Rethinking Urban Safety: Where is traffic most harmful?

The Traffic Hazard Tool maps and ranks traffic hazard across each street and intersection—helping cities act before tragedy strikes.

The Hidden Hazard

Traffic danger isn’t just about crashes—it’s about where people feel unsafe, where they avoid walking, and where poor street design threatens lives. The combination of traffic hazard (the level of potential harm) with exposure (the number of people using the space) is what results in different levels of crash severity. Developed through a robust Multi-Criteria Decision Aiding (MCDA) approach, the Traffic Hazard Tool provides a validated, data-driven way to measure and map traffic hazard across both street segments and intersections (example application in Montreal) in Montreal. This tool empowers planners, researchers, and the public to take a proactive approach to street safety with transparency and evidence rather than waiting for crashes before deciding /acknowledging that something is dangerous.

What Makes It Unique?

Built with Expert and Community Insight

Developed through consultation with transportation engineers, urban planners, public health professionals, parents, children and community members

Visual and Actionable

Hazard scores are mapped in an intuitive GIS platform, making results easy to interpret and use

Validated by Experts

Achieved over 90% alignment with expert rankings during the validation process.

Transparent and Reproducible

Built using a fully documented MCDA process. All criteria, weights, and decision logic are accessible and adaptable.

Comprehensive Data Inputs

Uses traffic and design characteristics , presence of heavy vehicle , Land use , Pedestrian visibility, and behavioral indicators.

Context-Ready

The tool is adaptable to other cities—just update the data and adjust weights if needed.

What Makes It Unique?

The Hidden Hazard

The Traffic Hazard Tool is a decision-support application that identifies, evaluates, and visualizes traffic danger at both street and intersection levels in urban areas. It is built through a two-part MCDA model using the MACBETH method, combining expert and community input with GIS spatial analysis to calculate hazard scores.

Who It’s For:

  • Community members
  • NGOs and advocacy groups
  • Researchers
  • Urban planners and engineers
  •  Policymakers

Methodology

Structuring

The Traffic Hazard Tool is based on a two-part MCDA framework:

Street Segment-Level Hazard Model:

Assesses street segments based on six criteria:

  • Traffic-design characteristics
  • Number of heavy vehicles
  • Traffic calming measures
  • Land use
  • Drivers’ visibility
  • Drivers’ behavior
Intersection-Level Hazard Model:

Evaluates different intersections using seven criteria:

  • Hazard level of connecting street segments
  • Geometric design of intersections
  • Traffic control
  • Pedestrian visibility
  • Traffic calming
  • Land use and Commercial size
  • Bike path design

Evaluation

  • Construction of performance level for each criteria
  • Weighting criteria

Validation

Each model was developed using the MACBETH MCDA method, with contributions from experts in transportation, public health, and urban design. Scores are validated and visualized through the GIS platform.

Explore the Maps

Interactive Hazard Map for selected neighborhood at City of Montreal

Adding Filter by hazard level, borough, or street type