Flood risk perception near intermediate-sized Kansas dams

Abstract

Kansas ranks second in the largest number of dams in the United States, behind Texas (FEMA 2015). In 2020, Kansas dams reached an average age of 52 years, with many exceeding their designed life expectancy or in need of rehabilitation. Climate change and increased urbanization projections suggest more frequent and extreme flooding in the future, requiring greater demands on current infrastructure (O’Neill et al., 2016). Researchers have explored the physical side of flood risk management to a considerable extent. Still, relatively little is known about how flood risk perception varies in areas associated with at-risk dams. Local populations near intermediate-sized dams are less likely to receive attention due to their size and remoteness but are often more susceptible to failures because of dam construction type and design, lack of knowledge or awareness of dam and reservoir conditions, and irregular maintenance. Dam selection was based on the size and age of the structure, primary purpose, and location. Specifically, dams had to be at least 50 years in age, intended mainly for flood control, and likely to experience increased frequency and more intense 24-hour rainfall totals in the future. Understanding risk perceptions now will help prepare decision-makers for communicating with residents and dealing with disaster situations in the near future. A sequential mixed methods design was applied, whereby quantitative and qualitative approaches were used successively to gain in-depth individual perspectives from selected residents and insights from water resource experts on flood risk perception near at-risk dams. The combination of individual risk evaluations and in-depth personal insights provided by this mixed methodology not only provides basic information about the status of thinking about potential dam hazards, but also may be useful for developing strategies that address risk for people living near intermediate-sized dams. Questionnaires were mailed to 1,100 randomly sampled households near ten selected dam sites in eastern Kansas Purposefully selected interviews were conducted with dam safety and water resource experts associated with the selected dams. Closed-ended data provided through questionnaire responses were analyzed through correlation and contingency analyses to explore statistical significance. Qualitative thematic analysis of interviews and open-ended responses provided depth to the close-ended material, in addition to providing another perspective of flood risk perception near aging dams from dam safety and water resource experts. The quantitative results suggested that flood risk perception was higher among residents located within flood zones, but respondents generally were not concerned with the efficacy of aging dams in their locales. The qualitative results identified and explained variations in outcomes for flood experiences, expectations of the dam in its current state and in the event of a dam failure, flood vulnerability, and risk communication. They provide insight on concerns related to dam management, recent flood events, and of how perception relates to physical risk based on location. A significant concern was the lack of accessible and accurate data for intermediate-sized dams that would contribute to local knowledge on flood risk and improved emergency preparedness for high-risk dams. Intensification of education about dams and flood risk awareness near intermediate-sized dams in Kansas appears to be needed, based on this research. It is likely that such needs also are present in other states. Follow-up research should be conducted to determine the statewide perception of aging dams and their potential to exacerbate flood risks in additional areas. Similar studies should be pursued elsewhere.