FHWA Carbon Sequestration Pilot Program Results

Washington, DC (June 3, 2010)- The U.S. Federal Highway Administration’s Office of Planning, Environment, and Reality has released a report that explores whether a roadside carbon sequestration effort through modified maintenance and management practices is appropriate and feasible for state departments of transportation (DOTs) when balanced against ecological and economic uncertainties.


The report examines the amount of revenue that DOTs might earn if they undertook a carbon sequestration effort using native vegetation and the cost-effectiveness of a similar effort on a national scale. The report also highlights decision support tools that DOTs could use to help determine the efficacy of programs in their states.
The Federal Highway Administration (FHWA) established the Carbon Sequestration Pilot Program (CSPP) in 2008 to assess whether a roadside carbon sequestration effort through modified maintenance and management practices is appropriate and feasible for state Departments of Transportation (DOTs) when balanced against ecological and economic uncertainties. The purposes of the pilot were to:
* Develop estimates of the amount of revenue that DOTs could earn if they undertook a carbon sequestration effort using native vegetation;
* Determine the cost-effectiveness of a similar effort on a national scale; and,
* Create decision support tools that DOTs could use to determine the efficacy of programs in their states.
CSPP findings are expected to inform DOTs that may be considering the implications of future climate change legislation or that independently want to evaluate the cost effectiveness of using National Highway System (NHS) right of way (ROW) to generate revenue from the sale of carbon credits, offset their own emissions, or meet statewide greenhouse gas emissions objectives.
The project team used data from Minnesota and several other states to estimate the amount of unpaved NHS ROW available for carbon sequestration-marking the first time that a rigorous study has been conducted to quantify the amount of state DOT-managed soft estate acreage. In the first of two analytical approaches used, ROW widths at random locations in nine states were manually measured on property maps to provide a distribution of common ROW dimensions and observed vegetation types. A subsequent geographic information system (GIS) analysis of 1,000 random locations nationwide provided insight into the types of land cover in close proximity to the NHS.
Results indicate that there are approximately 5.05 million acres in the NHS nationwide, with a likely range of 1.4 to 8.7 million acres. Roughly 68 percent, or 3.4 million acres, is unpaved. Evidence shows that the land cover has undergone little change since 1992.
The project team estimates the NHS ROW has approximately 91 million metric tons (MMT) of carbon currently sequestered in vegetation and is currently sequestering approximately 3.6 MMT of carbon per year, or 1.06 metric tons of carbon per acre per year. This equals the annual carbon dioxide emissions of approximately 2.6 million passenger cars. At its carbon equilibrium, the entire NHS ROW is estimated to be able to sequester between 425 and 680 MMT of carbon. Using a hypothetical carbon price of $20 per metric ton, this equates to a total potential value of $8.5 to $14 billion nationwide.
The availability of ROW property data was highly variable and, thus, was the major limiter in making these estimates. As discovered through this research, very few DOTs have had time, funding, or impetus to scan and geospatially reference their ROW property maps. The research here could have been vastly expedited had there been more DOTs with property maps in the needed electronic format and had their ROW data been easily accessible in a national GIS database.
In addition to this report, FHWA has developed a Highway Carbon Sequestration Estimator to help DOTs assess the return on investment for various carbon sequestration scenarios. The decision-support tool, which allows transportation officials to make estimates based on more state-specific considerations than possible here, is available upon request from carson.poe@dot.gov.
Even under the best scenarios, revenue generated from biological carbon sequestration will vary greatly from state to state based on carbon prices, management techniques, and ecological variability. However, considering the use of vegetation for living snow fences, landslide minimization, and other such human infrastructure protection may, in some cases, eventually be found to be more cost-effective than traditional engineering solutions, especially when all costs are included.
Related Resource:
Carbon Sequestration Pilot Program Results
Tapping Carbon Markets for Urban Forests