The Case For Not Building More Highways, A Manifesto For A Better City

This is a part of a package of articles on the future of transportation in Louisville. For more, click here.

It appears that the Louisville area may be entering a new golden age of highway construction and expansion.

Earlier this year, the Kentucky Transportation Cabinet unveiled I-Move Kentucky, a four-year, $180-million project that would add new travel lanes to sections of Interstate  265 and Interstate 71 while also reconfiguring several interchanges. Simultaneously, KYTC is conducting a $2-million study to determine the feasibility of creating a “regional highway connector” that would skirt the eastern fringe of Louisville between  Interstate 65 in Bullitt County to  Interstate 71 in Henry or Oldham counties.

All this after the paint has barely had time to dry on the Ohio River Bridges Project, which cost more than $2 billion.

Such an aggressive construction program is unusual for a midsized American city such as Louisville, because it bucks a trend growing in many parts of the United States: tearing down highways, not building them. From major cities such as San Francisco and Seattle to smaller urban centers including Rochester, New Haven and Milwaukee, communities are reducing roads once hailed as the pinnacle of 20th-century progress into concrete dust and memories. To be fair, many of the highways being torn down were built during the postwar suburban boom, and their advanced age had created maintenance costs that increasingly outweighed any benefits. But instead of simply being replaced with another, modernized highway, each road in question is making way for street-level boulevards, featuring bike and transit lanes and lined with trees, sidewalks and new urban-style development. This represents a radical change in how communities are thinking about elevated freeways and highways and transportation priorities in general.

But Louisville and the Kentucky Transportation Cabinet do not appear to be interested in joining them, choosing instead to keep doing more of the same. As part of their announcement of I-Move Kentucky, KYTC officials stated that the project would “add capacity, increase safety and improve economic development and quality of life.” This statement nicely summarizes the basic rationale that has governed transportation policy and highway construction in the Louisville area for the last 70 years.

What if that way of thinking is wrong?

What if the basic assumption behind the creation and growth of Louisville’s highways has turned out to be misguided?

What if a different approach to tackling transportation issues in Louisville was needed?

In the paragraphs to follow, we will explore some of the growing body of evidence showing that adding capacity to highways is a counterproductive solution and how a mixture of reforms to both transportation and land use policies will not only have a positive impact on local congestion issues but also make Louisville a healthier, more resilient and more livable community.

So why is building and expanding highways a bad bet?

It has been, after all, the modus operandi of transportation planners and engineers since before World War II. During the explosion of postwar suburban construction, highways were seen as a way for liberating Americans from dirty, crowded inner cities and giving them the freedom to seek out their slice of the American Dream.

Today, supporters of building more and larger roads will argue that they are a powerful economic development tool; they open up previously inaccessible land to be developed into homes, shops and businesses that can all attract new residents, jobs and tax revenue to communities that are often in desperate need of all three.

Also, as that growth increases traffic volumes, investments in highway infrastructure become necessary to alleviate congestion and to improve safety.

While the attractiveness of those benefits is certainly understandable, the experience of the last few decades has caused the once venerable highway to lose some of its luster. If a highway is routed through an urban neighborhood or downtown, it is done at the expense of the surrounding neighborhoods; expanding them usually requires the demolition of abutting homes and businesses, which can cause a severe disruption to the impacted community. Living near a highway can also create significant health impacts for adjacent residents; particulate and other pollutants emitted from vehicle tail pipes have shown to increase respiratory illnesses and even lower property values. In rural areas, building new or expanding existing roads can have significant environmental impacts by creating deadly barriers to wildlife and increasing polluted stormwater runoff into nearby water bodies.

These are all drawbacks that are fairly well known, but there is a more indirect downside to supporting highway infrastructure: the type of land use it encourages. While it is certainly true that building and expanding roads can attract new development, the type of development it brings is an important distinction. Not surprisingly, this type of infrastructure investment is followed by auto-oriented, low-density, single-use development; the mix of strip malls, subdivisions and office parks often given the lackluster label of “suburban sprawl.” The environmental and health impacts of this development pattern have been debated for years, but a growing body of evidence is beginning to show that it is also a poor long-term financial investment. One study in Nova Scotia, Canada showed it costs almost twice as much for a city government to supply suburban-style development with needed infrastructure and services, as opposed to denser, more urban areas. Another study compared a classic downtown building in Charlotte, North Carolina with a typical big box Wal-Mart: It found that the older, urban building housed substantially more jobs and contributed more tax revenue to city coffers (on a per acre basis) than the newer, suburban one.

The style of development encouraged by highway construction costs more for a locality to support with essential services and gives it far less bang for their buck in return.

So, if building and expanding highways have so many documented downsides, why do we continue to build them?

The short answer is: inertia.

The state and federal apparatus that finances, builds and maintains highways is vast and has been well established for decades, and it takes a lot of effort to overcome any resistance to change. But a longer answer involves the explanation of the concept of induced demand.

Induced demand is an economic term that is defined as a phenomenon that causes more of a good to be consumed as the supply is increased; in other words, the more there is of something, the more people use it. The urban planning field uses it almost exclusively to explain the seemingly exponential growth of highways in the U.S. In this context, induced demand works like this: A highway becomes congested, thereby lengthening travel times and discouraging drivers to use it. So, the local transportation authority adds lanes to increase the roads’ capacity; this initially has the effect of reducing congestion and shortening travel times. However, by becoming uncongested, that highway becomes an attractive route to drivers again, so traffic increases until the extra capacity is filled.

The concept of induced demand is a sort of negative feedback loop; the more roadway capacity is added, the more people are encouraged to drive until that capacity is filled, thereby creating the need for even larger roadways. This phenomenon ensures that adding capacity to highways will never actually solve the problem of traffic congestion but merely perpetuates it.

One study of a $2.8-billion expansion of Interstate 10 in Houston, Texas, found that travel times on the roadway had actually gotten worse after the project was completed. The massive infrastructure project widened the “Katy” (as its locally known) to a staggering 23 lanes, making it one of the widest highways in the world; yet from 2011 to 2014, afternoon commutes actually went up by about 55%. How long before Texas taxpayers will have to pay to widen the massive highway again?

If the never-ending cycle of demand-inducing highway construction is clearly not the right way to meet Louisville’s transportation needs, how does the city escape it? What is a better, more productive use of our precious transportation dollars?

Creating a better transportation policy requires all of us, citizens and government leaders alike, to adopt a completely new mindset. Traditionally, the fundamental problem to be solved has been identified as there being not enough space for the number of cars on the road; the solution therefore has to be creating more space for cars to use. But private and public stakeholders need to realize that the fundamental problem is, instead, that there are too many private vehicles using the available road space. In this context, the solution then becomes finding ways to reduce the number of vehicles using the road; to make more efficient use of the travel space that already exists.

Reducing the number of Single Occupancy Vehicles, or SOVs, using local highways can be accomplished mainly in two ways. The first may seem a little indirect: reforming land use policy and development regulations. Since World War II, new development has been shaped and regulated by standardized zoning codes. These “Euclidean” zoning ordinances operate on the principle of separating land uses that are deemed to be incompatible with one another; single family homes go in one district, apartment buildings go in another, shops or offices in yet another and so on. At the time of their creation, these codes were thought of as an antidote to the overcrowded, chaotic trauma of 19th-century industrial cities. But, in practice, they had the effect of forcing new development to be spread out over large areas; eventually to such an extent that driving was the only practical means to get between your house and work and to the store. In short, we built environments that required and, in effect, created total dependency on cars for personal transportation.

If the overall goal is to reduce the number of cars using local highways, Louisville has to start reforming the way new development is built and work to create opportunities to rebuild existing developed sites. City codes and ordinances must be changed to encourage new residential developments to be built in closer proximity to shops and offices and to include a greater mix of housing types. This would allow citizens to take shorter trips to access jobs or go to the grocery store.

Why get stuck in traffic on Interstate 264 or 65 if what you need is right around the corner? Additionally, by making more efficient use of land around existing infrastructure and services, Louisville could serve more of its citizens at a lower cost. By encouraging the redevelopment of existing sites into denser, more mixed-use communities, the city would increase the fiscal and economic productivity of existing real estate.

The other major way to reduce the burden on local highway infrastructure is one that has been discussed substantially in Louisville: getting people out of their cars and using other transportation modes. While encouraging people to walk, bike or take public transit has many health and environmental benefits, it’s also a great space saver. In his book “Happy City,” Charles Montgomery accurately describes cars as “space hogs” — even the smallest vehicles take up at least 150 square feet of space. If the driver of that car were to instead ride a bike or take a seat on a bus, they would occupy only 20 square feet. Cars simply take up a lot more space than other modes.

This speaks to another way that the thinking behind transportation infrastructure planning and investment needs to change. The modus operandi for highway planning has always been finding ways to move as many vehicles as possible. But if we want to use existing road space as efficiently as possible, we have to start finding ways to move as many people as possible. By reducing space for SOVs in favor of other transportation modes that can carry more people, we can increase the capacity of local roads without having to expand their physical footprint.

The scale of these needed changes can be overwhelming, and it may seem hard to find a place to start; but there are several policies that Louisville and KYTC can enact that are fairly straightforward.

The first is to reprioritize the proper maintenance of existing roads and infrastructure over the construction of new ones. Commonly known as “Fix-it First,” this strategy is a more fiscally responsible approach to infrastructure spending, which ensures that existing roads are properly maintained and upgraded before tax dollars are dedicated toward any new major projects. We must also continue the vital work of looking for opportunities to make space for alternative modes of transportation. Road space across Louisville is ripe for conversion into bike lanes and bus-only lanes that can increase the carrying capacity of existing roads. This can often be done simply by restriping the road to include new lane types, which is relatively inexpensive and can be efficiently integrated into regularly scheduled repaving projects.

Finally, citizens, planners and city leaders need to begin the process of identifying parts of Louisville that can be rezoned for higher densities and a greater mix of land uses; examples include the locations of dying malls, vacant industrial sites or other areas that could function as a new “town center.”

At the time of this writing, the I-Move Kentucky Project has already entered the design phase, meaning that it is likely too late to alter its scope or encourage KYTC to integrate any of the ideas discussed here. However, this does not mean that we should stop working to create long-term change in how both state and metro agencies spend precious transportation dollars. It’s a conversation that we as a city need to have, because it will play a huge role in shaping what kind of city we want to be in the 21st century. We need to decide between two futures: one that looks fairly similar to today, with continued investments in expanding highway infrastructure that attracts more low-density, suburban-style development; or the other that begins to balance automobiles with investments in bicycle, walking and public transit infrastructure and introduces changes to land use policies that encourage denser, mixed-use development in both urban and suburban areas.

A growing body of evidence is showing that the status quo will continue to make our city more environmentally, fiscally and economically unsustainable. But the other future, the one where we as a community chose to do things differently, will create a healthier, more vibrant, more resilient city that gives its citizens a wide variety of living and transportation options to choose from.

That is a future that will set Louisville apart and allow it to truly thrive in the years to come. •

Porter Stevens, a native Louisvillian with a masters degree from UofL’s Urban Planning Program, works as an urban planner in Pennsylvania but remains passionate about urban planning issues in his hometown.