Officials Launching $24.6M North Austin Road Work

AUSTIN, TX — Texas Department of Transportation officials have scheduled a Wednesday groundbreaking for a $24.6 million road project in North Austin that features a diverging diamond feature.

The project is designed to reconstruct the area around Interstate 35 at Parmer Lane and Parmer Lane at Lamar Boulevard intersections. Among the project's main elements:

• The Mobility35 project will include an innovative diverging diamond intersection over I-35 to alleviate existing bottlenecks at Parmer Lane.
• Widening and extension of the northbound frontage road, with an added southbound intersection bypass lane and reconstruct entrance and exit ramps.
• More turn lanes will be constructed at the Parmer Lane and Lamar Boulevard intersection.
• Bicycle and pedestrian enhancements will be made as part of the project.

The construction project is funded by TxDOT’s Texas Clear Lanes Congestion Relief Initiative and the Capital Area Metropolitan Planning Organization. The project is expected to be complete mid-2021, weather permitting.

The groundbreaking ceremony is scheduled on Wednesday, July 24, at 10 a.m. at 12415 North I-35 along the northbound frontage road.

A diverging diamond interchange (DDI), also called a double crossover diamond interchange, is a type of diamond interchange in which the two directions of traffic on the non-freeway road cross to the opposite side on both sides of the bridge at the freeway.

The state transportation agency has opened a couple of the traffic-calming devices across the Austin area in recent years. One was opened last year at the intersection of Slaughter Lane and MoPac, with another opening at the intersection of Interstate 35 and RM 1431/University Boulevard in Round Rock in 2016 — the first of its kind in Central Texas.

TxDot officials previously produced a video to prepare Round Rock drivers on driving through the DDI:

Here's what the Round Rock DDI looks like:

Graphic courtesy of Texas Department of Transporation.