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In shl"t't flow' al'<'a5, velocities would rang~ from 1.3 feet p.:rseeond.ln some localized stream reaches, for example on the inside of bends or downstream from natural or manmade obstructions, velocities of flow could significantly exceed those shown in Table fl, Velocity of flow during n wo.Year flood "vuld besJighUy higher than durin,ll' a lOO.Yl."ar flood. Walerflowingatarateof7feetpersewndor greater will cause :;e'.ere erosion ofst""am_ banks and is capable of lransP<lrtinglar,l!'e rocks. Streambanhand the fill around bridge abutments may be eroded. and large amounts ofgravel.sand,andsiltmaybetranSP<lrledb" water f10wingata rate of 5.7 feet per second. Waterflowingatabout2feetperseeondorless wHl depooitsand,sill. and olher debris. FLOODED AREAS The areas that would be inundated bYlhe lOll-and 500.year floods areshovm on Plates 2~27.As may be seen from Ihaseplates,the area jnundated by the IOO-}.earflocxl along the Yampa River would closely parallel the channel in StellmhoatSprings. Widcr areas would be flooded upstream and downstream from the city. One-hundrcl Ye:lr flooding along the tributary cre<lks would alSOeloscly parallellhe slreamways ex<X'pt where sheet flow and w;der ponding areas would oeeurln lhelowerre~hes'.lntotal.thel0ll_yearfloorl wlluld inundat~ about 670aeres. of which If>Q acr(>S are developed to residential, cammer_ eial,orcivicuses; 190 acres are devoted to agriculture: 2W acres are undevcloped: and 120 aeres are strearnway. F'looding during a liOO.J'ear flOOd Would generally cxtend acrOl:lS the valley floor in complex patterns influenced by manmade structures, Widt" pondinJ< areas and sheet flow areM would occur at variO\ls loeations, and at about the east corporate limit, floodwater from Buteherknife Creek would break OUI IOlhe west and flo"'lhrougbalow nres to comingle with SodaCrcek floodwater northerly of Pine Street. FLOOD DAMAGES Substantial damage would result from a WO--or 5OO-~ar flood. The principal flood losses would comprise residential and com- mercial damage in Steamboat Springs,and dsmsg-o to roads, streets, bridges, culverls. and railrondemb:r.nJcment. Rcsidentinllosses Would include damage to foundations and lower floors, walls, fUrnishinll"s and equip. ment (especially appJianc(>S in basement.s), I_.ns and gard~ns, and private acce~, bridges. Commercia! losses would include .'truetural and equipmelll damage, tern. porary loss of business. and lossotinventory stored On lower floors and in ba.'<Cments. L<.>w. Iyjngstreets.thehighwa,;..andotherroadsin llnd around SteamblmtSprin!o:" would be sub. jeettoinundation:lIlddam~c,andbridgcs and euiv<'rts might be damSJ<ed or destroyed by high velocity flow and flood.bornedebris. Agricultural damage Would principally com. prise the c~ts or """toringsilt and rubble covered fields. Aeeess to various areM could '[1'OOd..<h.IIDwm""I'"dnOwlj"enO,aIlYloM'hontr""'d""p 'h'ho"ldbonOI<<l'h""II.r'~onoododa"''''hownonl'I~IO,2.:;.21m..,..nolbo;n"""."'I."IIo......e';m.ll<<au.... noocl;prod"<ink.IOr""""..r"'.....T;....d"';n.""ba,;"""....ld"<>ln~rilY"'."...,"'"rT.n'IY,AI>b,'h.Tlo", nood'''ll"m"no''IIYI''''h''''llln<h'''lecPlm'J"<J<ourb<YOndtknuoJ''''.reu'''''''.n. " I I I I I I I I I I I I I I I I I I I I I I I I II I I I I I I I I I I I l>e cut off for pcriods ran\:ing from a few hours to a few dll}'S due 10 high water. Strt>ambanks Would be subjeet 10 erosion In various locations due to high velocity flows, The costs of flood fighting and post flood deanup and restorationwouldbesignificanl. Due to the wider flood plain....reaterdepth / ~ l3 of flooding. and highervcloeity of flow duro ing a 500.year flood. damage would be greater than during a 10000year flood. Plates 2.24 ~h"w water surface profiles from which thedeplh or flow in theslream channels and adjacent flooded areas can be determined.