Don’t be fooled. Stop 45 SW and the conversion of Mopac into a second I-35!

State highway planners are trying to pull a fast one on Austin. At different times they talk to the public about five separate toll projects in southwest Austin, but they rarely connect the dots. The reality will be a massive 12-to-16 lane, partially tolled highway loop from I-35 south of Austin west to Mopac and north to Lady Bird Lake and beyond.


Once it’s completed, and the traffic floodgates open, we can kiss Austin’s quality of life goodbye. As traffic expert Mike Brown says, if South Mopac is connected to I-35 by constructing the proposed SH 45 SW, then traffic on Mopac will “explode” and you simply cannot add enough lanes to Mopac to accommodate all of the traffic.




South Mopac currently ends just south of the Lady Bird Johnson Wildflower Center. (See map.) As a result, Mopac serves primarily local commuters in western Travis and northwestern Hays County. If South Mopac is connected to I-35 by constructing the proposed SH 45 SW toll road, Mopac is converted into a second Interstate 35 through Austin serving inter-regional and interstate truck and auto traffic. The lanes fill up almost immediately. Current Mopac commuters, especially those using Mopac for shorter commuters, suffer more harm than good.


The current plan is to expand Mopac to 12-to-16 lanes, more than I-35 through Austin, with wide shoulders that could be converted to even more lanes. The harm down to central Austin neighborhoods by I-35 would be duplicated along Mopac.


Our local toll road authority, the CTRMA, is rushing to build this tolled loop conversion of Mopac into a second I-35. But they don’t want you to know about it. They have chopped up this eighteen (18) mile long project into four separate pieces for purposes of environmental studies and public comment.


They pretend like these pieces do not add up to a whole loop. They know, when the public sees the whole thing, then it becomes clear that much damage will be done, including:


*The 45 SW/Mopac toll loop project will degrade Austin’s beauty and image while actually making our traffic worse.

*It will put up over 50,000 extra cars a day on South Mopac, which will become a second I-35---a major interregional expressway roaring through the city.

*It will add 18 wheelers and massive tractor trailer rigs to Mopac traffic.

*It will divert over a billion dollars that could be used on much needed road improvements in other parts of Travis and surrounding counties.

*It will build a grotesque double-decker bridge over Lady Bird Lake and Zilker Park, with a huge flyover looming over and wrapping around Austin High School.

*It will put Lady Bird Lake trail users in a dark, noisy concrete “cave” under the Mopac bridge, with huge new pillars and extra traffic lanes overhead --converting a pleasant experience into an ugly, stressful one.

*It will choke lakeside traffic by dumping thousands of extra cars a day onto Cesar Chavez Street, creating pressure to cut into parkland in order to widen traffic lanes---not to mention creating a massive traffic problem at the intersection of Cesar Chavez and Lamar Blvd.

*It will allow the regional toll road authority to force four unwanted toll lanes on Austin and Travis County despite overwhelming local opposition.

*The new “dynamic pricing” scheme will cost up to $12 or more during rush hour, serving as true “Lexus Lanes” for the few and providing no benefit for others. (The CTRMA will actually make more money the worse traffic is on the free lanes.)

*It will destroy the tranquility and beauty of the Lady Bird Wildflower Center, one of Austin’s environmental treasures.

*It will pave and pollute Barton Springs and the Barton Springs Edwards Aquifer recharge zone, while spurring more harmful urban development and pollution over the aquifer in Texas most vulnerable to pollution.

*It will harm and further threaten extinction of the Barton Springs and Austin blind salamanders, while destroying endangered Golden-cheeked warbler habitat.

*It will degrade one of Austin’s most iconic parks---Zilker Park, site of world famous music events, Zilker Botanical Gardens, and the Austin Nature & Science Center.

*It will take hundreds of millions of dollars in limited transportation funds away from higher priority projects that benefit traffic flow rather than make it worse for most drivers. Toll collections will only finance a fraction of the costs; half or more of the costs of the 45SW/Mopac toll loop project will be paid for with limited tax dollars.

There is a better way.

TxDot should follow the recommendation of its own blue ribbon panel made back in 2011. This Advisory Council plan called for removing the tolls from SH 130 and SH 45 SE and designating this route as Interstate 35, making it the preferred route for through traffic from south of Austin north to Georgetown and beyond. This could be done quickly, with immediate benefits to I-35 traffic in central Austin while supporting development in preferred growth areas in eastern Travis County. There would then be no need to convert Mopac into a second Interstate 35.


Traffic flow on Mopac can be improved by utilizing the existing pavement to add an HOV lane for rush hour traffic, making intersection improvements at the Slaughter Lane and LaCrosse intersections, investing more in telecommuting, ride share, and transit options, and advancing the Lone Star Rail project connecting Austin with San Antonio.


At the same time, the local toll authority (CTRMA) should make public all of its financial and traffic studies for Mopac, 45SW, 290 West, and SH 71 West, so that the public can see the full extent of its planning. Then the public will learn the true cost and nature of this huge project.


Before any part of the 45SW/Mopac toll loop is built, we need a comprehensive environmental impact study to examine all of the environmental, social, economic, and financial costs and benefits of converting Mopac to a second, partially tolled I-35 through Austin. This comprehensive study must take a solid look at alternatives that improve north south traffic flow along with I-35 corridor without ruining Mopac and the natural and cultural resources and neighborhoods along Mopac.


Why we need to Keep Mopac Local:
This is a classic case of myopic toll road planners ruining a city in order to ”save" it.  If built, the 45SW/Mopac toll loop will make Austin uglier while making traffic worse. It will further segregate Austinites economically, providing transportation welfare to the wealthiest while doing little for others and actually harming current Mopac commuters who either cannot afford the tolls or only take shorter commutes on Mopac that the toll lanes will not serve.


It’s the wrong toll road in the wrong place at the wrong time. Unplanned growth has produced big traffic problems for Austin, but this scheme won’t help; it will actually hurt the city.


“Pave Paradise and Put Up A Parking Lot” should be the honorary title of the South MoPac phase of the project. It’s everything that Austin’s not supposed to be. While other cities are tearing down waterfront freeways, Austin would be pouring rivers of concrete along one of its most iconic and beautiful stretch of shoreline—an area of tremendous environmental and economic value to the city – not just on Mopac itself but in expanding Cesar Chavez from Mopac all the way into downtown. (See video depiction here)


The four extra toll lanes are being proposed as a means of easing Austin traffic. In reality they will choke Central Austin by pouring thousands of extra cars onto Caesar Chavez and Fifth Streets, which are too small to handle the enormous increase in traffic.  Because there’s not enough right of way on Fifth St., the only way to “fix” this nightmare will be to widen Cesar Chavez St., cutting into parkland and further ruining the tranquility and beauty of Lady Byrd Lake, a renowned Austin landmark.


In short, we are being asked to sacrifice our heritage and degrade the city’s quality of life so we can move Hays County toll traffic into the city faster and cut ten minutes off regional travelers driving from San Antonio to Dallas (or from I-35 south of Austin to the 183 corridor north of Austin).


You can help make sure this doesn’t happen by taking action today at this link.

Double Decker Austin

Flint Ridge Cave Recharge

Video showing the Flint Ridge Cave recharge feature.

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