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<br />lllCSHop farm. The new pipes will fol.
<br />low lhe !)aIllC (nurse as the old Jil.:h aull
<br />ci.Lrry the same amount of water. The
<br />only diUcrclKc IS the water won'llOuch
<br />Ihcgrollllll,Dr!.he sail.
<br />Tharp and Eller, the secoml and
<br />thud gcncr<Jlion." lO nm the family farm.
<br />arc among Ihe first f<.Lrlllers III weston
<br />Culur,hlu's (iunnisun Kiver Basiu to join
<br />lhe Colorado ki\lcr Basin Sailnity
<br />Control Program.
<br />Run hy Lhe Bureau of Rcdalll:llioll
<br />:lntl the ilcparUncnl of Agriculture. lhe
<br />Color;ulo River Basin Salinity Culllrol
<br />I'lOgram is lhe nation's lirst serious
<br />allcmpl al cOlllfOlIing a non-point poilu-
<br />unt- a huge. muILi-pha.-.c, seven-slale,
<br />Ji)-year, billion.dollar eHort. But no olle
<br />knows if ii's going to work.
<br />
<br />USDA's pari of the salinity coolrol
<br />program, eSlimaLes there arc about 1.7
<br />million acres of irrigmed fannland in thc
<br />Colorado basin; IOgclher thcy conlribme
<br />37 pcrcelltof the rivcr'ssallloao.l.
<br />Salts addcd by agriculture in lhe
<br />upper basin lJO.:Come highly cunccntmtcd
<br />whClll.hey hit the lower hasin, wherc the
<br />river's flows have bee II significantly
<br />depicted by evaporation from reservoirs
<br />and diversiuns lO farms and cities. lbe
<br />Colorado is the only major river in the
<br />country that has more water al iLS llead
<br />tllall where it runs to the ~.
<br />Bureau 01 Kcdamation stUilies esu-
<br />mate that waler loss due lU reservoir
<br />evapormion COlllributes 12 pcn:ent 01 the
<br />salt problem, while the annuaJ divasion
<br />of ovcr 5 million acre-feet of watcr hom
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<br />salt levels sl<med to rise early on, it wa.~
<br />1I0t considered serious until the 1960s.
<br />Then the last user on Ihe river, Mexico,
<br />got dose!1 with a surge of water with
<br />enough salt ill it 10 SIUllt crops in Ihe
<br />Mexicali Valley, render the water
<br />undrink:lble, allll, the Mexicans com.
<br />Illainc..l, violme the 1944 lluitel.! Slales-
<br />Mcxiw treaty guamntccing waler deliv.
<br />cries lU Mexico. Mexico claimcd that
<br />receiving its full share of water was
<br />lIll..';llliugkss if thaI water werc su sally it
<br />wuuld kill or stllnt crops.
<br />That salt did not come frolll the
<br />upper Culor<.ldo uminstcIII. It callie frum
<br />just across the bOlller. where the
<br />Wclltoll-Muhawk irrigation district on
<br />the Gil<.l Hiver ill ArilOna drops il~ retum
<br />nuws back into the river. Desert farming
<br />re1luircs irrigation, but to keep an irrigat-
<br />ed ClOp'S root zoncs free of conslantly
<br />rising, sally water lables, llesert farming
<br />also requires drainage.
<br />The Bureau or Red<.lm.llion com-
<br />pleted Wellton-Mohawk's drainage pro-
<br />ject in 1961. and when the agency tumcd
<br />011 the pumps to lower the waler tablc it
<br />drew up water conlaining about 6,(X)()
<br />mgt1 of salt, and dumped Ihat in In the
<br />Colorado just Ujlstrealll of the Mcxican
<br />border. Det:ausc hardly allY water is Idt
<br />in the river at thai point. Mexico got
<br />nows wilh salt concenlrations as high as
<br />2.700mg/1.
<br />That precipitalcd a billcr argumcnt
<br />lhat cndcl.! ill 1973 with the signing of an
<br />inlCrnatiunal accord. The Unitel.! Slates
<br />agreed In ddivcr waler to Mexko with
<br />an annual averagc salinity of 110 more
<br />Ih:Ul 115 parts pn million, plus or minus
<br />30 ppm, owr lhc annllal average sallnilY
<br />atlmp.:rial Dam, the IICXI dam upstream
<br />on the American sille (I/CN, Il/JOIH6).
<br />A canal was dug to divert the Wcllton-
<br />Mohawk drainage WOller dircctly 10 the
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<br />the 1922 compact.
<br />The stales organi:;:ed Ihemselves imo
<br />the Color:ulo River Basin Salinity
<br />Cllmwl Forum aud prcssured the EI'A to'
<br />accept its hasin-wille uppm..1ch to salini-
<br />ty. The EPA eventually agreed, bUI
<br />rC1lllirc..1 the {,)turn 10 den'lop slafldard.~
<br />III h'\'p s,lll in Ihe JIlwcr river to 11)72
<br />levels. The forum and the EI'A finally
<br />agrecd on those lHllIIbas in 1976, ;11111
<br />selecled three mcasuring slat ions in lhe
<br />lower basin. Those standards and sta-
<br />tions arc; 723 IlIg/l helow II00ver J);IlIl.~
<br />747 mg/l heluw Parker Dalll, OIl1d H79
<br />lllg/l at Impl..'rial Dmn. ~:
<br />Based 011 those two lreaties - thG:,..J
<br />acwrd wilh Mexko and the impclldin!J'.
<br />agrecment wilh the seven basin sL;ues-
<br />Ihe U.S. Congress passed Ihe Colorallo
<br />River Basin Salinity Control ACI ill
<br />1974. It has two parLS. Tille I is intemlcll
<br />10 clean up Wclllon.Mohawk's drainage
<br />problem lO meet the uealy obligation to
<br />Mexico. It gave the Bureau $156 mil-
<br />lion, most of which wa~ allocaled to con-
<br />struct a desalinization plant in Yuma,
<br />Ariz., 10 IrC<11 WclltulJ.Mohawk drainage
<br />water. But some of the l\loncy also went
<br />10 huild a series of projects 10 increa-;c
<br />Wdhon.~lohawl. 's irrigalion d'fkicncy.
<br />Tillc II established the Colorado
<br />Hiver Basi II SalinilY COlllrol Program
<br />for the bOlsin above Imperial Dam and
<br />lai,1 out the strategy thai the program has
<br />fullowed 10 dalC: individual salinilY con-
<br />trol projccts wOld,1 he developed and
<br />brought 011 line at the same nlle as water
<br />devclopmclll projl',clS were finished, thus
<br />keeping salt levels at the three lower
<br />hasin mcasuring sl,uiollS below lhe slan-
<br />dard agreed to hy the slales and EPA,
<br />The strategy sprC<ld the costs of the
<br />program out over nearly four decades.
<br />Originally four projccts were authorized
<br />[or coostruction and 12 for planning: the
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