Antti Roose (Estonia) 1; Martin Ruul (Estonia) 2
1 - Tartu Regional Energy Agency; 2 - Hendrikson & Ko
A comprehensive climate change risk and resilience assessment has been undertaken to identify the potential risks of climate change on the Rail Baltica, a greenfield EU TEN-T railway infrastructure project to link Baltic states to the Central Europe railway network.
Risks of railways infrastructure assets are defined in probabilistic approach of their likelihood, based upon the long-term trends within the RCP4.5 and RCP8.5 of EURO-CORDEX ensemble. Assessment comprises the construction phase during 2019-2026, followed by maintenance and operations in the 100 year design life of the infrastructure and 50 years for systems. The climatic conditions in the Baltic Sea coastal-inland transition area here are characterized by high spatio-temporal variations (Rutgersson et al., 2014). Climate change amplifies the impact of adverse and extreme weather on the railway which have been insignificant so far. Importantly, the climatic knowledge is interpreted into a form that is relevant to railway sector, the sector-specific impacts of railways and their localization in the stage of hazard analysis.
The assessment has considered risks posed by climate related hazards such as storms, heavy rain and flooding, cold and hot weather to the assets associated with the Rail Baltica including tracks, overhead line equipment, stations and earthworks. Critical elements in assets are defined such as single points of failure either site-specific (point mode) or risk zone/corridors (vector mode) in the route or structure- and engineering-specific by assets and technologies. Assessment identified two medium risks posed by climate change: flooding and storms. Site specific flood and storm risk assessments and resulting design, construction, operations and maintenance measures proposed to avoid and minimize reduce the chance of the negative impact occurring. Problems with earthworks can arise as a result of milder winters.
Adaptation plan identifies high priority locations for resilience interventions, needs to upgrade standards, update asset policy and risk management plans as well re-consider variance in OPEX and the need for additional CAPEX. Design guidelines are to be upgraded against additional cost of preventive vs. corrective adaptation measures. Adaption at construction stage should provide resilience in the most cost effective manner in whole project life-cycle understanding the cost of different levels of resilience. However, the importance of climate risks could be exaggerated in current uncertainties which may lead to over-adaption and wasting resources, keeping in mind that the public follows the progress of the Rail Baltica project very closely and critically.