A key consideration that needs to be a part of the planning of the highways we continue to develop, upgrade and expand is the role they play in the sustainability of our communities. But what does sustainability entail and how can it be achieved?

Canada’s Centre for Sustainable Transportation defines a sustainable transportation system as one that:

• Allows the basic access needs of individuals and societies to be met safely and in a manner consistent with human and ecosystem health, and with equity within and between generations
• Is affordable, operates efficiently, offers choice of transport mode, and supports a vibrant economy
• Limits emissions and waste within the planet’s ability to absorb them, minimizes consumption of non-renewable resources, reuses and recycles its components, and minimizes the use of land and the production of noise.”

The potential role of highway enhancements is explored in this article as they might relate to the development, construction, operation and maintenance of sustainable highways.

Sustainable Highways: Enhancements

Highway enhancements have been associated traditionally with features such as sidewalks, bicycle trails, artwork, landscaping and a variety of aesthetic treatments that add value and quality-of-life elements to an otherwise functionally driven project delivery. This view represents some degree of progress, but is fairly narrow and minimal. Often, these traditional enhancements have been either an alternative treatment of a basic project element (e.g., colored concrete) or an afterthought that has been implemented to try to satisfy an isolated environmental commitment that is not truly integrated into the project.

While there are benefits to be gained from these traditional enhancements, they often represent a missed opportunity to develop an enhancement plan from project inception. Earlier planning enables a larger array and a greater variety of options to be considered for improving the highway corridor in the broadest possible sense. Consistent with the concepts of environmental stewardship and sustainability, such planning might well be a core element of the development process that addresses the key concerns and characteristics of the immediate area and the region through which the highway facility passes.

Implementing this philosophy would require, in most instances, a change in the traditional project development process that has been characterized by the dichotomy of different approaches that so often exists between engineers and planners/environmental specialists. Instead, a collaborative and synergetic approach that builds on the ideas and talents of both engineers and planners needs to be adopted.

A Case Study: U.S. 70 in Hondo Valley, New Mexico

The U.S. 70 Hondo Valley project is an example of a project in which this simultaneously broader and more integrated approach was taken in the development phase. It entails the widening and improvement of a 70-km (37.5 mile) -long stretch between Riverside and Ruidoso Downs undertaken for the New Mexico Department of Transportation (NMDOT). U.S. 70 was experiencing a large growth in through traffic, especially heavy commercial traffic, along with high accident and fatality rates. In fact, there had been more than 29 fatalities over a 3-year period.

Within the study limits, U.S. 70 is a two-lane highway that serves local, intrastate and interstate traffic. It passes through a steep-walled river valley with most of the existing highway cut into the base of steep hills. This segment includes numerous sharp horizontal and vertical curve sections, and many intersections with side roads and driveways.

The highway parallels the Rio Ruidoso and Rio Hondo (rivers) and includes irrigated farmlands and riparian habitat for most of its length through the Hondo Valley. The Hondo Valley is home to several small communities in which many extended and multi-generational families reside. These agriculture-based communities are rich in history and tradition. Seasonal fruit stands lining the highway are common, and they help to support the local economy.

The initial phase identified various alternatives that included improving the existing highway or improving other highways and creating a bypass around Hondo Valley. The conclusion was that improving the existing highway was the best way to deal with the traffic growth, safety problems, and the economic development goals of the major communities within southeast New Mexico.

The second phase included a detailed evaluation of concepts to improve U.S. 70. Traffic and safety issues could have been solved easily by the construction of divided multi-lane highway, but such a facility did nothing to preserve the local community and its traditions—needs that became an important cornerstone of all viable alternatives. Our evaluation, which focused on finding a sustainable solution, included:

• Analysis of the conditions that affected safety on the existing highway
• Development of concepts that would correct the identified safety problems and improve local access and travel
• Development of options to address the mix of local traffic and heavy through commercial and tourist traffic
• Creation of enhancements that would help to solidify and preserve the unique character of the Hondo Valley communities
• Analysis of the effects that the improvement concepts/options would have on nearby residents, businesses, and other resources.

Throughout this process, we spent considerable time meeting with people in the community. We conducted several community open houses and individual meetings with property and business owners, giving all stakeholders numerous opportunities to provide feedback that influenced the design of the roadway.

An integrated team of engineers, planners and environmental specialists worked hand in hand throughout the project to develop a solution that best improved the conditions and enhanced the sustainability of the local communities that U.S. 70 passed through. The final recommendation was for a four-lane facility with a number of enhancements, including:

• Intelligent transportation system technologies for speed detection and message boards to inform motorists of their speed
• Parking areas for fruit stands that did not rely on highway right-of-way
• A secondary access to Hondo High School with improved circulation and access to U.S. 70.
• Bus pullouts for school children pick-up and drop-off locations
• Driveway consolidation and grade improvements
• Community entrance signs and landscaping
• Tree replacement throughout the corridor to mitigate the effects of vegetation loss due to the widening
• Provision for emergency medical service during construction with the medical equipment being turned over to the local authorities for use after completion of construction.

The basic highway design needed to minimize land acquisition yet be sufficient to accommodate both the fast-paced commercial traffic that passes through the Hondo Valley and the more traditional local traffic patterns, such as neighbors and family traveling to visit or care for each other, or daily short trips to the local post office. The resulting design provided a four-lane section, with the center lanes serving mostly trucks and faster through traffic and the outside lanes serving mostly local traffic. Left turn lanes designed at the larger intersections maintain the roadway’s flexibility and provide safe conditions for turning traffic.

Conclusions

Having a project need that included sustainability of the existing local communities was key in the development of this project. Early concepts for the corridor had looked at interstate-type options that matched improvements to US 70 outside of the Hondo Valley. Such concepts would have required two to three times the right of way and would have destroyed many of the qualities of the Valley communities. Thus, allowing planners and engineers to work hand in hand through the project development aided in developing a project that met the engineering requirements and helped to improve and provide for the sustainability of the traditional communities in the project limits.

At the time of writing, the project was under construction and scheduled to be completed in the Spring of 2005. Many of the enhancements were already in place. The basic earthwork and slopes were constructed with minimal acquisition of right-of-way. Driveways were improved, a secondary access to the Hondo High School was complete, speed control devices were implemented, and the project is being well accepted by all stakeholders.