After graduating from Harvard, she worked alongside Michael Van Valkenburgh in landscape architecture while also teaching at the University of Minnesota. In 1992, Bargmann founded D.I.R.T, a landscape design studio in Charlottesville, Virginia. She turned what was commonly seen as trash into sculptures and art pieces. One of the projects D.I.R.T focused on was reutilizing former landfill sites into public spaces, such as parks and playgrounds. She also collaborated with various artists, historians, hydrologist, and members of the local community to reconstruct Vintondale, Pennsylvania's acid mine drainage into Vintondale Reclamation Park. Bargmann has stated that she likes to incorporate a site's past into its future because "there’s something dishonest and superficial about giving a site’s physical appearance precedence over its function and history." During this time, Bargmann accepted a position University of VirginiaSchool of Architecture while still continuing to work with D.I.R.T. In 1998, she was a contributing editor to the Landscape Journal from the University of Wisconsin Press. In 2000, Bargmann and architect William McDonoug collaborated to repurpose a 1,200-acre Ford Motor Corporation plant in Dearborn, Michigan. As the site was heavily polluted, she received $2 billion to make it ecological friendly. The following year, she received a National Design Awards for her environmental design projects. She later received a fellowship at the Parsons School of Design, School of Constructed Environments. In 2007, she collaborated with Manu Sobti to co-teach at Urban Edge Studio to repurpose Milwaukee’s decaying landscape. As a result of her efforts, she was the recipient of the University of Wisconsin–Milwaukee School of Architecture & Urban Planning "Urban Edge award". A few years later, Bargmann and D.I.R.T were hired to renovate Urban Outfitters headquarters from an abandoned Navy Yard. She constructed the exterior landscaping around the building to include pathways, laws, and dog parks. As part of the land included a working Navy base, she uncovered and designed ship crainways, ecological floating wetlands, and reused debris as pavers to turn the site into an ecological friendly landscape. In 2019, she was named a juror for the DIA Plaza Design Competition hosted by the Detroit Institute of Arts and Midtown Detroit, Inc.
