PLUS 4011-10

1 INTRODUCTION TO THE GUIDELINE 1.1 Need for this Guideline Engineering projects in the North often encounter permafrost in their foundation environment. The ability of frozen ground to support these structures depends mostly on local climatic conditions, ground temperatures, soil/rock material properties, and ground ice conditions. Since significant climate warming is anticipated in northern Canada, community infrastructure in permafrost terrain should also be sited and foundations designed considering the potential for significantly different foundation environments in the future as permafrost warms and thaws. The analyses required to address permafrost and climate change-related factors will vary between projects, depending upon the type of infrastructure in question, its design, location, design life, and purpose. This Guideline supports the appropriate consideration of climate-change-related factors during the planning, design, and management of a range of community infrastructure in permafrost regions. In particular, it sets out to: 1. Provide an understanding of permafrost as an environmental variable, with a focus on how permafrost responds to climate and other environmental change; 2. Provide a general assessment of trends in climatic and permafrost conditions across northern Canada; 3. Describe the most common foundation types used for community infrastructure in permafrost environments; and 4. Outline a process for ensuring that the effects of climate change are incorporated, as appropriate, into the siting of community infrastructure projects and the design of their foundations. 1.2 Target audience This Guideline is for decision-makers with a role in planning, purchasing, developing, or operating community infrastructure in permafrost regions. It is meant to assist people who are generally not experts in either permafrost or climate change, by providing them with: 1. A better understanding of critical permafrost- and climate change-related issues; 2. A means for locating key information sources on these topics; and 3. An ability to ask “the right questions” of those they hire in order to carry out the planning, assessment, design, and construction of projects. 1.3 Limitations of this Guideline This Guideline relates to those structures that require foundations. As such, it will not be of direct relevance to all types of infrastructure in permafrost terrain. This Guideline is not meant to be a designer’s text book for foundations in permafrost, and it should not replace the expertise provided by geotechnical and other civil engineers, architects, planners, climatologists, and other environmental scientists who need to be engaged in all aspects of infrastructure planning, design, construction, and operation. While this Guideline focuses mainly on foundations and permafrost, it is critical to note that any infrastructure is best designed and operated as an integrated system comprising the infrastructure and the social and natural environment within which it operates. The guidance in this document should be used together with requirements and advice on structural design, heating systems, insulation, health and safety, and other aspects of infrastructure systems, so as to deliver assets that efficiently and effectively meet their intended purpose in the future. The National Building Code of Canada (IRC 2005) and the Good Building Practices Guide, published by the Government of the Northwest Territories (2009), are two important resources in this regard. The knowledge base concerning permafrost, community infrastructure and climate change, and mechanisms for minimizing risks stemming from the interaction of these factors, will undoubtedly improve in the future. Since this Guideline itself cannot be updated frequently enough to remain abreast of the latest developments in these rapidly evolving areas of knowledge, it instead makes reference to the websites of various “goto” organizations. There are a number of existing guides that address the issue of climate change adaptation. Users of the present Guideline might wish to consult, for example, “Adapting to Climate Change: A Risk-based Guide for Northern Communities” (Black et al., in press), and the “Infrastructure Climate Risk Protocol” (Engineers Canada, 2010).