Transportation Impact Assessment (TIA) Guidelines – 2023 Revisions
TL;DR
The 2023 TIA Guideline revisions streamline and simplify how transportation impact assessments are scoped and prepared, update trip generation triggers, and clarify study requirements — all to align with provincial planning changes and City priorities while maintaining a focus on sustainable modes, TDM, and efficient analysis.
Key Points
- TIA required if a development generates 60+ person trips per hour (not just vehicle trips).
- TDM analysis required for all developments generating more than 60 person trips.
- Transit capacity triggers at >75 transit trips; intersection design triggered at >75 auto trips.
- Protected Major Transit Station Areas (PMTSAs) explicitly added as a location trigger.
- Parking justification module added — applicants must justify deviations from zoning standards.
- Spillover parking analysis removed.
- Revised Guidelines in effect as of June 14, 2023.
Full Analysis
Why These Revisions Were Made
- Revisions were driven by Ontario’s Bill 109 (More Homes for Everyone Act, 2022), which seeks to speed up development approvals.
- The goal is to streamline TIA requirements for applicants and City staff while preserving effective transportation analysis.
Changes to the Guideline Structure & Process
Streamlined Steps
- Step 3 (Forecasting) was removed; forecasting work was moved into Steps 2 and 4 to reduce redundant reporting.
- One interim check-in with the City was removed to make the process more efficient.
Scope Based on Actual Impacts
- Site-generated demand and background network travel forecasting are now handled in ways that better tie triggers to actual trip impacts, including modal share considerations (e.g., transit use).
Updated TIA Triggers
Trip Generation Triggers Adjusted
- A development must prepare a TIA if it generates 60 person trips per hour or more, rather than only measuring vehicle trips.
Location Triggers Expanded
- Protected Major Transit Station Areas (PMTSAs) are now explicitly included as triggers that can necessitate a TIA.
Auto Trip & Transit Triggers
- Transit route capacity considerations are triggered if a site generates more than 75 transit trips.
- Intersection design and transit priority requirements are triggered at more than 75 auto trips.
Site Design & TDM Considerations
Transportation Demand Management (TDM)
- A TDM analysis is required for all developments generating more than 60 person trips.
- The Guidelines explicitly include TDM tools such as transit passes, cycling improvements, and car-sharing support as part of the assessment.
Parking Justification
- The revisions include a parking analysis module that asks applicants to justify changes to zoning by-law parking requirements rather than assuming supply by default.
Adjustments to Network & Access Modules
- Spillover parking analysis was removed, as it was determined to have low impact.
- Access location, control, and design details were combined and shifted into the intersection design module to focus on network operational impacts.
Implementation & Next Steps
- The revised Guidelines took effect June 14, 2023 and apply to all new Site Plan, Zoning By-law Amendment, and Official Plan Amendment applications after that date.
- A new TDM tool to support the revised TIA process was expected to be released in Summer 2023.
- A comprehensive review of the full TIA Guidelines was anticipated to be completed by 2024.