Williamson County commissioners voted Aug. 18 to formally support the expansion of I-35 through the county, a project led by the Texas Department of Transportation and sent the department a list of requests. Requests from county commissioners are treated as formal proposals, though are not legally binding.
About the project
Commissioners requested that the expansion include at least two additional non-tolled lanes in each direction, two managed lanes in each direction, and collector or distributor roads through Round Rock, according to county documents.
While managed lanes could include tolls, High-Occupancy Vehicle or express lanes, Precinct 1 commissioner Terry Cook clarified that the court requests that TxDOT not move forward with HOV lanes.
“All lanes should be available at all times for all people,” Cook said.
The project will support the region’s population growth, which increased by 23.6% from April 2020 to July 2025 and is projected to exceed 1 million residents by 2045, documents state.
This population growth is expected to increase average daily traffic on I-35 in the Austin area from 244,450 vehicles in 2018 to around 367,900 by 2050, according to county documents.
What residents need to know
The deadline to submit formal comments regarding the project is Aug. 28, Precinct 2 Commissioner Cynthia Long said.
“Please, if you care about the congestion that is already there on I-35 through Williamson County, you can email [TxDOT] ... the easiest way to do that is just say I support the Williamson County Commissioners' resolution,” Long said.
Residents can submit comments via email at [email protected].
