Flood Insurance Studies
The Oregon Department of Geology and Mineral Industries (DOGAMI) partners with FEMA Region 10 to improve mapping of flood hazards for the National Flood Insurance Program.
Since 2008 DOGAMI has received grant funding through FEMA’s Risk MAP and Cooperating Technical Partners programs to revise flood maps using the latest in lidar technology, hydrologic observation, and hydraulic modeling. In addition to improving the science behind the maps, we have upgraded the presentation by highlighting buildings and showing lidar topography in shaded relief.
Example of (left) old flood map and (right) new flood map produced by DOGAMI.
Precise and accurate topographic information is key to producing credible flood maps – lidar technology provides that information. Through the Oregon Lidar Consortium, we have acquired and leveraged the highest quality lidar in the nation for flood mapping.
This set of images shows the added detail afforded by lidar in flood mapping. A flood map created from decades-old topographic maps is shown on the left. The same area is shown on the right, mapped by lidar, revealing high ground never captured before.
Coastal Flood Mapping
Scientists in our coastal field office are using pioneering techniques in wave modeling and erosion analysis to better understand flood risk along Oregon’s coastline. We have performed field surveys at hundreds of locations to gather information about beach response to winter storms. We have also partnered with scientists at Oregon State University to collect new bathymetry data (the underwater corollary of topographic data) needed to understand how waves will break in large storm events. By 2015 we will have re-mapped the entire Oregon coastline.
DOGAMI Publication: Special Paper 44, Coastal Flood Insurance Study, Coos County, Oregon
DOGAMI’s Jonathan Allan visiting a field survey site.