In compliance with the National Environmental Policy Act of 1969 (NEPA), TxDOT
and the Mobility Authority completed an Environmental Assessment for the
MoPac Corridor from Cesar Chavez Street to Parmer Lane in August 2012. The
study began in July 2010 with the consideration of a full range of
alternatives for improving mobility in the corridor, including adding
multiple lanes or a high occupancy vehicle (HOV) lane, as well as making no
improvements at all.
The environmental study found that Express Lanes with variable
pricing were the preferred alternative for addressing long term
mobility issues in the corridor. The study also identified where sound
walls were needed to reduce roadway noise and where bicycle and pedestrian
facilities needed to be improved. The study also identified aesthetic
improvements for the corridor.
In August 2012, the Federal Highway Administration (FHWA) issued a
finding of no significant impact
(FONSI), approving this preferred alternative for implementation and
Public involvement is a critical element of the environmental study
process. Between 2006 and 2012, the MoPac Improvement Project Team
conducted more than 30 open houses, public meetings, and neighborhood
presentations. The public involvement process involved discussing various
alternatives with the public and gathering feedback. Public feedback was
then combined with technical analyses to identify the best option for
improving MoPac. The recommended alternative was then subjected to
additional public review and scrutiny, ultimately leading to the selection
of Express Lanes as the preferred alternative. A final public hearing on
the environmental study and the proposed Express Lanes was held on May 23,
2012 at O. Henry Middle School.
For more on the public outreach activities that took place during the
environmental study phase, please see Chapter 5 of the Final Environmental Assessment and our
Past Events page.
FINAL ENVIRONMENTAL ASSESSMENT 2012
Some sections of the document are rather large, so download times may
FONSI REEVALUATION 2013-2014
During the design phase of the project, four design modifications were
identified for consideration:
- The Express Lane entry and exit ramps
into and out of downtown Austin would be changed from traversing over
the main lanes of MoPac to going under the main lanes of MoPac.
- The configuration of the southbound
exit to Cesar Chavez Street and 5th Street would be modified to allow
Express Lane traffic to exit to either Cesar Chavez Street or to 5th
Street. The change would remove a merge condition and improve
- An existing 42-inch water line between
35th Street and 45th Street would be abandoned in place and a new line
constructed outside the MoPac right-of-way.
- The northbound exit ramp and access
road to Steck Avenue would be slightly realigned, with no change in
These modifications required FHWA approval under an environmental
reevaluation process before implementation. After a review of the
environmental documentation and in consideration of public comment from an
Open House held on September 5, 2013, FHWA agreed in early 2014 that the
FONSI designation remains valid. These four design modifications will now
be built as part of the overall MoPac Improvement Project.
The federally approved FONSI Reevaluation document can be downloaded and
reviewed as follows: