ENVIRONMENTAL STUDIES

TTC-35 Study Timeline | I-69/TTC Study Timeline

Overview of Tiered Approach

All environmental studies undertaken by TxDOT follow the stringent federal rules of the National Environmental Policy Act.  Studies for the Trans-Texas Corridor will be no different.

Right now, TxDOT is conducting separate environmental studies on two TTC projects: TTC-35 and TTC-69.  Both will follow the same environmental process that includes two tiers of study, each offering extensive opportunities for the public, elected officials and other interested parties to comment.

Tier One

The goal of Tier One is simply to narrow the broad study area. In Tier One for TTC-35, the study area will be narrowed from 50-60 miles wide to approximately 10 miles wide.  For TTC-69, the Tier One study area will be narrowed from 20-30 miles wide to approximately four miles wide.

To identify a narrowed study area, detailed environmental analysis is conducted in Tier One.  This starts with a thorough documentation establishing the project’s purpose and need. Subsequent analysis focuses on land use, engineering and design, traffic flow and potential impacts on environmental factors (such as wetlands, farmland soils, cultural resources and socio-economic issues.) Throughout the process, public opinion is also considered.

Once the analysis is complete, a draft environmental impact statement is prepared which identifies the narrowed study area.  Once the draft report is approved by the Federal Highway Administration, hearings are held to give the public a chance to review the draft report and provide their comments.

The draft report is just that – a draft.  The narrowed study area could change based on new information and public comments obtained during the hearings on the draft report.  This is why it is the public is encouraged to attend the hearings and participate in the decision-making process.

If there are no significant changes to the study area, then a final environmental impact statement is submitted to the Federal Highway Administration.  If FHWA approves the findings of the final report, it will issue a Record of Decision, affirming the final environmental impact statement.

Tier Two

Once Tier One is completed, the federally-approved narrowed study area serves as the basis for the Tier Two environmental studies.  The goal of Tier Two is to identify a final project route from the narrowed study area approved in Tier One.  

Separate Tier Two studies will be conducted for each individual section of road, rail and utilities.  These studies will be initiated as needed based on transportation demand, and thus will be staggered over time.

The environmental process in Tier Two is identical to Tier One, providing multiple opportunities for public comment before final decisions are made.  Tier Two studies, as approved by FHWA, will result in final project routes and will authorize construction.