SR 429 Widening & Systemwide Flex Lanes

CFX selected KCA to perform design services for the widening of SR 429 (Tilden Road to Florida’s Turnpike). This project is the southern component of an overall plan to widen SR 429 in three segments from Tilden Road to SR 414. This project provides additional capacity and increases the level of service (LOS) by adding an additional through lane with inside widening and constructing full-depth inside shoulders to serve as part-time shoulder use (PTSU) lanes — since branded as “Flex Lanes” by CFX. All mainline bridges (Stoneybrook West Parkway [South], CR 535, and Stoneybrook West Parkway [North]) were widened to accommodate an additional general use lane and Flex Lane in each direction, ramp modifications, and appropriate shoulder widths. An additional auxiliary lane was also added in both directions between CR 535 and the Florida’s Turnpike. The KCA Team was also responsible for the planning, analysis, and design of 35 miles of Flex Lanes on both SR 429 and SR 417. This system enables the inside shoulder to be dynamically opened during incidents or periods of high congestion, effectively providing incident management capabilities and on-demand capacity increases without the cost and disruption of an immediate eight-lane expansion. This Flex Lane system represents a first-of-its-kind technology application in the Southeastern United States road. The design incorporated Intelligent Transportation Systems (ITS) features including overhead lane control signals, dynamic message signs, variable speed limit display technology, closed-circuit cameras, and traffic speed and volume sensors. These elements are centrally managed through the Regional Traffic Management Center, allowing real-time decisions to open or close lanes, manage traffic during incidents, and communicate conditions directly to drivers. Additional work and SR 429 corridor improvements included milling and resurfacing of the existing lanes, drainage design and permitting, lighting, signing and pavement markings (S&PM), signalization, ITS (fiber optic network), temporary traffic control (TTC), utility design and coordination, surveying, and geotechnical analysis.  This project has been honored with the 2026 Florida Engineering Excellence Award (Grand Winner) by the American Council of Engineering Companies of Florida (ACEC-FL).