TAC Sponsor Spotlight Article — Artelia
Introduction: The Strategic Imperative of Prioritization
For transportation engineers and urban planners, it is an all-too-familiar scenario: a long list of technically justified projects, from new traffic signals to pedestrian safety upgrades, but a capital budget that can only address a fraction of them. In an environment of abundant needs and scarce resources, the critical question facing agencies is shifting from “Which projects qualify?” to “Which projects deliver the most value to our network, our community, and our long-term goals?”
Transportation planning is undergoing a major shift. Instead of looking at each project in isolation, today’s approach focuses on improving the entire transportation network as a whole. The mission of modern transportation agencies goes far beyond just moving cars quickly or cutting down on traffic delays.
Today, these agencies must navigate a complex balance of competing objectives, including enhancing safety, promoting equity, encouraging active transportation, and building environmental resilience. Traditional tools, developed for a simpler era, were not designed for this multi-faceted challenge.
Seeing the need for a better way to make important transportation decisions, the City of Laval, Quebec, partnered with the consulting firm Artelia Canada to elaborate a more robust, transparent, and defensible method for making these high-stakes investment decisions. The City sought to move beyond the simple pass/fail logic of conventional warrants and create a framework that could systematically prioritize projects based on a comprehensive understanding of risk, need, and strategic alignment for a specific case of prioritizing intersections for installation of signal infrastructure. Their work provides a practical model for how municipalities can make smarter, more equitable, and more effective use of limited public funds.
The Problem: Breaking Beyond Warrants
For decades, transportation agencies have relied on standardized warrant-based assessments, such as Quebec’s MTMD, Ontario’s OTM, or TAC and MUTCD guidelines, to justify traffic control installations. While these methods provide a rigorous, engineering-based foundation for determining if an intervention is technically needed, they often lead to a simple yes-or-no outcome. While these tools help identify which projects meet basic criteria, they don’t offer a built-in way to prioritize when there are more worthy projects than available funding. This limitation presents significant challenges. For instance, it offers no objective way to compare an intersection with high vehicle congestion against another with lower volumes but a history of collisions involving pedestrians near a school. Lacking a mechanism to weigh these complex trade-offs between measurable volumes and qualitative factors like community risk or equity, decision-making can become less structured. Furthermore, a reliance on historical data, particularly crash history and vehicle volumes, creates a reactive loop, inherently prioritizing locations that are already demonstrating failure. A modern framework should also enable a proactive approach, identifying and mitigating risk before a pattern of incidents emerges. The challenge with legacy tools is not just their inability to rank; it is their inherent bias toward past events, which is not always aligned with the preventative philosophy of modern safety programs.The Solution: A Dynamic Framework for Modern Decisions
To move beyond this binary limitation, the Artelia Canada team developed a solution grounded in Multi-Criteria Analysis (MCA), a structured methodology for making complex decisions. At its core, MCA functions like a detailed, customized scorecard for each potential project. The engine driving this scorecard is the Analytic Hierarchy Process (AHP), a technique that translates an organization’s strategic priorities into numerical weights for each category on the scorecard. Through a systematic process of pairwise comparisons, experts determine the relative importance of each criterion, ensuring the final ranking directly reflects the city’s unique goals. For the Laval project, this resulted in a holistic scorecard built on four main criteria:- Road Safety: A composite measure that looked beyond historical crash data to include proactive assessments of on-site risks (like poor visibility or complex geometry) and the proximity of an intersection to vulnerable land uses such as schools, hospitals, and senior residences.
- Pedestrian and Cyclist Traffic: An evaluation of active transportation volumes, giving explicit weight to the needs of vulnerable road users, a factor often underrepresented in vehicle-centric models.
- Vehicular Volume: An assessment based on established provincial warrants, ensuring regulatory compliance while placing vehicle flow in context with other priorities.
- Network Coherence: A measure of how a new signal would integrate with the surrounding network, promoting coordinated traffic flow and preventing the creation of isolated, inefficient signals.
- Centralized Data Hub: Microsoft SharePoint and Lists were used to create a structured, centralized database for all 106 candidate intersections, replacing scattered spreadsheets to ensure data integrity and accessibility.
- Systematic Expert Input: The AHP weighting process was streamlined using tools like Microsoft Forms. This allowed for the efficient and recordable collection of expert judgments, making the process transparent and repeatable.
- Geospatial Intelligence: The integration of ArcGIS web services and QGIS was a critical step. This transformed the list of intersections into an intelligent, interactive map, enabling powerful spatial analysis such as calculating proximity to parks or identifying clusters of high-risk locations, and providing compelling visualizations, like the project’s final heatmap of priority sites.
Putting It into Practice: How Laval Is Leading Smarter Transportation Decisions
The application of this framework to 106 intersections across Laval provided immediate and powerful insights. The process successfully translated the city’s strategic focus on safety and active transportation into a clear, data-driven ranking, creating a defensible roadmap for phased investment. A significant finding was the framework’s ability to uncover hidden risks. The holistic scorecard identified several intersections as top priorities for intervention even though they did not meet traditional volume-based warrants. For instance, one highly ranked location, despite having relatively low traffic, exhibited a history of collisions and issues like poor visibility. Situated in a complex urban environment, it was a clear risk that a conventional, volume-centric analysis would have overlooked. This demonstrates the framework’s power to move beyond simple congestion metrics and identify locations that are more critical in their current state.To ensure the final recommendations were robust, the Artelia Canada team conducted a sensitivity analysis, modeling how the rankings would change under different policy priorities, such as a “Safety First” model versus one focused on “Fluidity.” The intersections that consistently ranked high across multiple scenarios formed the basis of the final recommendations, providing the city with a highly defensible and resilient investment plan.
Ultimately, the framework developed for Laval offers a replicable model for any municipality seeking to optimize its capital spending. By moving beyond the limitations of traditional warrants, this approach enables transportation agencies to make more informed, equitable, and transparent decisions. It ensures that limited resources are directed to the intersections with the most critical need, creating a safer, smarter, and more cohesive network for all road users.
