Abstract Manager

The paper outlines a comprehensive approach utilizing culvert inventory and condition data collected based on the AASHTO Culvert and Storm Drain System Inspection Guide (2020) to develop a condition, and climate-informed risk-based twenty-year capital works program for 2,200 culverts on Alaska Highway. The paper goes on to explain the methodology for establishing monetized life-cycle failure risks stemming from condition deterioration and extreme climate events. The life-cycle risk assessment is used to develop a culvert asset management system, which is used to produce a multi-year climate-informed capital works program.

In a previous study, a climate change vulnerability and risk assessment were completed on selected critical culverts on the highway using inventory and limited condition data collected 10 years earlier. As an outcome of this previous study, a comprehensive culvert inspection was carried out in 2022 based on the more robust data collection criteria outlined in the Culvert and Storm Drain System Inspection Manual (AASHTO, 2020). This 2020 AASHTO Inspection Manual, updates the inspection and rating criteria, incorporating over 30 years of changes since its original publication in 1986. The previous study's approach to assessing the risks posed by condition deterioration and climate change to 2,200 culverts along the Alaska Highway, British Columbia, was improved with more accurate culvert components-based predictive models to develop a capital works program to address those risks in terms of replacement, adaptation, and maintenance.

The adaptation and/or replacement options (strategies), were evaluated in a Life Cycle Cost Analysis (LCCA), by monetizing the costs and benefits of multiple strategies over a 60-year period. The economic analysis for climate change adaptation options quantifies the extent of cost and benefit of adaptation options under climate change scenarios. The costs considered in the LCCA include both "direct costs," directly incurred by the asset owners, and "user costs," which road users would incur through delays and detours. Overall, this approach should ensure that the culverts along the Alaska Highway can withstand the impacts of climate change and remain functional over the next 20 years.