Because this is Austin, it will probably never happen (NIMBYs to the tenth power) but its an interesting plan. Reminds of the HOV lane in Houston that goes from I-10 to downtown.
http://ftpcontent3.worldnow.com/ktbc/PDF%20Files/Select_MoPacSouth_Exhibits.pdf
News article about it
http://www.myfoxaustin.com/story/28329896/a-double-deck-and-more-tolls-could-be-in-the-works-for-mopac-expressway
Official project web site,which includes schematics
http://www.mopacsouth.com/ (http://www.mopacsouth.com/)
I think this project will proceed to construction. The reasons are because it is tolled (officials never skip an opportunity to charge more tolls), there is an urgent need for more capacity, and the planned SH 45 toll road is going to connect to the south end of MoPac, dumping more traffic on the road.
I expect the main source of protest to be the upper elevated structure through Zilker park. If the the project is blocked, that will be the reason.
Looks like Austin is trying to create a toll beltway around the city (along with SH 130) a la Orlando. My sympathies...
Just to think, most of these could have been non-tolled if the NIMBYs would not have blocked construction several decades ago.
After a long pause, planning for the Mopac South project is restarted. The recommended alternative was revealed today.
The public meeting (https://storymaps.arcgis.com/stories/e3c28bf66389442ab942075eea02e66c) materials are online. I don't see schematics, but the 13-minute video (https://www.youtube.com/watch?v=HqeD7VJhbSQ&t=695s) shows all the detail.
This project adds 2x2 tolled express lanes from downtown to Convict Hill Rd, and 1x1 tolled express lanes from Convict Hill Rd to Slaughter.
Observations
- Interchange at US 290: The existing main lanes become the toll lanes. New structures are built for the main lanes close to the existing frontage roads. Unfortunately these structures match the existing lane count of two each way. The westbound-southbound ramp is substantially modified and lengthened. There is a new elevated structure connecting the toll lanes to US 290 on the west wide of the interchange.
- Barton Creek crossing is 4-2-2-4 but appears to lack a northbound shoulder.
- At Loop 360, the express lanes are together alongside the northbound main lanes.
- There are elevated connection structures north of Barton Skyway.
- No elevated structures at Zilker Park and Lake Lady Bird
- Lake Lady Bird bridge is 5-1-1-5
- No new connection ramps at the downtown interchange complex. However, there is a new tight-radius loop on-ramp below ground level from westbound Cesar Chavez to southbound Mopac.
- It appears there is no right-of-way acquisition in this project
- The toll lanes have a shoulder.
- There are some minor non-tolled improvements throughout the corridor, such as short sections of new general-purpose lanes, U-turns and ramp improvements. These are listed in the presentation.
- There is no mention of schedule or cost.
While this project isn't everything it could be (or needs to be), we're dealing with Austin, so I think the recommendation is a good outcome overall. Of course, it needs to actually proceed to construction, and opposition efforts to delay or suspend the project are possible.