
We all know and can understand the benefits and the advantages of limited access roadways, better known as freeways. But, it is the emerging negative impacts that these freeways have on our urban neighborhoods that we are just now beginning to understand.
So how did it all start? The envisioned purpose and need stated in the 1938 Federal-Aid Highway Act was to create a roadway network. A network built to a set of standards that would provide for national defense, as well as to meet the desire and ability of the growing general population to drive longer distances.
After viewing the autobahn, leading highway engineers in the US agreed the German roads were wonderful examples of modern road building, but noted that the network was in predominantly rural areas, serving small amounts of traffic. The engineers were clear that the system in the US would be different, it would be one that served the crowded and congested urban areas. Interregional Freeways, limited to areas where the present and future traffic would justify the infrastructure, these were to be major roadways intended for the purpose of relieving urban traffic congestion.
It was thought from the very beginning by those planning and designing the freeways that these roads would exert a powerful force on the character and development patterns of the urban areas; it was originally thought to be a positive force.
The problem is now clear, the highway engineers that were beginning this task of designing these interregional freeways began with one simple task, relieve congestion. This one-sided planning and design was fuel for the decentralization of urban centers; not the solution it was hoped to be. What was intended to be a regional system of roadways changed with the 1944 Federal-Aid Highway Act and became an interstate system of freeways. The outcome rapidly caused decentralization of the urban centers while the suburban areas grew.
With the Housing Act of 1949, the urban renewal era was given life. During this time it was feared by some that the redevelopment projects would block the corridors needed for these new interregional highways. So the planning and construction of the freeways was expedited, bisecting and isolating existing urban neighborhoods. It’s apparent today that this roadway planning continued to be extremely one sided, planning for the new freeways with a blatant disregard for the existing neighborhoods.

image: Colorado Department of Transportation
Early proponents of the interstate system believed the network of roads was the genie in a bottle, but they soon realized that the genie granted the wish wrong…or maybe it was the person wishing that wasn’t clear. Either way, the situation of our urban areas worsened while engineers and planners continued business as usual, building more and bigger inner city expressways that now connected to interstate freeways hoping to ease congestion and provide the necessary framework for the revitalization of the city centers.
In 1949 with the enactment of the housing bill, various public agencies were separated and given narrowly defined roles, thus collaboration and cooperation between the agencies became strained and in some cases non-existent. For instance, the Federal Housing Administrator was focused on urban “redevelopment” while the Public Roads Administration focused on roads, specifically interstate highways. Yet in an ironic twist they were both planning and designing for the car.
At the same time of this compartmentalization, professionals and non-professionals such as Lewis Mumford and Jane Jacobs were speaking out against the apparent lack of coordination and the emphasis of the car in urban planning and city development. In Mumford’s The City in History and Jacob’s The Death and Life of Great American Cities, both insisted that the way to improve our urban cities wasn’t to limit access and connectivity but rather to increase and improve access and connectivity.
Based on this past knowledge regarding freeways and their impact on urban neighborhoods, it is time for Urban Designers/Landscape Architects to become the leading force for a new connected and accessible urban design model. When roadways fail and need to be updated or replaced, the approach should not be to make them larger. This mindset of urban design and transportation planning has been applied for many years and should be reassessed. We will always need to look at creating efficiency in our roadways, but we should also continuously design for the integration of various roadway systems.
Cities around the world are constantly faced with old infrastructure in need of rebuilding. For example, Denver has the opportunity to reshape its future with a once in a life time project. I-70 East, as it bisects several North Denver neighborhoods, is failing both on a structural and a capacity level. The city has the chance to correct some design and planning mistakes from the past by repairing and revitalizing some of the original neighborhoods in the city. It is now understood that these neighborhoods are in decline, in part, because of the freeway that runs through them.

image: Colorado Department of Transportation
The current solution for I-70 East, supported by community leaders and state engineers, is to take a limited access freeway and restrict neighborhood access even more by depressing it into a trench. The end goal is to place a roof garden over top of a tenth of the sunken roadway to “green” it up. This is an example of a single-focused transportation department single-handedly planning and designing an infrastructure project without the coordination and collaboration of other agencies and departments. This focus should be driven more by urban design and planning rather than the typical ideals of transportation planning shown in this proposal.

image: Keith Billick
There is an alternative solution that has been discarded as outside the project’s purpose and need. It would utilize parallel roadways to offer route options for local and non-local traffic. This dissipation of traffic would allow the removal of I-70 East, replacing it with an at-grade boulevard – a boulevard that would knit back together the fragmented community fabric by connecting sidewalks, bike trails, and roadways.

image: Keith Billick
One measurable impact from a capital improvement project of this type is the short and long term effects to the value of the adjacent residential properties. Public infrastructure should be used to add value to private properties and thereby increasing the “value” of the city as a whole. It has been shown in a variety of studies that increased connectivity and access through mass transit on local roads significantly increase surrounding values, while limited connectivity and access with freeways decreases the value of the surrounding properties.

image: Keith Billick
Value isn’t just measured by the financial means but by the quality of life. There is growing evidence that freeways through residential neighborhoods are extremely detrimental to the resident’s health; both mental and physical. Based on our current pool of knowledge and experience we can do a better job of planning and designing infrastructure so it has positive impacts on our communities. It seems counterproductive to use urban design and transportation planning practices from past decades. If we must plan, design, and build limited access roadways through full access neighborhoods, we must continuously do so without limiting the potential of both.
Additional Information:
reimaginei-70
Unite North Metro Denver
I-70 East Environmental Impact Statement
by Keith Billick, ASLA, Urban Design PPN Officer
This is fascinating. In Boston’s Big Dig, we removed the above ground I-93 road and depressed practically the entire road underground so we could reconnect the North End to the Financial district. I think this has been a success. In Denver, only building over 1/10th of the roadway seems insufficient. Is there a percentage of coverage that would make this project successful at reconnecting neighborhoods? It seems that the freeways need to remain, and depressing them lets that happen, while allowing coverage by new green space.