Geology and ground-water resources of the Wellton-Mohawk area, Yuma County, Arizona

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CONTENTS
Introduction . • . . . . .
PU~ose and eooperation
Location .... : '. .'. . '. '. . . .. .
Clim?te . . . . ... . .
. History of: development .....••
Previous investigatio'ns
Geology.and its relation to ground water
Haps and field '",ork . . • • . .
,Geologic history • • ••
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. . .,'
Structural (;eology . •. . • • . • ••
St rat igraphy • . • . • • . . . . . .'
Metamorphic rocks (pre-Cambrian?) •.••
. Igneous rocks . . . . . • . •
· .
.·
· . Pre-Cambrlan( ?) granite . •• • • .• ���..
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.. .. . , · . · .' .
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· . · .. .' .. .
· . . \ )' · . . -- · , . , . \ -, · . . .
• •
Cretaceous(?) and Tertiary volcanic rocks . I. .
Q;uaternary . (?) basalt s . . '. .. . . . · . . · . . Sedimentary rocks . . •• .••• , .
Pre-Tertiary (?) rocks •. .•..• . . . . . · .,
Tertiary (?)rocks. • •••
Q;uaterpary and Tertiary alluvium I. • • •
Older alluvial ·£i11 . . • • .
Younger alluvial fill . • , . . . .
Ground-,",aterresources... . • . . . • • • . . . •
Occurrence of ground water . • • .• • •
Rech~rge • /I • ,; • • • • • • • • • •
Stream flow • . . . •
Irrigation. .•• .• • • . . • • • • .
Underflow . . . •• .,. •.•
Rainfall . . • . • ...
Movement of ground water . .
Discharge . . . . . . . •
"t'l.... !
.r; u.T!),:1;)ag e '!'. • .. • , • • •
NatiJ.ra1 di scharge • • . • •
Fluctuation of the water table • . • .
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~ali tyof water . . . . • . '. . . . • • . ._
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Chemical· charact er of ground "rat er • • • • •
·· .. .. ·. ., · . . . · . . ·.. ... ..
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. Relation of quality of water to use •• • • • ••. ' ••
lIrrigatian . . . . . . . . . . . . . ....
Domestic luse • • • .~ • • • ~ • • • • . .. • • • • • • ., • •
Relation of quality of water to recharge and source of dissolved
solids in ground water . • • . • . • • • • •• • • ••
Discharge of dissolved solids from the area .••• f ' •• , ••• ,1,0:.
SummarY' and conclusions . . • • . . • • 1/ • • • t ' , • • •
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TABLES
Record.s 'of typi'ciul well s, Wellton-l1oha1"k area:' Y'mna 'County,
Arizona. '.,.', ".,:.' I'.". " "". ' ..... 'l'. , ..... '. ' •• '. " •• " ••••• ...
Logs of typical,1",ells, ,Well ton-Moha,,,k'area ,YUma County t Arizona
Analyses of ,water (rom 'typicial '~ells f~ Wellton-Mohawk area,
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Yuma County. .Ad zona' • • . '. . • • • • . . . . '. '. • •• 22
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ILLUSTRAT IONS
Plate 1. Map o'f .Wellton-Mohawk area, Yuma County, Arizona, showlng
geology,. locations of wells used for irrigation and water-level
observatlon, irrigated areas, and contours of the ,water table as
ofl'ebruary 1946. , '
2. Hap of Wellton-Mohawk area, Yuma County, .Arizona; sho"ring mlneral
content' of groundwater. ..
Figure 1. I • Idealized section of valley fill. Wellton-Mohawk area, Yuma .County,
Arizona.
2. Graphs showing fluctuation of water level in typical observation
wells, and the changes in dissolved solids, Wellton-~otlalr1'k area,
Yuma County, Arizona.
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lliTRODUCTION
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PurE9~d cooperation
'!he rapid depletion of the ground-water'resources of Arizona during
the past forr years has called attention to tho need for State regulation
of thes~ resouroes. , H01;levor, as such.control must be bast1d 011 adequate
information as to quality" quantity, soure,e, and movement of the ground
wayer, the ,Arizona State Legislature 'in 1945 apJ;ll'opriated funds for the
investigation of the important ground-nater bas illS in the :;;tate ~ 'Ine
work done ,in the ·;Jellton ... Mohe.~1k urea was performed as a part of this
State-wide program. The work VIas done on a cooperative basis bet1'1oen
the Arizona State Land Department, O. G. :'!illiams, Conmlissiol'l.or, and
the United States Geological SUrvey, Department of'the Interior. Field
\70rk i)1 the Vlellton-Mohauk area \'tas performed by H. M. Babcocl~ and
A. M. Sourdry, engineers; and by S. C. Erei'm, G. J. Hazen, and
C. T. Snyder, geologists, under ith~ direct suporvision of S. F. Turner,
District EngineClr (Ground \1ator), of the Federal Geological Survey.
Watcr analysesnerC made by J~ D. Hem and R. T. Kisor, chemists, under
the general direction of C. S. Honard, Pi,strict Chemist of the
Geological,SUrvey.
Location
The \Tallton-Mohallk area is"-atiido-: flat dosert :013in that extends'
from thel torm of Domo upstream along the Gila River for a distance of ,
about 40 miles. This' araais, composed O:l tho' Viall ton Nalley on the
uest and of the northern part of the lv'I'..ohm71: Valley on tho. cast.
These tno, valleys are" partially soparatod by the CopporN.!Ountains,
Baker Poaks, and .Antolope HilL 'Ihe area is bounded on the east by the
Moha't7k Mountains; on the wostby the Gila Mountains; on tho north by
tho W.tUggins and ,Castle Dome Mountains; and on the south by the \7cllton ,!
Hills, tho Copper Mountains, and by an arbitrary line extending
northeast from tho CopporMountains across the Mohawk Valley to the
to'lim of Mohawk. ,fue area lies entirely \7i thin Yuma County and, covers
about 709, squaro miles.
Q1..J_ll!§ t e_
The l.7elltol1-Mop.atlk area has a climate fcharacterized bymild
rlinters and ho'b~ dry summers. The average preCipitation is 4.43 inchos
a year at 140havlk, according to a 43-year record of the U. S., Vleathor
Bureau. The temperature ranged fr,om 280 ]'. to 1180 F. durinG,1945.
The mean annual temperature at MohaTIl( is '74.2° F. and the frost-:C:rce
season is more than 11 months.
H~~T~5?.rL of, dC~):~.9pmollt "
The accounts of early explorers and of old settlors still livinG
in the area indicate that the Gila River has changed materially'slnea
it first TIas seen by 'white~ men. .At Olle timethc river contained
suffieidnt surface water for irrigation and sUPl1ortod a lm.'. Uriant '
grm7th of GOi;to?:lwood and willo\1 trees· along, its bl:ml:s. At tho 'l')rosont
timo(194G) t.hc.:.'e is no 'Hater for irrigation from surface flor! ct tho
rj"er, e.nd the large groves of cottorii1ood and willorT have h:;OIl roplaced
by less lu)..'Uriallt arrow weed alld se.lt cedar.. VIator now floVlS in '~hG
ri vor only tor short periods afta l' intrequent J heav;( local rainstorms.
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The earliest agricultural development by \7hi te settlers in the area
took place in conjunction \7i th the establishment of the stat ions that
served the early overland stage lines. 'The first stage line \1aS
established in 185711 and folloiled the Gila River from Fort Yuma to
Sacaton, a distance of about 190 miles. Intermittent irrigcltion
development, with the fo:rrno.tiol1 of severalcanal,companies, continued in
the area until 1905, when a disastrous flood on~heGila River washed ,
out most of the canals and canal headings. Several subsequent
unsuccessful attempts have 'Qeen made' to use the surfc:\ce florl of the
Gila River'for irri~ation, but the increased diversions of water for
irrigation in the upper reaches of the Gila and Salt rivers have'left
progressively less surface nator for Use in the ~,'[ellton-Mohawk area.
As a result, 'farmers have developed more and more ground water for
irrigation. About 7,000 acres of land was under cultivation in 1946,
the water for all of which WaS derived from ileUs. Plate 1 sho\78 the
cultivated areas and the locations of all irrigation 1"/ells. Table 1
contains records Of typicaluells in the area. '\ .
Pl:ClY~101l.~_~.J:lY.~E..~.iJ.<;~~:Loll.§..
Earlier studies/of tho geology and ground-uater,rcsourceG of the
v7ellton-Mohm7k aroa are described in tho follouing reports:
1. Ross, C. P., Routes to desert uatol'ing places in the 10rter,Gila
region, Ariz.: U. S. Geol. Survey Hater-Supply Paper 490-c, pp. 271':
315, 1922.'
2. Bryan, 1\ir1::, Routes to desort 'I1atoril.1g places in the Papago
oountry, Ariz.: U. S. Gool. Survey Water-&~pplY Paper 490-D, Jp. 317-
429, 1922.
3. Ross, C. P., 'The 10\1er Gila ctegion, Ariz., a geographic,
geologic, and hydrologic reconnaissance, \7ith a guido' to desert
watering pla,cos: U. S. Goal. S!lrvey \7ater-Supply Paper 498, 1923.
,4. Bryan, Kirll;, Tho P8.pago country, Ariz' j a f;:;ographic,
geologic, and hydrologic reconnaissance, ili th a guide ::jO do sort
wa torj ng plac os: U. S. GGol. Survey Via ter-Supply Papcl' 49~, 1925.,
·5. Ylater levels and artosian pressure in obsorvation wellS in
the United States, l)art 6, Southncstorn states. and Territory of
Rauaii, calondar year 1945:· U. S. Geol. Survoy water-supply paper
in preparation.
, 6. Viils01l1 E. D., Geology and mineral deposits of southern Yllm!3-
County, ,Ariz.: Ariz. Bur. Mincs, Gool. Ser.No • .7, Bull. 134, .1933.
GEOLOGY AND ITS REUTION TO GROUND 7lAT.IliR
~.Pi.9}l.c!.1..~~J,"~.EE_r It
Field work in tho \"loll ton-llIohal7k 0.1'00. tias done from February to . . I
April 1946. Because of' tho limited time availablo tho 'Ilork 17as planned'
to be of roconnaissanco nature, and theroforo no attempt U8S made to
map tho 'goology of tho aroa in'detail. Tho goology \las mapped directly
on tcpographic 'rr..aps o~ the U. S~ Geological Survey. Geological field'
VTork \las divided as folloV1S: tho t:uggil1s and Laguna Mountains by
G. E.' Hazen; the Moharlk and Castle Dome Mountains by C. '1\ Snydor; and
the Gila and' Copper Mountains, Baker Peaks, and Wellton Hills by
S. C. Brown. The areal geology is ,shoun on plate, l.An idealized
section of the valley fill is shoun in figure,l.
rr~ ,
'Ross, C.' P., 'The lower ,Gila region, Arizona, a geographic, geologiC,
and hydrologic reconnaissance, with a 3uide to desert watering
places:, U. S. Geol. Survey Ylatcr-SuPDly Papor 498, p.9.7, 1923.
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~€iic_.h.istory" I
The geelegic histery during pre-CambriE).n time is obscure because
the rocks have been highly metamorphosed and er.oded. It is evident,
however, that these metamerphic rocks are .of beth sedimentary and
igneous .origin.
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Srnall,'isolated outcrops of boulder conglomerate of possible "
Mesozoic age occur in the Gila and.1fru.ggins Mountains~ Th.is indicates
that the Mesozoic deposits have been largely removed by erosion or that
the depesitien was on a minor scale.
The end o'f the Mesozeic era and the begj.nning of the Cenozoic era
were marked by intense faul tins and v.olcanism. The faulting pl'obably
produced the present-day, northuest-trending mountain ranges. The.
volcanism resulted in the depesition'of several hundred feet of
agglomerates, tuffs, and lavas. Late in Tertiary time the troughs
betneen the mountain l'anges v/ere partly filled "ith boulder c.ongl.omorate
and lake beds. Some .of the Tertiary t'?) sodimentary rocks appear to
have been deposited on lund, and uidespread lake beds indicate that
playas or sha11.o\1 lakes existed over large parts of tho· area.
General uplift apparently marked the beginning of Q,uaternary
time. Alternatlngdeposition and d.orm:.cutting in the basin :pr.oduced
tho present-day terraces (seo pl. 1). Soma velcanism'teek place
simUltaneeusly with the later uplifting, although italJparontly uas on
n minor scale in comparison te th,G velcanisrll .of the, Tertiary and
Cl'etaceous time. .At tho present time the Gila River is aggrading
within the area, and the channel is being filled \71th fino silts and
sands. .
, • §EJ'_1.!E_t~_¥_£.~_~lo& ,
The '~,1ellton-Mohankarea is a part of two no:rth17cst-trending
structural ,basins that wore i'ormedby block faulting. 'rho major faults,
uhich prebablyparallel the main meuntain rangos, aro coverod by valley
rill of Tertiary and ~uatornary ago.
The first peri.od of major faulting and felding pr.obably took
placo during pre-Cambrian time, and produced the highly c.ontorted
motamorphic roc1cs exposed in tho mountains. The sec.ond period of major
faulting andfelding eccurrod at the end .of the Cretaceous peried and
the beginning of l,tho Tertiary peried. This faulting probably produced
the present-day, nerth~Gst-tl'ending mountain ranges, and tho major
faults have a general N. 250 11. 'strike. Faulting an4 folding centinued
intermittently, en a diminished scalo, through tho Tertiary into tlle
Quaternary period. Th.is is indicated by tho displucement of tho older
alluvium al.ongfaults on'the east and northeast sides .01;: tho Mi.J.ggins
Mount~ins and by displacement'of the Q.uaternary (1) basalt by fuults
in tho Castlo Dome :Mountains. There aro tne distinct sots .of faults
in thoset'l10 meuntain ranges with gonel'al N. 65° VI. and lI. 55° E.
strikes, respectivel~r.,
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1futamorphic rocks (pre-Cambrian?)
Gneiss is the most common metamorphic rock exposed in the area.
It is tentatively regarded as pre-Camprian in age. 'This gl:eiss, where
observed,. appears to be metamorphosed granitic rock as in places it
grades into granite.
. Tv70 distinct types of schist were observed in the area, one of
sedimenturyorigin and the other of igneous origin. Both tY!les are
considered .to be pre",Cambrian in age ~ A narrou zohe of schist at the
north end of the Gila Mountains is composed of metamorphosed sedi­mentary
rocks. It con~ains marbles and slates, which are alte::.'ed
limestones and shales, respectively. BetT16en the Copper Mountains and
Bakel;' Peaks is a zone of gently dipping, medium gray schist of probable
sedimentary origin. Schist of sedimentary ori~inis also exposeo. on
the east end· of the Laguna MaUll tains and on" the i7C st and northi/0st
sides of the NlUggins . MO\ulta ins ~ .All other 6.chist obsorved in the area
is composed of metamorphosed granitic rocks.' .
No .wells, springs, or natural tanks \7erO observed or reported in'
the metamorphic rocks.
Igneous rocks
-Pr-e-Cambrian(?) granite -,--.--.~--
fJ;\70 distinct typos o'j.'granito ttv>r0 obsorved in ·tho Gila
. Mountains. The most abundant type is a light gray' to \7hi to, modium
ta- very coarse-grained, massive granite. It weathers to a light
brown to buff color. Silnilar granite rras observed in the' southern
halr of the Copper Mountains. .
Near th~ northorn end of tho Gila Mountains is an intrusion of
highly decomposed, epidotized grani to porphyry. It bas a medium gray
. color on a fresh fracture and ueathers grayish bronn. It disintogrates
readily by weathoring and breaks up into large, 'lrlOll-rounded boulders.
The true age of the grf,lnito isproblemutical, as no detailed
studios have boen made. It is tentativoly regarded as pre":Cnmbrian
in' age; hovlOyer. Viilsor&! states it may be as late as Iv:Osozoic or
Tertiary. . , ,
No wells or springs nero observed or reported in those granitos •
.A fen perennial naturalte.nks arc reported in the higher mountains.
/'
CFe_~.~co_ous (?). an<t.1.~r._t~'y~_volcalli£. rocks. '. . .
Viidospread areas of volcanic roclcs of Cretaceous (?) and Tortiary
age: 'are exposed in tho Laguna, Muggins, and Castlo DOlno momttains;
The rocks consist of several hundred feet of flat··lying to gently­dipping,
well-stratified tuffs,'. breCCias, agglomerates, al1.d le,vo. 1'10\75 •.
In tho :Muggins Mountains a section of tho older volcanic rocks
was estimated to be more than 1,000 feet in thickness. The total
.thicknoss ot volcanics' is probably much more than 1,000 foot,.but
owing to the faulting and ,til,tine;, reliable ostima:tos arc not possible'
without moro detailed study.
. ' No wells or springs wore reported in those volcanic rocks.
Several perennial natural tanks 1'101'0 observod in tho mountains.
y
Wilson, E. D., Goologyand minoral doposits of southorn YUma County~
Ariz.: .Ariz.Bur~ XvI1nos, Gool. Ser. Ho. '1, Bull. 134, p. 185, 1933~. 1 • ,
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Q.uaj;~.FE.E-!..Y-1Jj_b.asal ts ,
In the Castle Dome Mountains the older volcanic rocks are capped
by a,series of basalt flows of, probable Quaternary age. SignalButte
is~omposed of a dark basalt that is younger than the Cretaceous (?)
5
and Tertiary ,volcanic tuffs" breccia,' and agglomerate of' the Castle Dome
and1fu.ggins Mountains. This basalt, is tentatively regarded as
Q,uaternary in age. .
\, :\ The.basaltic lavas are essentially non water-bearing in the area
'because of their lirni ted extent and the ir high elevation.
Sedimentary rocks.
Pr€~,:-:Te_rt i~~y-LfuOCks
. In a high17ay cut on the east 'side of Telegraph )?ass, in the Gila
'Mountains,is an exposure of boulder conglomerat'3' about 800 feet above
the Gila River. '1he conglomerate consists of gneiSS, schist, and
graniteb~ulders in amatrix of coarse red arkose. 'Ihe ,boulders are
suo-angular to poorly rounded and some arc as large as seveJ;"ul feet
in diameter. The conglomerate is non-stratified and rests upon an
uneven surf'ace of granitic gneiss. The stratigra,hic position and
lithologio'character of the conglomerate indicate an age older than
Tertiary. E.videnco is insufficient, however, to ass,ign a definite
age to this formation. ' ,
In the Lagunannd 1'luggins Mountains conglomerate s, which may bo
of'Meso,zoic age, arc overlain by Cretaceous{?} and Tertiary
volcanic rpcks. Vlilsoz8!, \'lith reference' to thoso conglolueratos,
states: (
"Tliose strata are gray, brovm and maroon in, color,
and seem 1i thologically identical \7i th the Mesozoic
bods that appear twelvo milos farthor north in the
Castlo Dome Mountains,'''
These conglomoratos al'e 8P tightly cGnlcnted that they arc
essentially 'non Viatol'-oearing in, tho area •
. ~F.tJ_~_l1L~oili
, Probably the 'oldest of the sodimentary rocks ,in the basin
tontati vely assigned to the Tertiary, aro the a~kosic sa1l01stonos
(sandstoneformod from granitic debris) exposlJd in Baker Peaks and
.Antelope Hill and in the two soo11hil1,s 2"4- milos south\7ost of
Antelope Hill. A log of a Southern Pac,Hie Railroad wall'
(899, table 2) at 'Jellton ShOVlS sandstono at a depth of 1,000 feet.
This sandstono may be ecluivalont to that of .Antelope Hill',.' On the
northmHJt cor11orof the Gila Mountains and the extreme northern cnd .
of, the Mohavlk Mountains aro exposuros of similar arkosiC sandstone,
thin-bedded gray to rod shale, and cobbla to boulder conglomorate
with' an arkosic ·matrix. ·lm outcrop of similar sediments uns observed ,
~ on tho m;.st side of State lliglmay 95, about 4 miles v:cpt of' Domo.
Til ted, well-.stratified, weakly-consolidated, cross-bedded,­conglomerate,
sal1dst'one, arkose, clay, and silt are exposed at the
northorn and of tho Gila Mountains, and on tho south sides of tho
Laguna and Muggins mountains. These rOC1(8 are probably of Tertiary
age. ...
fI
Wilson, E. D., OPt oit., p. 219.
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. Between' the Copper Mountains and Baker Peaks 'is' a range of low
hills,that risetoa maximum height of 4pO feet above the plain.
These hills are composed of non-stratified, moderately· cemented boulder '.
conglomerates. Similar conglomerates were. observed along the northeast
,side of the Gila .Mountains and at tho northern end of the Mohawk '
Mountains. '. .' ,
The elder Tertiary (?) sediments in the'area ~e generally noer
water-bearers, as they are'usually1tightly cemented. The loosely.­cemented
conglomerates exposed along the northeast side of tho Gila
Mountains may take in some vIator. Soveral vlolls' in the area penetrate
the,Tertiary (?) sandstones, but 110ne of the wells are known to produce
water from this formation. No springs were observed or reported that
derive wator from the oldor TertiarysedlmGnts. Tno only perennial
natural tanks observed or reported in the Tertiary (?) sediments are
khown as the Bakor Tanles ,.011 tho south\7est side of tho Baker Peaks.
Those aro natural.potholes in the steeply-dipping arkosic sandstonos
and conglomerates. , .
AllUVial fill of' probablc'l'ertiary age a.'ldthoolder Tortiary
sedimimts constitute the major part of the material thatoccupios tho
troughs beti10en tho mountain ranges of the aroa., ~['he Tertiary alluvial
fill is. not exposed at tho surfaco, ,as it is covered flith QUaternary
alluvium. "i[011 logs sho\! that tho Tertiary fill is composed mostly of'
clays, with minor amounts of silts,' sands, .and gravels. The contnct
between tho Tortiary and Q.uatornal"'J tormationsis uncertain; oWj.ng to
thoir li tl101ogic similarity. Therefore, tho water-bearing charaotor-'
istics ,of tho Tertiary alluvium are discussod in tho i'ollqwing section.
gp~ ternaFL~~~d T~..rt t8:PL_allll.:Yj.J!E.
Alluvium of Quatel'nary and 'l'ol'tiary aGe underlies the deoert plain.
between tho mountains of the ~,7ellton-{:ohank area. The Gila River and
its tributary uashes have tormed torraces on this alluvial plain.
There are thro~ pronouncod terracos on the north sida 'Of tho rivor,
the lorrost of which (~~flrst torrace") is tho floodplain of the river .•
Tho third or oldest (highost) torraco was not obsorvoo on tho south
side ·of tho river. '1110 matorials tmdorlying tho socond and third
torracos rlill be discussed horo as noldor allUVial filll'., and those ..
Undorlying the first terrace as "younger alluvial fill".
Older alluvial fHl.-Tne second and third terraces on the north
side o:r-the GHaRi vel' lio adjacent to the lIhggins and Castle Dome .
mountains. At the surfacaof the third or uPl")cr torrace is a ·thin
mantle of boulder conglomerato that ovorlios Undifferentiated,
Q.uaternary and Tertiary sediments. This conglomerate is composed of
poorly-sorted and loosoly-cemented boulders of gro.ni to, gneiss, and
schist and at rhYOlite, basalt.; and other volcanic material.' Tho .
boulders are angular to sub-angular. At the surface of the second
terrace is 5 to 10 feot of cobble to bOUlder conglomerate. , TIlis
'conglomerato is undorlain by clays, silts, sands, a.nd gravols of
undifferentiated Quatornary and Tertiary ago.
", I·"
' .. ' \Thei;y~ungeraiiuvlal.fill is'composed largeiy,of gravel ;~hd<~and
:wi'th"'v~rYl~ ttle ,silt ~d clay;andiit yields\7aterto vie lIs more readily
">thanthe: 'o1..<:1er. alluvial "fill~', . Availablo.vlelrlogsshou' al t~rnating beds l .'
: ot.gravel, . sand, andsilt\\7ith stotallna.-X:imumthickness,of about, 100'· '" recto . 'B~low :tno.youngeralluvial fill·thelessi·porme'able rlater'ial of" ." .•
,:the,;0~der,fill'.·iseucount·ored .. A1th6ughthe ··yoUn¢Orifill 'is.conlparatively'
,thin,<the'prop'o:rtion .ofpermeable· sand and gravol \is~o largo'tllat. it is '
possiblc,to'obta:l.n a 'largo,Ql.lant'ity'oi'wator .wi thaSInalldra\ldm7n~, ",
They-ields: ot •. wells rangetrpmabQut60()t04,OOO:gallons'amiiiutc, wi t11 ;.
drawd0\7rls.of il0to·20 teGt • ThcslJccitic . capacitiosofthe ~J(Jlls :rango '.
fromabout 60\'toabout~OO,galloni:(aminute :nerid'obt',or, d1'ai1dotill., "l!ll
irrigationviatcr,in: t:hoarea . is'dGri vcd l fr6m~ 17011s iil' thcse:materials. , ' , ' , ',.' . '., . -\,
, " , '
",' :' ',"; >;', ':, ' ," \'" ,'. I"~ ~'\" : • \
:. I' 'I ',.' .. ' '"Rochargc .
'j )1 ", \ .,.,", :,.", ,,,-,_,_" ! '"."",,' : 1..,,' \,- ! I ,Rochargo of the alluvial fill oi)tho aroa is; from. four,sour.cos:, .
('l')' Infilti'~tionfroni' 1'lowsin the Gga Hi ve:randit~;tributarY/i7ashos:
'.(2 )"infiltrat ionfromiirri'gation,water .applie(J>iothelana.;?/· ,/ ....
(~)iunderflow(iof/the Gila Riv;er into the area;,:·~l.lld' (4) ;rainfall. .
: /,//' i' :,' ' '" 'I .• ~' " ! ". ',:" ':' :" \ "" " ,', \.) ~.< ' ", ' . , , .. )
1 • \' ',', " ""."" ~. • , ' ,
, I .• ~I~iiitJ:.a:ti6~ from "st~kamSfi~:~i~~~~e :>ot th(/ principal sources'
, " "',', (I .,,' .', 'j,," j c. '".' ... , :..., 't :.' , ,_',',"'" . rechargeto.'the'ground-naterroservoir 'of the Viell ton-Mohawk area.
, Most'\of' ·~he. rur?,ffin"the. ~m~11G~;VI8:SheQ~md .~reek?/ .di~app~ars".1:ly" .. '/., {
::se~:t:>agei~n to '. the' s:tream; bodmat~l:'.lals ,and/the .\7a ~er c,lthor:.:porcolate s, ...... .
(totheu~te~tableor ',. r~turns to Ithe.~ir bY,eva,por:ati~n and>~ran s:pira, :tion. ,.
,.NOi;t?sts(Yl~:r(r ma~e'in~hisl a~eaont~orate \Qi'., ~nf'iJ.t:atio!l fro~ ~lows ... ,
in desert v~ashes~' 'The. 'I70rkof Babcockand:Ctishlng.11 1 1nthe/Queen Crook
.i,·, area: sl1o\7sthat ;'in. that area, /aboutono-half of the rt otal' stre~Ull florT .
I , I,', , !: i , , ",,' " \ , ,It • , ' ,," ", '\:, ,", " ,,' ~ .. ' , " , ; " \.. ~ \ '. '~ ''''',' <,' " ", I ' , " ' " ..., <'is recharged to. !the'ground-nater. reserv.oir. In theii7ellton~Moharlk.area,
'".-:: ,I". i'.'", \' " ,'", / "" , ", " . ,j, :", " !' ,f,' " " ! .' ,,(' ','; '/' ' , ....•. surf~ce florls,in.the,tributary 1:;~shesseldom·reachthe Gilo.,Ri vcr.. . ....
. :A.t. ihfrequentintorv~ls~ . surface flor:o'cciul's'ci~lthe Gil~Ri vor'and','
. \)vlate~percolate s,dm7n through ,tho coarsc/ sand~" andgravels'\ of'· the:.r'i yer
ichannel itO" the',vlate.rtable'; .. , "\ '!' '"
, , , ," ' ,'. ' .' ,'",' ~. .
. ' .......... ' . " Irrigation 'i \'.i·, .... ..'\ .. ' .' .. ,. I' .,.. .. ',., . .... , '. , . '.' . . 'ilie .. recharge . from irrigat ion { seepa8e . to'theground:"w!lter 1'e ser.voir,"
ofitheWellt'on-Moha\vk area'. 'vms' estiinated:to' .oo,about 9,060 acre;..,feet:a
'iye~rin19447"45.;:,IIhis' valuo\vasbasedontosts made in the Safford .
'; Vall ey ,"\1he1'o' somewhat'sim11ar' co ndit fons . exi sit .~.· .. !i •. In. t he$~ff ore! Valley •....
:'.It;.~TaS:dot~rm. i. nOd .•. .t. ha.ta.b out. 25,per?cnt, o~ltho\rm. te~ a.p;91ieddirectlY .to
'the land ,uas r,echarged to;.the \7atertablo!?t.. "', ,i, ." ' .. '
. '
, '.. . 'Un~cr1'l~W', { ..
.... Undol:'flovr.Jofthc·G·ila·.·River\throughAthc·alluvialfill'contributes
!recharge.to i.h~. ground-waterro~6l-vqirof.thearea ~ . Tho underflm.71 into
"the ar?sa tMo~awk 'Irnlsosti~tod tbbe5; 000 aero-feet a yoar: %f~
.: estim8rte,is;only:approximato, • aiid'lictailcd \studies \-rouldbc roquii';c.d
,',' (', " I·, ,', ," ,"\ ,',.' ''',' ""J,j \' '''obtain a·mord· QlCact :figUl1 C. . )
'~~I'il ••.•.•....•...•.. ' .• ' ~i{tib89cik~I,.~l:~fl;:~~d\d~~1i:ilgl .·~.L IJ1'( R~~ti~1~8~:,rcr ~~~~tl&tt~atcl~.'i~~~,\. i .'
" i'lbods'\ih)a typicaldos.ert .rhlilh', il.1ihal County, Ariz.: •. ,..Amf Geophys •.
" ", " ! \ "', C' I' ,',J ,} " \',,1 \'" '. < I, "" ' '. ,'. ';, ."i ." ", .,', i ,1'\, ~,! ., .'..,UnionT.rans.jp,:52't:194L '.: ,: '.' •...... , '.' .1" ".
·.El";." .. " ' . '.'Ii. .} .' ;, • ',/: "'/:.; ."'." ...•............ '. /
'Ttirhcir; S~ :F.; and othors~ Vlator ·ros~11rc·o~,of(.S~rfo;d~nci Dinc~n~\ ..
" virdoriVafi6ys,',' ., ... , , ...... '·$ur\tbY(inir.icograp~~d)(
.i p~:: 28,,)94i. ."
1 • I, <i.'\"
I.,' ..
,",I'
; .'. g.
I . '. Rainfall" .
AS th~: :c11mate is' arid, th.ere 'is little recharge directly 'from '.
trairlfallto the:ground'::water reservoir' of 'Ithe area~ .' Upon reaching the I. '
land surface the' tlater from ra'infallruns loff as surfac01:rloWOr"
percolates into the ground~ or may evaIJorate' back 'int6':;the,ai~. Most: of "
t~e: . water! that. ,~nt~,r,sthegrourid di.r~qt~y. from r ll infal;.l: retur~s. to~he
, au by evaporation and transpiratioWand does l!-0't reach t!1e Vlater, .
~able' ... ,: , :, .... ,. ., "'i' .: .. :., ,:,,' l' :"': .. '1,.,' .• :
:,'! ,',.,'
• (II',. .' /, '.' .,Move~~.n~,:'.<?f..:.,£!..~_~!"!.Uter I'" ','. I. I .
. ' .,A contour map of ,the ,water table vras prel)ared as of February 1946
i (seepl~' 1)', on the , basis of water-level':measurements:,in HeUsand'
·; .. uponland";,,surfac,e,'elevaUonstaken . from topographic maps ,6ftheBureau:
'orReclama.tion~United,States Department of the Inte:dor •. This uater"': , . .,' .''', .' " ': :. '. . '" ", .' . II " "
I table contour map helped to determine the source aIiddiroction of
. movementiof.the'ground. vlater'. . . ...... . :,' " . , .. ,.... ..'-
. "I: .• ' Thelgl~oundwater moves ,in, a, uniform manner down .tll·eslope of· the
,water tableper'pondicular to thecoritours.Tne contours . show that the
,genf.:rral.slope'qfthe water tableistorlard tho Gila Hi vorand t()the I,'
west. ,The l7estward, slope of the "Jater: table decreases from 10 feet per
niilehear the 'northern end of the Ivrohai'lkHountains to 1.3 feet·IDor mile
nea:r'. Viellton •. Thlsdecrease in slope .. is, largely .caused 'by heavy pumping,
for 1rriga-tionalcmg' the Gila,Riv~r ,inthe vicinity of Roll, and,Vlellton.
'Ihelowering/ofth~.watertabie' in the 'irrigatedareas,has, increased'
the. rate ot movelTlent of groundwater' from the outlying areas of ol~ef.'
alluvial, fill ,tm7ard ,the Gila' River.!fuis movement is esr.ecially .,'
. noticeable. in the vicinity oi;7ellton, ';7here the movement~ of, vrater is .; i
'toward'thEipumping 'area from both sides of (the river. .
,. -, (I.'·;
';. ;\ '. 'I' >':\ :' ,', \ " '~ .\
'.' .' ! " 'pi scliarge .. '.
Ground water .is dischargod trom :the.basin by pumping for irr~gati(m
~nd:bynatural:me~ns.Naturaldi~chargeincludes transpi~atioll and
eva.poration of ground wator/i.n the area.s of dense groriths .01': natural
; vegetation along the river channel, 'and,underflovr'out! of'thG8.l'ea a16ng,
- ,the. river. chalmel.through the, narr9rl~near Donie. ' There is 110 . nat~ro.l
dischargo, or'grcnind rrator 'bY-surface flo'17 out of tho 'area.
. ,. . '. ," .:, . I . '. . .' , I. " .,' : ,',
'. . . \'. .' "PuTilpage ' , ,
All irrigationwatar'intho are8, is obtained from:llells;rI'ho i
ir~ig~tion TIcll~ ~a~lge in ',discharge ',. from. ,600 t()4, (lOO( gal1?ns a minute.
Jlost ,of the vJells are drilled to a depth'of about 100 feet •. ' The .
a:\r~rage pumping,i1ft. is from:35'to 40 feet. . . -.".', '. "', .
I, The tuUount 'ofrmter pumped ,from \7olls in the area for. irrigation
was'comIlUtedto be 37 ,000'acre-feetin1944 .and 35',000ucre~fee:t in 1945 •. 'No. pu.mpingdata arc available for the ye'ars prior' ,to 1944; but the'large
\ ." .". '.. ., ~ , .'. ,', .. '. 'r.·, .. ". " "~.\ , \ ' '.' I number'o'f.abandonod.TIolls and farms indicate that pumping in, the past' .
,was greater thanj,t\is at"present. 'A record.of o'achirrigationrlell'
was made, andthc quantity ;of. \7ater' pum:oedbY, OaOh\7'011 rias determined,' i
'for-the years 1944~45.' The amount, of VIator pumped u.as'deterinined as .~.
fo1lom3: ; 111edischa'rge of the rIO 11 i,ias measured either rrith acurr'ent '\
meter6r;~a sharp-cro~ted i1eir, or by the' trajectory method. \"IherO . . .. , , , .. 'y'--, -. ...,......- ':'
, .. .~, i. ..' Turner,' S.'F.,
.basin, Ariz.:
and· others; Ground,,;~.ater resources ,of tho Santa Cruz
U ~,J S •. C,-ool: Survey.(mimoog:raphcd), pp. ~3-61, 1943"
\
,"',
.," "". ,'I, '",', ' ,'.' ""
«,el'eetricp,ower'Uasiused,/the kilowstt.;.hour, demand. for" each purflpwas'
,measured"a~d' the;:numb'er" ot hours of ' operation: ,wascolnputedfrom., the ,,'
,po~~~~ec ?rd, ~',11t~ Moh~wik 'fAmle ip~l~' 1Jliter ,Consertrit ron' D1 str,ict' kep,~L,
',a,ecura~ere.eo~d$ of the ,numberot,;houi\s eaChof.~heir : pumps, was operated,
(.~hi eh, gre~ tly,ta.Cil,i t~ t~d,thy\ P~lllpago, ;;comput,at i?ns ~ "For:,the'f'ei1: 'itO Us'::
"Lllhe:r~diesel>an~gas91ine 'engil?-eSllore .:usod', tho amount ',of \1ater:pump~d
,'ilaB,estimated.'""'",, (", '., ,i' ' .. 1", ' ',',. " ' '
, ,·',I~: is"esUmate,~ \~ha~a~out75 per§eritof,th~' Sfaterpumped~isr'
discharged :f~om the, irrigated area through transpiration'and' evaooration. ' , .' \', " ' ,'",.".' \ ,. Ii," I) ,'.\' '<, ' .' " ' " I " ' ", ,I'" ,,'''' " " ' ,Thisamountod to alossiof17~ter fr0In thoareaof',about' 28, 000 acro:"f'ect
in'l~~~\an~ '2~,ooq~C(~:f~eot:in 119~5l ( < ,l,,:" " ' ",1/"-'
,,\i':.i;_' ' "'" ',. ,"', 'NatJral,diseh~rgo,!' " "" '.' ',' '/. ,. ,." .,', , ''!( ',',' i:! lJlor,~? ,~he ~9'V0lo~ent, ?f,irriga.tionwell~J.,natur~l:dischB:rge,fro~
the~ aroaoceurred\at' thelorrcr, end as both surfaecflouand undorf1017 of "
~he /GHaRi.:ve:l,and; ,.in' aMitionr disch'argc.occurrod(thr~ugh,ovaporation '
0:4dt~ro~gh' \~ranSPira'bion;by'phroatoPhytcs'(ilator~16ving' vegetation) ':
,;,groning: along ,the rfver,bot'tom. " The lowering of ,thef.natcritable t11rough,
!\Ii,\,:'pumpinghasi greatly rcducod~ the un~crfl0\11oaving. tho'varley. ,'TI{o ,:: ,\,",
"lo~lering ofthe,uate'r,table:a1so,hasresuitod( iD.(asaviUg ofrrater' , '
ii, be~ause.the\natul'alvogetationhasbocome. loss i abundant, so that ,'thoi,
'anlOunt ,of,natcr' transp'iredis sma11er~ 1b.oi' amouIlt' ()f\lat,or' 'lostbyi '
" ,.' '~ ,,' " ",' \ , , ',! " ", "\.' ,I I,'. ,.' ,'. _ ", ). ",' "", ' "d1rect"evaporat~on,whore tho ,;uater tablelsnear ''bho surface has also. \
(. beenreduc?d.\No data ,:.lere irvailablcto,compute' tho amount ,of 'uater ,i/~
'.fost,'fromtho'·ahla ,through·,eva:poration'a~dtra.nspir~tion:'irith~' river',.','
\ ' :,-, 'I,' '\ 'J ',,," ',' '_.,'." .\' / r, , -', " ., 'I, ,/,' _, ':, /..' ' '," :" :t, - " ':
',bOttoms~:,Horlever;'it can be' assumodtliatthis'itould',amount,to, several"'"
1 l' ". {'\,,, ,- , ' / ".,: 'l, j ! . ' . ~ ,,', .,', ' r' " ~' ., '\' " ,i " . " ,".' " I. .' ~ • !, ' [ , " ., " . " , ' '( ,
I,' ".~.110u.~and:.a.". .c . r?:.f.....O .. ot. '.i.e.. ~Ch,Y.o.ar.'~ ..... ~. ~.·.s ... ass.u m... ~ t.l.·on.;is.ba..s. ed. '.~.p.on.\,.cxp. or. .l ·ID.en., ts., conducted .. in',theSaf.ford ,Valleyll"uhero .~t· \;as. computodthat. 12,400,', .'
a~rosofdonse river~bottom vegotitlon,iusod 70, 000 'aero-feet' of .Ilat~~ .' ,.'
,.ti.nnua:lly ~y' '. \\, !'.' . ... .
.. ,:;, 'Ul1dorfl'oviout, of, alluv1.alfH1"
to\bti ll'.l:sd;'thanl, 000 a year.:'
.' ! ,,, \
, ," ",' ,: ':,,\ I ,,' "', ". ' !~', ":1 1\" j': ";'" /:"'.: ',I ,', 'J '
'. ..,' ; Fluctuation .of· tho( water··table' . .', <i .... •
1</%'0 'tw9 principal facfor·s~'that affact~tho: lovolof:the~' gr,6und-wator .
, :reservoir :aro .thepumping ofwatcl' 'for irrlgation and thc,uSO .. of.\~;rator··
by uhroato:phytes~ !, :A. :s~udy.()ftho.wator~lovQlfluctuat ions'"shol78. 'that, .
, ",~, ' ,'", " '" ":,' . '" " . " ":, ' \ ' ,: ~ " '.' ,," I I ,:,"' ,\.\ ,", ~ "in tho al1uviaLfi11a1ong:theriverbottom,thorc. is a seasonal"
" " ' " ",'" .. I I \ '. ,; , ":' ,!" e' , ' ,i .' ' '.f, ' I 1"1 . ' , \,' ':.," ,', ",' ):<, • ,; " , " ; ; " c' ,.-, " .' ~. loworing !of.· thcwato:r: table during tho pumping 'soason,\7i th only: a' .
-,'<',-! ,," ,", :,.·,,',,',1', " ~"" '.< 1',,.' ,) "':: '~'.: :."1} "'\ ... :~''; I'> ,:,' 'J ' • '; par~la~ recovery af,tcr;:.tho. PUl11Plng. s(}a~on. , .':. .... . ".' '! <.'
. . 'There has:beena gradualdowmiard trend .. ot.: theu'ater.table in the
~rea: since heavYPUmI)j.ng'st?rted( see fig .(2). On the '; basi's of ", "
"information obtained from records of the 'Mohawk Munici:pal VTater
'Co~~ecrya:ti(m Di~tric~ . ~d: from the 'l~pal :rarm~rs ' .. the\ wate'I'~able .' .'
ta~medar~ashas been:doclining, at .an.average:rate ,of .. 0;9 foot ,a ye~r
,fo~'the:,past 20 years ..Water levcl'sin Ilellso'ut,side ,tho'farmed area.:,
!.~11ayG.'noti ~oclined,a~raPidlta~::in t~efarmed'ar~a,: I~le(:~mo~t: ofwator
.\"lwfthd,rawnf,r?m,steJi'agc\, .~~l:ndlcatod;bythe d~ellrl:l,ngVla~er levoS~'
estimatodJ,to\havo averagod about 14,000 acre:-:foet'a.yoar. .
,'., ,,:,"':.', '<, 'I': '" , ' \ I ,,' '.,
,--- Ii",
'~ ,
'" ....... ' .., .. .., '. Irrigat'1on ....... " .'
,:: ~ '" j <,,' \' y! • ',' " '" ;,'\ ' " '.. ~ .' '.. . Gr6undwaterstrom .tho youngel~ alluvial fill are ror the mos.t part·
"ixlJurious>.td.Unsatisf<.>.Cto17"' for dirr'i.f/ation,'according ·to'.the .'(' .
classification'·ofVilcoxand :1kgist~ClF.?I •. not >.one 'Of·.·. the'~e v7aicifs l is~' ,
" ,', ,'l', 'I' "-,i" '..' 1 . \ ", ' I' 'l' " : I. ,1 I' I ., . , ." low enoughih, dissolved solids, 'andsOdium' nercentageto. be 'cOnsidered" '> l' , ,1' \, I)' e',' \, ,It " , ,I , ... , I ,. ." 'F' I '
}~excellen't.to gOOd~1 ;'andproba.bly"nonc . is low enough: ill' all constituents
. loyen' to be consider,ed. "good to 'i,njurious'! .Agri~ultural,devolo:prperit.of;i
'"\·:thearea. has:.been retarded by the poor quality of the available. water •.
, .... '.' Many<:.wells'.in the, youriger fill. now. y:i.eld, V7a,termUchmore.highly .'.
'( ",' \, I', ,'I, \', '<, \ ",- 1 / "'!' ,r" " < " minera.lized than they yielded 10 or even 5 :years ago.,Thedowmmrd',
tr(}nd.'of ;\viiter levels in.'. theiaroa has': boon accompan1edbY all/upward;'
. 'trend ''in\ tlle .dissol ved~solids.\content of. the water. '.Figure:,2, iiiustrates;.
th'e\se'tt~nds ,for' viells 689i f:illd '812. ,:7011 689'had the. most highly',' ....• ' '. .
, C h ( , ,. 'I', ,',' ,\ I',"' • " 'i, ' ., l' \ . 'I" , '" ,'.' \, minoralized''I;later of ' the 'area in 1946.' ''1''111s ,"later has increasod about.·,
. ,10:>timosiu clissolvE3d-solfdS concentration :sinco 1927.~ 'The' water"from·
, ,'78i1 .. 812 has more than :doubled.in dissol voc1:-so1ids . c'oncontration.s.inc.o,' ,\ \' 'j' " ,,' , \ ' , " '\1'" , 1925,' and 'most . of ,the chango has occurred since 1933-. .
, ' ,I' :r: . \ "< 0' ': ,,,'.' ",,' \'.' '. ,~,; f". " , r)' ,
_i---""--
, !;:' ,'" '" ,'I"~ ("I I" " J', 1/ I' , ifldischarged from the ,basin by .plunpingfoi- ' .. , ."
\,.irrigation 'and: by natural. means. Natural' discharge. includes' transpiration.
", ,,', " "',' j .,', '\' ,\'..', ~ " '" ~ " "'" \ \ I" • " /.), , " "I .. ' and,evaporation.ofground water·.m·.the .. areas.of dense'.growthsofnatural
" ~vEigetation.·aiong.the\ riverchannel;>an'dUnd~rfio\'I: ollt:oftthE(area. along'
...... \.tl:~/r'i.ve~:channe~\throu·~hth,~lnar~Oi7I3. nea~·>~oIl';e';(Tl1e~e 'i~,~o '1l(atu:sal' ... ,
.:: :dlscharge . of gro:und.\1ater by surfaceflot7 out: of. ,the .. area. : 'ilie amount \
" :6f "water,I)unlpedfi'om 'wells in ,the .\ar~a,was \conlpUted,'to.be37,000 acre:....
'feet'in1944 aIld35, 000 acre:::feot.in '1945.: \'ioout ,tb.ree:..fourths oi'.thci' .' ..
-. ii" ( "'", I ')'" I:.' " '. I "I ,t.,' • \'., I" t "" ... 1 :",' \;, • /. ','. . ; 1'" " water pumpcd'\1aS discharged. from theirrigatedarea . through{transpiration·,
" '",' , ",; 1/ 1 ,,' • -{ , I ,I' 1,\" \ (. ) I ')\ ". f . and evaporation. This.a.ro.ounts to (a loss oi'nater from tho area of: about,' .
" ,<', " " '" \ \ l" " ' I " \1 ' ~ '/,' I,' '.' , " • 27,;000 .acro~feot'ayear •. UndorflQ'(V' out. of tho' area, . through ,the: alluvlal
fili, wasestimatodlto'be, le~stha~i',OOo ~cre''':fcet a year .. <.:,' '. ' ;,< , ", \: ' ',,' ":,\' ('",,,' ,'I" '!,' , , " " ;'"l \":",J, ( \ \ .' •• Th.e watertabloin' tho farmod,areas has. bcendoclining~ at: an'averagc
~ 'j.. "" ", ' \ " ,'f " ", ;" • f " " / \,' '"' r " I, J ", ,,' ,I , , ' , " ' , ' '. rat~.of.0.9. foot. a yoa~for tho ':!,)ast.20 ,yoars~ .. ~7aterlevGls invlolls,'
outside:;tho farmed :ar6as' have. not doc lined as rapidly., .. , ". 'J/ " l ' '. '" ,. >, ' ..... ,' ,'", ,'., , ,I . ; .. <Th.e'ground waterdn:theyounger.'alluviaJ:'fill of the area is
1\ ,," , " f 'I, ' • , \, '" \' ~, ' , ' J,' i (/, " \ \ I .' "
j mineralizcdiand'most:Of. it ,fs "injUrious, to, unsatisfactory":for .. , ,
.·:.irrigation. . On.o. well' intlio area yiei'cledtwater containiilg ,2'2.4 t'o~s \of;:"
disaol ved rilatter 'iPer acre-'foot.'Generally,:wells in tlteH older,alluvial .'
,'fil1'yieldwat'er:.that'is/less· highly' mineralized' than water from the ..... "
'·youngerdill.,,'Iholnos't highly' mirieralized' ground w~ters occur in the· )
irrigated ;·d:istrict.' .. Bo6auso onlY,a' small amount; or" dissoi vod" sal'~s can
'," , ", ,I" 1") r",\' "1\ ' , ,. I L \" 'J,' ,. ,',' , / leave. the basin'; ·the 'concentration' of dissol ved.m.atter, in ground waters/
) , \ ';,' I' ','., : '" ,',,' J " ' \ J \" \/ • \ ,,- o1'.the' area is 'increasing. In. one \7011, for .example ,; .the dissolved, : .
mineral:· dontont hasiil'cre~scd' IlO'lt 1IDes';sirico 1927: I,':'! ,I, \ .. '. .'
,.' . .Although:.acomploto . inventory 'ofthegrolL~d \v~tor'in'tho: are~ has,
not'mad.e;· itis'evidel'l.tthat :thc:m~ount 'ofVJat~rannuailydischarged is
,I" Ii. " " \ ,,' .' I "I ", "," ,"'! " i " ,.' 1 Imuch;,greater than theamount·of, water anmially'rocharged~ . 'l:ne' excessive •.....
, loweringbf,the ;nater table and .. the' ii:ibreasing chomical.cQ}"icontrat ionS!
.. the·wa:ter'shovlthatthe ,safe annual yield'has, been gl~GatlY exceeded, .'.
, ,,' , ' , J ' " ,\ , ~ .' . ' ',I • I , . ~ '< ' f \ " '/ I.,." ~ \ \ both:fromn.quantitativeand fromaqualita;tivo stand:!,)oint.' .Aboutil.·,·
',"\ "I., t" " \,', ) \,' \ ',\ l,.· ",' " . , , " ""', ',', ,'I 14,QOO.a,Crc:",foot'mort;l water is withdrawn oachyear.;rrom .tho grolmd-:-:water
reser.vOir·"than is recharged.,,·.' , \ ,.. ' ' ..... , .. '. ,'.. " ..' ,,, ',\.,1 i' ." , ,.' I I' I), \ f, " ," ;
·.::.',Th~'.lo:lering.of the~v{ate:l:'t'1bl~ and!tho. increasing salt!. .
concentration of the 'ground water,poillt.,to·a continucddoclino, of·'
, , " ' , " ' \ I >'" i ~"j , \ ' , ': I'. \ ".' I I I',) " ':.1 ' .\ , <. • I '.,< • . agriculture .in ,the area .'Thore is 110 way of .' lm:proving these cond~ hons.
I,exccpt', by/tho addition 6t .. water: of 10\T<chCfu:Lca'l concolltration: If .'!' .•.....
,'addi ti'0llal v(~ter,icould be: a'dded'\:Pr6vJs~6nshouid\ ~~mado.~o:·i]ls\iro ,that ..
' .. enoughi, water loaves 'tho .. aroa'to. removo.tho excess', sal ts,. 'A program of '.
':p~rio~ic"Fcitc:r~'le~clm?~~urern~n ts' \al:d~1~tor/ana~y.s,9s Sh~~~d"b~ ..... , .1: ". ..;
.· .. undertaken in'this event, to detormmo changes 111 olevatlon, of the water
\,' .t'able~/changes'irl'tlio ,'cOllcentrat ion a! dis~ol vad'/minoral Diattcrinthe .
. "ground .nator;: and the .. amount 'of 'salts, cnt~ring and', leaving thoaroD.'.:: .'
'. i',''':,';''',;,,:, ':":)":'1',:/1,";:' ,:",l':" ',' .... "..1' .'/ ...... " •
Records of . typical wells, Weli ton:::~i()ha.wka~ea I "Yuma c~urity, Ari'zona-Co~t.
\ '-," .. ,,'; ....... ': :':' r' .:: ,;, ;;.:.,:.:.".,: ".;,~ I.:;, .... ;'; ,. . ;,';:, .. ,I .y ,.,' ,.. ,'. ... ,! '." .!" '\' :." ,;.,' ';;," :i':':' ::, ... :. ...... ,~:...,: ,;:;" .. ',''''1'' .. '" :: .... ,: ':",'" f":' ,,: ".:~ ~:"!. ";':" (:,.:.:, :,;,:::,,, .. ,, .. 'I; •. :.J .. :"" .,. ,
'.;. inTillar,' !\'Da.tel~ti;iUd~"DElpthDiam~,
,i .. L. :com-labove , L ··of eter
:1" 'plei lsea 'level well .. )l of ;
:~ j:ted::t(fe'et)1 ,(feet)L well.
:'~:':·rT:'~-~;,:~::·~~;;!:·~-·,::;',,'::I;;:.-;;~~d'·:f·'I~"j:(~~:):·
t .S'-tiNWi- sec~\5 .. ~J;eo·,liughes;' i~ecker. ,f 1945j,·,. . ,1-'95 \.3 .
. :.':~':"'" "'1';";"'" .":;, .... ". ··\'·,'''';:·;'::::·'·'·;;:'''r·so,j:th·~'~r/:·:·:, .. i:.~,,)"""";:":\""".:";,;, .. ::,;,,.;,!.;,.:.;,,,, .. ;,:;.,:.'\ ... : ... , ... i.:,: ....... :+ ..... ;.,:,;:.: .. ::::\".I:': ........ ::.;:." ... '
", .. ~.9/~·: t···~·:,~~·g,~·,··5.,· ~ .... "',j,:~~~~.f,~',~,,"~.~ .. ,~,~.I:.s. . ;~ ..' :. .. ,,:::::. ............... !,.:.,,:.~~9..~l.. ...... ??~ ... ".. . \. .. ~:,~.f,~~. ... ~,L .. } ..? , .... ,,: .............. ,\
, , d \ ii' . ". i" I • i el t· and j.', " ii, \ '\ I . '
, '~16! SE1-NE'; sec', .9 ' , \,J.'W.' :Selt jMiller .! 19271 397 \ ·290 1',16
.... ~,··.·.·,:·~.~ •• ~·s: .•.• m~:l~··';;··I;J· •) • ·'·,:'···:1"·.·.·• •. :,·)···\;, •• ·:1····· .. ·· ·it·'.·. • ·.·, :.:1' ······. •· .• · 1-·:····· '. ..
\:.9.621\NW:t~ sec .. 1 ,[<Rohrbough,; '." ~, .' . '. '.' J:, ~., [220 .. [. liS ,1, 24' .J,
·;~;~~l5.. . j"l~~t .. ~~~.~.".~. . ".:)" .. L~,~.".~~~.7.~~. ....... "J. .' ~ ...... ,.~" ... ".: ..... ,.. :"" .. .L ... :J.~,~~J ... :.~.,::', .... ,.. .. L.. " .. . ' ~~. '.. ,: ... "~'~"'"
;9161~",l. set: 9 "I, ·ido ,'..! . ~'\' i \ l'iq'39~i 208 "",;., \110 : IB ",. F··.·!··i~:.~~• . J:.i: i.~:;.i~';;j'·:. '···'.·······'······'·t·i .....: .. ........ ". .... ;.! ........ .:.., .• j.: .• ,.:. .... ,\ ... :.•. :,:.",.: ., .';)."""' ......... .
'i :~1()9l·SWiSFi·.sec~ g !U~now~' > ',,,,,.: I· - L 177/' - .
- , !.., ~ , . , . , ,'.' : ~, . , , '.' ': , '. ", : " ': ' " ...•' •••.J ,:".' .•..,... : , ... , " ..' '." : ..' .' '.' , , , .. ,.' . , • " .. '" " .... }i~: \ "~,;.~~:,:,,. '\~,\ ~ J~' .... ; •• ",;:,~'" .:~ ::~'j~:':~" .. '~":: .'''1.':'.'~'''' ,.:~~\.~.'.\~.I •• oj "',:'::~~~' ',' .',:;': ~.~~,' ~.; ::\:,.,\: • .' • .;..':;' :,.,.( ... ; ','~' ··":·'·:.I~~··'·:'" ,.,I".: ..... ~' ": :,'~~.' '. ; .... ~:; .. ; ';' : ... , ..... ,.;";:, '. f'" ., • .... '~I Mea~~~ngpo\i~t.:~asueu:.all~l,:to~,o.feasing~top qf ,~ump base~,t?p 0F,',wat)er ?i:p~
):.~iclamp.( 'ortQP ,ef '~.,.el1eurb~ ,,:; .. ,_, , ... . '.
g; .. 'E./-, '1" turbine; OJ <cylinder; Cf', . .'eentrifugal; EI',ele~'~;ic: :G; ,gasolinei "W. windmill'. ;,c " , " ' ;, .,," 1,1, " ," . , ' ,I .' '~':, ': ' " :' \1." ", I"', "~' \ ,,'" \ '! .,; ,'". \ .,,' , ... ( " " '.. ' " \ I
<~ ,
"!,\ "
. ··20 .
. ··,90
92
• 1141,
. ;165··
.167
.167
',8
53 '
70,
77
,'+;:, 9t:;
', 10,1 '
~25;,
"130
, 1140
175/
,188
208
, 24t:;
\' ... ~
,2t:;5 ' ...
257 i
262 "
290,',
"290 '
70
80 I;,
'90 ;"
9~;
'95, !,
95 ,
-- --~ ~.--' ~ - -' . -
from typical wells' in 1>iell ton-:Mohcawk area;, Yuma
Numbers ccrrespond to:thosein'table,l --aildplate-l .
. -,> Analyses2by Geological SUrvey'.' / -(?artsper million. r
············l~r~~~· •• --·······-··········r·-··-·······-_..._ .... -.-........0:-._.- .-..............•• ~-........... ···l·
1ccnduct- -'.', Mag-:1 Sod.iUm . , .. ~, ~. ., -....
;iVel1).Date of: ·/·)ance .~'. ;~Cal-_ .~ ne- [-, ilnd .lFluc·,-j·Ni~ : Bo- ; Dis- <~Total.~:" cent.·,·
llUm- !collectioidDepth /~(Kxl05at ,) Cium~iun{lPotasSiUm 'bonate C fate. iride ~-rideltrat{r irate:) sc-lv~d ihard::::~ ,', : sO'- ,'.
her'~ '191+6- \feet)-f?/25°C.)!(C~)._ ~Mg)! :(Na,LK)l.(:HCV3) i U5()4T!(Gl) .. ~(F) f {N03}} {B(j3~ sOlidsiness ': dium
-<. ", ,- • : -- c~ , - /" ': --" J': . /- : - ~ •• • a C ~ C .
,~~~-,t~;~;·-·'··]~,~:~Ti··-rc·+···l·~;~·+·T~·.~~~T~·····+~i·IS~L2...
, 639 j Apr .. : 2 '1,010l f~190! 553!>4,~70' 475 1,960~ 8,420< - .'- / ~16~500~ S;240,-·E, .
. 726,!Feb. 6 '18.7 .. ~ "21T4:2"[372 79 .;263 L j75 Y·~3.5 ,2.87.5!l,OgOr-:--c·70 ,
790 \Mar.· 21' ~;12B '1.0]0 ·~.·684 ~ 286-[1,440' :534<>1.120 ~ 3,120L-;. . ... ...:~. 6.910L2,8S0, ( 52
.. 812 .. ) Apr ' .. : .21·! 108 .. ' . j . 865- j ':401 ! 185 ( 1-.350 r/530 .. ~868 ,!.2, 376. ).6 ), 3.i .j_.! :5. 446t 1.760 c';:( .62 • 870 ... i·;··ja!L·:3·0 ...... : .. :r·T2:'r···· .. T~· .. · .. ··73B· ...... :.·r· .... 3S·ifT2TiT .. ·· .. ·:::Cj26-.. ·_· .. F··:·26Ii:-: .... r·· .. ···4·26 .. T-2:;·266·: .. ·1r:··:r .. ··~· .. ··:r~Er· .. C'···L~t( .... 4·~·J50r::r;glm: .. :-:·T-::-····5Z .. ···
~~~1~:~{~k ~ ~§' . r:~ii '-1; 263 l1121~5~ I~~t'~:~ ·3uoll·,~~~,lt~ .. !; .2- j,-' .S{ .~2.496Lt;120~. r~49
916: Apr·.~23:290 . 339' ·.-=,l-.::>t~ . 6~.; '.~ . \ '. 725 \ -' I _/('. ..~ .,' ..
. 976- j Mar. 20. f 110· ·.1-. 411' ~ .• 112 [ '48; 722· L 294 ! .. 352 rl~020 j - i .6 ~ - ~ 2,400-L 477 i ~'77
- fIb9· .... :. . ·}.fay .... ·-.. 5.. : . ·; .. T·· .. -= .... · .. ·~··r::··· .... 286·· .. ·. ... r ........: :· .... r. . ·::··T .. ·· .. ·'::·· .... · .. T··· .. ·J\s .. ·.. ···i·:;·-.. -:· .... -~··r··~ .. ·8Eb. . ·-r:· .. ···:T'···· .. ·:::·······r·······:::·~·T··::- .. ·::: ...... ·: .. r. ... ·... ..... ·.. · -...... T--:··~ .... -·· .....
': Jo •
IIi I,
'UNITED STATES'
DEPARTMENT' OF INTERIOR
GEOLOGICAL SURVEY
1947
PLATE I. ,MAP OF WELLTON-MOHAWK AREA, YUMA COUNTY, ARIZONA
SHOWING GEOLOGY. LOCATIONS OF WELLS
USED. FOR IRRIGATION, AND. WATER LEVEL
OBSERVATION. IRRIGATED. AREAS. AND.
CONTOURS OF THE WATER TABLE AS
OF FEBRUARY' 1946.
SCALE
.~IC=-_i?===:itI __ .'.2i===::j ___ 4 MILES
@SCH
NOT NAPPED
' .. L-__ -..:. ________________ :.-_______ -.,-__ ~ ___ --_---"------- -
32' ~O' 1---1----1----
/
NOT MAPPED
g
':1;
~IOR
f '
(AREA, YUMA COUNTY, ARIZONA
INS OF WELLS
WATER LEVEL
,REAS, 'AND
.TABLE AS
=====_ .. -.j4 MILES
@SCH
Plate 1
I'
32'~0'r---~r-----~-------'+--------+-------~~----~------~~--~~~~~~--~~-------+~-----+-------+-------+~~~32'~0'
NOT MAPPEO
~~------~~--~------~----~--------~----------------~~~~~~~~---g- ----------------~12'30'
':!:
,
\
\
,0.>.
..o..n
MATERIAL
YOUNGER ALLUVIAL FILL
EXPLANATION
AGE
QUATERNARY
WATER-BEARING PROPERTiES
PRINCIPAL AQUIFER OF AREA, YIELDS WATER
FROM SAND AND GRAVEL. LAYERS,
[ITI1] BASAL T5 o ,OLDER ALLUVIAL FILL
~ SEDIMENTARY ROCKS
l~~ :~~l VOLCANIC ROCKS
b\':.':::l GRANITE; GNEISS, OR SCHIST
QUATERNARY, (',
TERTIARY", AND
PRE-TERTlAI\Y (?,
CRETACEOUS !?, AND
TERTIARY
PRE-CAMBRIAN 11,
ESSENTIALLY NON-WAfER-BEARING IN AREA.
ESSENTIALLY. NON-WATER-BEA~ING IN AREA,
ESSENTIALLY NON-WATER-BEARING IN AREA.
ESSENTIALLY NON-WATER-BEARING IN AREA.
-L..- KJIOWN FAULT, ARROW INDICATES DOWN-DROPPED SIDE
• PROBABLE FAULT
C IRRIGATION WELL '* UNUSED IRRIGATION WELL
DOMESTIC WELL
~ UNUSED DOMESTIO WELL
~ IRRIGATED AREA
" ~2~o-" ELEVATION OF CONTOUR OF WATER TABLE
GEOLOGY BY M. BROWN, G.E. HAZEN, AND C.T. SNYDER,
WELL LOCATIONS AND WATER-TABLE CONTOURS BY H.M. BABCOCK AND A.M. SOURDRY.
unl
II
UNITED STATES
OEPARTMENT OF tfTERlOR
G<OLOG>CAL ~
. 1947
PLATE 2. MAP OF WELLTON-MOHAWK AREA, YUMA. COUNTY, ARIZONA
SHOWING MINERAL COI(TENT OF GROOOO WATER.
.L.-=. .~. ·. .... t=====-....- ===~lM~
EXPLANATION
UN£S SHO'I'IH TOtAl. ilfilDW.. GOHTDrf Of
6ftOI.tND .... TER_ 1WrERYAl. IS 1000 PARTS
... ""-LON.
·-' P= ~••_ __4 r-----~.~~~..•,. - -------·"·~,-----·. .- ---~~-:------~--------~---C------------~------~----~--------------C---------_:--~C----:---------=~~_:--------_:--_:=_--=_'l
,~ -
. ./ -
South North
I.
-" ----
-;',-
Fi"g.'l-:Ideali;edsection· of valley flll;.Wellton_M?hawk: area, Y=a Coru:i.fy, Arizona" ..
.'
,
'0
. ", I - .
' .
. '" WELL 68', n MA'COUO tN. NWI 4NWV4 SEC. 3 • T.75"9 R.16W. - , 0
'\, --- I--
. ~ DEPTH 6. FE T, '00' f<TION • ELL ------ .. - - :.-- ' .
2 5000
.0 , 0000
. , , --
. f---
1---
. .'. . . -....-- ,
.. .
5000 ~
\ , ---- -----,- • ".
.
~ ,,-- --- , '.' f--- .-
.
.' o
".
,
. .
'~, ,
'.
,0
I . - . v .
. , , , . .
20
.
,
I
, .. ,
I
, .
, " . . WELL 812, YUF CO,," in, !I£ 4NE 1/4 SEC. I '[ S 5 .• R.17W. , .
10000
" DEPTH '08 FE T, IRRI TION ELL , I-~- -- 1-."- -, - --- -- ~
40 - ". -- C---' -- c-- , . ----1---- --- --,- -- ,
C-,---1---- -- -,,:",-
.000
'LEGEN[ . o . .
, OEP H TO ~TER •
, -- -TOTA sOUC I '
1925 1926 1927 1928 1929 '930 1931 1932 1933 19" 1935 -'93S" 1937 '9" '939 '940 1941 1942 194' 't044 '94' 1948
, . .
FIG. 2 - GRAPHS C SHOWING FWCTUATlONS 'oF WATER LEVEL IN TYPICAL OBSERVATION WElLS. AND THE
CHANGES, IN DISSOLVED SOUDS, WELLTON-MOHAWK AREA. _ YUMA COUNTY. ARIZONA .
UUl
•