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<br />NFIP map products have evolved Aver the years, but their pt)Xluction has always taken ,/
<br />place within real-world fiscal constraj.~s(The focus ofFIRMA1(eParation has been and //;'/
<br />continues to ,be the hydrologic ang.}{ydraulic analyses. The{Wl:P is neither intended nor :fu1lded
<br />to produce b~se maps. Ratheryn.iV~li:;"have been c~trated on developing acc"f<tiood-
<br />hazard d~~d using, wh~~ver possibte;'~~e ~...aVailable fro~ another sour~y8lich'a;~~e
<br />commumt1i state, or otheykderal agency [SuCbJis1he U.S. GeologICal Survey,{VSGS)]. '\,'\\ '
<br />Initially, the NFIP ~d flood-hazard data from various sources, such as)f..86s flood-prone'\',. /~>
<br />quadran~e m~~~;9~t1oodpla!n information re?orts produ~ed and ~ubli~ed'bY agencies such as '~:v;i;>/
<br />the U.&;~)2orps ofEngmeers or U.S. SOli ConservatIOn ServI9.e/From the late 1960s to the//
<br />LIMIT omid-1970j;:FHBMs were used for a community's initial particip~)ffil in the NFIP (Emergency,<,/
<br />DETAILED spfpY ';rhe NFIP was building from ground zero and neede.d',Wproduce many maps as ql1i'CkrY
<br />a~il ' flle. The maps were crude and approximate, but pojird be refined as communi~M'Oined
<br />gular Program of the NFIP. The maps, most in J)}v/x 17" format, were prodqC~using
<br />\I!i~~anual cartographic techniques, w~4~ade them difficult to revWPrior to
<br />',~~@@d!l1"ie~ were. ~ectilinear, n~rmallyfPtlowing some ~hysical fe~tu~~uch as a road;
<br />~~3-~t~werecurvil!near, followmg}ge'actual topographIc contoyr:/ /
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<br />'92 In the mid-1970s, once mo~ti;om6,t~ities had joined the ~through the Emergency // (
<br />'WbIlfa'M; the NFIP began a concentrate~ ~Jfort to produce more-;detailed FIRMs, which are used /;i/ '\"
<br />for communities' conversion to the Rei~~. FI~tYpically incorporate detailed /// \"
<br />-90 flood-hazard data derived from survey'rand hydrotOgt1}~dihydraulic analyses with approf'i.lDaie '
<br />ZONE Jfiood-hazard analyses already identi~~d that estimate ~agnitude of the one-perce9t'~ual
<br />chance flood. Specifically, these analyses determine the fl'bN height or Base (on;~ertent
<br />annual chance) Flood Elevation (~) and areas of the floo~~in where deve]5>Fnient can occur
<br />as well as areas (floodways) that iliould remain free from obstrtJ.~on to av)li'il~xacerbating the
<br />flood ~,zard. When FIRMs were\f!{st prepared, manual cartograNri.c te~ques involving
<br />scribipt different themes (roads, la~1&, floodplain boundarie~, etc} ~6/different layers were
<br />used/ /rhe layers. wl'l€ ~verlaid to cr6lte';a..negative from which ~aps were printed.
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<br />III From the mid..J970s to the mid-1980~'Flood Bo~ and Floodway Maps (FBFMs)
<br />Mere published a~~-- '" . ns to the FIRMs. U.\;'d I?ri~ily -for floodplain management, they
<br />/~/depict floo?wa~~ut not B r flood risk zo~~)/fiey were typically prepared using the same I
<br />----- ~- ~ / cartographIc ti~.hnlques as FIRM<:. ~ / /
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<br />Publt~d in conjunction with !-~::F(RM and FBFM is the community's Flood Insuranl:~__----;:--==-:-
<br />Study (FIS). lt~~es t.echnical Y~mentation of the detailed flood hazard.:!\I.dy:-~~1l@l~:::::::::=:
<br />summary of the hydi"~~ and ~.dfauhc analyses, the flood profiles, 9900}YJIY-:dafit\libIes;-a
<br />summary of peak dischar~'s,~a transect data tables and still~~!.jJl~:'crest'erevation tables
<br />i i (for coastal studies). Th~~ata are taken directly fro~~~6fogrc and hydraulic analyses
<br />i: used to prepare the stqdy~d, therefore, take pr~gl}Clftwliei determining the BFE) over the
<br />:: FIRM, which is prep'!'f,ed, in turn, based O!l..th~a:mthe FIS report.
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<br />: I Under the 19~Guidql~:r5r~duction was decentralized and moved to study
<br />:--~--=-'':'::'':-~=-W!!!;@eter 10('~tioIiU~~~-wefe responsible for technical and consistency reviews only.
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<br />fvolution of Maps
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