Mass Freezing as a Large-Scale Archival Rescue Strategy: Lessons from the 2024 Floods in Southern Brazil

The devastating floods that struck Rio Grande do Sul, Brazil, in April 2024 severely damaged over a hundred archival collections, including those of the Federal University of Santa Maria (UFSM), where 12,000 boxes of historical documents (1930–2024) were submerged. In response, UFSM implemented an innovative and largest mass-freezing operation for archival records in Brazil—and probably in the world—, stabilizing 12,000 boxes in four refrigerated containers at -20°C. This emergency strategy was conducted under strict protocols, including vacuum-sealing the documents and using perforated plastic boxes, ensuring uniform cold air circulation and long-term preservation for future recovery. UFSM transformed this crisis into a sustainable preservation initiative by establishing TransDoc, a specialized archival-recovery laboratory and reference center. TransDoc integrates interdisciplinary expertise from Archival Science, Chemistry, Biology, Food Technology, Engineering, and Information Technology to develop innovative methodologies for water-damaged documents. Beyond preserving its institutional memory, TransDoc now supports other affected institutions by sharing innovative methodologies and best practices, assisting eight federal institutions affected by the May 2024 floods. In partnership with the National Archives of Brazil, it is leading the recovery of approximately 30,000 archival boxes. This case study underscores the importance of rapid response, advanced preservation techniques, and interdisciplinary collaboration in mitigating climate-related archival losses, safeguarding historical records during natural disasters. UFSM’s experience serves as a model for institutions worldwide, demonstrating how innovation and large-scale rescue operations can ensure the survival of archives at risk in the face of increasingly frequent climate-related disasters. The 2024 floods, therefore, represented a milestone for documentary preservation in the country, while simultaneously driving the creation of a national reference center, essential for ongoing recovery and long-term preparedness against future disasters.