Saskatchewan Ministry of Highways and Infrastructure has been working to develop a preservation policy that will be integrated with broad provincial goals and objectives, and that can strategically guide and explain the investment on highway preservation. Saskatchewan has a large provincial highway network. It is commonly understood that not all highways have the same level of importance in supporting economic and social activities. It is necessary to establish preservation priorities to provide a safe and efficient highway system using limited resources. A proper highway hierarchy for preservation will ensure that important highways are preserved to an appropriate level under limited funding and the province gets value for the money invested in preservation. Principles and applications of highway hierarchy system have been reviewed. It is found that highways are often classified into different hierarchical systems for different purposes. Although all transportation agencies have a highway functional classification system, it is often not used directly for priority setting of highway preservation program and network performance measurement. This paper describes a study to develop the highway hierarchy for preservation (HHP) in Saskatchewan. Principles of the hierarchy development were established and they include that the hierarchy shall be determined mainly by highway functions and facility utilization rate. A range of specific criteria are used to generate HHP options. Extensive evaluation on network traffic, inventory, current services, and pros and cons for each option were conducted. The chosen HHP has modified existing functional classification system by incorporating traffic thresholds, considering single access and auxiliary lanes, and current preservation practices etc. The HHP is used in the development of level of preservation services for provincial highways.
