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Chapter 10:Hazard Analysis—Floods <br /> Currently, the areas landward of County's levees are mapped as "X Zones" on FEMA's <br /> Flood Insurance Rate Maps (FIRM). Areas designated as "X Zones" are not considered by <br /> FEMA as being subject to 100-year (1%) flood inundation. Mortgaged structures located <br /> within "X Zones" are not required to have flood insurance under National Flood Insurance <br /> Program (NFTP), or the flood insurance premium is greatly reduced. <br /> If the levees are not certified in accordance with the PAL Agreement and 44 CFR 65.10, the <br /> area landward of the levees will be remapped on the FIRM as "A Zone" Special Flood <br /> Hazard Areas (SFHA). Areas designated as "A Zone" SFHA are considered by FEMA as <br /> being subject to 100-year(1%) flood inundation. Any mortgaged structure located within an <br /> "A Zone" SFHA is required to have NFIP flood insurance. The annual premium for NFIP <br /> flood insurance can be in the thousands of dollars. <br /> If the County's levees are not certified, Table 10-4 presents an estimate of the acres of <br /> inundation (64 aces) and number of parcels (175 parcels) potentially affected (Refer to <br /> Figures 1, 2 and 3 for: the location of the levees; flood sources; estimated 100-year (1%) <br /> flood inundation areas landward of the levees; and,potentially affected parcels). <br /> Table 10-4. Estimated Inundation Area and Number of Parcels Potentially Affected if Levees are not Certified <br /> FEMA Levee Tnundation Area, <br /> Object ID Flood Source acres(i) No.of Parcel'" <br /> 11 Waiakea Stream 12 10 <br /> 12&20 Alenaio Stream 43 133 <br /> --- Paauau Stream 9 32 <br /> Total 64 acres 175 parcels <br /> (1) Based on the inundation areas shown on Figures 1,2 and 3. <br /> The USACE has the expertise to prepare the certification documentation requested by <br /> FEMA. As part of the USACE Interagency and International Support Authority, the County <br /> entered into a Memorandum of Agreement with the USACE, on October 1, 2008. Under the <br /> October 1 MOA, the USACE will assist the County in acquiring, assembling and submitting <br /> the necessary levee certification documentation to FEMA for Alenaio Stream (PAL Levee <br /> Nos. 12 & 20), Waiakea Stream (PAL Levee No. 11) and Paauau Stream (no PAL no. <br /> assigned). See Table 10-5. <br /> Table 10-5. USACE October 1 MOA Com ensation Allocation <br /> FEMA Levee Flood Source HUD Funds County Funds Total Funds <br /> Object ID (10%) (90%) <br /> 11 Waiakea Stream $ 27,500 $ 247,500 $ 275,000 <br /> 12&20 Alenaio Stream 14,500 130,500 $ 145,000 <br /> --- Paauau Stream 14,500 130,500 $ 145,000 <br /> Total $ 56,500 $ 508,500 $ 565,000 <br /> 10.4.1.2 Accuracy and Completeness ofFlood Zone Mapping <br /> Many known flood-prone areas have minimal FIRM coverage (e.g., upper Puna). Some <br /> FIRM maps do not completely include all flood areas, as evidenced by the November 2000 <br /> flooding (e.g., FIRM maps for Hilo). FEMA and the County are working to digitize the <br /> FTRMs, which should be completed by late 2010 or early 2011. Figure 10-9 shows those <br /> 10-30 Hawaii County Multi-Hazard Mitigation Plan <br />