This paper discusses the challenges that were encountered by both Saskatchewan and Manitoba in developing life cycles for pavements that lead to the development of a Financial Sustainability Index for paved highway networks that is to be applied to highways in both provinces. The paper discusses the life cycle method used in the project and the sustainability index calculations. The intended use of the Financial Sustainability Index to support decision‐making is also discussed.
Initially the life cycle analysis was undertaken using performance and cost information from current Ministry pavement performance models. It rapidly became evident that those models are not sufficiently accurate to enable a proper life cycle to be undertaken. This led to revisions resulting in more consistent and rational models. Those models were then slightly modified again and form the basis for all of the life cycles performed during the second half of the project. The project uses whole of life costs that are annualized into an equivalent annual cash flow (EACF) per square metre of pavement. The annualized cost is then used to aggregate the whole of life costs for each network based on the proportion of the inventory that is within each condition state at the moment. Significant decisions about the long term levels of service underlie the life cycle costs (for the next 60 years).
As there are significant differences based on various assumptions both agencies are putting ffort into identifying benchmark life cycle profiles for each network class by condition state. Both Agencies intend to annually refine the benchmark profiles based on analysis of actual
performance.
Once both Agencies are able to accurately identify what the actual life cycles are then the sustainability index will be reported annually to accurately monitor funding levels for all classes of network for each year.
