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Mobility Authority Begins Construction on 183A Phase III Project

New connection to deliver proactive congestion relief

(Austin, Texas) — Construction on the Central Texas Regional Mobility Authority’s (Mobility Authority) 183A Phase III Project has begun along US 183 in Williamson County. This long-term mobility improvement project will extend the 183A Toll Road 6.6-miles northward from Hero Way in Leander to north of SH 29 in Liberty Hill, delivering greater mobility and connectivity for all.

With unprecedented regional growth, most notably in Cedar Park, Leander, and Liberty Hill, traffic volumes along US 183 are anticipated to increase by 183 percent by 2042, driving the need for proactive congestion relief.

“We’re proud to be ahead of the curve on this project,” said Bobby Jenkins, Chairman of the Mobility Authority Board of Directors. “Just as we delivered meaningful relief with the initial phases of 183A, extending the roadway will accommodate future growth and ensure that the mobility needs of our region are met long into the future.”

The 183A Toll Road was the Mobility Authority’s inaugural project, first opening to traffic in 2007. Phase II of the 183A Toll road opened in April 2012, more than seven years ahead of schedule, quickly reducing gridlock and travel times. 183A Phase III is designed to build upon this success.

The $277.3 million project includes construction of two tolled lanes, an adjacent shared use path, and aesthetic enhancements along the corridor. The new lanes will be located between the existing non-tolled frontage roads and primarily within the existing right-of-way in the median of the US 183 corridor, mitigating disruption to the public during construction.

The project is anticipated to open to traffic in 2025, freeing up capacity on US 183 and adjacent roadways.

To stay informed of project progress, drivers can sign up for the project newsletter, and follow the project on Twitter @183AToll.

For more information on the project, visit


The Central Texas Regional Mobility Authority is a local, independent government agency created in 2002 to improve the regional transportation system in Travis and Williamson counties. The Mobility Authority implements innovative and sustainable transportation options to enhance quality of life and economic vitality in Central Texas. The Mobility Authority operates 183A Toll, 290 Toll, the 71 Toll Lane, the MoPac Express Lane, the 45SW Toll Road, and the 183 Toll Road. The agency is constructing the 183A Phase III Project and will soon begin the 183 North Project. For more information about the Mobility Authority, visit

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