A Traffic Impact Analysis (TIA) assesses the adequacy of existing or future transportation infrastructure to accommodate additional trips generated by a proposed development, redevelopment, or land rezoning.

SOUTH FLORIDA
In South Florida, the methodology and thresholds to determine if a TIA is required vary from jurisdiction to jurisdiction. It is important to hire an experienced traffic engineer that is familiar with the requirements of each jurisdiction and understands what trip credits can be effectively applied to accurately project net new traffic generated by the project.
PALM BEACH COUNTY
In Palm Beach County the Traffic Performance Standards require an assessment to determine whether a significant amount of site traffic is projected onto the study area roadway links before determining whether a TIA is needed. This analysis is based on the proportion of site-generated trips to the roadway capacities in the study area.
BROWARD AND MIAMI-DADE COUNTY
For development projects in Broward and Miami-Dade County, it is based solely on the projected number of trips generated. Broward County follows the traffic study guidelines established by the municipality where the project is proposed. In the City of Fort Lauderdale, which is the largest municipality in Broward County, a traffic impact analysis is needed for developments projected to generate over 1,000 daily trips.
Instead of basing the need for a TIA on the number of daily trips, Miami-Dade County bases it on the number of peak-hour trips. There are three different levels of TIA which are divided between projects that generate less than 100 trips per hour (Level 1), 100-300 trips per hour (Level 2), and 300+ trips per hour (Level 3).

In a TIA analysis, credit is given for any existing development which already generates trips. There can also be credits for existing pass-by trips and internal capture for mixed-use developments.
Applying appropriate trip credits can help reduce the project impact of traffic in the area, which can reduce the need for improvements or the cost of impact fees. The TIA trip generation calculations are performed in accordance with the guidelines of the Institute of Transportation Engineers (ITE).
Do you have questions about how many multifamily units, homes, or how much commercial square footage will trigger a TIA? The experts at WGI can help!