Widespread flooding throughout the island of Ireland during Winter 2015/2016 demonstrated the substantial financial and social consequences for communities, resulting in the temporary displacement of numerous residents and extended disruption to business trading. Following a flood event, a series of persistent problems often emerge, such as difficulties associated with renewing flood insurance policies. These persevering problems are secondary stressors, which are ongoing implications indirectly linked to a defined prior event, potentially contributing to psychological stress among affected individuals and hindering continuation of normal daily activities. As yet insubstantial quantification of flood-related secondary stressors has been conducted, hence it is challenging to establish where government resources are best employed. Furthermore, despite the existence of various studies examining the psychological health consequences of flooding on residents, limited research has assessed the implications for persons in charge of businesses. This research investigates the secondary stressors experienced by flood-affected residents and businesses within the island of Ireland, appraising the psychological health implications. Evaluation of preparedness and community resilience is undertaken, as well as consideration of the current effectiveness of flood-related social media communication by organisations in Northern Ireland. A mixed-method research design consisting of questionnaire surveys, interviews and social media data extraction was used to collect the empirical data. Qualitative data analysis was conducted using NVivo, whereas quantitative data analysis was undertaken using SPSS. Quantitative data analysis included the conduction of Principal Component Analysis and the calculation of Relative Importance Indices. A number of key findings emerged from the data analysis. Residents and persons in charge of businesses are affected by a wide range of secondary stressors, many of which have the potential to result in the development of Post-Traumatic Stress Disorder (PTSD). Nevertheless, business owners and managers are at a lower risk of developing PTSD in comparison to residents. Significantly, perception of future flood risk is low among residents and businesses and current flood warning mechanisms are insufficient, with the potential to intensify the impact of secondary stressors. Furthermore, the limited uptake of flood resilience and resistance measures and the inadequacy of community flood resilience within flood risk areas increases vulnerability to future flood events. Additionally, analysis concluded that the full potential of social media as a communication tool in relation to flooding is not being met in Northern Ireland. The findings have substantial implications for policy makers; prompting recommendations concerning development of specific flood guidance in Northern Ireland, official records detailing flood-affected businesses and clear guidelines for organisational use of social media in relation to flooding. Furthermore, practical recommendations are outlined including developing community consultation, increasing understanding of flood insurance policies, reviewing current post-flood financial assistance schemes, improving flood risk awareness and enhancing community resilience via social media.