Projects

City of Port St. Lucie:
Gatlin Boulevard Interchange IOAR and Design
Gatlin Boulevard and I-95 (SR 9) Interchange

St. Lucie County, Florida

American prepared and processed an interchange operational anaylsis report (IOAR) for the city to implement a two-phased improvement plan for the interchange. American conducted an interchange and signalization improvement study to assist the City of Port St. Lucie in determining how to improve the Gatlin Boulevard and I-95 (SR 9) interchange. Our engineers analyzed data, evaluating alternative design improvements using Synchro to test different recommended alternatives ranging from revision of signal timings, change phasing and adding lanes.

The pre-existing conditions of Gatlin Boulevard at I-95 consisted of having both the northbound and southbound off ramps operating under stop sign control. This condition resulted in severe delay and failure of the northbound and southbound off ramps. Failure of these ramps included vehicles queuing back to I-95, causing severe congestion of the overall interchange operation. Given these conditions, the City of Port St. Lucie received approval from the Florida Department of Transportation to place a temporary traffic signal at the southbound off-ramp intersection until permanent mast arm traffic signals could be installed at both intersections in phase one. After the installation of the temporary traffic signal, the first construction phase consisting of off ramp improvements in both directions and permanent signal installations were implemented that reduced delay time and queuing along the off ramps. The second phase consisting of

dual-left turns onto the interstate along with additional through lanes is currently under construction.

American was responsible for the planning, design, and construction services for these improvements including. This included responsibility for obtaining all Federal Highway Administration, Florida Department of Transportation and South Florida Water Management District approvals.