Further reading
The key external documentation for transport-specific thresholds falls into five groups.
Risk assessments
The National Highways and Network Rail Climate Change Risk Assessments are the starting point for the whole approach. They identify the receptors and risks that warrant threshold investigation, and their risk codes are carried through into the output database.
Industry standards
| Mode | Documents |
|---|---|
| Road | Design Manual for Roads and Bridges (DMRB); Manual of Contract Documents for Highway Works (MCHW) |
| Rail | Rail Safety and Standards Board (RSSB) documentation; Catalogue of Network Rail Standards |
These define current design, construction and operational parameters, and are the principal source of design thresholds.
Policy and industry documents
- Fourth Round Adaptation Reporting Power (ARP4) reports from National Highways and Network Rail
- National Highways, Climate Change and the Strategic Road Network: Building resilience for a changing future
These tend to be the source of operational thresholds, since they describe what organisations actually do in response to conditions.
Published research
Relevant Transport Research Laboratory (TRL) studies. Research sources are particularly useful where an impact depends on several interacting variables and a formula is more appropriate than a single value.
Climate projections
UKCP18 climate projections, used for assessing future threshold exceedance. See climate scenarios for how the same projections are used elsewhere in the IMP.
Standards underpinning the CCRA method
The sector-wide CCRA approach was developed in collaboration with Defra and aligned with international standards for climate adaptation and risk assessment (ISO, 2019; ISO, 2021).