- U.S. Department of Homeland Security/Federal Emergency Management Agency
- Orange County, Florida
- Our Role
- Geographic Information Systems, Hydrology and Hydraulics, Floodplain Mapping, Quality Assurance/Quality Control, Outreach.
- 135 square miles
- In Progress
- Performed a detailed H&H review of an ICPR model for the Lake Apopka Basin
- Performed initial floodplain mapping of ICPR results using LiDAR
- Provided FEMA and community with technical guidance on path forward.
Florida’s third-largest lake, Lake Apopka in Orange County, Florida, was once considered the premier bass fishing location in the world. However, development around the lake has increased the Lake Apopka flood risk. The Federal Emergency Management Agency (FEMA) implemented its Risk Mapping, Assessment, and Planning (Risk MAP) program for the basin to update flood hazards and to develop strategies to help mitigate flooding risks.
Gannett Fleming provided a detailed technical hydrologic and hydraulic (H&H) review of an Interconnected Channel and Pond Routing (ICPR) model covering the Lake Apopka basin within Orange County.
Before FEMA agreed to revise the flood hazards based on this model, Gannett Fleming reviewed the hydrologic and hydraulic model input and simulation results for the ICPR model. Model characteristics were reviewed at both a global and local scale. To support the review, custom Geographic Information Systems (GIS) tools were used to analyze the data. Sub-basins were delineated across the basin, and surrounding lakes, depressions, and riverine reaches were mapped to validate the modeling results. A list of technical comments that resulted from the review were communicated to the community and FEMA. The results from this review determined that the data and modeling are not consistent with FEMA standards and engineering practices, making the model insufficient in updating the FEMA Flood Insurance Rate Maps.
- Quality assurance/quality control
- H&H analysis
- Floodplain mapping
- Community outreach.