Transportation Impact Assessment – Parsons (Jan 2026)
The TIA concludes that the 465-unit, 322-parking-space development will not materially impact surrounding intersections — but that conclusion depends heavily on mode share assumptions, older traffic counts, and modelling choices that exclude certain cumulative impacts.
Key Points
- Concludes that development will not materially impact surrounding intersections — but that conclusion depends on a 7% vehicle mode share assumption.
- All traffic counts pre-date the 2024 Scott Street reconfiguration (lane reduction + cycle track).
- The new Ottawa Hospital Civic Campus (opening ~2028) is not modelled, despite Parkdale being a primary access route.
- All 322 parking spaces route through a single Spencer Street access point — cumulative queuing with adjacent garage entrances is not modelled.
- No construction traffic plan, emergency corridor analysis, or road-widening easement impact analysis is included.
Full Analysis
What the TIA Covers
The report evaluates projected trip generation (vehicle, transit, pedestrian, and cycling), peak-hour intersection capacity, garage access operations, collision history at nearby intersections, and compliance with City TIA Guidelines. The study assumes occupancy in 2028.
Mode Share Assumption
The most consequential assumption in the report: only 7% of peak residential trips are assumed to be made by private vehicle. This is based on applying a Transit-Oriented Development (TOD) mode share, justified by proximity (within 600m walking distance) to Tunney’s Pasture LRT station. The report includes an alternative TRANS mode share scenario but does not use it as a sensitivity test. Because vehicle trip generation drives all intersection modelling results, this assumption materially affects the conclusions.
Traffic Count Data
Traffic counts used in the report are drawn from 2016, 2017, 2019, and early 2020 (COVID period). Scott Street was significantly reconfigured in 2024 — a four-lane road was reduced to two lanes with a cycle track added. All counts pre-date this change. The TIA acknowledges older counts were “balanced with adjacent newer traffic counts,” but does not include fresh counts reflecting post-2024 network conditions.
Background Growth Modelling
The TIA projects 2028 background conditions using historical growth rates (2008–2023) and identified area developments as of December 2024. The new Ottawa Hospital Civic Campus, scheduled to open around 2028 on Carling Avenue, is not explicitly modelled. Parkdale Avenue is a primary north-south route connecting to that campus. No cumulative hospital-related traffic analysis is included.
Spencer Street Garage Access
The proposal routes 322 underground parking spaces through a single ramp access and exit onto Spencer Street, a local residential street. The TIA characterizes Spencer Street as “a wide low volume local street.” Concerns raised by residents include:
- Winter conditions reducing Spencer to an effective single lane due to snow and on-street parking
- Cumulative interaction with two existing nearby garage entrances
- Queuing at the unsignalized Spencer/Parkdale intersection
- Move-in operations and garbage collection days adding further lane pressure
- No cumulative queuing model for all access points on the street
Emergency Corridor
The TIA identifies Parkdale Avenue as a north-south arterial and notes the Safety Trigger was met. However, the report contains no dedicated emergency vehicle corridor analysis, no documented consultation with Ottawa Paramedic Service, and no discussion of ambulance response implications.
Construction Period
The TIA does not include a construction traffic routing plan, excavation-phase vehicle volumes, heavy truck management, vibration monitoring for adjacent buildings, or a temporary traffic control plan. Given a four-level underground garage across a full city block, this omission is notable.
Road Widening / Easement
A two-metre road limit easement is noted as a requirement. The TIA does not analyze the resulting road geometry, sight triangle adjustments, interaction with garage access design, or implications for a future Transit Priority Corridor identified on Official Plan Schedule C2.
Why It Matters Here
The TIA’s conclusion that intersections will operate acceptably in 2028 rests on a 7% vehicle mode share, traffic counts collected before the 2024 street reconfiguration, background growth modelling that does not clearly include the new Civic Hospital, and no emergency, winter operations, or construction traffic analysis. Each of these is a legitimate basis for requesting supplementary information before the application advances.