ARISCC focuses on an integrated management of weather and climate related natural hazards in a way that keeps and improves railway infrastructure performance and avoids or minimizes damage to railway infrastructure assets. It starts with natural hazard management under today’s weather conditions and develops solutions and strategies to prepare for the changed climate and weather conditions of the future. ARISCC covers a wide range of weather and climate related natural hazards such as such as flooding, severe storms, landslides, rock fall, avalanches etc. and the respective risks for railway infrastructure. The results of ARISCC comprise the update and extension of an existing survey on the current status of adaptation of European railways to climate change, a guidance document on integrated natural hazard management, an extensive collection of good practices and two case studies using regional climate models for the identification of future regional climate loads and existing vulnerabilities of railway infrastructures.
The ARISCC guidance document for Railway Infrastructure Managers for an integrated natural hazard management comprises the following elements:
1. Weather Information and Weather Warning
2. Documentation & Assessment of past Weather Events
3. Natural Hazard Mapping
4. Monitoring and Documentation of the Status of Infrastructure Assets
5. Vulnerability Mapping
6. Risk Assessment and Risk Management
7. Regional Climate Models and Future Climate Loads
8. Adaptation Recommendations
For each of these eight elements, recommendations for the development and implementation of the respective systems and measures as well as good practice examples are given.
According to current climate models and projections, higher frequencies and intensities of extreme weather events are to be expected in the future. This holds with a certainty for very high temperatures, heat waves and intense short time as
well as extended rainfall events. Without an adaptation strategy and adaptive action, the present resilience of railways could proof to be insufficient in the near and midterm future. Therefore it is recommended to develop a proactive adaptation
strategy and systematically build up adaptive capacity. The strategy should comprise short term as well as mid-term and long term adaptation goals and measures and has to take into account affordability. The guiding principle of the integrated strategy
should be the three Rs
· Readiness - To be well prepared for extreme weather events
· Resilience - To systematically increase the resilience of the whole system
· Recovery - To have contingency plans allowing for fast and full recovery
Adaptation strategies should benefit the management of today’s extreme weather. This guarantees a strong direct link to every day operation of railway infrastructure and to the actual problems faced in connection with severe weather events and
impacts. Furthermore, it allows the exploitation of efficiency potentials through the concentration and focussing of resources which can be widely distributed over 5 different business units. At the same time, adaptive capacity is systematically built up. As a short to mid term option engineering specifications should be reviewed to pave the way for an improved resilience of the railway system. Changing specifications are most likely to be expected for the dimensioning of drainage systems, flood protection and for protection against heat waves. When measures are assessed and prioritised the objective should not solely be the strengthening of single assets or railway lines but the improvement of system resilience.
It is highly recommended to develop weather information and weather warning systems tailored to the needs of railway infrastructure operators. These systems allow a much more efficient disposition of resources, longer pre-warning times for severe weather events and so a higher awareness and better preparedness. Past extreme weather events and their impact on the railway infrastructure should be systematically documented and assessed as one important approach to identify the of the system. In parallel, the appropriate metrics for measuring the impacts should be developed. For easy access and convenient handling the data should be stored within a central “event database” and visualized by using a GIS. Systematic hazard mapping allows the identification of potentially dangerous situations for the railway infrastructure and the locations of potential impact. This provides an evidence base for identifying vulnerable assets. By using the output of climate models, hazard mapping can be extrapolated into the future and thus used for adaptation purposes.
A central asset database for all relevant kinds of railway infrastructure assets with detailed information about the current general and maintenance standard for each asset provides a solid basis for assessing vulnerabilities. In order to standardise and
simplify assessment procedures, different status classes reflecting the urgency of mitigation measures should be defined. Merging natural hazard maps with knowledge about past extreme weather events and the general status and maintenance standard of infrastructure assets allows the identification of the vulnerable parts of the railway system. The output of the merging process should be made available as vulnerability maps. These can provide a good basis for the selection of appropriate adaptation measures. A systematic risk assessment for weather and climate related events should be implemented taking into account possible impacts on railway infrastructure assets in five dimensions – safety, damage to assets, people, environment, reputation and financial losses. The assessment should be based on the above mentioned hazard and vulnerability maps and should integrate expert knowledge about expected frequencies of hazardous events. A convenient way to standardize the assessment process is the use of a risk matrix. Regional climate models should be used to identify expected future climate loads since they allow the calculation of possible impacts on the railway infrastructure. Relevant direct output of the models are trends for climate and weather parameters and – with less certainty - intensities and return periods for extreme weather events.
Recommendations for the Implementation of Adaptation Procedures
One of the core parts of an efficient natural hazard management system is a well structured and integrated database. This database can be gradually developed by interconnecting existing databases for asset management, maintenance planning 6
and disruptions as well as digitised railway network data. Provision can be made for missing elements such as event and incident databases which should be incorporated as available. For current operation, adaptation to climate change aspects should be integrated into current maintenance planning and especially priority setting timing decision procedures. Keeping good maintenance standards is already a first important step towards higher system resilience. For future projects, adaptation to climate change aspects should be integrated into the design of assets. This can be achieved by integrating adaptation into the early stages of current planning processes and especially into the standard vulnerability and risk analysis of project planning. Integration of adaptation aspects is highly
relevant for long living railway assets. There is a wide range of practical adaptation measures ranging from warning systems and monitoring to improving maintenance standards, reinforcement of protective structures and the change of standards for future projects. Priorisation of measures and finding the optimum combination for a project or a railway line depends on many factors such as types of assets, time horizon, importance of the route, financial constraints, cost benefit ratio etc. “Soft measures” such as real time monitoring of vulnerable sections and rapid alert systems can have much better cost benefit ratios than “hard engineering solutions” such as the reinforcement of protective structures. The implementation of an integrated natural hazard management starts a process of capacity building for the adaptation of the company to climate change. This process can be improved and accelerated by better knowledge exchange inside the company and between different infrastructure managers as well as with external stakeholders and partners. Good practices and pilot projects in the different areas should be openly communicated and actively shared. It makes also much sense to learn from those who are facing now the conditions you expect for your region in the future. The future role of UIC in strengthening and improving the adaptation of railway infrastructure to climate change could comprise the following measures and actions:
· Facilitate and coordinate knowledge sharing e.g. by hosting the ARISCC web
platform and by organising adaptation workshops
· Facilitate the development of appropriate metrics for impact and vulnerability
· Support the development of appropriate governance approaches for