Knowing where flooding is likely to occur is key for preparedness, but who knows best about the location of floodwaters? New research from the Social Ecology Team explores this question using public participation GIS data collected in a 2014 door-to-door survey of Newport Beach residents. As part of this survey, residents were asked to draw on a digital map the areas where they had previously seen flooding and areas they thought were at risk of flooding. Social Ecology Team graduate student researcher Wing Cheung and Co-PI Doug Houston compared these resident “sketch maps” of local flood risk against flood risk maps produced by the Federal Emergency Management Agency (FEMA) and the FloodRISE Modeling Team.

Drawing upon this data from 166 survey participants, they observe that residents in some neighborhoods demonstrate greater consensus about the spatial dimensions of flooding than others. They also note neighborhood variations in degree of alignment with FEMA and FloodRISE Modeling Team predictions of where flooding is likely to occur, suggesting that local knowledge can be a vital tool for improving the accuracy and nuance of flood models. Their work also suggests that risk communication strategies could boost preparedness by tailoring messages to neighborhoods with different levels of consensus about the likely location of floodwaters. For example, limited risk communication resources might best be targeted toward neighborhoods with a wide variation of perspectives about where flooding is likely to occur, or toward neighborhoods with a consensus about flood locations that differ significantly from so-called expert predictions. Acknowledging and affirming differently-situated forms of knowledge is critical in building flood resilience, and represents an important step toward increasing local preparedness.

Visit Science Direct for the full article.