A wistful Austin bumper sticker reads, "Visualize I-35 as a hike and bike trail." The Reconnect Austin proposal might offer Downtown the next best thing: an underground I-35 topped with a tree-lined boulevard. But the plan's true feasibility is up for debate.
A bit of backstory: The Texas Department of Transportation is planning to expand I-35, with the goal of construction beginning around 2020. It's considering two main alternatives for the stretch through Central Austin, each of them adding an additional lane in each direction. The first is a "modified existing" rebuild that elevates the southbound lanes at Cesar Chavez and widens the existing elevated freeway through Eighth Street. The other is a "fully depressed" alternative that sinks the lanes below grade and keeps the frontage roads where they are, but allows for the later addition of intermittent caps like Klyde Warren Park in Dallas (see "Think About It Bigger," Jan. 17).
A group of local architects and planners, known as Reconnect Austin, is urging TxDOT to consider another alternative. Their plan sinks I-35 below ground level, builds a one-mile-long cap over the top of it, replaces the frontage roads with a boulevard on top of the cap, and develops the right-of-way formerly occupied by the frontage roads. The group says the redeveloped right-of-way – 30 acres total – would help pay for the construction project.
The plan, described in the Jan. 17 issue of the Chronicle (see "Reconnect Austin: Part One"), purports to add aesthetic and economic value to the freeway rebuild. But TxDOT has declared it "technically infeasible," and its full effect on Downtown traffic is unknown. The groups agree that the freeway can be depressed, but that's where their agreement ends. Without consensus, it's unlikely the Reconnect plan will become anything more than a vision.
The first question about any changeto I-35 is how much it would improvetraffic. An August 2013 report by theTexas A&M Transportation Instituteexamined the Reconnect plan's ability to handle traffic through Central Austin and concluded that it would neither improve nor worsen congestion.
The TTI study developed out of Rider 42, a transportation appropriation from the 2011 legislative session to find long-term solutions for Texas' most congested roadways, including I-35 in Austin. The study focused on I-35 through Central Texas and modeled seven potential traffic scenarios for the year 2035. The outcome was bleak: The models predicted such debilitating congestion that engineers called it unsustainable and predicted it would have a chilling effect on the region's growth.
All seven models assumed the public transit options in the CAMPO 2035 plan – commuter rail, bus rapid transit, streetcars, and intercity rail – would be operational. And every modeled scenario, except one adding six new underground tolled express lanes through Austin, was insufficient to address the gridlock projected if Austin's population growth continues at the current pace.
The study disputes the idea that rerouting through traffic – including trucks – to SH 130 would fix congestion on I-35. Two of the seven scenarios it examined considered turning SH 130/SH 45 into the interstate, removing the tolls on those roads, and converting some or all of I-35's lanes to toll lanes. But researchers discovered that more than 80% of I-35 traffic consists of local commuters who can't be diverted to SH 130.
The solution, engineers said, would be a six-lane tunnel or a remake of I-35 plus radical changes in commuter behavior. These changes would require individual as well as institutional commitment: a 40% increase in telecommuting; a 30% reduction in university commuter trips (replaced by online classes); and a 25% increase each of transit, HOV, and bike/pedestrian trips. In other words, there's no silver bullet for our congestion problem, only a spray of silver buckshot.
For the piece of the puzzle that remakes I-35, the Reconnect plan, also called the "Downtown Austin Alternative" in the report, performed as well as "Scenario 2." Both added one managed express lane in either direction through Central Austin, and both reduced congestion by 5%.
To Sinclair Black, the mastermind behind Reconnect Austin, those results meant "the biggest opportunity [for TxDOT] to block it on the basis of 'well, you just don't have the capacity' was behind us."
But the Downtown alternative performed well precisely because it was modeled after Scenario 2, says Ginger Goodin of TTI – not because of the freeway cap itself, or any of the non-highway elements that focus on design and economic development. To suggest that Reconnect's plan reduces congestion, without providing context (as we did in part one of this piece), is misleading, says Goodin, who facilitated the Austin-area study.
"The Downtown Austin Alternative did not have any effect on traffic – zero. It didn't make it worse, but it didn't make it better," Goodin says. "The results mirror the express lanes [in Scenario 2] because that's essentially what we modeled, with some modifications to ramps and other things that were proposed in the Downtown alternative. When you compare the Downtown alternative to the others, wow, it looks pretty good, it's a five percent reduction in network delay – but that's what the express lanes gave us."
If official studies are agnostic on Reconnect's effect on traffic, they're more definitive on engineering. TxDOT's assessment of the plan is that it's "technically infeasible."
"It doesn't meet our current set of freeway standards," says Terry McCoy, deputy district engineer for TxDOT. "The lanes and shoulders have to be a certain configuration [Reconnect] haven't accounted for, and there's no way to build this and maintain traffic."
One of the sticking points is ramps. The Reconnect plan would remove some or all of the entrance and exit ramps to I-35 between 15th Street and Holly Street. Drivers who wanted to go Downtown would exit before the tunnel and use the boulevard on top of it, or other streets in the Downtown grid.
As part of the I-35 rebuild, TxDOT does plan to reduce the number of ramps in Downtown, McCoy says. Many of them don't function very well in today's traffic volume. But "what we can't do is simply close all the ramps down," because to do so would overload the frontage roads. Reconnect argues that, under its plan, traffic would disperse to other city streets in the Downtown grid, which would be connected across the freeway-topping cap. TxDOT says its analysis of the boulevard concept resulted in "unacceptable intersection operations" and that previous city of Austin studies have indicated Downtown doesn't have the capacity to absorb the traffic.
But the ramps aren't the extent of the disagreement. Between Eighth and 11th streets, a 26-foot difference in elevation between the northbound and southbound access roads would make it difficult to build a level cap, McCoy says. And perhaps the biggest problem is that TxDOT says the space needed to accommodate underground lanes is much wider than Reconnect has estimated. Because so much space is needed, the agency says, it isn't actually possible to turn leftover right-of-way into developable land.
When TxDOT drew its own hypothetical capped I-35 to see if it was feasible, it included engineering elements required for freeways: a ventilation system, structural supports to hold up the cap, barriers to protect those columns, separation between the regular and express lanes, a collector-distributor lane, utility corridors, and a drainage structure. "As you add those additional required elements," McCoy says, "that 'extra' right-of-way starts to diminish." He says the leftover right-of-way is far less than Reconnect's calculation of 100 feet on each side – more like 5 feet on one side and 30 on the other. And surface land cannot be sold or leased if it has freeway or utilities underneath it.
Reconnect Austin's Heyden Walker suggests that at the root of TxDOT's objection is its reluctance to give up right-of-way.
TxDOT does want to protect its right-of-way, says McCoy. "We know that once we give up right-of-way on I-35 we'll never be able to get it back," he says. "It's almost impossible to purchase right-of-way." But even if you did redevelop the land where the frontage roads are today, he says, existing facilities like University Medical Center at Brackenridge and hotels along the freeway would constrain what could be built next to them. And any businesses that currently have frontage road access would have to be compensated if the road were removed.
The "fully depressed" alternative TxDOT is considering does enable the eventual construction of intermittent caps across the sunken freeway. Instead of a continuous, one-mile cap, a series of wide decks could be built, on top of which could be parks, like Klyde Warren in Dallas. But because the whole highway wouldn't be capped, the frontage roads would stay where they are now, and the option of "reclaiming" the land and using it to pay construction costs wouldn't exist.
In some senses, capping chunks of the freeway is a compromise option. The freeway is neither expanded where it is elevated through Downtown, nor completely sunken and capped. "What we did is break down the Reconnect Austin proposal to see what could and what couldn't work," McCoy says. "The Reconnect Austin proposal has some very attainable goals and components, and we've tried to accommodate as many of those as we can."
To Black, the idea of intermittent caps is "an artificial defensive move" rather than a compromise. "Just like widening the right-of-way was intended to wipe out the value-creation argument, the partial cap is intended to displace the boulevard discussion," he says. "The only good thing about a partial cap is that it is an absolute final word that [I-35] is going to be depressed. That's the biggest win of all."
How much would it cost to do all this?
Reconnect based its $600 million cost estimate on two completed TxDOT projects in other regions of the state. The team based their projection for sinking the freeway on costs for a depressed freeway in Houston, and their estimate for the cap on the per-square-foot cost of the deck that holds Klyde Warren Park in Dallas.
TxDOT's preliminary estimate for depressing I-35 and adding intermittent decks is $734 million in 2013 dollars. The Reconnect team's estimate for capping is lower than TxDOT's intermittent caps because, Walker says, they're based on different assumptions about the right-of-way. Because the Reconnect plan uses the same footprint for the freeway lanes and frontage roads, the span to be capped would be longer and narrower.
If I-35 were depressed, the caps would likely be built later, unless funding materialized at the same time the lanes were sunk. And the city of Austin would likely be responsible for the funding. "The capping itself does not improve operations, so it's really an amenity," McCoy says. "We would expect the locals to pick up the cost for that."
While construction likely won't start until 2020 – McCoy says the agency doesn't want to tear up I-35 Downtown until it's completed work on Highway 183 and MoPac north – the next step is environmental studies of the two plans TxDOT considers technically feasible. That roughly three-year process will result in a decision about which construction plan to use. Reconnect Austin and its allies – civic groups whose memberships Walker says represent 23,000 people – are asking TxDOT to add the Reconnect plan to the two advancing to the environmental study stage.
"We respect what they've tried to do, but it's not really a democratic process," McCoy says. "It doesn't matter how much people like this, if it's not technically feasible and it falls apart for all the reasons we say it falls apart, it's not something we can actually do." He says TxDOT has done its best to incorporate elements of the Reconnect plan into its depressed lane scenario, and adds, "We hate to see this as an 'us versus them' – we really view this as an 'us and us,' working together to try to find a best possible solution."
The camps have yet to find common ground. "Somewhere that technical side that TxDOT's talking about and the urban planning side that Sinclair's talking about, we're going to have to find a way to translate that and meet in the middle," says TTI's Ginger Goodin. "[We need to] make sure there's understanding among all these players who are very passionate about doing what's right. Can we bridge the gap in the language so we can develop the best solution?"
Compared to the distance across I-35, that may be a much wider gap to bridge.
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