The FHWA 2015 R&T Story

Promoting Environmental Sustainability

Workers use a high-pressure jet wash and truck-mounted vacuum to remove debris from existing pipes as part of preparations for the FHWA-supported culvert reconstruction project conducted by Montana DOT using trenchless technologies. Half of the corrugated steel pipe culverts would be lined (sliplined) with high-density polyethylene pipe and half would be lined with cured-in-place pipe.

Examples of FHWA research and innovation delivery activities: Promoting Roadside Revegetation: An Integrated Approach to Establishing Native Plants Using Renewable, Reusable, and Recycled Materials to Achieve a More Durable Highway Infrastructure Developing Innovative Tools to Assess Environmental Impacts Integrating Sustainability into Transportation Projects

FHWA supported a new construction project with Georgia DOT. A solar-powered trailer and traffic sensor were used as part of the system. (Images: FHWA)

The benefits of environmentally friendly transportation networks extend beyond the highway system.

Surface transportation significantly impacts the environment. Motor vehicles are responsible for 23 percent of greenhouse gas emissions in the U.S.,¹⁸ and while essential to supporting mobility and economic growth, traditional highway designs sometimes disrupt critical wildlife habitats. Each year, deer-to-vehicle collisions alone lead to approximately 200 human deaths and $1.1 billion in property damage.¹⁹

FHWA is a leader in developing new technologies and improved practices that minimize negative impacts on people, the environment, and natural resources. FHWA provides tools, technical assistance, proven processes, and data so State and local agencies can perform effective environmental planning. FHWA also supports transportation agencies’ efforts to protect natural spaces and resources that are vital to the health of the Nation’s wildlife.

Research Activities

Examples of FHWA R&T that support the environment include finding effective ways to grow native plants following a highway construction project, establishing policy that supports the use of recycled materials in construction, and developing online tools to integrate environmental considerations into standard business practices.

Promoting Roadside Revegetation: An Integrated Approach to Establishing Native Plants

Today, most road projects involve modifications to existing roads rather than new construction. Execution of such projects in a safe and effective way while maintaining ecological health is a critical component of success. Modifying roads or updating them section by section also presents a tremendous opportunity to remedy the oversights of the past, mitigate environmental impacts, and improve the health of affected ecosystems. Making the environment an important consideration for transportation improvements requires standardized guidance and a framework for collaboration across and among stakeholders.

FHWA streamlines federal land management and Tribal processes to improve timeliness and effectiveness of program and project delivery. Through its Coordinated Technology Implementation Program, FHWA worked with the U.S. Forest Service to develop a comprehensive roadside revegetation technical guide, which offers an integrated approach to facilitate the successful establishment of native plants along roadsides and other areas of disturbance associated with road modifications.

The guide introduces a comprehensive process of initiating, planning, implementing, and monitoring a roadside revegetation project with native plants. The partnership also resulted in a Web site, at http://www.nativerevegetation.org/, which contains integrated and interlinked modules dedicated to explaining the art and science of roadside revegetation.

Currently, FHWA’s Western Federal Lands Highway Division uses native vegetation in all of its construction projects. Both the National Park Service and the U.S. Forest Service have vigorous revegetation programs in place. Glacier National Park operates its own nursery to grow native plants for revegetation of disturbed areas. In addition, Oregon, Washington, and California State DOTs use native plants in many of their highway construction projects.

Vegetation Management: An Ecoregional Approach is a recent example of FHWA’s commitment to cost-effective sustainability. FHWA encourages State land managers to adopt an ecoregional approach to better manage roadside vegetation, and the guide provides practical advice to help them accomplish this. The examples and instructions found in the guide make clear that, by using native plants in highway projects, States can save fuel and other maintenance costs while reducing their environmental impact. State DOTs have received copies of the guidebook, and an e-book version will be available in 2015.

Using Renewable, Reusable, and Recycled Materials to Achieve a More Durable Highway Infrastructure

FHWA is advancing the effective use of renewable, reusable, and recycled materials to reduce the cost of transportation projects and ease the effects of transportation construction on the environment. For example, use of reclaimed asphalt pavement (RAP) in pavement mixtures has been turning what might otherwise be sent to a landfill as waste material into a resource for more than 30 years. However, currently available guidance has proven inadequate to ensure that pavements built with RAP will be durable. FHWA has built and is currently testing full-scale pavements that contain specific levels of RAP to assess its performance. When completed, this research will deliver guidance to help highway agencies and their contractors achieve durable pavements when using RAP.

Building on the research findings from FHWA and the knowledge-sharing provided by FHWA’s Sustainable Pavement Technical Working Group, numerous States are currently using recycled construction materials to save on costs and free up funds for additional highway construction, maintenance, and repair. For example, using recycled materials is commonplace on New York State Department of Transportation (NYSDOT) projects. Recycled materials allowed directly in the NYS- DOT standard specifications include RAP, recycled concrete aggregate, beverage container glass, blast furnace slag, and coal fly ash, among others. Other recycled materials are evaluated on a case-by-case basis. For instance, average RAP in asphalt mixes is estimated to be around 15 to 20 percent and recycled concrete is the predominant granular material used in the metro New York Area. Additionally, when concrete is removed from pavements and structures, any reinforcing is typically removed and recycled, and the concrete often becomes fill material somewhere else on the project to flatten slopes and is occasionally used as filter material. The Department’s sustainability program, GreenLITES, has also contributed to the increased use of recycled and reused materials and greatly contributes to NYSDOT’s supporting a sustainable society.

Developing Innovative Tools to Assess Environmental Impacts

The National Environmental Policy Act of 1969 (NEPA) requires both the assessment of environmental impacts of federal activities and the planning of any needed mitigation to lessen or eliminate damage from construction activities. As part of its commitment to NEPA, FHWA requires the examination and avoidance of potential impacts to the social and natural environment when considering approval of proposed transportation projects. FHWA also incorporates into this process a NEPA-mandated interdisciplinary approach in planning and decisionmaking for any action that adversely impacts the environment. Transportation agencies need tools that facilitate collaboration across transportation, regulatory, and special-interest organizations to plan and deliver projects as quickly and efficiently as possible.

As part of its objective to promote more informed transportation decisionmaking, FHWA developed an online tool called e-NEPA to help practitioners streamline the NEPA process. e-NEPA is a real-time electronic collaboration tool that allows State DOTs to share documents, track comments, schedule tasks with participating agencies, and perform concurrent reviews of their environmental impact statements and environmental assessments. Currently, States are piloting the tool on a number of environmental impact statement and environmental assessment projects to determine impacts and success factors.

Integrating Sustainability into Transportation Projects

As environmental impacts play an increasingly important role in highway planning, transportation agencies need tools to integrate environmental considerations into their policies, processes, procedures, practices, and projects.

As part of its commitment to promote integrated planning that improves transportation safety and addresses environmental, social, and economic needs, FHWA developed the Infrastructure Voluntary Evaluation Sustainability Tool (INVEST). Available at www.sustainablehighways.org, INVEST is being used by 29 agencies in 25 States and Washington, DC including DOTs, MPOs, councils of government, and public works departments. Other partners use INVEST to evaluate and integrate sustainability into their programs and projects.

Newly reconstructed and environmentally sensitive business-tourist corridor with new vehicle lanes, pedestrian pathways, and structural retaining walls, developed as part of an FHWA project. (Image source: FHWA)

The FHWA Eastern Federal Lands Highway Division (EFL) used concepts from INVEST’s Project Development (PD) module in their Construction Winter Training Program. The goal of this training was to increase awareness and facilitate greater discussion about sustainability, and to further integrate sustainability considerations into project planning, design, and construction. Using INVEST, EFL found that the Mulligan Road project, located in Fairfax Country, Virginia, excelled in criteria related to context sensitivity, pedestrian and bicycle access, ecological connectivity, long-life pavement, environmental training, and construction quality control. Other criteria identified as potential areas for improvement with relatively low additional effort included site vegetation, reducing and reusing materials, and construction waste management.

INVEST has helped show EFL staff the benefits of integrating sustainable practices.

The Illinois Tollway Authority used INVEST to complete an 18-project retrospective evaluation that will set baselines and minimize environmental impacts of new roadway construction by reusing and recycling materials, reducing energy costs, and measuring sustainability of practices. Illinois Tollway will incorporate the INVEST tool into the planning, development, and operations lifecycle of the 15-year, $12 billion Move Illinois Program. INVEST will allow the agency to identify institutional and other barriers that may prevent it from implementing sustainable practices during the construction phase.

Similarly, Ohio DOT used the INVEST PD module during the reconstruction of the Cleveland Innerbelt Bridge/I-90, also known as the George V. Voinovich Bridge. It was critical for Ohio DOT to achieve sustainability for this high-priority project, and the agency focused on major savings in fuel, steel, water, and waste. INVEST was so successful in helping Ohio DOT realize these savings in Phase 1 of the project, it was used to ensure contractor performance during Phase 2. By requiring INVEST as part of the Request for Proposals for the design-build contract, Ohio DOT gave contract bidders a strong incentive to include sustainability practices as part of their proposals while also keeping costs competitive.

The Massachusetts DOT used the INVEST PD module to evaluate the Casey Arborway Project, which could replace a 1950s-era elevated highway with an at-grade roadway with strong pedestrian connectivity. Arizona DOT (ADOT) is using INVEST’s PD module to conduct an assessment of its statewide roundabout program. Particular criteria that Arizona plans to examine further include: green infrastructure and low-impact development, bike and pedestrian mobility, and context-sensitive solutions. Arizona found that INVEST helped ADOT further internal lines of communication, sparking new types of discussion and collaboration.

Leading the Way to More Environmentally Sustainable Highways

The safety, long-term economic viability, and continued operation of the highway system and well-being of its users are affected by environmental factors. FHWA R&T focuses on environmental sustainability as a key challenge because motor vehicles are a significant source of greenhouse gas emissions and roadway construction can adversely affect wildlife habitats.

Environmental sustainability is based on the principle that everything needed for peoples’ survival and well-being depends, either directly or indirectly, on the natural environment. Sustainability creates and maintains the conditions under which humans and the natural world can exist in productive harmony, allowing the fulfillment of social, economic, and other requirements of present and future generations. Sustainability is essential for making sure the Nation has and will continue to have water, raw materials, and resources to protect human health and the environment.²⁰ FHWA’s strategic approach to R&T comprehensively addresses environmental sustainability, and seeks new ways to increase efficiency and collaboration while decreasing impacts to the natural environment and wildlife.

For More Information

The following Web sites are provided for additional information, and further highlight the transportation challenges and FHWA activities discussed above.

Road Revegetation: An Integrated Approach to Establishing Native Plants: http://www.nativerevegetation.org/.

FHWA Recycling Policy: https://www.fhwa.dot.gov/pavement/recycling/.

FHWA Environmental Review Toolkit: http://www.environment.fhwa.dot.gov/index.asp.

FHWA INVEST Version 1.0: https://www.sustainablehighways.org/.

¹⁸ Federal Highway Administration (2007). Roadside Revegetation: An Integrated Approach to Establishing Native Plants. Washington, DC. Accessed online: February 18, 2015. (https://www.wfl.fhwa.dot.gov/programs/td/publications/documents/reveg-documents/roadside-revegetation-manual.pdf)

¹⁹ Mastro, Lauren L.; Conover, Michael R.; and Frey, S. Nicole. (2008). “Deer–Vehicle Collision Prevention Techniques.” Human–Wildlife Interactions.

²⁰ United States Environmental Protection Agency (2015). “What is Sustainability?” (Web page) Washington, DC. Accessed online: February 18, 2015. (http://www.epa.gov/sustainability/basicinfo.htm)