Interchanges are a point of transition for vehicles travelling between streets (where vulnerable road user safety is a primary concern) and freeways (where pedestrians and cyclists are generally not permitted). They usually feature multiple high-volume, high-speed turning, merging and diverging movements, and pose significant challenges to the safety and comfort of vulnerable road users including people with disabilities, pedestrians, cyclists and other active transportation users.
At a network level, interchanges represent the main opportunities for pedestrians and cyclist to travel across freeways. The combination of forced routing and safety/comfort obstacles mean that interchanges can represent a major barrier to walking and cycling in urban areas, and can negatively impact municipal objectives for increasing active transportation.
There is limited guidance available from TAC or other jurisdictions to help planners and designers provide safe and comfortable facilities for walking and cycling at interchanges.
OBJECTIVES
This project would:
- Provide descriptions of:
- The network-level impacts of freeway corridors on active transportation, and the importance of planning for freeway “permeability” for pedestrians and cyclists.
- The safety and operational impacts on active transportation users of all ages and abilities of conventional interchange designs (e.g. free-flow ramps with uncontrolled crossings, yield-to-vehicle conditions) and the resulting effects in terms of pedestrian and cyclist diversion.
- The interjurisdictional nature of many interchanges, and ways that different orders of government can work together.
- Document case studies of interchanges where:
- Active transportation desire lines are maintained for all ages and abilities.
- Conflict points are reduced or eliminated
- People walking and cycling experience a high level of comfort.
- Collaboration between different orders of government has achieved positive outcomes.
- Synthesize established or emerging Canadian and international practices for:
- Planning and network-level approaches to minimizing conflict points for active transportation at interchanges, including dedicated active transportation overpasses/underpasses and alternative interchange layouts.
- Design approaches to accommodating active transportation at interchanges, including both geometric design measures (e.g. ramp configurations, curb radii) and traffic control measures (e.g. signs, signals and markings), and the conditions under which each approach may be applicable.
- Identify and evaluate possible directions:
- Key opportunities and challenges facing the creation of urban interchanges that offer pedestrians and cyclists a level of safety and comfort equivalent to urban intersections, considering a range of factors including freeway operations.
- Key opportunities and challenges facing the retrofitting of existing interchanges using a systematic approach that recognizes site constraints and potential tradeoffs.
- Goals and principles for accommodating active transportation at interchanges in varying contexts (e.g. rural and urban; noting that urban contexts include both developed and future settlement areas).
The main project tasks would include:
- Review the international literature (both research and guidance).
- Survey key Canadian, American and international jurisdictions to identify approaches, methods, measured outcomes (e.g. impacts on collision rates and severity, pedestrian and cycling comfort and connectivity, and traffic conditions),and case studies.
- Synthesize current practice and guidance, identifying key themes and promising/proven measures.
- Identify gaps in current TAC guidance and conflicts between TAC and other guidance, and suggest opportunities to enhance TAC guidance.
The main deliverables would include:
- A comprehensive report documenting the literature review and survey, case studies, synthesis of practice, and possible directions.
- A technical memorandum for the attention of relevant TAC committees that identifies gaps and opportunities related to TAC guidance, and suggests possible further work.
