A presentation after 20 days of workshops

Les Ateliers de Cergy organized, as they have every year for over 40 years, an urban and territorial creativity workshop in Île-de-France, bringing together students and young professionals from various nationalities and disciplines (urban planning, art, landscape, engineering, economics, sociology...). 15 young participants from India, Brazil, China, South Africa, Japan, Georgia, Argentina, Greece, and France took part in the collective workshop from September 9 to 25, 2025, proposing representations and actions for the territories of the Upper Seine-Amont Valley, focusing both on the broader basin and on more localized territorial areas.

At the end of the three weeks of work, the three participant teams presented their final proposals before the jury, marking the high point of the workshop. The jury of this 43rd edition, composed of elected officials, local representatives, French and international experts, and partners of the association, gathered on Thursday, September 25, 2025, at the Fabrique de la Cité in Paris, officially closing the workshop. After the presentations, discussions and debates were held to identify ideas that stood out for their creativity, innovation, and relevance, and that could serve as pathways for the future of the Seine basin and its tributaries.

The day began with opening remarks from Brice Gruet, deputy councillor for heritage and tourism development at the Moret-Loing-et-Orvanne town hall, and Laurent Boullanger, director of territorial planning and biodiversity at SDDEA. The workshop coordinators, Armelle Varcin and Cesar Silva Urdaneta, introduced the workshop theme and reiterated its key challenges. Throughout the morning, each of the three teams had 25 minutes to present the essence of their work and the proposals they developed. Each presentation was followed by 30 minutes of exchange with the jury to deepen the discussion.

After the teams’ presentations, the jury—chaired by Pierre-André Périssol, president of Les Ateliers—met in closed session in the early afternoon to deliberate on the proposals. At the end of this session, the workshop coordinators shared a synthesis of the jury’s deliberations. The jury praised the effectiveness of Les Ateliers’ methodology, which enabled the production of rich, multicultural, and multidisciplinary proposals within a limited timeframe.

Three proposals for the Seine-Amont

This 43rd edition yielded three very different yet complementary proposals, each offering original and innovative approaches. The participants strove to adopt an optimistic vision, one that shifts perspective by transcending political, temporal, and often spatial codifications. The teams’ creativity—especially through the use of drawing as a working tool—resonated emotionally and helped awaken a collective awareness of future challenges, emphasizing the importance of involving local populations in projects that affect them. The teams proposed a narrative approach to territorial identity that each basin could adopt to shape its own story.

During the final presentation, the jury continued the dialogue with participants, exploring the issues raised and considering next steps to transform these ideas into concrete actions. This event offered local stakeholders a fresh perspective on how territories can be animated and engaged.

The day concluded with the traditional diploma ceremony for the participants and the coordination team, celebrating their involvement in the workshop.

In 2026, the Île-de-France workshop will continue these reflections on the Grand Jardin Séquanien, turning its attention to the metropolitan Seine.

You can find the list of jury members and the final proposals in the session booklet, available on the dedicated workshop page.

Feel free to write to seine@ateliers.org for further information.

Les Ateliers warmly thank the Fabrique de la Cité for their generous hospitality.