In Florida, Traffic Impact Analyses (TIAs) are essential tools used to assess how proposed developments will affect the surrounding transportation infrastructure. The primary goal of a TIA is to evaluate the potential traffic operational problems or concerns that a new development might introduce and recommend appropriate actions to address such issues.  These analyses help ensure that new developments contribute to safe and efficient traffic flow, maintain acceptable levels of service, and identify necessary improvements to accommodate increased traffic demand. They are typically required for new developments depending on the size of the development and the amount of traffic projected.

Guidelines and Methodologies

The Florida Department of Transportation (FDOT) has developed comprehensive guidelines to standardize the preparation and review of TIAs. The “Multimodal Transportation Site Impact Handbook 2024” provides detailed procedures for evaluating the traffic-related impacts of development proposals. This handbook emphasizes a multimodal approach, considering not only vehicular traffic but also the needs of pedestrians, cyclists, and transit users.

Additionally, the “Traffic Analysis Handbook” and the “Project Traffic Forecasting Handbook” offer guidance on traffic analysis requirements and methodologies. These resources are intended for transportation practitioners who prepare or review traffic analyses for FDOT projects, ensuring consistency and thoroughness in evaluations.

Local governments within Florida often adopt their own TIA guidelines to address specific regional needs while aligning with state standards. The need for a traffic study is typically based on the amount of traffic generated.

While specific requirements vary by local jurisdiction, a TIA is typically mandated under the following conditions:

1. Development Size and Trip Generation:
   • If a project is expected to generate a certain number of peak-hour or daily trips, it usually triggers a TIA. Many jurisdictions set thresholds, such as 100 or more peak-hour trips or 1,000 daily trips, but the exact numbers depend on local regulations.
2. Land Use and Zoning Changes:
   • If a development requires a rezoning, land use amendment, or variance that could significantly impact traffic patterns, a TIA is often necessary.
3. Impact on Roadway Capacity:
   • If a development is projected to degrade the level of service (LOS) on adjacent roadways or intersections, a TIA is required to assess the impact and propose mitigation measures.
4. Proximity to Major Roadways or Intersections:
   • Developments near major highways, arterials, or congested intersections may require a TIA to evaluate potential traffic flow disruptions.
5. State or Local Requirements:
   • FDOT requires a TIA for developments that will affect state roadways. Local governments, counties, and transportation planning organizations may have additional TIA requirements tailored to their specific transportation networks.
6. Site-Specific Concerns:
   • If a project is expected to impact pedestrian, bicycle, or transit infrastructure, a TIA may be required to evaluate multimodal considerations.

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.

Conclusion

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).

Developers should 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 and can effectively and efficiently produce a traffic study, if necessary, that meet the guidelines of the jurisdiction(s).