Project Overview


Population growth in northern Hays and southern Travis counties increased by approximately 200% between 1990 and 2010. This rapid growth has increased traffic congestion in the area. According to the Capital Area Metropolitan Planning Organization (CAMPO), population in this area is expected to increase further, by approximately 86% by 2035.

As a result of growth and development, drivers are using local roads, such as Manchaca Road, Slaughter Lane and Brodie Lane as commuter corridors, in some cases to access MoPac to get to downtown Austin. These local roads have become increasingly congested. Signalized intersections on the local roads exacerbate the traffic problem. Some neighbors have also expressed concerns about cut-through traffic, as well as the inability to safely exit their neighborhoods.

Motorists need improved system connectivity and an efficient alternative route to congested local roadways.


The Texas Department of Transportation (TxDOT) is working with the Central Texas Regional Mobility Authority (Mobility Authority), and regulatory agencies to study a possible solution for improving mobility in the rapidly growing area of northern Hays and southern Travis counties. This combined effort includes an environmental study of an area between MoPac and FM 1626. The study will consider environmental impacts, constraints, the needs of drivers, and concerns of surrounding neighbors. Potential impacts from construction and operation will be evaluated.

Throughout the study, the community will be consulted on a variety of elements, for example, the Purpose and Need, the alternatives being studied, bicycle and pedestrian accommodations, transit accommodations, aesthetics, noise analysis, environmental issues, neighborhood access and roadway design. Community outreach and public input is critical to the process.


Build Alternative: A new toll road on existing state-owned right-of-way

The facility would be a limited access, four-lane divided toll road. The build alternative would include water quality protection and Best Management Practices throughout (please visit our page on water quality). You can view a conceptual rendering of the build alternative as well as maps here.

The No-Build Alternative: Under this alternative, the project would not be built.

This option serves as a baseline to indicate the consequences if no action is taken. 


The following two draft traffic studies are available for your download and review:

Please note, due to the large file size, download times on some of these items could vary. If you have any technical difficulty downloading these meeting materials, please email us and select “general inquiry” or call 512-593-4202.


In July 2011, the Mobility Authority, in partnership with TxDOT, hosted the Green Mobility Challenge, a design competition that was conducted to identify innovative ways to build, operate and maintain future transportation projects, including SH 45SW. If the environmental study results in the recommendation of a build alternative, a number of innovative ideas will be considered, including some generated from the competition. For more information about the Green Mobility Challenge, visit


The environmental study will consider many resources, for example:

  • The Edwards Aquifer and other groundwater resources
  • Floodplains
  • Vegetation
  • Wildlife
  • Land use
  • Threatened and endangered species
  • Aesthetic and visual resources
  • Surface water
  • Historic and archaeological resources
  • Potential displacements to residents and businesses
  • Air and noise impacts from potential construction and operation


  • Protect the Edwards Aquifer from the potential effects of construction and subsequent operation of the roadway
  • Develop the project in an environmentally-sensitive manner
  • Minimize impacts to neighborhoods and existing development
  • Minimize impacts to Water Quality Protection Lands

Please download: FACT SHEET: SH 45SW-July 2014

Contact Us

Texas Department of Transportation
P.O. Drawer 15426
Austin, TX 78761-5426

(512) 593-4202 Email Us
Contact Us

Texas Department of Transportation
P.O. Drawer 15426
Austin, TX 78761-5426

Call (512) 593-4202
Email Us