1
ANCIENT, HISTORICAL AND POTENTIAL FLOODS Introduction Arbeles In ne Nsoapers and Journa ls have reported several !lreat floods along Th e 5011 RI'Itlr within thll Ternve Quadrangle dur ng the last 100 yeats Indications of anCient floorllng dUring thn 19"T 1500 yearn or more h1:lve found <110119 II \:I SCllt Rrvl::H (II study sites of the pre histone Hohokarn Indian clvlllzat on Tile mhnh Ih ;'I rr.o 110m at least l!.iOO to GOO years ago (Masse 1976) GeologiC eVidence noted n the Tempe OUflrlmnglc nnd nc,Huy ilrt);;" If HJI(;(l\t: yrwt lIoods hal/e occurred hera countless ti mes for at least two m lion )oMtS OIH 1\ me rece llt floods tile ones Within the las t 100 years seem more spectacu lar because VIVid WI uen accounts are al/mlnhle For {)xClmplc thr. dp.pth of ""Htl r dunng February 1891 flooc was reported to be belly h gh on a pony near t he vllla!]e of l eh! east of TerTlllelPewe 1978) In November 19O!.i all three railroad bridges across the Salt River at Tempe were dnm[l!]cn t he olner M mr:lpi and Piluellill R<Jlliuat.ilmt.il:l€ t.iililliltjetl so badly that It was aMndoned The north approaches of · he new steel Maricopa and PIiO!:lfllll lmtlye alltl Ihe PhoenlJ( and Eas tern Railroad bridge we re both washed In Fohmar,192(l thc south abutments fot both tht:; C!:Intnti AV\:HIU!:l lJrn j ytl <JlIlj thtl illyl ""ay bridge at Tempe \0\ ere damaged (Corps of En!] lneers 1957) The greatest flood of h stor cill rccord Irl 1891 <llld II hatl a ,: It;Iak 1I0w o f about 260 000 cub iC feet per second (cb) (7363 cub c per seeonc1 ems) thrOllgh th r. Telllpe Uuadrangfe me[lsured at Granite Reef Dam, that fl oodflow was 300 000 cis (8495 ems) The lB!)1 flood dJrnnOed III thr r IIlrlJarl br If l II e Valley am] c ut tel€\jraph con nectlo ns wrth the West for nine days More than 100 famili es lost their homes anc1 f \ e lives ",ele lost An outline ot the approximate area thought to ha\e been flooded IS indicated on the map (U S 19691 Tile flood uounuaJles were estmlated flom newspaper accounts and infOrmation In files 6t t he Mar cope Fl ood Control District A minor ehlmgc III til outline IS Ildlcated to r downto\o\n Tempe by our study A statistical f lood frequency wble hns hr.r.n compiled by the Corps of Engineers ut Ilzlng Sa lt Rlvt:;r f loodflow data s nce 1891 (see Table 2 on reverse Side of thiS sheet) The geolonlc floodpl!lln Isee map I StS of two d ffcrent londfarms the modern Salt R .er beel or t he act.e geologiC floodpl,lIn and the Le hl Terrace conSlstlnp of alluvml tp-rrlcer ill ong butll sdtlli 01 the lIver The leh l Terrace surfaces are about 5 feet (1 6 ml abo"e th e present nver bed Isee GI 2 D for (I mnrc r mnpl! te I of tllese two land lurrli!» Pre-1891 floods Arc hooluglGal alld geological stud es reveal that great floods occurred along the Salt River for millen ums probably were larger theln 1:Iny rt:lcordl:ld f1ll:;tuTII.;i:l 1 fluou Tile Hohokam Ind a ns had an extens ve Irt gatlon system which they abandoned at least 500 y, ilgU (19761 and Woodbu ry (1960) rn dlcate that anCient Indian canals along bot h of the modem Salt River on the lehl TtJ rrace near PuelJlo GTande 11I6th Stleet at Washington Street In Phoen x) are now bl rlerJ hy s IT and Iflm natp.d sands (Fig 11 These flU Vial sedi ments are eViden ce that great floods occurred dur ng the last SOO yeers and posslhly dUrinG the II .. t 1500 al onll tile Sail Rver lI1undat ng tha Leh Terrace Some of the bUried Indian canals studied were OUtslc1C nnd <lho..,e the ;mm thoullht to h<l vr' been Ilundated by the 1891 flood 4 Meiers Figure 1 A tVPlcal cross of a Huhukum canal filled by SIlt and lam- mated sand showmg d'pIJ!;tl, {rom seueral {loads Fl UVial tl epcslts of the ler ra ces adjacent to tha present Sa lt River bed (sea the GeologiC map GI2 A)lndlc (l te great floods h<lve occurred In th iS I/alley the lost 1'.\0 million years Floods for apprOlllmately the last 20 000 yeats have been restricted to t he \jeolu\j!G fiuodpl(ilfl ur tile mUUtH I Sail RI\el betl and the Lehl Terrace H stotlcal references to floods on the Salt and GIlt! RIVers from the McDowell Dam 5 te Imouth of Verde River) to Gillespie Dam 48 m les (77 kml downstream from PhoeniX extends back to 1833 b ut uf du;{.;har\jtl are fur orlly t ht:; J,l enoC lasS to da te H SlOr cal re cords Ind cate that prior to 1 891 general flnod .. occ urred In t833 1862 1869 1880 lB84 1886 1009 and 1890 The floods of 1B84 and 1890 were almost comparable to thc 1 891 flood (U S Arrny uf 1957) Twen tie th century floods Because there have been many floods recorded dunng the 20th century one should not th ink t hat there has been an ncrC<lSO In the r<llr. of flolld ng nf the Tempe Qundrangle Rather the method of record ng has Improved and all floodflow'S are now being measured Pnor to 1 911 Pr or to the comp letion of the Roosevelt Dam n 1911 records ellist for two very larye floods which occurred the 1891 flood descr bed abo\a and another In 1905 (Table 1) Both flooded much of rhe Snit Rlvcr V.IIII y lnd clIused dam<lgt:; to cill struct ures of that time The November 1905 floodflo", was more than 200 000 r.fs 15e63 cmsl me(isur!:ld makmg It a 75 ve ar flood After 1911 Table 1, Significant flows of the Lower Salt River- Date Feb 1891 Apr 1905 Nov 1905 Jan 1916 Jan 1916 Feb 1920 Mar 1938 Mar 1941 Dec 1965 Feb 1973 Mar 1978 Dec 197B Jan 1979 Mar 1979 Feb 1960 Dec 1982 Oct 1963 Flood Peak Flow (measured at Granite Reefl 300 000 (est ) 115000 200 000 120000 102000 130000 99000 40,000 67000 22 000 122 000 140000 BB 000 67 400 100000 25 000 45 oM (emsl 8496 3257 5664 3398 2889 36112 2603 1132 1897 6Zl 3455 3965 24"" 1909 5098 708 1275 Recurrence Interval yeAr flnnrJ + 200 13 75 " 11 16 10 , 8 4 " 20 , B 55 4 5 'Aldridge, 1970 w lltten commun Feb 21 1984, Reigle Dallas Senior Hydrologi st Salt River Pro]1 r t wntten cummun May 23 1984 D S Wi lson Jr Manager WAter Resource Operations Salt River Project + Regulatad discharges for present cond nons from Central Arl70n J water control study 1982 USA Corps of Engineers Sillce water storage behind Roosevelt Dam began In 1911 and Nl th ln the ot her five wh ch were suuselluerilly I.:o rlst uctad there have been 17 floodt l ows ITable 1) They occurred from 1 month t il 24 years apart and rangt:;d In rnalJ rllludtl frurn 22 000 cis (623 cms) a 4 year statistIcal flood to 180 000 cfs (5098 cmsl n 55 yea rflooo Thc In undated by I.:€rta lll large tloods are shown on the map With !In ncrease In population 10 the Tempe QIJlldrangle and settlement and development of more ot the floodplain each large flood can be expected to be more damagi ng and dlsruptlvp- Tht, DecernLltlr 19781100d outli ned on the map c[lused damages along the entire Sa lt River le ngth which were estimated to be $38,956,000 and Clbout 33% Ilf that was esti mated to ha v1::l UeI:Hl Iflcome lost because of traffiC delays (Corps of Engineers 197!)cl The February 1980 flooc1 ",1[,0 outlil1t:;d uti Gaused damages estimated to be $63 700 000 (Corps of Engineers W81 f Future floods A great flood Inundotmg th,' geolOYlc lIoodpl am of the Sat! Rver IS pOSSible at any ltme 1 he geologiC floodplain IS t hat area shown on the map as the Modern Sellt Rlv{'r bed plus the l ehl TerrdGe Sudl a floodllow mi ght exceed 300 000 cfs (6495 ems) which s thAt of the 200 year flood mc I urI rJ 111 tim Tempe Blidge Since the SRP dams have been bUilt 74 years ago there have been no 100 year floodflow s through t im Tempe Quadl angle There h<lvtJ ul;leu 110wever floods With n the watersheds above the dams for whIch the flows probably eKcecded t hat of thl:l 100 yl;I8 r Ilood at a given measunng POint (Aldridge 1979) CalculatIOns by Aldndne anc! EychHner 119A2f Ihil t w thout the SRP dams In plll( P. II e March 1978 and the December 1978 Salt Rl verfloods would have been OXTmmely larOe floW!'!. thtflllgh the Tempe Quatlr<lIIy la lesultlng In mallimu m floodf l ow of 260 000 c15 (1363 cms) spilling across Gran te Reef DAm wh c h s the f low of il 140 year flood ll2 I ,I '7'3 C )" f-- II ANCIENT INDIAN CANALS BURIED BY SALT RIVER FLOOD SEDIMENTS APPROXIMATE LIMIT OF 1891 SALT RIVER FLOOD Flood control HM floml mllnagemellt such as reservOirs levees and channeliza tlon prOjects may prOVide flood protection for mHny But flood pruttlC t un can seltlom be complete There IS always a probab Illy that a greater fl ood Will occur than hflg been ex penenced In rccordcd hl[,1:ory However, such a great flood would be restncted to the modern geologiC floodplain BASE MAP FROM U S GEOLOGICAL SURVEY TOPOG RAP HIC MAP 1 24 OOIJ ::;:IERIES Thr. question IS often rdlti!:ld cOllcernlllg the area t hat would be flooded If one or more of the dam9 on the Salt nnd Vcrdc Rivers were to fa ll w th at lull capacity Sud I a tiCBnariO s conSidered In a 1984 publlcetlon by the U S BUrOal 1 nf Rccl l mat lon and briefly summarized here for thc TernJ,le Quadrangle If only Stewart Mountalll Dam were to fal l the flood In the Tempe QU8c1ra ngle wlluld be re.,tm;ted to alJouL tile modem geologiC floodplain equal to about 150 000 to 180 000 cfs 14248 cms to 5097 emsi In a worst case scenario wh ere all dllfTI5 fall little water would go north of th e ri ver bed but the ent re Tempe Quadrangle south of the ellcept f or bcdrm k 1 1I ghlal would be lIoode d TEMPE. OLJADRANGLE (1952 PHOTOREV ISE D 1967) Additional revIsions compiled by the Geological Survr.y from aer al photograpll!> takt:ltl 1978 and other sources ThiS Informst on not field checked MlIp edrt!:ld 1962 U·M D AND 1981 !>.'!AGNEr C NC R IH C:C.INATION AT C' S"EE- SELECTED REFERENCES Aldrld!1e B N of Novelnbe r 1975 to January 1966 III the Gila R vet BaSin Arizona and New Me)(lco and adlaccnt baSinS n Amun .. Umted Stat es Geological Survey Water Supply Paper 1850-C 179p Aldridge B N and Eychaner J H 1982 01 Odooor 1977 In Southern Arizona and March 1978 In Central Un ted States GeolO!]!cal Surv ey Opcn Fill Rilport B2687 167p Altlrldge B N and Hales T A ,1984 Floodsof November 1978to Morch 1979 In Ar zonil and west ccnlfil l NtlVII Meltlco Umted States Geological Survey Water Supply Paper 2241 149 P Beard L R 1962 C<l l methods n hydrol ogy Un ted States Army Corps of En gl nears 62p City of PhoeniX En!]lneenn[J Dop.'lrtmcnt 1974 Floodplain wat!:lr SurlaG9 elevatIOns 13p City rl f Tempc 1900 City CounCil Floodplain Ordinance 828 2 7p Dalrymple T 1960 Flood freque ncy United States Geological Survl:lY, Wal !:lr Supply Paper 154J.-A 80p Flood Insurance Admin istration 1976 Flnodplaln Insurance of Sl.:otltidale alld Indian Bend Wash 24 maps Kenny Ray In press Fl oodi ng In Pcwc T l Getlloglc of A rI.<o na SpeCIa l Paper Number 4 Bureau of Geol ogy and Minerai Technology Tucson Masse W B 1976 Huhok 1m Project A study of preh stOTIC mgatlon In the Sat! Rver Valle\ Anzona AnZOM Stme Museum Tucson 88p Pevle T l 1978 Terracc" of the lower S(ilt Rver Valley III relatl cn to the late CenOWlc hls·ory of the Phoen iX Besln In Gu debook to tht:t geGlugy uf Central Arzuna Burt D M and PeNe T L eds SpeCial Paper Number 2 BureOll of Geology end Mlnerol Technology ArI<: on a p 1 45 PI w{ T l 1982 GeologIC hazards of the Fa rbanks erea Alaska Dll/lSl On nf Gr.1l10glC'n1 1 end Geoph\'sr.<l1 Stille of Alaska !jpecl al Report 15 l09p Pewa T l Wt:llltJrldOI I C 5 and Bales J T 19S6 Env ronmp.ntAI geology of hc Tempe Qllac1r mg ltl Countv Arizona - Geology Uureau of GeolO!=lY end Minerai Technology TUC9011 Ar zona Geolnglt 011 Senes Map GI 2 A SalT River Project undated Major 111 ullef about t ile Salt River Pro ject 40p Umted States Atmy Corps of Engmeers 1957 Interim report on survey fo r flooc1 control Gila alltl Salt Rivers GlliesPle Oam to M cDowell Dam Site Arizona 54p \o\ lth ap pend ceg Umt! d Army COlPS of Eng neers 1972 Report on the Flood of 22 J u ne 1972 In Phoemx Metropolitan Aren Am :ooa 55p United States Atmy Cnrfl!1 Ilf Eng nr.crs 1975 Indian Br.nd Wasn dr.slgn memorandum I general deSign memorandum phase II 80p Unltoo Stales Army Corps of En!=)lnoors 1977 Summary report for flom] ( untrul G la Floodway ManGopa and Pilla! Count es Arizona 14p United St ates Army Corps of Engmeers 1979a Flood c1amngc r1'port 28 February 6 March 1978 Maflcopa Counly, Arizona 3Bp United States Anny Corps of Engineers 1979b Dtoft plrln formation appendlll Phoen Il study F nill Rtlport 101p Umtl:ld State!> Army Corps of Elg lneers 1979c Flood dsmagll report Phocni ll Mctropcll tan Area Deccmher 1978 Flood 41p Unrtcd Army Corps of EIlglneers 1981a Phoen II flood damage survey February 1980 29p Umttd States Army Corps of Engineers 19B 1b Sa lt and Gila R I/er 1 01 Central A rlzonil Water Control Siudy 14p UllIted States Ar my Corps of Engmeers 19S2 Central Anzona Water Control Study Gila River ond Tr bU tllfltlH hydrology 43p United States Army Corps of Eng ineers Bureau of Rflr.lamat lon 1979a Dr,,1t reCO linalS report and plan of study tor a study of the fo r Salt GilD flood con tro l and regulotlnn of Centr II Anzmlil Project wate rs 113p Un ted Sla t l:lS Army COlPS of Engilleets Bureau of Reclamation 1979h Plan of study (draft) Central A rizona water contro l study 87p United Sl.<lteti Bureau of Reclamat on 1984 Salt River Project Amona Flood boundilry scenArio de!lcnptlon 12 sheets United Slates Department of HOUSing and Urban Development 197B release number 78 1 12p Un Led States Geological Survey 1969 Map of flo od prone m (l<lS Tr.mpe Quadrangle Arizona, 7'h mlnuttl 1 Wellend orf C S Bales J T cmd P ewa T l 1986 EnVironmentAl genlogy of the Tempe Quadrangle Maricopa Cour ty Arl<:l)lIa - Landforms Bureau of Geolo('1\ and Minerai TechnolCiJY Tucson An70nfl (;r nloglf Sar es Map GI 2 D Woodbury R B 196[) Thr. Hohokam ean1:lls at PUl;lblo Grande Anzona Amencan An t qUlty volume 26 number 2 p 267270 ' 11 MODERN GEOLOGIC FLOODPLAIN INCLUDES MODERN SALT RIVER ' 16 FE!:.I z o 111"5230' T 2 N BED (ACTIVE GEOLOGIC FLOOD- PLAIN) AND LEHI TERRACE !!"'I_oI APPROXIMA-T-E ;;'L-IM-IT-O-F--.li.---· --- 31 I o •• - .' tOO) lWJ LLT CONT OUR INT ERVAl 10 FE ET OATUM IS S EA LE"E Sail Rjver III (Iooo sraf{1? al Tempe Bfldgl? Febmory, !9fW Fro)\; oj 180000 w/m; jeel pel sec O!ld 15 f(lr"l:'sl UI Ille IHel 5111ce 1905 a! d represe/ls the 55 )ear f700d (f>h()[()grapl1 "10 4502 h} TrU\ L P/>w/>, FI'/' 16 19110) The <1rprecatr.d the revl8w 01 the ungmal (1980) I/er s on of th s text and map bv Vol H Worthl n\1ton Pyk, lInd Alln Chin uf the U!j Army Corps of Eng neers PhoeniX Ar zone ano D E WomAr.k ErJ b Klrdar 0 S Wilson Jr and T T Wilson of the Salt Rver Project PhoeniX Arizo na "Ie DEC, 1978 SALT RIVER FLOOD •••••••••••• ••••••••• T1N APPROXIMATE LIMIT OF 1965 - 66 SALT RIVER FLOOD ----- -- ---- T I' rCWN to 7 IVI E 33 Q 22 111 Q 5230" So u rce of f lood olltl 1891 - US GeoloQlcal Su rvey Map 1969 Wit h m oo lf l r. ntlons fr om doro In Southern PaCifiC Tempe Railroad Ur dge plans 1965 66 - P6we Ilnflub ll r hr d diltil 1978 - Corps of Engilleers 1979c 1980 - Atlr al (A r £(lIl a Depa rt of Transpottat lon) TllrhuMnl RI er 1/ fluud neur I!nd ()( flWl1'a y oj SA. j. HmbO! AlfpOJ/ Phon I). III Jail /U'r} /9 7 9 Abour 2500 feet of mrporl runway "'as away III Iht rlYtr I Lfo'Vlltd beilleefl the IWI1\ay alld mdustllal sites 011 thesollih of the nver Phorograpl1 a 40111 Street lookrnf!, north \then f/w'r wal nm nmg 72,000 (ub" per sewm) (P!IO'Qgluph i'\Io 4J52 by T L Ptwe, Jan 19, 1979)
