What is a traffic report?
A traffic report, also known as a traffic impact analysis (TIA), is a study of the potential traffic impacts of a development on the surrounding transportation system. The purpose of the study is to document the impacts and recommend on-site and off-site mitigation for those impacts.
When is a traffic report required?
A traffic report is required for any new development, re-development or change of use (including tenant improvements).
Who does the traffic report?
The applicant will hire a consultant to provide the traffic report. The consultant must be a professional engineer, licensed in the State of Washington.
What is included in a traffic report?
There are two types of traffic reports:
Level-One Traffic Report
Level-One Traffic Reports are required for all new development, re-development or change of use projects. Some of the items to be included in the report are:
- Project Narrative
- Existing and Proposed Use
- Existing and Proposed Access Design
- Existing Traffic Standard Nonconformities
- Trip Generation Data
- Proposed Project Trips
- Net New Trips
- Sight Distance for Vehicles and Pedestrians
- Other Information, as needed
Level-Two Traffic Report
Level-Two Traffic Reports are required for larger, more complex projects. Some of the items to be included in the report are:
- All Level-One Traffic Report Requirements as noted above
- Vicinity Map
- Discussion of internal circulation; may include a queuing analysis and loading plan with turning exhibits
- Trip Distribution
- Level of Service
- Discussion of pedestrian, bicycle, and transit facilities
- Accident Report Data
- On-site and Off-site Mitigation
- Traffic Management Program