Estimating the budgetary impacts of changing climate hazards on public infrastructure in Ontario

This report projects the budgetary impacts of extreme rainfall, extreme heat and freeze-thaw cycles on public infrastructure in Ontario. Much of Ontario’s public infrastructure was designed based on historical climate data, and the climate is changing, leaving the $708 billion portfolio vulnerable to climate hazards. In the absence of adaptation, more frequent and intense climate hazards are projected to add $4.1 billion per year on average over the century to the cost of maintaining existing public infrastructure in a medium emissions scenario. The additional climate-related costs of this “no adaptation” strategy represent a 16 per cent increase in infrastructure costs relative to a stable climate base case.

Adapting public infrastructure to withstand these climate hazards can help lower climate-related infrastructure costs. In a proactive adaptation strategy, where all public infrastructure is adapted over the next five decades, climate-related infrastructure costs would add an average of $3.0 billion per year over the century. In a reactive adaptation strategy, where public infrastructure is adapted more slowly at the end of their useful lives, climate-related costs would add $3.5 billion per year.