The issue of overload: A mixed methods analysis of activity-related stress and the use of mental health and psychosocial support by spontaneous volunteers during the 2021 flood in Germany

During the 2021 flood in Germany, approximately 100,000 spontaneous volunteers (SVs) participated in response and recovery efforts. Due to the disaster's magnitude, these volunteers faced various stressors. This study examines the psychosocial stress factors and resources of SVs, as well as their utilization of mental health and psychosocial support services (MHPSS), through qualitative interviews with SV coordinators (N = 18, 38.9 % female) and a quantitative web survey of SVs (N = 712, 61.7 % female; 45.9 years). SVs' stress was primarily linked to working conditions (e.g., long hours, task overload) and organizational aspects (e.g., unclear responsibilities, communication), alongside task-specific exposure such as encounters with severely injured individuals. These challenges were particularly pronounced among SVs without institutional affiliation (e.g., Red Cross). Only a minority actively sought external help (MHPSS), while most relied on social support, discussions with fellow SVs, and the meaningfulness of their work for coping. On an organizational level, MHPSS availability and working conditions varied widely, as they largely developed independently of authorities and emergency personnel (AEP). Altruistic motivation, well-planned coordination, and individuals with relevant knowledge, particularly regarding AEP, were identified as crucial resources for managing stress and mitigating risk factors. Findings suggest that SVs require better preparation and support for psychosocial stress management, with SV coordinators playing a key role in implementing qualified MHPSS during and after disasters. To effectively address SVs' needs, a transformation in the design and delivery of MHPSS may be necessary.