Structure-Specific Flood Risk Assessment Studies

Flooding is a major threat to people, property, and infrastructure in Illinois. To better prepare for flooding disasters and prevent losses, high-quality flood loss information on a structure-by-structure basis is a valuable tool. A structure-by-structure risk assessment provides information that identifies which structures may flood, which frequency of flood impacts structures, the depth of flooding likely for each structure, and the expected losses. One component of this investigation is the field survey data that were collected for individual structures in the City of Ottawa, Peoria County, and parts of Rock Island County, Illinois. Structure-specific risk assessments were performed using this survey data for the City of Ottawa and Peoria County. The steps taken to compile these data and the information necessary to perform the risk assessments are explained. An evaluation of alternative methods to estimate elevations from LiDAR for the project areas is included in this report. A discussion of automated methods to generate building footprint data layers is provided as an appendix