District of North Vancouver Adopts Policy on Risk Tolerance Criteria
The District of North Vancouver recently endorsed a policy on risk tolerance criteria for natural hazards. The policy sets the maximum levels of tolerable risks to life for both existing and new developments within the community. The risk tolerance criteria is based on research, public input, dialogue with subject-matter experts, the experience of other jurisdictions, natural hazard situations and the District’s own experience applying interim risk tolerance criteria.
The criteria are expressed both quantitatively and as the minimum factor-of-safety of a slope. Hazard and risk can be assessed using a variety of methodologies; however the method of assessment is determined by the Qualified Professional and the decision is based on which approach is most appropriate for the site conditions. In addition to meeting the risk tolerance criteria, risks should be further reduced to as low as reasonably practicable.
Risk tolerance criteria have been utilized by the District, on an interim basis, to manage landslide risk since early 2005. The Risk tolerance criteria policy sets clear requirements for applicants for subdivisions, development approvals and buildings permits in terms of landslide and debris flow risk management. As other standards such as the building code change, or as socioeconomic or community values change, the District anticipates that the criteria will need to be reviewed and revised.
More information is available on the District of North Vancouver website: www.dnv.org/hazards.