In 2013, the pioneering research of James Galloway, University of Virginia’s Sidman Poole Professor of Environmental Sciences, and then-graduate student Allison Leach led UVA’s Board of Visitors to approve a plan to reduce the emissions of reactive nitrogen from campus activities 25 percent by 2025.

In the four years that followed, UVA has gone from being the first university in the world to calculate its “nitrogen footprint” to organizing a network of 20 higher education institutions in the United States and abroad, measuring and attempting to reduce their output of reactive nitrogen that creates smog, acidifies water sources and weakens the upper-atmospheric ozone layer.

“UVA prides itself with being first in many categories, and in being the first university in the world to develop this nitrogen footprint tool, UVA is playing a significant leadership role with respect to the stewardship of the environment,” Galloway said.

UVA and seven other institutions launched the Nitrogen Footprint Tool Network, sponsored by the Environmental Protection Agency’s Sustainable and Healthy Communities Research Program. The work is highlighted in the April special issue of “Sustainability: The Journal of Record.” Published in collaboration with the Association for the Advancement of Sustainability in Higher Education and edited by Leach and Nitrogen Footprint Tool Network Project Manager Elizabeth Castner, the academic journal features papers on the group’s progress at UVA, the University of New Hampshire, the Marine Biological Laboratory, Dickinson College, Eastern Mennonite University, Colorado State University, Brown University and Colorado College.

The work of UVA’s James Galloway highlighting the impact of reactive nitrogen has spawned a network of colleges interested in reducing their nitrogen outputs. (Photo by Dan Addison, University Communications)

The vast majority of nitrogen exists as a harmless, inert gas. The remainder of reactive nitrogen, however, is found in a variety of forms, including nitrate, ammonia and nitrous oxide.

Energy use and food production are the two main components of the nitrogen footprint model created by Galloway and Leach, who is helping the University of New Hampshire implement the tool as a Ph.D. student there.

As measured by their calculations, an institution’s nitrogen footprint presents a broad picture of campus sustainability related to how reactive nitrogen contributes to both local and global impacts on the ecosystem and human health. Reactive nitrogen is a byproduct of burning fossil fuels, while the production, harvesting and transport of food for campus dining halls also result in the unintentional release of reactive nitrogen to the environment. The remaining institutional sources of nitrogen include transportation, fertilizer use and waste.

Knowing what creates a nitrogen footprint can help reduce it, Castner said. “What makes this tool unique among other campus sustainability assessments is that we are able to account for the environmental impact of food production, which is not explicitly captured in attempts to measure carbon footprints or other tools,” she said. “With the Nitrogen Footprint Tool, we can also make projections and calculate scenarios for how the footprint may change with new buildings on campus or population increases. The tool also has projection and scenario capabilities for sustainability strategies aimed at reducing the footprint.”

The papers published in this special issue of “Sustainability” highlight the strength of the Nitrogen Footprint Tool as an adaptable campus sustainability tool that brings together staff, faculty and students across disciplines to understand how institution and community decisions contribute to nitrogen pollution, Leach said. Because decisions that impact institutional nitrogen footprints occur on multiple levels, from student food choices in the dining halls to electric utility management, Leach said strategies to address nitrogen emissions should address choices made not only at the institutional level, but also at the individual level for students, faculty and administrators.

At UVA, the Nitrogen Footprint Tool Network has worked in collaboration with the University’s Office for Sustainability, as well as working with student groups – all helping to promote awareness of the ongoing efforts and helping to collect environmental and economic data related to UVA’s nitrogen footprint.

Andrea Trimble, director of UVA’s Office for Sustainability, called the work of Galloway, Castner and Leach “a phenomenal example of using Grounds as a living laboratory for sustainability.”

“In addition to the transformative research the team is undertaking, the team has been proactively collaborating across the University to put their research concepts into practice,” Trimble said.

“The impact of the team applying their work on Grounds is demonstrated through the measurable reductions that have already been achieved in UVA’s nitrogen footprint relative to 2010, as well as the increasing awareness within the UVA community about the impacts of nitrogen. In the Office for Sustainability, we often seek to create replicable models to amplify the impact of our initiatives beyond Grounds, and this team’s work initiating and developing the Nitrogen Footprint Network is the perfect example of a replicable model that extends principles and practices to other institutions for the benefit of the global environment.”

One of the Sustainability articles, written by Leach and her colleagues, outlines plans for a new online campus sustainability tool to measure both campus carbon and nitrogen footprints. The Nitrogen Footprint Tool Network is working with the University of New Hampshire Sustainability Institute to build the nitrogen footprint tool into the Campus Carbon Calculator. Scheduled to be launched this fall, this tool will enable institutions to calculate their nitrogen and carbon footprints together.

“We’re really excited about this, because this will bring the nitrogen footprint tool to hundreds if not more universities and campuses across the U.S. and around the world,” Leach said.

To read the papers published in the special Issue on Nitrogen Footprints published by “Sustainability: The Journal of Record,” click here.

To learn more about nitrogen footprint tools for institutions and other entities, and to calculate your personal nitrogen footprint, visit www.n-print.org.