Notice of Availability - 183 North Mobility Project Finding of No Significant Impact
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Notice of Availability - 183 North Mobility Project Finding of No Significant Impact

Purpose: This notice is to advise the public that TxDOT has issued a Finding of No Significant Impact (FONSI) for the proposed 183 North Mobility Project from State Loop 1 (MoPac) in Travis County to State Highway (SH) 45/Ranch-to-Market Road (RM) 620 in Williamson County, Texas.
Description: The proposed 183 North Mobility Project would include the construction of two variable-priced express lanes in each direction, an additional (fourth) general purpose lane (southbound from approximately Lake Creek Parkway to the entrance ramp from SH 45; southbound from north of McNeil Drive/Spicewood Springs Road to MoPac; and northbound between Braker Lane and McNeil Drive/Spicewood Springs Road) and direct connectors to and from SH 45/RM 620 on the north and MoPac on the south. Transitions between the improved section of US 183 and existing facilities would be provided along SH 45/RM 620, MoPac (south to RM 2222) and on US 183 north and south of the project area. The construction of shared use (bicycle/pedestrian) paths and sidewalks are also included in the proposed project.


In order to avoid noise impacts that may result from future development adjacent to a proposed highway project, a traffic noise analysis is included in this Environmental Assessment (EA), which includes predicted noise impact contours for currently undeveloped areas. These impact contours are intended as a general guide to assist local planning officials and developers plan and construct new activities in locations that would not result in traffic noise impacts.

It is important to note that on the date of approval/clearance of an environmental document (including the traffic noise analysis) for a proposed highway project; TxDOT is no longer responsible for providing noise abatement for new development.

Copies of the FONSI, approved Final EA, Certification of Public Involvement, and supporting documentation are available for public inspection at TxDOT, Austin District, 7901 North I-35, Austin, TX 78753, the Central Texas Regional Mobility Authority, 3300 North I-35, Suite 300, Austin, TX 78705, and on the 183 North Mobility Project website at For further information, please contact Heather Ashley-Nguyen, P.E, TxDOT Austin District Transportation Engineer, CTRMA Liaison at (512) 658-1516 or by email provided on notice below.

The environmental review, consultation and other actions required by applicable Federal environmental laws for this project are being, or have been, carried out by TxDOT pursuant to 23 U.S.C. 327 and a Memorandum of Understanding dated December 16, 2014, and executed by FHWA and TxDOT.

Contact: TxDOT Austin District
Public Information Office

(512) 832-7060


Posted May 5, 2016.