in the first instance and that the approach in Scotland will draw on, and benefit from, this experience. Early implementation of Enrobé à Module Élevé (EME2 — pavement material with high resistance to deformation) has already been undertaken in Scotland.
Status: Progressing
Case Study: Trial of EME2 on the M876, near Kincardine Bridge
EME2 is a base/binder course material with a high content of hard paving-grade bitumen, smaller nominal size aggregate and a low air voids content. It is designed to combine good mechanical performance with impermeability and durability and high resistance to deformation. A trial of EME2 was carried out on a section of the M876 in 2005. The results of this trial continue to feed in to the assessment process, to determine the long-term suitability of this material for use in Scotland. To date, the performance of this material is encouraging.
Operational Issues
Recommendation 18 was identified to address the concern that the increase in temperature suggested by climate change predictions could result in effects which might not be identified unless a form of consolidated reporting is adopted.
- Recommendation 18: Consider periodic reviews of required pavement interventions to determine whether high temperatures have been identified as a significant contributing factor.
Action: Transport Scotland is implementing an Asset Management Improvement Programme, which will address this issue.
Status: Progressing
Operational Issues
Recommendation 19 was identified to address the concern that the increase in rainfall, combined with the changes in seasonal soil moisture condition, suggested by climate change predictions, could result in reductions in slope stability.
- Recommendation 19: Consider carrying out earthworks inspections under the principles of Technical Memorandum HD 41/03: Maintenance of Highway Geotechnical Assets pending further guidance on landslide risk management arising from the Scottish Road Network Landslides Study, prepared as a companion to this report.
Action: Insofar as HD 41/03 relates to earthworks generally within the curtilage of the road boundary, the Landslide Study does not specifically address the issue of inspection as set out in this document.
The requirements for earthworks inspections are addressed by the current term maintenance contracts. The maintenance contracts require annual inspections of embankments, cuttings and other geotechnical features. Areas of concern are monitored or investigated fully.
Status: Complete
Policy Issues
Recommendations 20 and 21 were identified to address the concern that the increase in rainfall suggested by climate change predictions could result in increased runoff leading to more and larger flood events occurring.
- Recommendation 20: Consider how enhanced communication could be developed with all parties involved in flood management.
Action: Initial discussions have taken place with SEPA in terms of enhancing communication in respect of flood warnings. Further discussions are required with emergency services to establish a communication protocol between the various parties, including local authorities, operating companies and other stakeholders.
Status: Progressing
- Recommendation 21: Consider how information on areas known to be at risk of flooding may be integrated with flood warning systems to provide early indication of potential hazards.
Action: Transport Scotland is developing a Geographical Information System (GIS) in the long-term, which it is intended will collate information relating to flooding that is readily accessible. Work is ongoing through the Asset Management Improvement Programme to identify areas at risk of flooding and to integrate this with other relevant information.
Status: Progressing
Operational Issues
Recommendations 22 and 23 were identified to address the concern that the increase in the incidence of high wind events suggested by climate change predictions could result in increased disruption to road users at exposed locations on the existing road network.
- Recommendation 22: Identify areas of the trunk road network that require full or partial closure in high winds and consider the introduction of wind barriers at these locations. This consideration should include a cost/benefit analysis and, if necessary, an environmental assessment.
Action: Transport Scotland has engaged the Met Office to undertake an analysis of wind speeds from 1971 onwards to identify sections of the trunk road network and major local authority roads which are most susceptible to high winds. Once issued, the High Winds Strategy will complete this action as one of its early stages of work.
Status: Pending
- Recommendation 23: Consider whether enhanced parking/turning facilities at locations on the trunk road network susceptible to full or partial closure in high winds would provide a cost-effective operational benefit.
Action: This action will be progressed following completion of Recommendation 22 and publication of the High Winds Strategy.
Status: Pending
Operational Issues
Recommendation 24 was identified to address the concern that coastal flooding could be exacerbated by a combination of climate change predictions for various weather types resulting in greater disruption on the existing trunk road network.
- Recommendation 24: Identify locations on the trunk road network susceptible to coastal flooding. This should take account of predicted sea-level changes and the possible effects of storm surges, to consider whether measures such as signage, sea-defences or re-routing are appropriate.
Action: Limited areas of the trunk road network are believed to be at risk but a formal review has not yet commenced, pending the issue of the next UKCIP datasets. These are now intended to be published in November 2008 following publication of an initial UKCIP report in December 2007, which described The climate of the United Kingdom and recent trends.
Status: Pending
Research Issues
Recommendation 25 was identified to address the concern that although snowfall is expected to reduce and temperatures increase, there is insufficient information available at present to consider how the current pattern of freeze/thaw cycles may vary in the future.
- Recommendation 25: Carry out further research on specific aspects of winter conditions where data does not presently exist, to provide a greater understanding of the likely pattern of change in winter conditions that is expected.
Action: No action is being taken on this recommendation at present, pending issue of the next UKCIP datasets. These are now intended to be published in November 2008 following publication of an initial UKCIP report in December 2007, which described The climate of the United Kingdom and recent trends.
Status: Pending
Policy Issues
Recommendation 26 was identified to address the concern that the predicted changes in winter conditions, once fully established, may be sufficiently significant to warrant a reconsideration of the strategic approach to winter maintenance.
- Recommendation 26: Consider the predicted changes in winter conditions to determine how winter maintenance of the trunk and local road networks may be carried out on a cost-effective basis.
Action: No action is being taken on this recommendation at present, pending the results of the research identified in recommendation 25.
Status: Pending
Policy Issues
Recommendations 27 and 28 were identified to address the concern that the general increase in severe weather events suggested by climate change predictions could result in a reduction in levels of service and safety for road users.
- Recommendation 27: Consider developing a road user education programme on the appropriate response to different types of severe weather events.
Action: Transport Scotland is considering adding information on appropriate responses to severe weather events to the Traffic Scotland website, which would build on the current severe weather warning information already present on the website.
Status: Progressing
Case Study: Winter Driving Information
Transport Scotland publishes advice on winter driving, which is now also available on the internet: www.transportscotland.gov.uk The purpose of this advice is to enable road users to travel safely by planning ahead; driving safely and remaining informed when travelling; and remaining safe in the event of being stranded. This form of road user education helps to prevent accidents during severe winter events. Real-time and future traffic information can be found at: www.trafficscotland.org
- Recommendation 28: Consider using the Variable Message Sign network operated by Traffic Scotland to support the above road user education programme.
Action: This recommendation is dependent upon completion of Recommendation 27 and the implementation of a road user education programme. No action has been taken at present, pending the results of Recommendation 27.
Status: Pending