About the MoPac South Environmental Study

The Environmental Study being conducted on this project is an Environmental Assessment (EA) per the National Environmental Policy Act of 1969 (NEPA). An EA is a public document that includes an analysis of a full range of alternatives (including a “no build” alternative) and an assessment of potential impacts to the human and natural environment. An EA is prepared for projects for which the significance of the environmental impact is not clearly established, and, if a build alternative is approved, results in a “Finding of No Significant Impact” (FONSI). Public involvement is a crucial element of the EA process.

Please note, a glossary of NEPA terms is available to use while reviewing the information on this website.

PURPOSE AND NEED

PROJECT GOALS AND OBJECTIVES

• Provide consistency with local and regional plans
• Be constructible without unnecessary impacts to the natural and human environment
• Reduce congestion delays and provide travel time savings for all roadway users
• Support water quality by treating 100% of TSS annual loading for all new impervious cover
• During project development, work to exceed goal
• Deliver relief in a timely manner
• Facilitate congestion management
• Increase opportunities for transit, ridesharing, pedestrians and bicyclists

What are we trying to do?

• Provide an opportunity for reliable travel times
• Improve operational efficiency
• Create a dependable and consistent route for transit
• Facilitate reliable emergency response

What problems are we trying to address?

• Current and forecasted congestion levels are creating unreliable travel times
• Under the No-Build Alternative (Do Nothing), it could take 30%-42% more time to travel between Cesar Chavez Street and Slaughter Lane by 2045
• Emergency response times are impacted by traffic congestion
• Forecasted population and employment growth in Travis and Hays counties

ALTERNATIVES CONSIDERED

The preliminary alternatives proposed for the Study were:

• Add General Purpose Lane(s) in each direction
• Add High Occupancy Vehicle (HOV) Lane(s) in each direction
• Add Transit Only Lane(s) in each direction
• Add Express Lane(s) in each direction
• Transportation Systems Management (TSM)/ Transportation Demand Management (TDM)
• • TSM: a collection of low-cost (non-capital intensive) strategies to enhance safety, reduce congestion and improve traffic flow
  • TDM: managing or decreasing the demand for auto-related travel by using a variety of measures to increase the operating efficiency of transportation facilities
• No-Build, or “do nothing” alternative

REASONABLE BUILD ALTERNATIVE

Based on initial evaluation, the Express Lane(s) Alternative, along with the High Occupancy Vehicle (HOV) Lanes Alternative and the Transit Only Lanes Alternative were carried forward for further evaluation because each met the Purpose and Need for the project. Each of the three remaining alternatives were evaluated further using the project Goals and Objectives and other criteria. 

As a result of this evaluation, the Express Lane(s) Alternative was selected as the Reasonable Build Alternative because it:  

• Offers reliable travel times for single occupancy vehicles, vanpools, busses and emergency vehicles
• Provides the shortest peak period travel time for all vehicles, including those using the general-purpose lanes
• Provides over 3 million hours of annual travel time savings for all users compared to the No Build Alternative. That’s about 1.7 times more savings than HOV Lanes and 13 times more savings than Transit Only Lanes
• Avoids unnecessary impacts to the natural and human environment and avoids and minimizes impacts to water quality
• Increases opportunities for transit and ridesharing and includes new bicycle and pedestrian facilities
• Aligns with the 2045 Traffic Forecast Update 

Check out the MoPac South Environmental Study Open House #3 (February 26, 2015) Display Boards to learn more about the alternatives evaluation process and the recommendation of the Express Lane(s) Alternative.

The No Build alternative continues to be carried forward as a baseline for comparison and an option for approval. Under this scenario, routine maintenance of the corridor would continue. This alternative also assumes any other improvements/strategies in the Capital Area Metropolitan Planning Organization’s Long Range Transportation Plan would move forward.

NEXT STEPS

The project team will continue to analyze and ultimately identify the best express lane(s) operational configuration option using technical analyses and public input.

When a Recommended Build Alternative is selected, the study team will complete the draft Environmental Assessment. This document demonstrates an analysis of the alternatives considered, and presents an assessment of potential impacts to the human and natural environment. When complete, this draft document will be presented at a public hearing for input. With support from its partners, the Mobility Authority will make a final recommendation to TxDOT for their review.