Drivers in northwest Utah County are finally getting some breathing room on their daily slogs between Lehi and Saratoga Springs. UDOT has opened two new travel lanes along Pioneer Crossing, so the corridor now carries three lanes in each direction. The widening wrapped up ahead of schedule, and crews are already pivoting to the next phase, when overnight work kicks in to set up the flex-lane control system.
What Changed On Pioneer Crossing
Instead of carving out a whole new roadway, crews squeezed more capacity out of what was already there. Shoulders and parts of the center median were converted to add one extra lane each way over roughly 4.5 miles of State Route 145. The result is a jump from two lanes in each direction to three in each direction.
According to UDOT, that reconfiguration is expected to keep up with peak-hour demand through about 2037. Engineers project more than six minutes of average daily commute time saved and sharper cuts in side-street delays once everything is fully in play.
Flex-Lane Equipment And Overnight Work
Now that the extra pavement is open, the late-night shift is about to get busy. Starting next Sunday night, UDOT plans overnight closures to install the overhead lighting and electronic signs needed for the flex-lane system, a schedule confirmed to KSL NewsRadio.
Those night operations are meant to keep daytime traffic moving while crews hang sign structures, run conduit and finish the wiring that will eventually control which lanes are open in which direction. In the same report, a UDOT spokesperson noted that parts of the roadway widening wrapped up about two months earlier than originally planned, which is why drivers are already seeing the added lanes.
How The Flex Lanes Will Operate
Once everything switches on, the flex lanes will not be a free-for-all. Overhead signals will govern which directions can use specific lanes. A green arrow will mark a lane that is open to traffic. A red X will mark a lane that is closed.
The concept is not new to Utah. A similar reversible-lane setup has been running on 5400 South in Taylorsville for more than a decade, as explained by Deseret News. The approach is designed to boost capacity in the busiest direction during rush hour without having to widen the entire corridor from scratch.
Local Impact And Timeline
Getting to this point has meant tearing into the heart of Pioneer Crossing. Crews have removed and rebuilt nearly 4.5 miles of roadway, taken out the wide center median and completed much of the drainage and pavement work on the north side. Those moves helped speed up the schedule, which is why drivers are seeing fresh pavement and additional lanes earlier than first advertised.
What is still left is mostly the finishing gear. Remaining tasks include new striping, signal work and the full buildout of the flex-lane control systems. Final activation of the reversible lanes is planned for later this year once the electronic signage is installed and testing is complete. The reconstruction milestone was detailed by the Lehi Free Press, and the early completion of parts of the widening was reported to KSL NewsRadio.
Background
The flex-lane concept for Pioneer Crossing was first rolled out in 2025 as a near-term way to tame rush-hour backups without waiting years for a larger rebuild. Local outlets have tracked the idea from early planning through construction. Hoodline followed the project launch and initial work last fall in its coverage of the planned traffic fix, and this latest round of work moves the corridor into its next, more operational phase.
For now, UDOT is asking drivers to keep an eye out for shifting lane patterns, respect temporary speed limits through the work zone and consider signing up for project email updates if they want weekly heads-ups on lane closures and timing. For more information and to join the mailing list, visit UDOT.
