Post on 06-Feb-2016
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Preliminary Flood Insurance Rate Maps
Preliminary Flood Insurance Rate Maps
What is a Flood Insurance Rate Map (FIRM) and how do I use it?*• A FIRM is a map created by the NFIP for floodplain management
and insurance purposes. Digital versions of these maps are called DFIRMs.
• A FIRM will generally show a community's base flood elevations, flood zones, and floodplain boundaries. As a property owner/renter, this map is used to get a reliable indication of what flood zone they are in. However, maps are constantly being updated due to changes in geography, construction and mitigation activities, and meteorological events. Therefore, for a truly accurate determination, contact an insurance agent or your community floodplain manager.
*Source: Floodsmart.gov
Preliminary Flood Insurance Rate Maps
• FEMA updates community FIRMs ~ 10 years• Contracts with a private sector engineering
company to conduct hydraulic/hydrologic modeling (in our case Taylor Engineering)
• Contractor works with local communities to collect historic flood information/high water marks
• Current FIRMs dated 2002/2003• Based on USGS 5 foot contour maps• Old data (circa 1980’s)
Preliminary Flood Insurance Rate Maps
• New FIRMs based on county LiDAR data (Light Detection And Ranging)
• LiDAR is a remote sensing method that uses light in the form of a pulsed laser to measure ranges (variable distances) to the Earth. These light pulses—combined with other data recorded by the airborne system— generate precise, three-dimensional information about the shape of the Earth and its surface characteristics.
Preliminary Flood Insurance Rate Maps
Preliminary Flood Insurance Rate Maps
Preliminary Flood Insurance Rate Maps
• Result is extremely accurate topographic data (LiDAR scanners can generally scan with an accuracy of about 2 centimeters (0.79 inches) at an elevation of 4,000 feet)
• Reduces mapping effort and increases efficiency and accuracy
• State-of-the-art science• Particularly important because of Biggert-Waters NFIP
Reform Act of 2012• Preliminary maps become effective February 19, 2014
New Flood Insurance Rate Maps