From a desert to an oasis: Penn engages in ambitious greening effort in the Sahel
Students from the Weitzman School of Design journeyed to Senegal to help with an ambitious ecological and infrastructural greening effort as part of their coursework. The Dakar Greenbelt aims to combat desertification and promote sustainable urban growth.
In Senegal, the ambitious Dakar Greenbelt project seeks to create an extensive network of ecological infrastructure in and around the city to sustainably address environmental concerns and enhance urban life. With support from David Gouverneur and Ellen Neises, Ph.D. candidate Rob Levinthal in the Weitzman School of Design led two courses that included a field trip to Dakar, that culminated in students presenting their visions for parts of the Greenbelt.
(Image: Courtesy of Chaowu Li)
From leadership strife and regional conflicts to the sweeping waves of global economic transformation, the Sahel region—the southern edge of the Sahara Desert—has endured a century of dramatic change that has profoundly shaped life for its growing population, says Rob Levinthal, a Ph.D. candidate in City and Regional Planning at the Weitzman School of Design. Urbanization, industrialization, and modernization have drifted across the African continent, but in the fragile ecosystems of the Sahel, he notes that these trends have exacerbated the region’s challenges and have intensified desertification and rendered the land increasingly inhospitable.
The Sahara Desert threatens to steadily disrupt the Sahel, driven by deforestation and unplanned urban growth, further threatening the livelihoods of millions, says Levinthal, who, prior to joining Penn, spent 27 months serving in the Peace Corps in Senegal. “The effects of deforestation, land degradation, and a changing climate have made the ecological conditions pretty dire in some places,” he says. “My job there was planting trees as a part of an agroforestry effort and we were struggling to do even that, as we had a limited number of collaborators in these different villages that I was living in.”
During this time, Levinthal caught wind of a “huge, ambitious project that was planting a line of trees across the continent.” The Great Green Wall Initiative (GGWI) is a multinational effort to combat deforestation and desertification that seeks to create a living wall of vegetation spanning the width of Africa.
Intrigued with the project, Levinthal began to ask, “How is this happening? What were the skills needed join? Who was in charge of making these large-scale projects?”
Lac Mbeubeuss, Dakar’s sprawling landfill, sits at the intersection of urban expansion and environmental degradation, where waste pollution threatens surrounding wetlands.
(Image: Courtesy of Chaowu Li)
Advocating for broader involvement in the Dakar Greenbelt project at Penn, Levinthal engaged faculty members Ellen Neises, David Gouverneur, Eugénie Birch, and others. That team then helped secure funding for the project from Penn Global and PennPraxis to support two parallel courses offered this fall: a design/build studio tailored to landscape architecture students and one for a city and regional planning students, both focused on designing and planning the Greenbelt. At the start of the semester, students in these courses traveled to Senegal, immersing themselves in the local environment and collaborating with community members and project partners. Informed by their experiences in Dakar, students developed comprehensive plans for the Greenbelt, which they presented as their final projects shortly before the December break.
“It’s been truly wonderful to be part of a project this profound and far-reaching,” says Neises, pointing to the opportunity for students and faculty to meet with environmental activists and national leaders in Senegal and to contribute to the local community there working on the Greenbelt project.
Origins of the Wall and the emergence of the Belt
Levinthal notes that the original idea to “plant a line of trees across the continent” dates back to the 1970s, during a period of severe drought, when forester Richard St. Barbe Baker traveled from Senegal to Kenya and was shocked by the levels of deforestation and envisioned a “green front.”
While Baker’s vision for a physical barrier of trees to halt the expansion of the Sahara Desert did not come to fruition at the time, the African Union revived the concept in 2007, resulting in the GGWI. The project has since grown to include human communities, sustainable farming, livestock cultivation, and efforts to improve food security.
“The goal for GGWI is to create a roughly 15-kilometer-wide green belt across the continent, covering about 8,000 kilometers in total, but it’s so much more than trees,” says Neises. “Picture a mosaic of different projects, each tailored to local conditions and needs. In some areas, this means planting drought-resistant trees and creating social spaces, whereas in others, it involves restoring grasslands or introducing sustainable farming practices and other forms of green economic development.”
Framing the studios
Speaking to the importance of local participation, Levinthal notes that “conservation and restoration plans can’t work unless the community buys into it.” Thus, both studios engaged with local communities and leaders before and after their trip to Senegal.
Penn students and Senegalese partners examine a local aquaculture system, exploring sustainable water management techniques.
(Image: Courtesy of Chaowu Li)
The partners in Senegal identified five sites in and around the Dakar metropolitan region for the students to research and structure their preliminary proposals. The two classes were then assigned shared activities, like regional analysis of the natural, urban, and social systems.
Once they completed preliminary research and workshops held with local authorities and communities, the students traveled to Dakar, where they met and toured with the Senegalese partners. There, the group visited locations including Toubab Dialao, Lac Mbeubeuss, Lac Rose, Technopole, the Dakar Plateau, the Almadies, Thies, and informal settlements on the outskirts of the city.
The site visits “allowed us to develop more focused and context-specific proposals, which we believe can serve as a helpful basis for future plans for the city and region,” says Sylvanus Duamor, a master’s student in city planning.
Penn students, Senegalese officials, and community leaders gather on-site to discuss urban greening strategies and sustainable development in Dakar. Among them, Ellen Neises and David Gouverneur (right) engage in conversation with local experts, exploring how nature-based solutions can address environmental challenges in rapidly growing cities.
(Image: Courtesy of Chaowu Li)
As an international student from Ghana, Duamor says that the work he and his classmates were a part of felt very close to home. “Ghana and Senegal are a lot alike,” he says, “both bear rich cultural heritages, vibrant music scenes, and delicious cuisines, and similarly, they also face similar urban planning challenges.”
“What was particularly inspiring from a city planning perspective,” says Duamor, “was the spatial pattern of the sprawling areas and the efforts to protect resource lands such as natural areas, wetlands, forests, streams, arable lands, and wildlife habitats.”
Workshops and community meetings became a cornerstone of the trip. Students collaborated with activists, government officials, and residents to identify pressing concerns, such as waste management and aquifer pollution.
Briana Parsons of the School of Veterinary Medicine presents on the intersections of agriculture, social services, and environmental sustainability.
(Image: Courtesy of Chaowu Li)
The fieldwork was a remarkable experience and involved long hot days and working through language differences, notes Neises. “One of the students said that eating and traveling with 20 Senegalese experts—seeing the culture and landscape through their eyes and interactions—was one of the most amazing experiences of her life and one she’ll never forget. I think we all felt that way.”
Levinthal says one of the most rewarding parts of the trip was seeing the students engage with the Senegalese partners and watching friendships and genuine connections begin to form.
“I was struck by the energy and enthusiasm of the students, both from the American and Senegalese teams,” says Karim Kebe, a physical scientist at the Cheikh Anta Diop University of Dakar. “Their ability to ask relevant questions, their intellectual curiosity, and their active engagement in research and workshop activities enriched the discussions and fostered meaningful exchanges. This inter-university collaboration highlighted the importance of openness and knowledge sharing when tackling complex urban planning challenges.”
Bringing it back to Penn
Upon returning to Penn, the studios addressed the Greenbelt project through complementary approaches, blending urban and site-specific strategies across both disciplines. City Planning and Landscape Architecture students collaborated and explored environmental, urban, and social challenges at different scales, with planners contributing designs and architects addressing broader frameworks alongside their detailed interventions.
Both groups worked on macro-level strategies, including network improvements for transportation, energy, and waste systems to support the Greenbelt’s long-term sustainability. The students developed a regulatory framework, stakeholder maps, and policy briefs while proposing site-specific solutions for wetlands restoration, flood management, and green infrastructure. Collaborations with firms Biohabitats, Inc. and MASS Design Group and experts like Brianna Parson from the School of Veterinary Medicine at Penn and her partner Sulay Camara from FAIR Farms Gambia enriched the projects with innovative insights into low-carbon and biogenic materials for ecological restoration.
“These designs are ambitious yet actionable,” says Levinthal. “The students took everything they learned from the field—both the data and the stories—and transformed it into alternatives that directly address the challenges they witnessed.”
“I chose to develop a proposal for an area of Dakar that floods frequently,” says Maria Fairchild, a master’s student in the landscape architecture program. “The community had expressed very specific desires about the kinds of green space and flood mitigation strategies they wanted to see in these areas, so I tried to capture their ideas as much as possible while we were there. Instead of foregrounding my own design ideas, I tried to just translate what they had said in community workshops into the visuals I was creating.”
At the final review in December, students presented their work to faculty, peers, and external stakeholders. Highlights included strategies for rehabilitating critical wetlands, mitigating flooding, and establishing a circular waste economy to turn pollutants into resources.
(Top) Ellen Neises (right) and students present a large-scale ecological and urban planning proposal for the Dakar Greenbelt. The presentation, held in collaboration with local partners, outlined strategies for sustainable land management, flood resilience, and green infrastructure integration. (Bottom left) Briana Belo (right), a Master of City Planning student, presents her team’s proposal for the Dakar Greenbelt. (Bottom right) Students finalize their presentation boards, showcasing design proposals for Zone 02 near Mbow University in Dakar. Their work focuses on wetland restoration, flood management, and sustainable urban development as part of the Greenbelt.
(Top image: Courtesy of Chaowu Li; bottom images: Eric Sucar)
“What they achieved is a model for combining academic research with real-world application,” Gouverneur says.
With pilot projects scheduled to begin in 2025, the collaboration between Penn and Senegal is poised to become a model for integrating education, ecological restoration, and urban planning. The project’s dual focus on addressing environmental crises and empowering local communities underscores its significance as a global initiative.
Reflecting on the partnership with Penn, Kebe says he has enjoyed continuing to exchange ideas with some Penn faculty and students and notes that these discussions, primarily focused on ongoing research projects, have fueled much of his thinking and deepened his knowledge in urban planning, spatial analysis, and geomatics.
“This experience has been incredibly enriching on multiple levels,” Kebe says. “It has strengthened my commitment to promoting innovative and sustainable solutions to address urbanization challenges in Senegal. I firmly believe that this type of international collaboration is essential for developing tools and approaches that are well-suited to our local realities while incorporating best practices from around the world.”
Duamor notes that the experience underscored the importance of developing solutions tailored to the specific context of the area. “Generic solutions may not address the unique challenges of a region, so it’s, really important to consider local conditions and cultural nuances,” he says. “I intend to carry these lessons with me as valuable resources throughout my career in urban and regional planning, making me a more effective and empathetic professional.”
“It’s been an incredible honor to see this work evolve,” Neises says. “This project is not only a testament to Penn’s commitment to sustainability but also a reminder of the power of partnerships to drive transformative change. We’re excited to see these ideas come to life over the next few years.”
Building on the proposal she developed in the course, Fairchild is undertaking an independent study this spring. “I plan to focus on developing detailed design drawings for one of these pilot sites, likely in a commune called Keur Massar,” she says.
Levinthal hopes to see the GGWI thrive as he continues his own work on the Greenbelt. He hopes it will create numerous green jobs for those that want them, restore degraded ecosystems for biodiversity, and improve human well-being.
“As the GGWI evolves to a wider, more all-encompassing mission, I think that greenbelts in rapidly expanding cities are a way to build resilience and sustainability in arid and semi-arid environments with limited natural resources,” he says.
Students from the Weitzman School of Design present their final proposals for the Dakar Greenbelt project, showcasing site-specific strategies for ecological restoration and urban resilience. Faculty and peers provide feedback, reflecting on the project’s potential impact.
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