British Columbia has released its first full provincial disaster and climate risk assessment since 1997. The Disaster and Climate Risk and Resilience Assessment identifies projected increases in climate driven hazards, including coastal flooding, wildfire, drought, extreme heat and earthquake risk, and states that significant infrastructure and land area will face rising exposure levels through the century.
According to the report, the average temperature in British Columbia has increased by 1.7 C since 1948. Winter temperatures have increased by more than 3 C, which the province notes is above global trends. Climate models used in the assessment indicate that B.C. should expect warmer winters, hotter summers, longer dry periods and more intense fall and winter precipitation in the years ahead.
The province modelled a 200 year coastal flood event under climate influenced conditions and found the total area of land at risk across B.C. will increase by about 200 square kilometres by the end of the century. That represents roughly a 25 per cent increase in coastal flood exposure.
Population exposure to coastal inundation is projected to rise from 5 per cent of the current population to 6 per cent by the end of the century. That shift represents an increase from about 220,000 people to nearly 280,000 people based on existing settlement patterns.
The report also identifies increased exposure for First Nations reserve infrastructure. Two per cent of built form on reserves, valued at $1.2 billion, is currently within areas exposed to coastal flooding. Under future conditions, that exposure increases to 3 per cent, valued at $2.3 billion.
Across all built parcels in the province, improvements valued at $33 billion are currently within coastal flood hazard zones. When projected future conditions are applied, that figure rises to $46 billion.
Provincial sea level projections identify Caswell Point on the west coast of Haida Gwaii as a reference site. Under high emissions scenarios, relative sea level at Caswell Point is projected to rise between 66 centimetres and 140 centimetres by the year 2100.
While Haida Gwaii is not named elsewhere in the report, the modelling shows a province wide trend of increased exposure for coastal and remote communities. Transportation infrastructure within projected flood zones expands significantly when future sea level and storm surge conditions are modelled. Railway exposure increases from 180 kilometres to 300 kilometres and unclassified road exposure increases from 1,500 kilometres to 2,000 kilometres.
The assessment also notes that remote communities and First Nations are expected to experience a greater rate of impact from coastal flooding when comparing projected future exposure to current exposure.
The Skeena and Bulkley region between Terrace and Prince George is identified as an active development corridor that contains key provincial infrastructure. Rail, road and energy systems in this region support northern resource projects and commercial routes to the Port of Prince Rupert.
Transportation impact scenarios in the report show increased risk to northern corridors during wildfire events. Road closures, poor visibility, single lane restrictions, debris flow and the loss of wooden bridge structures are identified as realistic impacts that can delay evacuation and restrict movement of goods. Rail operations may also be suspended during high hazard periods, which affects provincial logistics and supply chains.
The report references more than 35 damaging coastal flood events recorded in southern and northern B.C. and highlights a loss estimate of $1.5 billion from the 2007 Pacific Northwest storm system, described as the most significant coastal storm since the 1962 Columbus Day Windstorm.
The province states that the assessment is intended to guide adaptation planning. It also notes that future phases will include more region specific risk analysis. The document emphasizes that resilience building is achievable through forward planning, modernized infrastructure and decision making based on projected future conditions rather than historical climate patterns.
