Trust and the communication of flood risks: comparing the roles of local governments, volunteers in emergency services, and neighbours.

Risk information need to be communicated by trusted groups, in order to promote attitude and behaviour change. We compare different levels of trust in local governments, volunteers in emergency and relief services, and neighbours, and how trust in these groups shapes citizens' perceptions and actions relating to flood risks. Structural equation modelling is applied to a sample of 2007 flood-prone households in Austria. A series of cognitive and behavioural responses to flood risks is regressed on trust shown to the three groups. Our findings show that citizens show great trust and attribute high competence to volunteers, which increases risk perception and reduces denial and wishful thinking. Trust in local government downplays risks, makes citizens rely on external help, and promotes fatalism and wishful thinking. Trust in neighbours increases reliance on social support and reinforces wishful thinking. These trust effects reflect the roles and risk narratives of the respective groups. To stimulate specific actions of citizens in flood risk management, the group which addresses the desired actions within its narrative should act as risk communicator. Risk communication could be introduced as a complementary activity in voluntary emergency and relief services, wherein older, retired volunteers seem particularly qualified as risk communicators.