Abstract Manager

Project costing is always a highly scrutinized element of the decision making process related to municipal infrastructure projects, particularly during periods of rapid inflation when the increasing costs no longer align with forecasted capital budgets, thereby impacting affordability. As part of the project costing activities related to the City of Ottawa’s update to the Transportation Master Plan (TMP), Parsons was asked to complete a comprehensive evaluation of a selection of updated roadway cost estimates that would provide stakeholders with an improved understanding of the factors contributing to the notable increases in project costs that have been observed in recent years, including through the period of the COVID-19 pandemic. Consideration was given to higher unit values due to inflation and market demands, changing/contemporary design standards, new Provincial/Municipal regulations, etc.  

The project involved an update of the existing Costing Model, originally developed by Arcadis/IBI to support the costing evaluation of the previous TMP update. This model is pivotal for estimating the costs of road projects, considering construction items, quantities for unique cross-sections, and unit costs. The approach included updating benchmark cross-sections to align with contemporary design standards.

As part of the updated Costing Model, the decision was made to base the unit rates on the City of Ottawa’s “Spec Code”, which monitors unit pricing information over time. This source reflects average unit pricing based on actual bid pricing for over 300 municipal road projects of varying size. With support from City staff, analyses were completed to assess the sensitivity of project scale and time window on the unit rates and resulting cost estimates.

The team also incorporated recent Provincial regulations on excess soil management, which significantly impacted unit rates for earth excavation. This regulation mandates stringent management and reporting of excess soils, adding considerable costs to projects with large excavation requirements. An adjustment was also made to the how property values were reflected within the Costing Model, which was essential to better reflect these costs particularly for projects involving significant property acquisition.

Our comprehensive evaluation provides a robust framework for estimating the costs of planned road projects in the City of Ottawa. By addressing practical challenges and identifying key costing trends, we aim to support the City of Ottawa in developing reasonable and indicative cost estimates for their planned transportation infrastructure projects. This presentation will offer valuable insights for transportation engineers and infrastructure managers facing similar challenges in their jurisdictions.