RING ROAD RETROFIT

FALL 2018

ARCH + THOUGHT SEMINAR
STUDENTS: IVAN VENTURA + GABRIEL GARCIA
FACULTY: IAN CAINE

1. THE BIG IDEA

San Antonio is in need of an infrastructural retrofit which provides safer pedestrian-oriented means of access.

The unchallenged prioritization of automobile transportation has damaged the livability of San Antonio along its frontage roads. The continuous frontage road and the diamond U-turn intersection are obsolete infrastructures which no longer fulfill the same role for which they were built. San Antonio has rapidly urbanized and pressed itself upon the edges of its highways, and in doing so has outgrown the original context of these infrastructures. Today, San Antonio is in need of an infrastructural retrofit which provides opportunity for new pedestrian oriented means of access, more akin to its urban conditions in the 21st century.

TWO INFRASTRUCTURAL INNOVATIONS FROM THE MID-1900's

Between 1940 and 1967, Dewitt C. Greer, head engineer of the Texas Highway Department established two innovations which to this day remain some of the largest contributions to the way Texans use their cities: the continuous frontage road, relentlessly paralleling all Texas highways in both directions, and the mysteriously unique diamond interchange U-turn, otherwise known as the Texas Turnaround, hugging the underpass and binding the opposing sides of these frontage roads. In the late 20th century, these two superstructures paved the way for the radial growth of San Antonio. An underlying reason for the success of this type of growth was the optimistic presumption that society would ultimately shift toward an auto-centric lifestyle.

THEN + NOW: DENSITY ALONG HIGHWAY INTERSECTIONS

Generally, Texan citizens adopted this predicted lifestyle, using these unique infrastructures to facilitate their commutes and maneuver throughout their rapidly growing cities. However, over 60 years have passed since the dawn of these suburban creations, and the urban realm has significantly changed since. What used to be sparse rural development along the frontage roads has evolved into dense nodal development adjacent to the diamond u-turns, akin to a new urban environment.

The unchallenged prioritization of automobile transportation has left us with segregated barrier developments along frontage roads, spatially disconnected from one another, only accessible by means of automobile. The continuous frontage road and the diamond U-turn are obsolete infrastructures which no longer fulfill the same role for which they were built. The city has rapidly pressed itself upon the edges of these mobility channels, and in doing so has suffocated and congested the auto-centric culture for which they were made. Today, San Antonio is in need of an infrastructural retrofit, which provides opportunity for new pedestrian oriented means of access, more comparable to the existing urban conditions of the 21st century.

2. PROBLEMS

What are the 4 problems with these infrastructures in San Antonio?

The profuse exploitation of these suburban infrastructures has generated four major problems for San Antonio, threatening the livability of the city. The living conditions along these monolithic automotive bands are inaccessible, unsafe, segregating, and obsolete. 

Where are these problems occurring spatially?

3. SITE

Which highway is best for data analysis?

LOOP 410

Loop 410 is selected for three reasons. Firstly, it contains the largest number of U-turn intersections out of the 7 highways systems, providing more reliable data when quantified as a whole. Secondly, it is a ring-road typology, as opposed to an arterial channel (such as I-10, 281, and I-35), making each U-turn intersection data more comparable to each other. Its proximity to the urban core, as well as its historical significance in the post-war suburban era perpetuates its obsolescence. Lastly, Loop 410 is the inner most ring-road in San Antonio,  demonstrating a historic chronology of suburban development which may hint at a similar future along other ring-roads.

4. QUANTIFICATION

Which intersection has the most potential as a case study for retrofit?

The three metrics which are taken into consideration are pedestrian accessibility by foot, pedestrian accessibility by transit, and pedestrian safety. Data on access was gathered by transposing the accredited Walk-Score on each intersection, and visualizing this information spatially. Gathering data on pedestrian safety was a more rigorous process. This data was gathered by requesting pedestrian accident data charts from the Texas Department of Transportation and extracting number of accidents/intersection/year on the 32 intersections above. Based on these numbers, a percentage was given to each intersection relative to each other.

5. SELECTION

Blanco Road is selected for retrofit.

Blanco Road shows the most promise as a retrofit because it ranked highest in access, followed closely by Fredericksburg and Broadway. Additionally, other intersections along Loop 410 are much safer than Blanco Road , such as Honey Suckle, Palo Alto Road, and Harry Wurzbach. This suggests high activity with risk of pedestrian accidents on Blanco and Loop 410. This calls for a retrofit.

6. RETROFIT

PLAN, BLANCO ROAD, EXISTING
SECTIONS, BLANCO ROAD, EXISITNG