The review of French standards for design, maintenance and operation of transport infrastructure was carried out by a technical working group set up by the DGITM involving experts of different transport infrastructures and systems: roads, bridges, earthworks, cableway, railway, aeronautic, waterway, maritime and port sectors. After summarizing major climate trends at short and long term, the working group screened existing French standards, in order to identify those that include references to key climate elements (such as "temperature", "flood", "rain", "wind"...) that could change in future. The screening, based on databases and expert opinions, mostly focused on technical documents; some regulatory and normative documents have also been taken into consideration. The selected standards were subsequently classified into three groups, in accordance with the needs for their revision from a climate change adaptation perspective:
- those with no need for revision: technical reference documents and corresponding standards that are not impacted by climate change;
- those needing revision: technical reference documents that are impacted by climate change and that already need to undergo a technical revision, and
- those needing more precise information of the climatic variables and indicators involved in order to determine whether they have to be revised, and how.
For the third group of standards, the existing information is not sufficient to assess whether there is a need to adapt them to future changes in climate, and further studies will be needed in future. Some examples of standards in each category follow:
- Standards with no need for revision: road traffic noise, road landscape design, road drainage guidelines, recommendations for structural design (limit states) in aquatic sites.
- Standards needing revision: road pavement design, estimate of general actions for aquatic structures (snow, wind, etc.).
- Standards needing further clarifications of the climate parameters: design and construction of new roads, maintenance of urban roads, draining road pavements, guidance on road embankments, principles to laying of long welded rails.
Some hundreds of technical standards (more than 800 only for roads) were revised. For those needing a more precise understanding of climate parameters involved (category (3) above), the transport experts have provided a list of the precisions required. These refer to the timing (when certain climate changes are likely to happen) and areas affected, or to the precise effects of those changes on some of the parameters used for infrastructure design (frequency of occurrence, intensity, number of days above certain levels, etc.).
Whereas the revision of standards within category (2) is already being undertaken, the revision of standards under category (3) can only proceed once the necessary clarifications have been provided by climate and meteorological experts. The revised standards will be adopted following the general procedure, including the participation of all relevant stakeholders, and subsequently implemented.