Traffic on I-35 at night in downtown Austin. Photo by James Rambin.
You probably woke up today to an Interregional Highway 35 choked with cars and caked in soot, a resonant cacophony shaking the bones of unlucky passers-by. Along its frontage roads, crumbling sidewalks exemplify the lack of investment for the pedestrians struggling to navigate its shadows. And you’ll probably wake up to it tomorrow.
It’s a car’s life on I-35’s frontage roads. Photo by Caleb Pritchard.
I-35 can have a better future if the will exists to redesign it for the use of the people of Austin rather than the cars of Austin. The real problem lies not in the highway’s throughput capacity, but in how it cuts off east-to-west movement and how its frontage roads antagonize the movements of the city by failing in every measure to serve properly as local streets.
Put another way, the problem of the highway isn’t the highway at all, but how it connects, or doesn’t, to the city through which it runs. Above all else, fixing the problem should focus on improving crossings and clearly establishing frontage roads as local streets to promote pedestrian and cyclist participation, comfort and access.
In June of 2015, Senator Kirk Watson’s office announced a plan for a $4.3 billion overhaul for I-35 between Georgetown and San Marcos. This sort of talk may ring a bell for those of you with long memories, given that I-35 improvement plans first surfaced in 1987. Though potentially stymied by recent legislative action rejecting greater use of public-private partnerships for road construction, portions of the plans, dubbed “Mobility35,” are already in various stages of design and construction.
The 26 lanes of Houston’s Katy Freeway. Photo courtesy of the Houston Chronicle.
For Austinites, the Mobility35 Plans are flawed in several measures. They’re entirely predicated upon the belief that new lanes will translate to improved traffic flow. However, the concept of traffic generation — simply put, that more capacity leads to more use — suggests that traffic volume will actually increase in response to new lanes.
The evidence of this phenomenon has been on spectacular display regionally in the form of West Houston’s bloated 26-lane Katy Freeway, a stretch of I-10 that has seen congestion levels spike considerably after its enlargement.
I have myriad other concerns with the plans, which continue their slow but inexorable march over the city and without meaningful engagement of city leadership and staff. But my argument here is in support of the highway’s “other life,” the ecosystem of people living and moving around it — yet another measure in which current plans fail.
The problem in this regard is clear: TxDOT measures the performance of its highway projects through a single metric, “Level of Service,” which is best described as a measure of travel time for vehicles. This myopic focus on capacity is responsible for I-35’s greatest shortcoming: its near stranglehold on movement and access in central Austin. Simply put, I-35 has disconnected us, literally and figuratively, since its construction, and still does today. Instead of Level of Service, we should be measuring the merits of I-35 plans through Level of Access.
Intersections: The Importance of Connectivity
Access is the most sympathetic measurement of mobility success within an urban environment. Measuring access means making design decisions to improve fluidity of movement, ease of connections, comfort and safety for pedestrians, utility for residential neighborhoods, support of all modes of travel, and attending to the needs of users of all ages and abilities. Central to this design is connectivity — simply put, that places connect to each other and can be reasonably accessed by all people. Connectivity as a major driver for equity in access explains why the concept is so baked into the core values of the city’s Imagine Austin Comprehensive Plan.
The construction of I-35 in downtown Austin in 1960. Photo courtesy of the Austin History Center.
Connectivity, however, is systematically hindered through the downtown area by I-35, particularly when compared to other significant parallel streets. From Cesar Chavez Street to 11th Street in front of the State Capitol, for example, Congress Avenue sees seven total functional crossings — counting pairs of one-way streets as a single crossing — in its approximately one-mile run (This does not account for the recent two-way conversion of Fifth Street; this and projects like it could nearly double the total number of functional crossings at Congress Avenue).
Over its parallel run in the same distance, I-35 has only three crossings, less than half the total level of connectivity seen on Congress Avenue. Even Waller Creek and Shoal Creek — legitimate natural barriers — each boast more crossing points than I-35 through downtown.
I-35’s upper and lower decks from around Manor Road. Photo by Smallcurio / Flickr.
I-35 connectivity gets even worse outside of downtown, where its run through the city’s north central first- and second-ring subdivisions sees a total of only five crossings over nearly three and a half miles. Neighborhood subdivisions built prior to I-35 have seen their connections across it severed; ones built in the mid-century were never even connected in the first place. Indeed, the farther north you travel along I-35, the more obvious its impact becomes on the stratification of central and North Austin neighborhoods.
This is important, since the lack of I-35 crossings through downtown and north central means that all pedestrians, transit users, bicyclists, and motorists wishing to cross the interstate corridor are funneled into a very small number of paths to do so — thus encumbering these intersections with disproportionate traffic loads compared to the rest of the street grid. Having a network of streets doesn’t do us much good when we’re only electing to use a handful of those streets, does it?
Unfortunately, current Mobility35 plans do not add any new crossings between 290 and Lady Bird Lake:
Existing/Mobility35 proposed crossings of I-35. Click on the image for a larger view. Graphic by Brendan Wittstruck / Image courtesy of Google Maps.
There are a number of potential solutions to this problem, but the most modest one is to re-evaluate what TxDOT refers to as the “Lowered” option — its former name, the “Depressed” option, must not have polled well — to emphasize creating new connections, rather than merely maintaining the existing ones. This approach would require a selective re-engineering or removal of some on- and off-ramps through downtown, and would double downtown connectivity by re-opening 3rd, 4th, 5th and 15th Streets across I-35. There are clear multimodal benefits to this plan, including enhanced crossings of the MetroRail’s Red Line and the Lance Armstrong Bikeway.
However, adding crossings downtown pales in comparison to the mobility and community value of lowering the highway’s main lanes all the way to 290 and increasing connectivity in north central Austin.
Potential expanded crossings made possible by a lowered I-35. Click on the image for a larger view. Graphic by Brendan Wittstruck / Image courtesy of Google Maps.
In this vision, residents in Cherrywood and Hancock neighborhoods, whose streets once met at the former East Avenue (now I-35), would see east-west access more than triple with the re-introduction of direct connections at 30th, 32nd, Luther/Edgewood and Concordia Streets.
Farther north, neighborhood subdivisions that never connected in the first place would, for the first time, be able to enjoy potential connections such as 45th/Fernwood, 46th/Bentwood, 49th/Barbara Jordan, 52nd and 53rd Streets. In total, a connected vision of I-35 through north central and downtown Austin could realize fifteen or more new connections, each of which would relieve congestion pressure on the few existing, overburdened interchanges.
Frontage Roads: The Highway Next to the Highway
Where the connections across IH35 are key toward the unified, resilient local road network that is needed to ameliorate the city’s access woes, the design of the frontage roads is the key indicator of how the highway’s edges will either support or detract from the quality of life of those living, working and moving along the corridor.
Downtown Austin’s frontage roads are mostly unique for a major Texas city, in that they function in the manner of exurban and rural access roads rather than as part of an urban street grid. When urban interstates were imposed in the mid-century upon more established Texas cities, including Dallas, Houston, and San Antonio, the level of complexity of their introduction into city centers meant that they usually worked in constrained environments, and frontage roads behaved more similarly to non-interstate local streets. Austin, a gangling adolescent in the mid-century era, lacked many of these constraints — evident today in the city’s oversized, vehicle-centric frontage roads.
Traffic on I-35 downtown. Photo courtesy of Wikimedia Commons.
In short, Austin’s frontage roads are a highway next to a highway, and the effect is as predictable as it is tragic. Through central Austin, I-35’s frontage roads have posted speeds between 40 and 45 miles per hour. Statistics show that a pedestrian struck by a motorist at forty miles per hour has only a 10 percent chance of survival; in the same circumstance at thirty miles per hour, that survival chance jumps to 50 percent.
Sadly, a visualization of traffic fatalities in Austin makes the line of I-35 painfully visible:
A map of Austin traffic fatalities in 2015. Click for an interactive view. Image courtesy of Vision Zero ATX.
These numbers don’t even account for the pedestrians not injured because they were never there in the first place. I-35’s frontage roads are an accessibility embarrassment for the city, with a regular rogue’s gallery of incomplete, poorly-maintained, or just plain non-existing sidewalks preventing equitable access along the corridor. TxDOT’s insistence that street trees present dangerous obstacles for drivers — as opposed to critical protection for pedestrians — leaves the corridor barren of the street tree coverage that defines the city’s Great Streets Program and Subchapter E standards for urban roadways.
Existing frontage road accessibility (left) versus the City of Austin’s Great Streets design guidelines (right). Photo by Brendan Wittstruck / Image courtesy of the City of Austin Great Streets Development Program.
This paints a bleak picture of I-35’s frontage roads for any potential users on foot, bike or wheelchair. Discouraging this human-level transport usage then inhibits local business development, creating (or sustaining) empty, unsafe places.
It’s not a friendly-looking place to walk, is it? Photo by Brendan Wittstruck.
The natural aversion of people to such an environment further contributes to the division of neighborhoods, and itself represents additional vehicle miles traveled in situations where many people could walk or bike if they didn’t fear for their lives while doing so — but most importantly, its inhospitable nature is a violation of the inalienable rights of people to move freely and safely.
A vision for I-35 needs to embrace the frontage roads as local roads in their own right, not as auxiliaries to the interstate. Fortunately, Austin has strong existing standards for precisely how to do this, and these standards should be applied to the city’s largest corridor.
The sidewalk design on Cesar Chavez Street downtown shows what the city’s Great Streets Program can do for walkability. Photo courtesy of the City of Austin.
Such a vision must explore policy decisions regarding posted and design speeds, along with human-focused design decisions such as the limiting of free right turns, the narrowing of curb radii, the introduction and maintenance of protected bicycle lanes, shaded pedestrian refuge areas, street trees, green infrastructure and pedestrian-scaled signs and lighting.
Conclusion: It Could Be Worse, But It Must Be Better
Austin’s come close to doing disastrous things in defense against the reality and perception of its connectivity problems in the past. The Austin Transportation Plan, 1962-1982, the local apotheosis of mid-century urban renewal planning, offers a terrifying glimpse of how the planning logic of the time would have had Austin look today:
A map of the Austin Planned Arterial Network, 1962-1982. Image courtesy of TexasFreeway.com.
Our contemporary understanding of mobility recognizes that nearly the entirety of downtown traffic congestion issues arises from “choke points”, including I-35, Lady Bird Lake and Guadalupe Street at Martin Luther King Jr. Boulevard, which all subvert the natural fluidity and resilience of a grid system by channeling it into a handful of overburdened intersections.
Travel time estimates for the existing Austin area in the 1962 transportation study. Doesn’t seem so long, these days. Photo courtesy of the Capital Area Metropolitan Planning Organization.
Now imagine if the 1962-82 Plan — which called for the addition of the Town Lake Expressway along West Cesar Chavez and East Riverside, a grid-busting Crosstown Expressway through the Clarksville and Chestnut neighborhoods, and the Central Expressway, which would have obliterated the Drag — had been realized in its entirely. Things could have been much, much worse.
But they need to be better, and better starts with a vision. Realistically, the proposal for lowering I-35 all the way up to 290 would require vastly more coordination, planning, funding and vision than any of the Mobility35 plans, largely because its design is predicated upon the complete removal of the highway’s upper decks.
The expense of lowering the main lanes, not to mention construction time and impact, would also be far greater than that of a downtown-only plan, owing to the longer distance and less potential return on investment where funding mechanisms like Tax Increment Financing zones or Public Improvement Districts are not economically viable in the foreseeable future.
I-35 under construction over Airport Boulevard, circa the early 1960s. Photo courtesy of the Austin History Center.
But I challenge that any investment in I-35 absolutely must be undertaken with vigor for a vision of a hopeful future, instead of a retreat into doing little for the sake of doing. We will not see I-35 become a better neighbor if we do not dream it first.
Better means that access, rather than throughput, must be the metric of success. An I-35 measured only by Level of Service is diametrically opposed to an I-35 measured by Level of Access. While the latter celebrates the ability of all people to get from place to place through all modes of travel, the former calculates only the speed of cars and the road’s capacity to enable them. Level of Service doesn’t just inhibit Level of Access — it kills it.
This is why the “other life” of I-35 is the conversation we should be having when we talk about the interstate. A vision of I-35 that connects communities, fosters small and large businesses, enables users of all modes and abilities and values the lives, comfort and safety of its neighbors over saving commuters a few seconds on travel time is a vision that encourages the health and well-being of the residents, visitors, and businesses of Austin.
The good news is that we have the design and policy standards necessary to achieve these goals. There is a future for I-35 that is more connected and more welcoming, and when we demand this future, we will get the highway right.
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