New Service Provided by State Agency in Oregon: Base Flood Elevation Determinations Jed Roberts, MS, CFM Flood Mapping Coordinator Oregon Department of Geology and Mineral Industries (DOGAMI)
About DOGAMI We Are Experts in Natural Hazard Mapping Lidar Based Landslide Inventory Map in NW Oregon Landslide
About DOGAMI We Are Experts in Natural Hazard Mapping Volcanic Lahar Deposits in the Sandy River Basin on Mt. Hood s West Flank Volcanic Hazards
About DOGAMI We Are Experts in Natural Hazard Mapping Five Cascadia Tsunami Inundation Scenarios in Seaside, Oregon Tsunami Inundation
About DOGAMI We Are Experts in Natural Hazard Mapping Channel Migration Channel Migration Zone Mapping of the Coquille River in SW Oregon
About DOGAMI We Are Experts in Natural Hazard Mapping Lidar Based Flood Mapping in Coquille, Oregon Coastal and Riverine Flooding
About DOGAMI We Acquire and Store Lidar for Oregon
DOGAMI is a FEMA Region X Cooperating Technical Partner Existing FIRM DOGAMI Revised FIRM We Revise Flood Insurance Rate Maps
Basic Hydraulic Models to Revise Approximate Flood Zones (i.e. Zone A) Produces Water Surface Elevations (aka BFEs!) FEMA Approved Approach! Cross sections Extracted from Lidar Bridge Geometry Inferred ASFPM 14 Seattle, WA June 5, 2014
Basic Hydraulic Models to Revise Approximate Flood Zones (i.e. Zone A) Produces Water Surface Elevations (aka BFEs!) FEMA Approved Approach! Water Surface for 100 year Flood Event Sandy River, NW Oregon
Lidar based hydraulic modeling fixes huge and systematic problems with existing Zone A delineations. Existing Zone A Delineation Modeled Zone A Delineation
DOGAMI has modeled hundreds of miles of Zone A in Oregon, but the new mapping will not be published by FEMA for years. Unpublished Flood Maps Revised by DOGAMI How do we get new mapping to people who need it now? What about areas with no prospects of new FEMA flood maps?
Base Flood Elevation (BFE) Determination Service Where modeling has been completed, DOGAMI will provide an official letter stating the BFE. (For $50 fee to cover our time.) Example BFE determination letter
Base Flood Elevation (BFE) Determination Service Where modeling is needed DOGAMI will produce a published study and official letter. Map Produced with BFE Determination Study ASFPM 14 Seattle, WA June 5, 2014
Base Flood Elevation (BFE) Determination Service Can produce study for land surveyor, professional engineer, or local government/agency. Report Produced with BFE Determination Study
Base Flood Elevation (BFE) Determination Service ADVANTAGES State agencies are recognized by FEMA as authoritative sources of BFE information; no time consuming review by FEMA is required during the Letter of Map Amendment process. Studies are performed according to FEMA flood mapping standards. Fills a void in services not offered by many professional land surveyors or engineers. Affordable, more so when cost is spread across multiple parties. BFE Determination Fact Sheet Study and supporting data is made available for free on the DOGAMI website.
Base Flood Elevation (BFE) Determination Service DISCLAIMERS FEMA may, at any time in the future, revise BFEs for a given area. Basic hydraulic studies do not supersede existing or future detailed hydraulic studies that include field survey data. Some areas have very complex hydrology and/or hydraulics and are not appropriate for basic studies even if they are currently mapped as Zone A. Hydraulic studies do not necessarily identify all areas subject to flooding, particularly from local drainage sources of small size. BFE Determination Fact Sheet
Base Flood Elevation (BFE) Determination Service HOW IS IT GOING? Have not officially publicized the existence of the service planning to launch website and fact sheet with news release next month. Word of mouth has led to one hydraulic study and several BFE determination letters. Have requests for more letters in the queue. Expectation is that interest will grow in the near term due to phasing in of higher flood insurance rates and new penalties for banks. BFE Determination Website Please spread the word!
Jed Roberts Flood Mapping Coordinator Oregon Department of Geology & Mineral Industries (DOGAMI) Portland Office jed.roberts@dogami.state.or.us (971) 673 1546