Locals call it the Mixmaster and often refer to it with colorful phrases invoking four-letter words.
The Interstate Highway 30/Interstate Highway 35E interchange on the western edge of downtown Dallas has been recognized as one of the top 10 worst commuting bottlenecks in the country by the American Automobile Association.
“It’s been a commuting headache for years now,” said Tim Nesbitt, a professional engineer and project manager of the Texas Department of Transportation (TxDOT).
There is hope on the horizon for Dallas-area drivers.
Through Project Pegasus, TxDOT is re-designing the Mixmaster, Lower Stemmons and Canyon sections of the freeway system, with the mission statement of “transforming our downtown freeways.” All told, the billion-dollar project will improve 11 centerline miles of roadway.
The area’s congestion is located on a section of IH 30 south of downtown dubbed “The Canyon,” and the “Lower Stemmons,” which is the local name for the portion of IH 35E from the Mixmaster to State Highway 183.
Commuters traveling the Mixmaster/Canyon routes experience bumper-to-bumper traffic for an average of six hours every weekday. During their morning and evening commutes, drivers crawl along at 20 mph for much of their trip.
In addition to slow speeds and long hours of congestion, highway conditions also result in frequent traffic accidents and increased air pollution.
Nesbitt explained that in the 1950s, when the current highway system was designed, downtown Dallas was “the place to be” — a center for both entertainment and employment. At that time, the objective for highway designers was to get people to downtown Dallas.
Now, four out of five vehicles want to travel around downtown Dallas. Many are headed to the Medical/Market Center area near the upper end of the Stemmons freeway corridor, where approximately 200,000 people are employed at institutions such as the University of Texas Southwestern Medical Center and the Children’s Medical Center.
The population growth in the Dallas-Fort Worth region also has contributed to transportation problems. The Dallas County population has doubled in the past 40 years, and regional experts expect it to double again within the next 20. Traffic on IH 30 and IH 35E has been increasing at the rate of 1 to 5 percent each year.
Despite the increase in usage over the years, no significant changes have been made to improve roadway capacity since the original construction of the freeways. The result, said Nesbitt, is that the current highway system “just doesn’t solve the problems today that it did in 1950.”
The majority of the funding for Project Pegasus will come from the federal government, via the state’s apportioned amount of fuel tax dollars.
“Traditionally, these projects can take 10 to 20 years to be funded,” Nesbitt said. “If we didn’t have federal dollars, we’d be in dire straits trying to get improvements realized.”
Construction costs are budgeted at $975 million, with an additional $30 million planned for right of way costs, mostly to allow for expansion and addition of new ramps. Nesbitt explained that the majority of the right of way acquisitions will be in the retail/commercial/industrial zone of downtown.
Though Project Pegasus is not expected to break ground for three more years, the concept has been in the works for approximately a decade.
It began with the Trinity Parkway Corridor Major Transportation Investment Study (MTIS), which was conducted from 1996 to 1998. The goal of the study was to develop a solution to the problems along the Canyon, Mixmaster and Lower Stemmons corridors.
After considering more than 40 improvement alternatives, MTIS recommended more than $1 billion in multi-modal transportation improvements.
As a result of MTIS, Dallas Area Rapid Transit began planning a light rail extension, running parallel to IH 35E, to serve northwest Dallas. In addition, the North Texas Tollway Authority prepared preliminary engineering plans for a new parkway/reliever route, called the Trinity Parkway.
Once MTIS had made its recommendations, TxDOT was prepared to move forward with re-designing the original, 1950s downtown freeway system. It planned to utilize Intelligent Transportation Systems such as an improved highway advisory system, surveillance cameras, and other modern facilities.
Nesbitt described the MTIS solution as an all-inclusive informational system that will give people more choices: “So they don’t have to keep relying on the antiquated highway system we have today.”
TxDOT proposed major highway re-design elements including adding lanes along IH 30 and IH 35E; improving entrance and exit ramps; constructing a continuous High Occupancy Vehicle system along IH 30 and IH 35E; and adding numerous controlled access frontage roads and collector/distributor roadways.
In 2001, the transportation department launched its formal schematic design and environmental document preparation stage. For the next four years, it would refine the MTIS recommendations through public and agency involvement, preliminary engineering, environmental studies, and urban design/aesthetic studies.
First, TxDOT developed various conceptual alternatives for addressing the problems at hand, weighing factors such as safety, costs, and social, economic and environmental concerns. Then, it presented these alternatives to the public through a series of meetings and community work group gatherings.
Between August 2002 and January 2003, the study team refined the most viable alternatives and held additional public comment sessions, aiming to build consensus for a Locally Preferred Alternative (LPA) for the IH 30 and IH 35E corridors.
As time consuming as it is, as far as Nesbitt is concerned, public involvement is a major key to the success of Project Pegasus.
“If you don’t cover all your bases [in terms of public participation], then in the 11th hour you’ll start to stumble — if you don’t open your doors to brainstorming with the public. You’ll start reaping the benefits in the latter days of the project. That’s your source of pride: when you find out how far you’ve come and how much everyone has bought into the project,” he said.
Based on this public input and other evaluation criteria, one alternative for each highway section was chosen for further development. This development consisted of a design schematic, Environmental Assessment, Interstate Access Justification Report and Design Exception Report.
The design schematics addressed several key concerns: opportunities for urban design, minimizing business and right of way impacts, maximizing weaving areas between ramps, and allowing for improved circulation.
Additional revisions were made to the selected improvement alternatives based on a March 2003 Value Engineering Study, which explored ways of improving project quality, reducing costs, and ensuring efficient investments.
In 2005, Project Pegasus received environmental approval from the Federal Highway Administration (FHWA), meaning that TxDOT was cleared to proceed with project design and right of way acquisition.
As of this November, TxDOT was in the process of assigning detailed construction design. According to Nesbitt, the transportation department was still exploring whether it would distribute the construction design workload internally, or hire external consultants.
The public, sick of tackling the ugly knot of traffic every day, wants TxDOT to move as soon as possible.
“It’s a welcomed project,” said Nesbitt.
Part of the reason that Project Pegasus has been so well received is its emphasis on urban design, which Nesbitt said is a relatively new approach for TxDOT. As he explained, this project has the potential not only to address functionality, but also to take into account the local community’s objectives concerning the downtown region.
“It’s about relating design to its location, by physical setting or cultural values,” Nesbitt added.
When it comes to visually pleasing design, Project Pegasus is off to a great start. The initial urban design plan — created by the architectural/engineering/construction firm Carter & Burgess — received an Award of Excellence from the Texas chapter of the American Society of Landscape Architects. The design was praised for showing how a well-orchestrated urban design strategy can complement adjacent properties and strengthen their relationship to the city as a whole.
The implementation of the urban design plan depends on the city of Dallas and Dallas County agreeing to cost-share with TxDOT on details such as specialty pavement, lighting and bridge structures.
Nesbitt hopes that the various agencies can arrange a partnership that will ensure that Project Pegasus presents its most beautiful face to the world, because he sees this project as a once-in-a-century opportunity.
“What we’re designing today will last for the rest of this century. Whatever we construct out there, however we design it, is going to be caught within those picture postcards they take of the Dallas skyline,” he concluded. CEG
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