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<br />canyon reOl.chr-s al,o Jued ;)s sur.tt'rranr-an dams,
<br />undt"rground Il'lw of water WJ.S forct"d to tht: sudan,'
<br />crt'alln,c rdl.lhlt- rt"aches of srrt".lm. t"\'t"n dUfln~
<br />drought
<br />Tht"St" lMge dt'sert fI"r-rs ag;..:raded th("lr \',dkys
<br />except In tune ot channel-suJI~htt:[IlnJ.' tlo(j,j
<br />Sur.suatt"s 01 sand ;lnJ lIne ,craHI shlf[t"d
<br />conrinUlJU51y with [ht: currenL In rt"Jdlt"s Ilowlng
<br />throu,ch \'.dJeys. pouls werl: formnl by Jt.,craJ>ltlUn
<br />on [hI: uutslde of mt"andt"rs .H hy unJerCuttln.L; of
<br />flp:Htan trt"t"5, llr were assoCl.Hed with brge IllgS ur
<br />other Jf:hfls In {ht" ch,mnds Pt:rm.lnt"nr fe.Hurt"s such
<br />J.S r.(luldf:rs llr irr("Fularl[lt's In stony \\'Jlls 01 t:JnYllns
<br />caust"d S'llUr. anJ Jr-ep plat'~s perslslt"J Jt"Spitt"
<br />conunuous beJlo.ld trJnsport.
<br />\\'a[t'r tjUJ!ity \.Hll:U rJdlc.dly ~nowmelt proJUlt'J
<br />water II)" In lOul dlssoln:d solids. \\'Iult-
<br />e..-apotranspira[lOn In summer .Ind mtlllws uf
<br />mmer.dllt"d spflnp pcmnort:J htgh s.lhnmes. :h Jn
<br />examplt. of the last, reSidents near Yum,1 rr-portr-dl~'
<br />Impounded .I 10" t10w of the GdJ RJ\ t"r m-u the
<br />turn of tbt" ct"nrury to pre\'ent coor,lmlnallon of
<br />Jtlwnsrream Irrig>ltlOn supplies b~. "Jlka!J W;ltt'f" A
<br />small flood In the Gila br\""ch~J the Jike .lOd [\lXll
<br />W.l[er flllW~d lnw thr- Colorad,l RI\TC malnsrre.lm.
<br />supposr-dl~. kdllng flsht.s ftlr .1 distance of mnCt" than
<br />160 km, all tht" way from Yum,1 to dle Gulf Ilf
<br />CA!J(ornt,L
<br />TempNarurts also must IUH: Ilu..;tuareJ radically.
<br />yet r-xtremely IUf:h water tempt"r.Ltures Iikdy did nm
<br />occur Det:aUst' or e\':.LpOratHln Into the dry dr-st'rt ,llr.
<br />Dant:erllusl~' hi!!h watt'f tempt"r.HUrt'S can de\"e1op.
<br />howt'n'L when d;lrk sur.str,ltes b.lck r.lJI.Itr- ht'at lOW
<br />deJ.r. overlpn~ ....atr-r. or. .lS norr-d hd"orc when
<br />unusually hl~h humiJlttes suppres~ e\'.lpOr.ltl\ln (tllm
<br />.....ater sur!Jce~. C:lnyon segments rt'malned (uoll'r
<br />SIOt:C stony WJlls sh,IJed [Ot. stream and e\'.lporatlOn
<br />resultc.J In e\'en more raplJ co.1Iint:: ....hen dlre(!
<br />sunllgh[ was excluded.
<br />The IO....t"cml)s! ponHlns of re~1<.)n.d rln:rs
<br />ori~lnallr conSISted uf IJr,e.e. ~,lnd"b()tt()med dunncls
<br />meanJeftng onr btllAd delt,ls (Ftt:: ')6). \\'.I{er llO
<br />undisturhed deltas must h.lve r.een se,lsllnalIy .....arm.
<br />slit laden, ,lneJ ftch In organlC debfts tr.lnspont"d
<br />from thc"a \"J.st watersheds. Somr- .....ert' hned r.~.
<br />dense ftF'.HI.\n wooJLinds (FIt:. 5":'1. forests llf
<br />c(ltronwoods anJ willows ,\nd unJerStlHleS (Jf
<br />J.rwwweeJ" seepwillow, and other wooJ~' plants.
<br />DclulC ch,lOnels wet(: so broad, howt"H"r, th.ll only J.
<br />sm.lll F'er(l:nrJ~e could ha\t' been ~hJ.ded from
<br />tntense summer sunh~ht. R~lCks and houlders llf
<br />hr-aJwatt:rs h.ld I\lng bd"nre r.t'en t:round tll fIner
<br />pundes, ,md ,IKCr,ldatlon of stlt Jnd sJnd \\JS tht.
<br />rule except at the hl,C.hest t10v. Or~,101c materlJls
<br />artlnng on Jdtas alsLl h.lJ Dr-en puln'rlzeeJ; en:n
<br />
<br />
<br />Figure 56 View of Ihe Colorado River Delta soulhward lrom
<br />near the Inlernatlonal Boundary In 1975, ThiS vast and
<br />complex region has now been largely deSiccated as a result
<br />of water diversions and deplellons upslream. Pholograph
<br />prOVided by the U.S, Bureau 01 ReclamatIon.
<br />
<br />J'lgs waslllng ttllm milLlntJIO fort"sts were mostly
<br />reJuc~J to ml(rllscoplC particles ur actually dlssoln-J
<br />r.r-foce nr-;HIO~ tht" se,t Dlssnlvt.d ;lnd p.lniculAtt"
<br />orgJrlIc m;lterlJI pTlwldl"J tendiling nutftenrs not
<br />only for deltaiC CllmmUnl[les. but :ilso t'or [h(" Gulf nf
<br />CalifornLI Impacts of entr.lpmt.nt of thesl- nutrtenrs
<br />b... upstrr-;Im rt"St'r\.tllrs on thr- r-colot,:y of the gulf has
<br />ne\'u r.een assl.sSt.J,
<br />Rcmarkablt, \,;lft.l[llln In JlsthJr}.:t' was the rule.
<br />\\'Jter spre.lJ Widely U'"l"r the hrl)ad. nt"OHly level
<br />11oodplatn. JnJ Nth fl.lod resulted 10 chJnnel
<br />ch,lnFes. OxDn.... I.lkes .lI1d slou,.:hs wert' fMffied. only
<br />t<l hr- Illlt"J with tlrg.lnlC .\nd InurganJC dcbfls duftn,.:
<br />pt"rlOJs of low dlslhar,Ce. then cut ;IFJln by laa"r
<br />fllllldJn~ en.ms. TillS WJS espr-Clally trUt. where stlft
<br />ddt.i1c st..dtmt'm~ W("rt" ffi.lrkt.J by cllmplt.x series of
<br />Sprt';lJtn.l: ch,lnnels \It dlsuir.utarir-s tFIF. 56),
<br />Channels wt:rc ,reJrt.J .\Od dISapl'e.lre~1 In Jay... or
<br />hours. A~rJJ,ltlLln formed nJ.tlHJ! levees and bkts,
<br />
<br />Figure 57 Riparian WOOdland on the COlorado River Delta,
<br />ca 1890. Photograph prOVided by R D, Ohman.
<br />
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